Platinum Notes - Anatomy ( 2014-15 )

7/25/2019 Platinum Notes - Anatomy ( 2014-15 )

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1 ANATOMY

“Te ext contains Highly Concentrated opics which are likely to be asked in the Examinations. A student is suggested to read thebelow text with high degree o concentration and depth. Multiple revisions are advised.”

GENERAL ANATOMY

Father o Modern Anatomy: Vesalius TN 2007

IMPORTANT VESSELS AND SOURCE OF BLEEDING (HIGH YIELD FOR 2014 )

It is very essential to remember the source o bleeding rom some important vessels:

Duodenal ulcer: Gastroduodenal artery . AIIMS 2011

EDH (Extradural hematoma): Middle meningeal artery UPSC 2000

Gastric u lcer: Left gastric artery Hemoptysis: Bronchial artery Menstruation: Spiral arteries

SDH (Sub dural hematoma) Bridging veins

Tonsill ectomy: Paratonsill ar vein AI 1990

Posterior wall perforation leads to bleeding due to involvement of gastroduodenal artery that lies posterior to the 1st part of duodenum.

rauma to skull near the Pterion exactly opposite to which lies the middle meningeal artery inside the skull (gure below). Acute Epiduralhematoma: Usually follows arterial hemorrhage between the skull and the dura. At the time of impact, a dural artery is torn, and the

inbending of the skull initiates the stripping of the dura from the bone. Occasionally, an epidural hematoma follows a torn venous sinus.

Most frequently, acute epidural hematomas occur in the temporal or temporoparietal region as a consequence of hemorrhage from one

of the branches of the middle meningeal artery.



2 Platinum Notes 2014-15

IMPORTANT MEMBRANES IN BODY

Huxles Membrane: Inner layer of cells of root sheath of hair AIIMS 1995

Henle's Membrane: Outer layer of cells of root sheath of hair AIIMS 1995

Bowman's Membrane: “Anterior” limiting membrane of Cornea

Descemet’s Membrane: “Posterior” limiting membrane of Cornea

Bruchs Membrane: Pigment membrane in Retina

Elsching's Membrane: Astroglial membrane covering Optic Disc

Heuser's Membrane: Exocelomic Membrane

Sharpnell's Membrane: Pars Flaccida of the tympanic membrane MP 2007

IMPORTANT DUCTS

Parotid duct Stenson's duct

Opens opposite upper 2nd molar in vestibule of mouth.

MAH 2012

Submandibular duct Wharton's duct.

Pancreatic duc t Wirsung's duct

Accessory pancreatic duct Santoniris duct

Gartners duct Remanant of Mesonephric duct (WOLLFIAN) DNB 2008

Thoracic duct Pecquet's duct PGI 1999

Paramesonephric Duct Mullerian Duct

IMPORTANT ANATOMICAL LINES (HIGH YIELD FOR 2014)

Hiltons line: At level o interval between subcutaneous part o external sphincter and lower border o internal anal sphincter. Felt as a

groove on digital examination. Pectinate line: Circular line o attachment o anal valves.

Holdens line: Lateral to pubic tubercle about 8 cms . prevents extravasation o urine into lower limb.

Reid's base line: Horizontal line between inraorbital margin and centre o external acoustic meatus.

IMPORTANT TYPES OF CELLS: (HIGH YIELD FOR 2014)

Continuously Dividing Cells or Labile Cells

Epithelial cells

Cells o bone marrow & hemopoietic tissue.

Quiescent Cells or Stable Cells

Can undergo division in response to stimuli.

Are in Go phase but can go into Gl.

Cells include :

Parenchymal cells o liver , kidney, pancreas,

Mesenchymal cells,

Ffibroblasts

Smooth muscles & vascular endothelium.



Platinum Notes 2014-15 3

Non-dividing Cells or Permanent Cells

Nerve cells

Skeletal & cardiac muscle cells.

IMPORTANT CANALS IN HISTOLOGY

Herrings Canal: Fine terminal ductules lined by cuboidal epithelium lining. Intralobular bile canaliculi with bile ducts in portal canals

Petit Canal: Space between zonules o Zinn and Viterous humor

Rosenthal's Canal: Spiral canal o Cochlea

Schelmm's Canal: Canal at sclerocorneal junction UPSC 2003

Volkman's Canal: Osseous canal carrying blood supply rom periosteum

Haversian Canal: Neurovascular channel around which the lamella arranged in concentric cylinders in a bone.

Other Important Canals

Haversian canals: Central vascular channels in Haversian systems

Guyon’s canal: Canal for the ulnar nerve and vessels; dened medially by the pisiform, and posteriorly by the exor

retinaculum

Hunter’s canal: Canalis adductorius. The adductor canal

Alcock ’s canal: Canalis pudendalis

Dorello’s canal: An opening sometimes found in the temporal bone through which the abducens nerve and inferior

petrosal sinus together enter the cavernous sinus

Canal of Nuck: A diverticulum of the peritoneal membrane extending into the inguinal canal, accompanying the round

ligament in the female, or the testis in its descent into the scrotum in the male; usually completely obliterated in the female.

Stilling’s canal : A minute canal running through the vitreous from the discus nervi optici to the lens

Palatovaginal canal: Transmits pharyngeal branch from pterygopalatine ganglion and pharyngeal branch from maxillary

artery

Vomerovaginal canal : transmits pharyngeal vessels and nerves

Important Valves of Body

Hasners valve • Nasolacrimal duct JKBOPEE 2012

Thebesian valve. • Valve of the coronary sinus

Heisters valve • Valves of the duct of gallbladder cystic duct

Valves of Kerckri ng • Valves at the mucosal surface of the small intestine contains

numerous circular mucosal folds

IMPORTANT DIAPHRAGMS OF BODY (HIGH YIELD FOR 2014)

Diaphragm o oral cavity: Mylohyoid JKBOPEE 2012

Diaphragm o superior thoracic aperture: Sibsons Fascia

Pelvic diaphragm: Levator ani and coccygeus

Urogenital diaphragm: Deep transverse perinei and sphincter urethrae, perineal mermbrane. AI 2010

Diaphragm sella: Fold o duramater overlying pituitary ossa

Iris diaphragm: In eye




Important Fascias

Toldt's fascia • Anterior renal fascia

Zuckerkandl fascia • Posterior renal facia

Bucks fascia • Deep fascia of penis AMU 1986

Denonvill ers fascia:2 • Fascia separating rectum from prostate

KAR 2008

DNB 2011

KCET 2012

Waldeyers fascia fascia separating Rectum from Coccyx

Campers f ascia Supercial fatty layer of supercial fascia

Scarpas fascia Deep membranous layer of supercial fascia

Fascia Colli Investing layer of deep cervical fascia of neck

Fascia transversalis Forms anterior wall of femoral sheath

Fascia iliaca Forms posterior wall of femoral sheath

Pelvic f ascia Forms hypogastric sheath AI 2010

IMPORTANT TRIANGLES (HIGH YIELD FOR 2014)

Triangle of Koch (In Heart)

It is bounded by PGI 2005

Tricuspid valve,

Margin of coronary sinus opening

Tendon of Todaro. AIIMS 2003

It is a part of brous skeleton of the heart.

The tendon of Todaro is a continuation of the Eustachian Valve of the Inferior vena cava and the Thebesian valve of the

coronary sinus. Along with the opening of the coronary sinus and the septal cusp of the tricuspid valve it makes up the

triangle of Koch. The center of the triangle of Koch is the location of the atrioventricular node. It makes up the triangle of

Koch. The centre of the triangle of Koch is the location of the atrioventricular node.




Triangle of Auscultation (On Back)

Only part of back not covered by muscles. JK BOPEE

Respiratory sounds are best heard here.

Boundaries:

Medial border o f scapula laterally DNB 2008

Lateral border of trapezius medially DNB 2008

Upper border of latissmus dorsi in feriorly.

~ It is a small triangular space on the back where the relatively thin musculature allows for respiratory sounds to beheard more clearly with a stethoscope.

The oor is formed by:

7th rib

6th & 7th intercostal spaces

Rhomboideus major

On the lef side, the cardiac orifice o the stomach lies deep to the triangle, and in days beore X-rays were discovered the sounds oswallowed liquids were auscultated over this triangle.

Triangle of Petit: (Lower Abdomen)

Superiorly: 12 th rib

Ineriorly: Iliac crest

Laterally: Posterior border o external oblique muscle

Lessers Triangle: (Neck)

Hypoglossal nerve above

wo bellies o digastric on either sides




Hasselbach's Triangle (Inguinal Region)

It is Bounded by PGI 1985

Lateral margin of Rectus Abdominis Medially, Inferior epigastric artery laterally and

inguinal ligament inferiorly

Triangle of Doom (Laproscopic)

Gonadal vessels laterally AIIMS 2008

Vas deerens medially

MC Ewans Suprameatal Triangle (ENT)

Triangular depression posterior to external acousti c meatus. JK BOPEE 2011

It is bounded by post erosuperior margin of external acoustic meatus,

Supramastoid crest and

A vert ical l ine tangent to poster io r border of ex ternal acoustic meatus

Triangle of Pain (Laproscopic)

Lateral to triangle o doom:

Gonadal vessels medially

Iliopubic tract laterally

ineriorly by inerior edge o skin incision.

Circle of Death

Called corona mortis. It is a vascular ring ormed by an arterial network:

common iliac artery,

internal iliac artery,

external iliac artery,

obturator artery,

accessory obturator artery and

inerior epigastric artery.

Trautman Triangle (ENT)

Anterior: bony labrynth

Posteriorly: sigmoid sinus

Above: superior petrosal sinus




Important Angles

Neck shaft angle of femur i n adults: 1250. More in females

Angle of femoral torsion: 15°

Carrying angle: Angle made by long axis of arm with long axis of forearm. 170°

Angle of humeral torsion: 164°

Renal angle: junction of 12 th rib with erector spinae muscle

Lovibonds angle: angle between nail plate and proximal nail fold.

Sternal angle: angle of Louis

Citteles angle: Sino dural angle

Alpha angle : (in eye) between visual axis and optical axis

Kappa angle: (in eye) between pupillary axes

Cobbs angle: used in scoliosis

Cubitus valgus is increase in carrying angle. Feature o urners syndrome.

Coxa vera: reduction in neck shaf angle o emur

Coxa valga: increase in neck shaf angle o emur

Lengths of Important Structures

Female urethra: 4 cms

Male urethra: 18-20 cms Kerala 2008

Spinal cord: 18 inches or 45 cms

Femur: 18 inches or 45 cms

Vas defrens, 18 inches or 45 cmsThoraxic duct: 18 inches or 45 cms

Ureter: 10 inches

Esophagus: 10 inches UPSC 2005

Trachea: 4-6 inches

Foramina asked in Exams

Foramen o Morgagni reers to an opening in: Te Diaphragm (DNB 2006)

Foramen o Winslow is: Between greater and lesser sac (DNB 2006)

Foramen o Magendie, Lushka are related to ourth ventricle

Foramen o Monro is Interventricular oramen (Brain)

Foramen o Vesalius (Emisary Sphenoidal Foramen)

Important Arteries and Their Branches (High Yield fo r 2014)

Axil lary artery

Is continuation o subclavian artery.

Pectoralis minor divides it into three Branches




Ist part:

Superior thoracic artery. AIIMS 1998

2nd part:

Thoracoacromial artery. Lateral thoracic artery.

3rd part:

Subscapular artery.

Anterior circumex humeral artery.

Posterior circumex humeral artery

BRANCHES OF INTERNAL CAROTID ARTERY

No branches in neck

Caroticotypanic

Pterygoid

Cavernous branch to trigeminal ganglion

Superior and inferior hypophyseal

Opthalmic

Anterior cerebral

Middle cerebral

Posterior communicating

Anterior choridal

BRANCHES OF EXTERNAL CAROTID ARTERY

Superior thyroid

Lingual

Facial

Occipital

Posterior auricular

Ascending pharyngeal

Maxillary

Superficial temporal

BRANCHES OF SUBCLAVIAN ARTERY

Vertebral artery,

Internal thoraxic artery,

Tyrocervical trunk (Inerior thyroid, suprascapular, superficial cervical)

Costocervical trunk (Superior intercostal, Deep cervical)

BRANCHES OF VERTEBRAL ARTERY

Spinal

Muscular

Meningeal




Anterior spinal

Posterior spinal

Posterior inerior cerebellar

Medullary

BRANCHES OF BASILAR ARTERY

Formed by union o two vertebral arteries:

Posterior cerebral arteries

Superior cerebellar

Pontine

Labrynthine

Anterior inerior cerebellar

BRANCHES OF INTERNAL ILIAC ARTERY

is smaller terminal branch of common iliac artery.

It is about one and half inches long (3-3.5cm).

It begins in front of sacroiliac joint.

It divides into ant. and post. Divisions at upper margin of greater sciatic notch.

Branches from An ter io r Division : (Six in males and seven in females.)

Superior vesical artery.

Inferior vesical. COMED 2003

Obturator

Middle rectal

Inf.Gluteal.

Internal pudendalIn females, inferior vesical is replaced by vaginal artery

Uterine artery is the 7th branch in females. UPSC 2001

Branches from Posterior Division:

Superior gluteal.

IIio lumbar.

Lateral sacral.

QUESTIONS ASKED IN VARIOUS EXAMINATIONS

Inferior thyroid artery is a branch of: • throcervical trunk • PGI 2003

Ascending pharyngeal ar tery i s a branch of • external carotid artery • TN 2004Internal pudendal artery in f emales is a branch of • internal iliac artery • DELHI 1992

Left gastroepiploic artery is a branch of • spleenic artery • AI 1989

Spleenic artery is a branch of • celiac trunk • PGI 1988

Uterine artery is a branch of • internal iliac artery • PGI , UPSC 1989

Cystic artery is a branch of • right hepatic artery • PGI 2001

Cilio retinal artery is a branch of • choridal artery • TN 2002

Middle meningeal artery is a branch of • maxillary artery • UPSC 1986

Anter io r spinal artery is a branch o f • veretebral artery • PGI 1993

Opthalmic artery is a branch of • internal carotid artery • PGI 1993




Blood Supply of Important Organs (High Yield for 2014)

Testis • Testicular artery: Branch of Abdominal Aorta

Epididymis • Testicular artery: Branch of Abdominal Aorta

Esophagus • Cervical part: inferior thyroid artery

• Thoracic part: oesophageal branches of aorta

• Abdominal par t: oesophageal branches of left gastric artery.

Stomach • Left gastric artery: branch of coeliac trunk

• Left gastroepiploic artery: branch of splenic

• Right gastric artery: branch of common hepatic

• Right gastroepiploic artery: branch of gastroduodenal

• Short gastric arteries: branches of splenic

Liver • The blood supply of the liver: Liver is unique in the fact that it receives most

of its blood from a vein (Portal Vein). Liver receives 20% of its blood fromhepatic artery and 80% from portal vein.

Gall Bladder • The cystic artery (usually a branch of right hepatic artery) supplies blood to

gall bladder, cystic duct, hepatic ducts and upper part of the bile duct.The cystic

artery is an End artery.

Duodenum • The part above the level of common bile duct opening is supplied by

superior pancreaticoduodenal artery and below it by the inferior

pancreaticoduodenal artery.

Colon • The right 2/3 of transverse colon develops from midgut, so it is supplied by

superior mesenteric artery.

• The left 1/3 is formed from hindgut, so it is supplied by inferior

mesentericartery

• The arterial supply of the large intestine is derived from both the superior andinferior mesenteric arteries.

• Those parts derived from the midgut (caecum, appendix, ascending colon and

right two-thirds of the transverse colon) are supplied from colic branches of the

superior mesenteric artery;

• While hindgut derivatives (left part of the transverse, descending and sigmoid

colon, rectum and upper anal canal) are supplied predominantly from the

inferior mesenteric artery, with small contributions from branches of the

internal iliac artery.

• The larger unnamed branches of these vessels ramify between the muscular

layers of the colon which they supply. They subdivide into smaller submucosal

rami and enter the mucosa. The terminal branches divide into vasa brevia

and vasa longa which either enter the colonic wall directly or run through the

subserosa for a short distance before crossing the circular smooth muscle togive off branches to the appendices epiploicae

Appendix • The appendix is supplied only by appendicular artery, a branch of ileo-colic

artery. It runs rst in the free edge of appendicular mesentery and then distally

along the wall of appendix.




Pancreas Pancreatic branches of splenic artery

Superior pancreaticoduodenal artery, a branch of coeliac trunk.

Inferior pancreaticoduodenal artery, a branch of superior mesenteric artery.

Adrenal/Suprarenal Superior suprarenal artery: branch of inf erior phernic

Middle suprarenal artery: branch of abdominal aorta

Inferior suprarenal artery: branch of renal artery.

Kidney Renal Artery: Branch of Abdominal Aorta

Ureter For upper part: renal artery, branches of gonadal and colic arteries.

For middle part: branches from aorta, gonadal and iliac arteries.

For lower part: from vesical, middle rectal or uterine arteries

Prostate in males The prostate is supplied by branches from the inferiorvesical, middle rectal internal pudend

arteries.

Ovaries in females Ovarian and uterine arteries.

Uterus in females Uterine and ovarian arteries. The uterine arteries are tortuous and permit expansionof uterus d

pregnancy.

Fallopian Tubes Uterine artery supplies the medial 2/3 and the ovarian artery supplies the lateral 1/3.

Vagina in females Vaginal branch of internal iliac artery

Cervicovaginal branch of the uterine artery

Middle rectal artery

Internal pudendal artery

Rectum Superior, middle and inferior rectal arteries and also by the median sacral artery.

Heart The right coronary artery arises from the anterior aortic sinus. It is smaller than left

The left coronary artery arises from the left posterior aortic sinus.

Trachea Inferior thyroid arteries

Pleura Parietal pleura: intercostals arteries

Internal thoracic arteries and

Musculophrenic arteries.

Visceral pleura: bronchial arteries

Lungs Bronchial artery

Pulmonary veins

Tonsil Tonsillar branch of f acial

Ascending palatine b ranch of lingual

Dorsal lingual branch of external carotid

Ascending pharyngeal b ranch of external carotid and

Greater palatine branch of maxillary

Palate Greater palatine branch of maxillary

Ascending palatine b ranch of maxillary and

Palatine branch of ascending pharyngeal




Thyroid Gland Superior thyroid artery: supplies upper 1/3 of lobes and upper ½ of isthmus.

Inferior thyroid artery: supplies lower 2/3 of lobes and lower ½ of isthmus.

Sometimes, lowest thyroid artery.

Accessory thyroid ar ter ies : from vessels to oesophagus and trachea

Littles area of Nose/

Keissselbachs Plexus

It is the anteroinferior part of nasal septum containing anastomosis between:

Superior labial branch of facial artery and sphenopalatine artery. Large capillary network.

The clinical importance of little’s area

It is the commonest site of bleeding from the nose

Brain Internal carotid arteries

Vertebral arteries: at lower border of pons join to form basilar artery

Circle Of Willis

Anter io rly: anterior communicating artery

Posteriorly: basilar artery as it divides in to two posterior cerebral arteries

On each side: anterior cerebral, internal carotid, posterior communicating and posterior cerebral

arteries.

Spinal Cord Anterior spinal artery; one

Posterior spinal artery: two

Ar ter ies of Adamkiewicz: These are the anastomotic arteries between anterior and posterior spinal arteries

at the level of T1 and T11.

EMBRYOLOGY

Important Events /Stages In Embryogenesis

Fertilization (Fusion o Male and Female Pronucleus)→ Implantation →wo Celled Embryo stage Tree celled embryo stage……………→Sixteen Celled embryo stage (Morula)→ Blastocyst (Fluid Accumulation) →Formation o Embryonic pole andAbembryonic pole→Formation o first germ layer(Endoderm)→Formation o Second germ layer (Ectoderm)(Bilaminar GermDisc)→ Formation o third Germ layer(Intraembryonic Mesoderm) “Gastrulation” (rilaminar Germ Disc ) → Developmento Yolk sac and Amniotic Cavity →Development o Primitive Streak And Prochordal Plate .

Sex Determination

All ova contain 22+X chromosomes

Te spermatozoa are o two types, hal o them have 22+x chromosomes and hal o them have 22+Y chromosomes.




I the sperm is X- bearing the zygote has 44+X+X chromosomes and the offspring is a emale.

I the sperm is Y –bearing the zygote has 44+X+Y chromosomes and the offspring is a male.

Capacitation

Are the physiochemical changes in the acrosomal cap o sperm .Due to this it gets the property o penetrating zona pellucida o the ovum.

Acrosomal Reaction

Is the release o acrosin. It is lysosomal and leads to dispersal o cells o corona radiate, digests zona pellucida and causesloss o acrosomal cap.

Fertilization

Is the process o usion o male and emale pronuclei resulting in the ormation o a zygote.

It takes place in the ampulla o the allopian tube.

Sperm binds to zona pellucida o the secondary oocyte and triggers acrosomal reaction.

Penetration elicits cortical reaction rendering secondary oocyte impermeable to other sperms.

Male and emale pronuclei meet but do not use and all mitochondrial DNA is o maternal origin.

Female Gametogenesis

• Oogonia are derived from yolk sac MAHE 1998

• Germ cells are derived from yolk sac ICS 2005

• Polar bodies are formed during oogenesis AI 2006

• Polar bodies are extruded 24 hrs prior to ovulation. AI 2008

Male Gametogenesis

Spermatogenesis occurs at temperature lower than body temperature. AI 2008

Y chromosome is ACROCENTRIC. AIIMS 2007

In absence of Y chromosome ovaries develop. AIIMS 2007

Sperms are stored in epididymis. AIIMS 1993

Length o mature human sperm is 50-60 microns. DNB 1992

Chromosomal Conguration of Important Cells in Gonads

Number of chromosomes in cells during Gametogenesis

Primordial germ cell, oogonia, spermatogonia • 46, 2N

Primary oocyte, Primary Spermatocyte • 46, 4N

Secondary oocyte, Secondary Spermatocyte • 23, 2N

Oocyte, Spermatid , Sperm • 23, 1N

IMPORTANT EVENTS AND THEIR TIME SEQUENCE: (DAYS)

Implantation occurs at : • 6 days

Uteroplacental circulation establishes at: • 11-12 days

Primitive streak appears on: • 13- 15 th day

Formed from:ectoderm RJ 2009

Angiogenesis: • 15th day




Closure of anterior neuropore • 24 days ORISSA 2004

Embryo develops by: • 8 week

Fetus is • > 8 weeks

Common Signaling Pathways Used During Development High Yield for 2014

Te differentiation o many different cell types is regulated through a relatively restricted set o molecular signaling pathways:

Morphogens. Tese are diffusible molecules that speciy which cell type will be generated at a specific anatomic location and direct themigration o cells and their processes to their final destination.

Tese include:

Retinoic acid,

ransorming growth actor bone morphogenetic proteins (BMPs), and

Te hedgehog and the Wnt protein amilies

Notch/Delta. Tis pathway ofen specifies which cell ate precursor cells will adopt.

ranscription actors. Tis set o evolutionarily conserved proteins activates or represses downstream genes that are essential or many

different cellular processes. Many transcription actors are members o the homeobox or helix-loop-helix (HLH) amilies. Teir activitycan be regulated by all o the other pathways described in this chapter.

Receptor tyrosine kinases (RKs). Many growth actors signal by binding to and activating membrane-bound RKs. Tese kinases areessential or the regulation o cellular prolieration, apoptosis, and migration as well as processes such as the growth o new blood vesselsand axonal processes in the nervous system.

SPECIFIC GENES / FACTORS INVOLVED: (HIGH YIELD FOR 2014)

OTX2

LIM 1

HESX1

Establishment of Cranial end of Embryo

BMP 4FGF Mesoderm Development

Brachury T Gene Middle and Caudal Regions of Embryo

Lefty2

PITX2

Left sidedness

Snail Right sidedness

BMP 4

TGF

Induction of Caudal Neural Plate

AER

Hoxd 9, 10, 11, 12, 13

Development of limbs

HOX B8 Position of limbs

Errors in Development are:

Malormation: A morphologic deect o an organ, part o an organ, or larger region o the body that results rom an intrinsically abnormaldevelopmental process. Intrinsic implies that the developmental potential o the primordium is abnormal rom the beginning, such as achromosomal abnormality o a gamete at ertilization. Most malormations are considered to be a deect o a morphogenetic or developmentalfield that responds as a coordinated unit to embryonic interaction and results in complex or multiple malormations.

Disruption: A morphologic deect o an organ, part o an organ, or a larger region o the body that results rom the extrinsic breakdown o, oran intererence with, an originally normal developmental process. Tus, morphologic alterations afer exposure to teratogens-agents such asdrugs and viruses-should be considered as disruptions. A disruption cannot be inherited, but inherited actors can predispose to and influencethe development o a disruption.

Deormation: An abnormal orm, shape, or position o a part o the body that results rom mechanical orces. Intrauterine compression that




results rom oligohydramnios-insufficient amount o amniotic fluid-produces an equinovarus oot or cluboot an example o a deormationproduced by extrinsic orces. Some central nervous system deects, such as meningomyelocele-a severe type o spina bifida-produce intrinsicunctional disturbances that also cause etal deormation.

Fetal landmarks (weeks)

Within 1 week Implantation

Within 2 week Bilaminar disc

Within 3 week Trilaminar disc (Gastrulation) AI 2002

Within 3 week Primitive streak begins to form,

Notochord forms NIMHANS 2001

Within 3-8 week Organogenesis,

Teratogen susceptibility maximum

Week 10 Genitalia with male and female characters

Primit ive Streak High Yield for 2014

Primitive streak: Sacrococcygeal teratoma

The rst sign of gastrulation is the appearance of the primitive streak

At the beginning of the third week, an opacity formed by a thickened linear band of

epiblast-the primitive streak-appears caudally in the median plane of the dorsal

aspect of the embryonic disc. Remnants of the primitive streak may persist and

give rise to a sacrococcygeal teratoma.

Development of Primit ive streak is by a Nodal Gene member of TGF Beta

(Transforming Growth factor)

Remanants of Notochord: Chordoma

Zona Pelluc ida

is an important Glycoprotein membrane that surrounds the ovum. It is important or Por proper implantation so as to prevent implantationat an Abnormal site.

Implantation of Ovum has to Occur in Uterus

o be specific in Uterine Endometrium. ype o Implantation in humans is Interstitial. (Blastocyst invades Uterine Endometrium) and comesto lie within endometrium .




Gastrulation

Is the stage o Formation o three germ layers or the Germinal Disc.(-: Tree Weeks Tree Layers)

Endoderm (First layer)

Ectoderm(Second Layer) Intraembryonic Mesoderm(Tird Layer)

Important Embryological Structures

Meckel's Diverticulum

This true diverticulum is a remnant of the vitelline duct and often contains ectopic gastic mucosa which can

cause bleeding and perforation. The bleeding is often painless.

AIIMS 2005

The Ductus venosus

is a shunt that bypasses the liver and carries blood from the umbilical vein directly to the IVC. Its remnant is

the ligamentum venosum.

TN 1988

The Ductus arteriosusis a shunt that bypasses the lungs to carry blood from the pulmonary artery to the aortic arch. Its remnant is

the ligamentum arteriosum.

TN 1993

The Urachus

becomes the median umbilical ligament. UP 2005

The 2 umbilical arteries becomes the medial umbilical ligaments.

Urachal stula from persistent allantois. MAH 2000

The Vitelline duc t

is a connection with the yolk stalk and bowel, but normally obliterates during week 7 of development.

UMBILICAL CORD

Connects fetus and placenta.

Is rich in whartons jelly.

Has 2 arteries and one vein. DNB 2007

AIIMS 89, TN 1989, PGI 1987

Rt umbilical vein di sappears, left is left.

In case of single artery onl y, congenital anomalies should be excluded.

Umbilical arteries carry deoxygenated blood.

Umbilical arteries don’t possess i nternal elastic l amina.

Vas vasorum are absent in cases of umbilical vessels.

STEM CELLS

Stem cells must be able to:

Divide to produce sufficient cells;

Differentiate into the cell types needed;

Survive afer transplant;

Mesh into the surrounding tissues;

Function properly or long enough to extend the recipient’s lie or to improve it significantly;

Avoid harming the recipient.




KARYOTYPING

In 1961 an international meeting was held at the University o Colorado Medical School in Denver, Colorado to standardize the ormator a normal human karyotype. Te ormat that evolved is known as the "Denver System."

Each chromosome has its own individuality as shown by its size, shape, and position o its kinetochore. Using the "Denver System," thechromosomes are put into similar groups designated by letters. Ten numbers are used to subdivide the chromosomes within the groupsdesignated by numbers based on the position o the kinetochore and the length o the chromatids. Te homologous chromosomes arepaired based on their banding.

X Chromosome belongs to group C

Y chromosome belongs to group G

Group A Ch 1,2,3

Group B Ch 4,5

Group C Ch 6,7,8,9,10,11,12,X

Group D Ch 13,14,15

Group E Ch 16,17,18

Group F Ch 19,20

Group G Ch 21,22,Y

TYPES OF CHROMOSOMES

• Metacentric • 1,3,16,19,20

• Submetacentric • 2,4,12,17,18

• X chromosome

• Acrocentr ic • 13,14,15,21,22

• Y chromosome

• Telocentric • Not present in humans

PLACENTATION: (HIGH YIELD FOR 2014)

Placenta

Shape- circular, flat disc (Discoid)

Diameter –20cms

Tickness- 2.5 cms

Weight – 500 gms

Surfaces-Maternal and foetal. The maternal surface is rough and raw and is divided into 15-20 cotyledons by septa. The foetal

surface is smooth and is covered with amnion and the umbilical vessels are seen shining .

The Decidua

Decidua reers to the gravid endometrium, the unctional layer o the endometrium . Te three regions o the decidua are namedaccording to their relation to the implantation site

Te decidua basalis is the part o the decidua deep to the conceptus that orms the maternal part o the placenta.

Te decidua capsularis is the superficial part o the decidua overlying the conceptus.

Te decidua parietalis is all the remaining parts o the decidua

Te etal part o the placenta is ormed by the villous chorion. Te chorionic villi that arise rom it project into the intervillous spacecontaining maternal blood.

Te maternal part o the placenta is ormed by the decidua basalis, the part o the decidua related to the etal component o the placenta.By the end o the ourth month, the decidua basalis is almost entirely replaced by the etal part o the placenta.






HE UMBILICAL CORD OR FUNIS : (HIGH YIELD FOR 2014)

Forms the connecting link between the etus and the placenta through which blood flows to and ro rom placenta.

Is covered by amnion.

Length is 30-100 cms Diameter is 1-2.5 cms

Is attached eccentrically on the placenta.

Contains

Whartons jelly

wo umbilical arteries and one umbilical vein

Lef umbilical vein: Right umblical vein disappears. Lef is lef

Ramnents o yolk sac

Ramnents o allanto-enteric diverticulum

Shows a marked spiral torsion which is possibly due to oetal movements.

Te tube o amnion with structures within constitute umbilical cord

TWINNING

Dizygotic twins (Fraternal):

Develop from 2 zygotes,

Have 2 placentae,

2 chorions,

2 amniotic sacs

Monozygotic twins(Identical):

1 placenta, 1 chorion,

2 amniotic sacs

Oligohydraminos: Low Level of Amniotic uid (< 400 ml) in Renal agenesis

Polyhydraminos: High Level of Amniotic uid (>2000 ml)

in Anencephaly,

Esophageal atresia,

Maternal Diabetes

Amniotic Band syndrome: when bands of amniotic membrane encircle and constrict parts of fetus causing limb amputations

and Craniofacial anomalies

Remamants of Important Fetal Structures

Fetal Structure Adult remanant

• R and L Umblical artery • Medial Umblical Ligament

• L Umblical vein • Ligamentum Teres

• Ductus venosus • Ligamentum Venosum

• Foramen ovale • Fossa Ovalis

• Ductus arteriosus • Ligamentum arteriosum




DERIVATIVES OF GERM LAYERS

Ectoderm Mesoderm Endoderm

Skin and most of

appendages

Musculoskeletal system Epithelial lining of GIT

Lens of eye Cardiovascular system Epithelial lining of Biliary tract. MP 2K

Epithelial linning of

Lower half of Anal canal

Kidney, ureter, Epithelial lining of Respiratory tract

Epithelial lining of

external auditory

meatus

Trigone of bladder(mesonephric duct absorption)

UP 2006

Epithelial lining of vagina

Epithelial lining of distal

part of male urethra

Posterior wall of female urethra Epithelial lining of auditory tube,

middle ear

Adenohypophys is Posterior wall of prostatic part of male urethra.

Reproductive tract except labia majora, minora and major

part of prostate

Mesothelium of pleural, pericardial and peritoneal cavities

Dentine of teeth

Cornea, sclera, choroid, ciliary body and iris of eye

Somites from paraxial mesoderm. TN 1995

H mole is decent in mesoderm. AIIMS 1999

Tympanic membrane is formed from all three layers UP 2003

Derivatives of Neural Crest High Yield for 2014

Neurons of spinal posterior nerve root ganglia. AIIMS 1986

Neurons of sensory ganglia. PGI 1986

Neurons of autonomic ganglia(sympathetic ganglia) AI 2002

Schwann cells KERALA 1987

Melanocytes PGI 2003

Piamater and arachnoid matter.

Mesenchyme of dental papillae MP 2K

Cartilage cells of branchial arches

Chromafn tissue

Defective Migration of Neural Crest Cells Results in

Albinism

Melanoma

Hirschsprungs disease KERALA 2001. UP 2000

Oropharyngeal teratoma

Neurocristopathies (Clef Lip, Clef palate, Digeorges syndrome, Waarden burgs syndrome, CHARGE syndrome




NEURAL MIGRATION DISORDERS

Lissencephaly AIIMS 2011

Schizencephaly

Porencephaly AIIMS 2011

Agyria

Macrogyria

polymicrogyria

Tumors of neural crest or igin

Neuroblastoma

Phaeochromocytoma

Carcinoid umor

Neurofibromatosis

Medullary carcinoma Tyroid

DEVELOPMENT

Pharyngeal Apparatus

Pharyngeal Arches are derived rom Mesoderm

Pharyngeal clefs are derived rom Ectoderm

Pharyngeal Pouches are derived rom Endoderm

Pharyngeal Arch 1 Derivatives: (High Yield for 2014)

Meckels Cartilage MAH 2010

Mandible,

Malleus,

Incus,




Spheno Mandibular Ligament UP 2007, DELHI 1991, DELHI 1993

Muscles: Muscles o Mastication (Medial Pterygoid and Lateral Pterygoid, Masseter, emporalis)

wo ensors (ensor ympani ensor Palati)

Mylohyoid, anterior belly o digastrics

Pharyngeal Arch 2 Derivatives (WordS)

Reicherts Cartilage:

Stapes,

DNB 2008

Styloid process,

Smaller cornu of Hyoid Bone,

Superior surface of Hyoid Bone,

Stylohyoid ligament, KAR 1999

Muscles of facial expression, Stapedius, Stylohyoid, Posterior Belly of Digastric MAH 2001

Platysma MAH 2001

Stapedial artery is a remanent of 2nd arch Mah 2010

Pharyngeal Arch 3 Derivatives

Greater cornu o Hyoid Bone AP 1998, JIPMER 1987

Stylopharyngeus muscle

Tink o Stylo pharyngeus when thinking about Glosso pharyngeal Nerve

Pharyngeal arch 4 and 6 Derivatives

Cartilages o larynx ,

Intrinsic muscles o Larynx and pharynx MAH 2012

Pharyngeal arch 5 does not contribute to development

Nerve Supply of Pharyngeal Arches is : (My Father Gaveme Some Rupees)

Mandibular Nerve Ist arch

Facial Nerve 2nd arch

Glossopharyngeal Nerve 3 rd arch AI 1994, UP 2003

Superior laryngeal Nerve 4 th arch

Reccurent laryngeal Nerve 6 th arch MAH 2011

Pharyngeal Pouch Adult Structure

• Pharyngeal Pouch 1 Epithelial linning o Auditory tube/ Middle ear

• Pharyngeal Pouch 2 Palatine tonsil PGI 1988

• Pharyngeal Pouch 3 Inerior parathyroid and Tymus DNB 2011

• Pharyngeal Pouch 4 TN 2006 Superior parathyroid and Ultimobranchial body

Para ollicular cells are derived rom ultimobranchial body

KERALA 1987




Pharyngeal Clef/Groove Adul t St ructure

1 UP 2005 External linning of External auditory meatus

2, 3, 4 Obliterated

Meatuses and their openings: (High Yield for 2011/2012)

Meatus Opening

Superior meatus Posterior ethmoidal sinus

Middle meatus Maxillary sinus

Middle ethmoidal sinus

Frontal sinus

Inferior meatus Nasolacrimal duct JKBOPEE 2012

Treacher-Collins Syndrome / Mandibulofacial Dysostosis

Abnormal ormation o pharyngeal arch

Faulty migration o neural crest cells.

Patients are mostly characterized by the ollowing abnormalities:

Hypoplasia o the acial bones. An underdeveloped mandibular and zygomatic bone leading to a small and malormed jaw.

Ear anomalies. consist small, rotated or even absent ears.with or without bilateral stenosis or atresia o the external auditory cannels

Eye problems, varying rom colobomata o the lower eyelids and aplasia o lid lashes to short, downslanting palpebral fissures andmissing eyelashes. Vision loss can occur and is associated with strabismus, reractive errors, and anisometropia.

Clef palate

Airway problems, who are ofen a result o mandibular hypoplasia.

Dental anomalies consist in tooth agenesis , enamel disormaties and malplacement o the maxillary first molars .

Less requent deects are:

Nasal deormity

High-arched palate

Coloboma o the upper lid

Ocular hypertelorism

Choanal atresia

Macrostomia

Preauricular hair displacement

Cleft Lip and Cleft Palate (High Yield for 2014)

Unilateral cleft lip. Also called Hare lip Failure of fusion of medial nasal process with maxillary process

Midline defect of upper lip Defect in development of lowermost part of frontonasal process

Midline defect of lower lip Defective fusion of mandibular processes

Microstomia Excessive fusion of maxillary and mandibular processes

Macrostomia Inadequate fusion of maxillary and mandibular processes

Oblique facial cleft Non fusion of maxillary and lateral nasal process




Tongue Development

• 1st pharyngeal arch forms ant2/3

• 3rd and 4th arch forms post 1/3

• Muscles of tongue develop from occipital myotomes AIIMS 2007

• Muscles o tongue are both smooth and skeletal muscles MP 2009

THYROID DEVELOPMENT

Te Tyroid develops in relation to tongue rom Foramen Cecum between two Lingual Swellings.

Embryology of Lungs

By the ourth week, a laryngotracheal diverticulum develops rom the floor o the primordial pharynx.

Te laryngotracheal diverticulum becomes separated rom the oregutby tracheoesophageal olds that use to orm a tracheoesophagealseptum. Tis septum results in the ormation o the esophagus and the laryngotracheal tube.

Te endoderm o the laryngotracheal tube gives rise to the epithelium o the lower respiratory organs and the tracheobronchialglands. Te splanchnic mesenchyme surrounding the laryngotracheal tube orms the connective tissue, cartilage, muscle, and blood andlymphatic vessels o these organs.




Te distal end o the laryngotracheal diverticulum gives rise to a respiratory bud that divides into two bronchial buds. Each bronchialbud soon enlarges to orm a main bronchus, and then the main bronchus subdivides to orm lobar, segmental, and subsegmental branches.

Each tertiary bronchial bud (segmental bronchial bud), with its surrounding mesenchyme, is the primordium o a bronchopulmonarysegment. Branching continues until approximately 17 orders o branches have ormed. Additional airways are ormed afer birth, until

approximately 24 orders o branches are present. Lung development is divided into our stages:

pseudoglandular (6-16 weeks),

canalicular (16-26 weeks),

terminal sac (26 weeks to birth), and

alveolar (32 weeks to approximately 8 years o age).

By 20 weeks, type II pneumocytes begin to secrete pulmonary suractant. Deficiency o suractant results in respiratory distress syndrome(RDS) or hyaline membrane disease (HMD).

A tracheoesophageal fistula (EF), which results rom aulty partitioning o the oregut into the esophagus and trachea, is usuallyassociated with esophageal Atresia

EMBRYOLOGY OF HEART HIGH YIELD FOR 2014

Embryonic structure Adult structure

Truncus arteriosus • Aorta

• Pulmonary Trunk

Bulbus cordis • Smooth part of R ventricle• Smooth part of L ventricle

Primitive ventricle • Rough part of R ventricle

• Rough part of L ventricle

Primitive atrium • Rough part of R atrium

• Rough part of L atrium

Sinus venosus MP 2004 • Smooth part of R atrium

• Coronary sinus (Lt horn of sinus venosus)

• Oblique vein of Left Atrium




EXTRA EDGE

Te primitive atrium gives rise to the trabeculated part o the right and lef atria.

Te primitive ventricle gives rise to the trabeculated part o the right and lef ventricles.

Te truncus arteriosus gives rise to the proximal portions o the ascending aorta and the pulmonary trunk. Te 3rd, 4th, and 6th aortic arches and the right and lef dorsal aortae contribute to the remainder o the aorta.

Te bulbus cordis gives rise to the right ventricle and the aortic outflow tract.

Te lef horn o the sinus venosus gives rise to the coronary sinus.

Te right common cardinal vein gives rise to the superior vena cava.

Te right horn o the sinus venosus gives rise to the smooth part o the right atrium

Embryology of Thoracic Vessels

Embryonic structure Adult Structure

• Aort ic arch 1

• Aort ic arch 2

• Aort ic arch 3 • Common Carotid artery

• Internal carotid artery (proximal part)

• Aort ic arch 4 • Rt. Subclavian artery (proximal part)

• Part of Aortic arch

• Persistence leads to double aortic arch DNB 2006

• Aort ic arch • Regresses

• Aort ic arch 6 • Pulmonary artery

• Ductus arteriosus

Ventral Mesogastrium Lesser Omentum, Hepatoduodenal, Hepatogastric, Falciform, Coronary and Triangular

Ligament of Liver

Dorsal Mesogastrium Greater Omentum, Mesentry of small intestine,Mesoappendix, Sigmoid Mesocolon, Transverse

Mesocolon

Remember

Embryology of Urinary Tract (High Yield for 2014)

Embryo Adult structure

Ureteric Bud Collecting duct AIIMS 1995Major/Minor Calyx

Renal pelvis

Ureter

Epithelium o ureter rom mesonephros. AIIMS 2007

Metanephric Mesoderm Renal Glomerulus

Bowmans capsule

PCT

DCT

Loop Of Henle

Collecting Tubule




Embryology of Genital tract: High Yield for 2014

SRY gene

SRY (or sex-determining region Y) is a gene located on the short (p) arm just outside the pseudoautosomal region. It is the master

switch that triggers the events that converts the embryo into a male. Without this gene, you get a emale instead. So emaleness is the "deault" program.

On very rare occasions aneuploid humans are born with such karyotypes as XXY, XXXY, and even XXXXY. Despite their extra Xchromosomes, all these cases are male.

(A test based on a molecular probe for SRY was used to ensure that potential competitors for the women's Olympic events in Atlantahad no SRY gene.)

SRY GENE

esteosterone

DH

Development o external male genitalia

Gonads Vary Testis

Paramesonephric duct or Mullerian duct RJ 2009

Non fusion of theses ducts leads to uterus diadelphus.

MAH 2012

• Uterine tubes

• Uterus

• Cervix

• Hydatid of morgagni

Appendix test is

Mesonephric “duct” or Wollan duct Appendix vesicu losa

Duct of Garnier JKBOPEE 2012

Epididymis, ductus

deferens

Seminal vesicles

Ejaculatory ducts

Appendix ep id idymis

Mesonephric “tubules” Epoophoroon JKBOPEE 2012 Efferent ductules

Paraphooron JKBOPEE 2012 Paradidymis

Phallus Clitoris Glans penis

Urethral folds Labia minora

Genital swellings Labia majora Scrotum

Te Urachus becomes the median umbilical ligament. JK BOPEE 2010

Te 2 umbilical arteries becomes the medial umbilical ligaments.

Obliterated umblical arteries orm lateral umblical ligament.

Urachal fistula rom persistent allantois.

Embryonic structure Female Male

• Genital ridge • Ovary (6 week) AIIMS 1991 • Testis

• Genital swelling • L. majora • Scrotum KERALA 1995

• Genital fol d • L. minora • Ventral aspect of penis

• Genital tubercle • Clitoris MAH 2002 • Glans penis




Diaphragm Development

Septum transversum

Pleuroperitoneal folds AIPGME 2011

Body wall

Dorsal Mesentry of esophagus

Development of Intraabdominal organs frequently asked :

Spleen

Is unique in respect to its development within the gut. While most of the gut viscera are endodermally derived(with the exception of the neural-crest derived suprarenal gland), the spleen is derived from mesenchymal tissue.

Specically, the spleen forms within, and from, the dorsal mesentery.

Pancreas

The pancreas develops between the layers of the mesentery from dorsal and ventral pancreatic buds of endodermal

cells, which arise from the caudal or dorsal part of the foregut. Most of the pancreas is derived from the dorsalpancreatic bud. The larger dorsal pancreatic bud appears rst and develops a slight distance cranial to the ventral

bud.

The Liver, Gallbladder and the B iliary duc t system

Arise as a ventral outgrowth (hepatic diverticulum) from the caudal foregut in the 4th week.

This hepatic diverticulum extends into septum transversum, a mass of splanchnic mesoderm between the developing

heart and the midgut.

The septum transversum forms the ventral mesentery in this region. This double-layered membrane gives rise to the

lesser omentum and the falciform ligament.

The superior layers of the coronary and left triangular ligaments meet and continue as a ventral mesentery attached

to the ventrosuperior aspect of the liver. AIIMS 2010

Gall bladder arises from pars cystica (from the hepatic bud).

Developmental Anomolies of Tongue

Ankyloglossia

Te lingual renulum normally connects the inerior surace o the tongue to the floor o the mouth. Sometimes the renulum isshort and extends to the tip o the tongue. Tis intereres with its ree protrusion and may make breast-eeding difficult. A shortrenulum usually stretches with time, making surgical correction o the anomaly unnecessary.

Macroglossia

An excessively large tongue is not common.

Microglossia

An abnormally small tongue is extremely rare and is usually associated with micrognathia (underdeveloped mandible and recessiono the chin) and limb deects (Hanhart's syndrome).

Bifid ongue

Fissured tongue

Developmental Anomolies of Larynx High Yield for 2014

Laryngeal Atresia

Tis anomaly results rom ailure o recanalization o the larynx, which causes obstruction o the upper etal airway. Distal to theregion o atresia (blockage) or stenosis (narrowing), the airways become dilated, the lungs are enlarged and echogenic




Laryngeal web

Results rom incomplete recanalization o the larynx during the 10th week. A membranous web orms at the level o the vocal olds,partially obstructing the airway.

Laryngoptosis:

Larynx is situated lower down in neck

Laryngeocele: excessive enlargement o saccule o larynx.

Developmental anomoli es of Trachea (High Yield for 2014)

Tracheoesophageal Fistula

A stula between the trachea and esophagus. Most affected infants are males. In more than 85% of cases, the

tracheoesophageal stula (TEF) is associated with esophageal atresia. A TEF results from incomplete division

of the cranial part of the foregut into respiratory and esophageal parts during the fourth week. Incomplete fusion of

the tracheoesophageal folds results in a defective tracheoesophageal septum and a TEF between the trachea andesophagus.

TEF is the most common anomaly of the lower respiratory tract. Four main varieties of TEF may develop. Theusual anomaly is for the superior part of the esophagus to end blindly (esophageal atresia) and for the

inferior part to join the trachea near its bifurcation. Polyhydramnios is often associated with esophageal

atresia. The excess amniotic uid develops because uid cannot pass to the stomach and intestines for absorption

and subsequent transfer through the placenta to the mother's blood

Developmental Anomolies of Cardiovascular System

Ectopia cordis: Non union o sternal plates exposing the heart to surace

Dextrocardia: I the heart tube bends to the lef instead o to the right ,the heart is displaced to the right and there is transposition-theheart and its vessels are reversed lef to right as in a mirror image. Dextrocardia is the most requent positional abnormality o the heart.In isolated dextrocardia, the abnormal position o the heart is not accompanied by displacement o other viscera.

Atrial Septal Deects: An atrial septal deect (ASD) is a common congenital heart anomaly and occurs more requently in emales than inmales. Te most common orm o ASD is patent oval oramen .A small isolated patent oval oramen is o no hemodynamic significance;however, i there are other deects (e.g., pulmonary stenosis or atresia), blood is shunted through the oval oramen into the lef atriumand produces cyanosis .

Common atrium is a rare cardiac deect in which the interatrial septum is absent. Tis situation is the result o ailure o the septumprimum and septum secundum to develop (combination o ostium secundum, ostium primum, and sinus venosus deects).

Ventricular Septal Deects: VSDs are the most common type o CHD. VSDs may occur in any part o the IV septum but membranousVSD is the most common type Frequently, small VSDs close spontaneously. Most people with a large VSD have massive lef-to-rightshunting o blood. Muscular VSD is a less common type o deect and may appear anywhere in the muscular part o the interventricularseptum. Sometimes there are multiple small deects, producing what is sometimes called the "Swiss cheese" VSD.

Cor biloculare: wo chambered heart

Cor riloculare: Tree chambered heart

L. cor triloculare biatriatum (wo atria, one ventricle): Absence o the IV septum-single ventricle or common ventricle-resulting romailure o the IV septum to orm, is extremely rare and results in a three-chambered heart (L. cor triloculare biatriatum).

Persistent runcus Arteriosus: Persistent A results rom ailure o the truncal ridges and aorticopulmonary septum to develop normallyand divide the A into the aorta and pulmonary trunk .In this deect, a single arterial trunk, the A, arises rom the heart and suppliesthe systemic, pulmonary, and coronary circulations.

Aorticopulmonary Septal Deect: Aorticopulmonary septal deect is a rare condition in which there is an opening (aortic window)between the aorta and pulmonary trunk near the aortic valve. Te aorticopulmonary deect results rom localized deect in theormation o the aorticopulmonary septum. Te presence o pulmonary and aortic valves and an intact IV septum distinguishes thisanomaly rom the persistent truncus arteriosus deect.

ransposition o the Great Arteries: GA is the most common cause o cyanotic heart disease in newborn inants .GA is ofenassociated with other cardiac anomalies (e.g., ASD and VSD). In typical cases, the aorta lies anterior and to the right o the pulmonary




trunk and arises rom the morphologic right ventricle, whereas the pulmonary trunk arises rom the morphologic lef ventricle. Teaorticopulmonary septum ails to pursue a spiral course during partitioning o the bulbus cordis and A. Tis deect is thought to resultrom ailure o the conus arteriosus to develop normally during incorporation o the bulbus cordis into the ventricles. Recent studiessuggest that deective migration o neural crest cells may also be involved.

etralogy o Fallot: Tis classic group o our cardiac deects: Pulmonary stenosis (obstruction o right ventricular outflow)

VSD

Dextroposition o aorta (overriding or straddling aorta)

Right ventricular hypertrophy

Coarctation o the Aorta: Aortic coarctation (constriction) occurs in approximately 10% o children and adults with CHDs. Coarctationis characterized by an aortic constriction o varying length. Most coarctations occur distal to the origin o the lef subclavian artery at the entrance o the DA (juxtaductal coarctation). Te classification into preductal and postductal coarctations is commonly used.Coarctation o the aorta occurs twice as ofen in males as in emales and is associated with a bicuspid aortic valve in 70% o cases.

Developmental Anomolies of Lymphatic System

Cystic hygroma: Large swellings usually appear in the inerolateral part o the neck and consist o large single or multilocular, fluid-filled cavities.Hygromas may be present at birth, but they ofen enlarge and become evident during inancy. Most hygromas appear to bederived rom abnormal transormation o the jugular lymph sacs. Hygromas are believed to arise rom parts o a jugular lymph sac thatare pinched off or rom lymphatic spaces that ail to establish connections with the main lymphatic channels. KCE 2011

Developmental Anomalies of GIT

Esophageal Atresia: Esophageal atresia is associated with tracheoesophageal fistula in more than 85% o cases. Atresia may occur asa separate anomaly, but this is less common. Esophageal atresia results rom deviation o the tracheoesophageal septum in a posteriordirection as a result, there is incomplete separation o the esophagus rom the laryngotracheal tube. A etus with esophageal atresia isunable to swallow amniotic fluid; consequently, this fluid cannot pass to the intestine or absorption and transer through the placentato the maternal blood or disposal. Tis results in polyhydramnios VAER association, an acronym or a nonhereditary concurrence oanomalies including vertebral or vascular deects, anal anomalies, E fistula, esophageal atresia, and radial limb or renal anomalies. Analternative acronym is VACERL (vertebral, anal, cardiac, tracheal, esophogeal, renal, and limb). AIPGME 2011

Esophageal Stenosis: Narrowing o the lumen o the esophagus can be anywhere along the esophagus, but it usually occurs in its distalthird, either as a web or as a long segment o esophagus with a threadlike lumen. Stenosis usually results rom incomplete recanalizationo the esophagus

Short Esophagus (Congenital Hiatal Hernia): Initially the esophagus is very short. Its ailure to elongate sufficiently as the neck andthorax develop results in displacement o part o the stomach superiorly through the esophageal hiatus into the thorax-congenital hiatalhernia. Most hiatal hernias occur long afer birth, usually in middle-aged people.




Dysphagia Lusoria: Abberant vessels compressing esophagus leading to dysphagia. Usually Abnormal right subclavian artery isimplicated. MAH 2009

Duodenal Atresia: Complete occlusion o the lumen o the duodenum. I recanalization o the lumen ails to occur a short segment othe duodenum is occluded Te blockage occurs nearly always at the junction o the bile and pancreatic ducts (hepatopancreatic ampulla)

but occasionally involves the horizontal (third) part o the duodenum. In inants with duodenal atresia, vomiting begins a ew hours afer birth. Te vomitus almost always contains bile; Duodenal atresia

may occur as an isolated anomaly, but other congenital anomalies are ofen associated with it, e.g., anular pancreas cardiovascularabnormalities, anorectal anomalies, and malrotation. Importantly, approximately one third o affected inants have Down syndromeand an additional 20% are premature. Duodenal atresia is associated with bilious emesis (vomiting o bile) because the blockageoccurs distal to the opening o the bile duct. Polyhydramnios also occurs because duodenal atresia prevents normal intestinalabsorption o swallowed amniotic fluid. Te diagnosis o duodenal atresia is suggested by the presence o a "double bubble" signon plain radiographs or ultrasound scans .Tis appearance is caused by a distended, gas-filled stomach and proximal duodenum.

AIIMS 2011

Riedels Lobe: A tongue like extension o right lobe o liver

Phrygian cap: Fundus o the gall bladder olded upon itsel giving rise to an appearance o cap worn by people o an ancient Asiancommunity o Phrygia.

Moynihans Hump: Normally the arterial supply o gall bladder is rom cystic artery which is a branch o Right hepatic artery . Sometimesan accessory cystic artery is also seen to arise rom either Gastroduodenal or right hepatic artery . Te Right hepatic artery takes atortuous course called “caterpillar turn” or “Moynihans hump.” Tis can be a source o prouse bleeding. JK BOPEE

Extrahepatic Biliary Atresia: Tis is the most serious anomaly o the extrahepatic biliary system and occurs in one in 10,000 to 15,000live births. Te most common orm o extrahepatic biliary atresia is obliteration o the bile ducts at or superior to the porta hepatis-a deeptransverse fissure on the visceral surace o the liver. Biliary atresia could result rom a ailure o the remodeling process at the hepatichilum or rom inections or immunologic reactions during late etal development. Jaundice occurs soon afer birth and stools are acholic(clay colored).

Accessory Pancreatic issue: Accessory pancreatic tissue is most ofen located in the wall o the stomach ,Wall o duodenum ,in an ilealdiverticulum (e.g., a Meckel diverticulum)

Anular Pancreas: May cause duodenal obstruction .Te ringlike or anular part o the pancreas consists o a thin, flat band o pancreatictissue surrounding the descending or second part o the duodenum. An anular pancreas may cause obstruction o the duodenum eithershortly afer birth or later. Inants present with symptoms o complete or partial bowel obstruction. Blockage o the duodenum develops

i inflammation (pancreatitis) develops in the anular pancreas. An anular pancreas may be associated with Down syndrome, intestinalatresia, imperorate anus, pancreatitis, and malrotation.

Congenital Omphalocele: Tis anomaly is a persistence o the herniation o abdominal contents into the proximal part o the umbilicalcord .Herniation o intestines and herniation o liver and intestines occurs.Te abdominal cavity is proportionately small when there is anomphalocele because the impetus or it to grow is absent. Surgical repair is required and is ofen delayed i the deect is very large. Inantswith these large omphaloceles ofen suffer rom pulmonary and thoracic hypoplasia and a delayed closure is a better clinical decision. Tecovering o the hernial sac is the epithelium o the umbilical cord, a derivative o the amnion.

High Yield for AIPGME/AIIMS/PGI 2013

Umbilical Hernia: When the intestines return to the abdominal cavity during the 10th week and then herniate through an imperectlyclosed umbilicus, an umbilical hernia orms. Tis common type o hernia is different rom an omphalocele. In an umbilical hernia, theprotruding mass (usually the greater omentum and part o the small intestine) is covered by subcutaneous tissue and skin. Te deectthrough which the hernia occurs is in the linea alba Te hernia protrudes during crying, straining, or coughing and can be easily reducedthrough the fibrous ring at the umbilicus. Surgery is not usually perormed unless the hernia persists to the age o 3 to 5 years.

Gastroschisis: Tis anomaly is a relatively uncommon congenital abdominal wall deect .Gastroschisis results rom a deect lateral tothe median plane o the anterior abdominal wall. Te linear deect permits extrusion o the abdominal viscera without involving theumbilical cord. Te viscera protrude into the amniotic cavity and are bathed by amniotic fluid. Te deect usually occurs on the rightside lateral to the umbilicus and is more common in males than emales.

Anomalies o the Midgut

Nonrotation occurs when the intestine does not rotate as it reenters the abdomen. As a result, the caudal limb o the midgut loop returnsto the abdomen first and the small intestines lie on the right side o the abdomen and the entire large intestine is on the lef.and the cecumlies just inerior to the pylorus o the stomach. Te cecum is fixed to the posterolateral abdominal wall by peritoneal bands that pass overthe duodenum. Tese bands and the volvulus (twisting) of the intestines cause duodenal obstruction. When midgut volvulus occurs, thesuperior mesenteric artery may be obstructed, resulting in infarction and gangrene of the intestine supplied by it. Infants with intestinal

malrotation are prone to volvulus and present with bilious emesis.




Reversed Rotation: In very unusual cases, the midgut loop rotates in a clockwise rather than a counterclockwise direction .As a result,the duodenum lies anterior to the superior mesenteric artery rather than posterior to it, and the transverse colon lies posterior instead oanterior to it. In these inants, the transverse colon may be obstructed by pressure rom the superior mesenteric artery

Congenital Megacolon or Hirschsprung Disease: Tis disease is a dominantly inherited multigenic disorder with incomplete

penetrance and variable expressivity. An absence o ganglion cells (aganglionosis) in a variable length o distal bowel. Inants withcongenital megacolon or Hirschsprung's disease lack autonomic ganglion cells in the myenteric plexus distal to the dilated segment ocolon. Te enlarged colon-megacolon has the normal number o ganglion cells. Te dilation results rom ailure o relaxation o theaganglionic segment, which prevents movement o the intestinal contents, resulting in dilation. AIPGME 2011

Imperorate Anus and Anorectal Anomalies: Imperorate anus occurs approximately once in every 5000 newborn inants and ismore common in males Most anorectal anomalies result rom abnormal development o the urorectal septum, resulting in incompleteseparation o the cloaca into urogenital and anorectal portions .Tere is normally a temporary communication between the rectum andanal canal dorsally rom the bladder and urethra ventrally but it closes when the urorectal septum uses with the cloacal membrane .

Anal Agenesis, with or without a Fistula: Te anal canal may end blindly or there may be an ectopic anus or an anoperineal fistula thatopens into the perineum . Te abnormal canal may, however, open into the vagina in emales or the urethra in males .

Anal Stenosis: Te anus is in the normal position, but the anus and anal canal are narrow .Tis anomaly is probably caused by a slightdorsal deviation o the urorectal septum as it grows caudally to use with the cloacal membrane. As a result, the anal canal and analmembrane are small.

DEVELOPMENTAL ANOMOLIES OF URINARY TRACT (HIGH YIELD FOR 2014)

Horseshoe Kidney: In 0.2% o the population, the poles o the kidneys are used; usually the inerior poles use. Te large U-shapedkidney usually lies in the hypogastrium, anterior to the inerior lumbar vertebrae. Normal ascent o these used kidneys is preventedbecause they are caught by the root o the inerior mesenteric artery. A horseshoe kidney usually produces no symptoms because itscollecting system develops normally and the ureters enter the bladder. I urinary flow is impeded, signs and symptoms o obstructionand/or inection may appear. Persons with urner's syndrome have horseshoe kidneys.

Ectopic Ureter: An ectopic ureter does not enter the urinary bladder. In males, ectopic ureters usually open into the neck o the bladderor into the prostatic part o the urethra, but they may enter the ductus deerens, prostatic utricle, or seminal gland. In emales, ectopicureters may open into the bladder neck, urethra, vagina, or vestibule o the vagina. Incontinence is the common complaint resulting roman ectopic ureter because the urine flowing rom the orifice does not enter the bladder; instead it continually dribbles rom the urethra inmales and the urethra and/or vagina in emales.

An ectopic ureter: Results when the ureter is not incorporated into the trigone in the posterior part o the urinary bladder. Instead it iscarried caudally with the mesonephric duct and is incorporated into the middle pelvic portion o the vesical part o the urogenital sinus.

Cystic Kidney Diseases

In autosomal recessive polycystic kidney disease, diagnosed at birth or in utero by ultrasonography, both kidneys contain manyhundreds o small cysts which result in renal insufficiency.

Multicystic dysplastic kidney disease results rom dysmorphology during development o the renal system .Te outcome or childrenwith multicystic dysplastic kidney disease is generally good because the disease is unilateral in 75% o the cases. In multicystic dysplastickidney disease, ewer cysts are seen than in autosomal recessive polycystic kidney disease and they range in size rom a ew millimetersto many centimeters in the same kidney.

Congenital Adrenal Hyperplasia: (CAH) An abnormal increase in the cells o the suprarenal cortex results in excessive androgenproduction during the etal period. In emales, this usually causes masculinization o the external genitalia .Affected male inants havenormal external genitalia, and the syndrome may go undetected in early inancy. Later in childhood in both sexes, androgen excess leads

to rapid growth and accelerated skeletal maturation. CAH is a group o autosomal recessive disorders that result in virilization o emaleetuses.

DEVELOPMENTAL ANOMOLIES OF GENITAL SYSTEM

Mesonephric Duct Remnants in Males

Te cranial end o the mesonephric duct may persist as an appendix o the epididymis, which is usually attached to the head o theepididymis Caudal to the efferent ductules, some mesonephric tubules may persist as a small body, the paradidymis.

Mesonephric Duct Remnants in Females

Te cranial end o the mesonephric duct may persist as an appendix vesiculosa. A ew blind tubules and a duct, the epoophoron,correspond to the efferent ductules and duct o the epididymis in the male. Te epoophoron may persist in the mesovarium between the




ovary and uterine tube. Closer to the uterus, some rudimentary tubules may persist as the paroophoron. Parts o the mesonephric duct,corresponding to the ductus deerens and ejaculatory duct, may persist as Gartner's duct cysts between the layers o the broad ligamentalong the lateral wall o the uterus and in the wall o the vagina.

Paramesonephric Duct Remnants in Males

Te cranial end o the paramesonephric duct may persist as a vesicular appendix o the testis, which is attached to the superiorpole o the testis.

Te prostatic utricle, a small saclike structure that opens into the prostatic urethra, is homologous to the vagina.

Paramesonephric Duct Remnants in Females

Part o the cranial end o the paramesonephric duct that does not contribute to the inundibulum o the uterine tube may persist as a vesicular appendage

Cryptorchidism or Undescended estes

Cryptorchidism (Greek, kryptos, hidden) occurs in up to 30% o premature males and in approximately 3% to 4% o ull-term males. Tisreflects the act that the testes begin to descend into the scrotum by the end o the second trimester. Cryptorchidism may be unilateralor bilateral. Cryptorchid testes may be in the abdominal cavity or anywhere along the usual path o descent o the testis, but they areusually in the inguinal canal

Ectopic estes: Afer traversing the inguinal canal, the testis may deviate rom its usual path o descent and lodge in various abnormallocations:

Interstitial (external to aponeurosis of external oblique muscle)

In the proximal part of the medial thigh

Dorsal to the penis

On the opposite side (crossed ectopia)

Exstrophy o the bladder results rom a rare ventral body wall deect through which the posterior wall o the urinary bladder protrudesonto the abdominal wall. Epispadias is a common associated anomaly in males; the urethra opens on the dorsum o the penis.

EMBRYOLOGY OF NERVOUS SYSTEM

Te nervous system develops rom the neural plate which appears at the beginning o the third week as thickening o the ectoderm.

Its lateral edges soon elevate to orm the neural olds.

With urther development, the neural olds continue to elevate, and orm a tube known as neural tube, Te neural tube has an enlarged cranial part that orms the brain, and a narrow caudal part that becomes the spinal cord.

Te wall o the neural tube at first has a single layer o cells. Tey multiply and orm three layers- ependymal, mantle and marginal layer.

Neural tube closure begins at cephalic end. AI 2009

Te mantle layer divides into a:

Ventral part, the basal lamina, and

Dorsal part, the alar lamina, separated by a groove, the sulcus limitans.

Alar plate gives rise to sensory areas o the spinal cord and the sensory nuclei

Basal plate orms the motor areas o the spinal cord and motor nuclei. Te cerebellum and its nuclei develop rom the dorsal parts o the alar plate.

Inerior olivary and Substantia nigra are sensory nuclei and thus derived rom the alar plate.

Hypoglossal is a motor nuclei and develops rom the basal plate.




THE WALL OF THE SPINAL CORD

NEUROEPITHELIAL LAYER MANTLE LAYER MARGINAL LAYER

• These cells extend over the entire thickness of

the wall & form a thick PSEUDOSTRATIFIED

EPITHELIUM

• Once the neural tube closes,

neuroepithelial cells begin to

give rise to another cell type.

• The outermost layer of the

spinal cord ,the marginal layer,

contains nerve bers emerging

from neuroblasts in the mantle

layer.

• Junctional complexes at the lumen connect them • These cells are characterized

by a large round nucleus

with pale nucleoplasm & a

dark- staining nucleolus.These

are primitive nerve cells, or

NEUROBLASTS.

• As a result of myelination of

nerve bers, this layer takes

on a white appearance &

therefore is called the White

matter of the spinal cord.

• After closure of neural tube,they divide

rapidly,producing more & more neuroepithelial cells

• They form the mantle layer, a

zone around the neuroepithelial

layer.The mantle layer later

forms the gray matter of the

spinal cord.

Forebrain

(Prosencephalon) Telencephalon

Diencephalon

Cerebral

hemispheres

Thalamus

Hypothalamus

Posterior Pitutary

Pineal body

Mid Brain

(Mesencephalon) No division Tectum

Hind brain

(Rhombencephalon) Metancephalon

Cerebellum

Myelencephalon

Pons

Medulla JKBOPEE 2012

Remainder of neural Tube No division Spinal cord

3 rd ventricle develops rom diencephalon. Orissa 2005

4 th ventricle develops rom rhombencephalon Orissa 2005

MYELINATION

Myelin is ormed in the central nervous system by oligodendrocytes. UPSC 01

Tere are no myelinated fibers in the CNS beore the end o the fifh etal month.

Tere is no myelination o the orebrain until the seventh etal month. Most myelination in the telencephalon occurs in the third trimesterand postnatally.

Te first neurones to acquire myelin sheaths are the olactory, optic and acoustic cortical areas and the motor cortex (pyramidalcells).

Te last to be myelinated are the projection commissure and association neurones o the cerebral hemispheres




Myelination is a critical process or the development o the brain because it enhances the speed o neural communication. It occurs mostrapidly during the first 2 years o lie, but continues until early adulthood

In CNS Myelin is Produced by Oligodendrocyte

A single o ligodendrocyte myelinates as many as 20 or 30 di fferent CNS axonal segments, each over a length of 1

mm or less. DNB 2011

Oligodendrocyte membrane extensions wrap around the axons in a concentric fashion to form the myelin sheath. Myelinproteins include proteolipid protein, myelin basic protein, myelin-associated glycoprotein, and a number of less abundant

proteins detectable by electrophoretic separation.

Active myelin synthesis starts in utero and continues for the rst 2 years of life; slower synthesis continues during childhood

and adolescence.

Congenital Anomalies Associated with Spinal Cord

Spina bifida: Te original deect lies in the vertebrae when their laminae ail to cover the spinal cord dorsally. Spina bifida may be

simple or complicated. Complicated Spina bifida is associated with involvement o the cord and its membranes. Rarely do the two halves o the vertebral body ail to use and the spinal cord protrudes anteriorly through the gap. Tis rarity is called

as anterior spina bifida

Spina bifida occulta: Here the spinal cord is normal. Te deect is not maniest externally and usually a tuf o hair is present onthe skin over the affected area.

Meningocele: Te Arachnoid and the Piamater covering the spinal cord protrude through the opening o the bifid spine and orma cystic swelling.

Meningomyelocele: Here the spinal cord along with its meninges and the spinal nerves are seen to protrude. It is a more seriouscondition owing to development o inection o the cord itsel.

Tis condition is associated with displacement o medulla and a part o cerebellum which cause obstruction o the oramen magnumproducing hydrocephalus. An association o hydrocephalus and Meningomyelocele is called Arnold Chiari malormation.

Syringomyelia: Once the central canal o the spinal cord is distended with excessive fluid it is called Syringomyelia

Myelomalacia: Abnormal sofening o spinal cord. Usually seen afer trauma to spinal cord.

Neural Tube Defect (High Yield for 2014)

Tey are two types o Open and Close

Open Neural Tube Defects

Occur when the brain and/or spinal cord are exposed at birth through a deect in the skull or vertebrae Examples:

anencephaly,

encephaloceles,

hydranencephaly,

iniencephaly,

schizencephaly,

spina bifida.

Closed Neural Tube Defects

Occur when the spinal deect is covered by skin. Common examples o closed

Lipomyelomeningocele,

Lipomeningocele,

ethered cord.




Detection is by

Ultrasound examination

Measurement o maternal serum alpha-etoprotein (MSAFP).

Amniotic fluid acetylcholinesterase (AFAChE)

SYRINGOMYELIA

In Syringomyelia there is sofening o the spinal cord and the central canal becomes very wide at lesion in this position will interrupt thepain and temperature fibres which pass in ront o the central canal as they cross rom one side to another.

Syringomyelia usually occurs in the lower cervical and the upper thoracic regions o the spinal cord and the loss o pain and tempera-ture.

Only the fibres o the pain and temperature which pass in rom o the central canal are injured: the lateral spinothalomic tracts “themselves”remain normal and there is no loss o pain and temperature in the lower limbs.

ouch can be elt in the area o the skin in which pain and temperature are lost: this condition in which pain and temperature is lost whiletouch is nearly normal called Dissociated sensory loss.

HISTOLOGY/ MICROANATOMY

Important changes in Phases of Cell Cycle

Leptotene: Chromosomes become visible

Zygotene: Pairing of Chromosomes

Pachytene: Tetrad formation, Crossing over, Chiasmata formation JK BOPEE 2009

Diplotene: Chromosomes break

Metaphase: Spindle formation

Anaphase: Chromosomes move from equator to poles

Telophase: Chromosomes move completely to opposite sides

SEX CHROMATIN OR BARR BODY

O the two X-chromosomes in a Female only one is unctionally active. Te other (Inactive) X-chromosome orms a mass o hetero-chromatin that lies just under the nuclear membrane. Tis mass o heterochromatin can be identified in suitable preparations and canbe useul in determining whether a particular tissue belongs to a male or a emale. Because o this association with sex this mass oheterochromatin is called the SEX CHROMAING. It is also called a BARR-BODY afer the name o the scientist who first discoveredit.

In NEURONS it forms a rounded mass lying very close to the nucleolus and is therefore called a NUCLEOLAR SATELLITE.

In NEUROPHIL LEUCOCYES it may appear as an isolated round mass attached to the rest of the nucleus by a narrow band, thus

resembling the appearance of a DRUM-SICK. Rarely, some individuals may have more than two X-chromosomes. In these cases

only one X-chromosome is active (and hence euchromatic) while others are represented by masses of heterochromatin.

In normal females XX: there is one barr body.

there is no barr body.

there is no barr body.

there is one barr body.

there are two barr bodies. MAHE 1998

In normal males XY:

In Turners Syndrome XO:

In males with Klienlters syndrome XXY:

In super female XXX,

The number of Barr bodies is (X-1)




Fixatives Used in Histology

Formaldehyde

Mercuric chloride

Potassium dichromate

Picric acid

Dehydrating Agents Used in Histology

Alcohol

Clearing Agents Used in Histology

Chloroorm

Xylene

Important Stains Used in Histology (High Yield for 2014)

H&E Stain (Haematoxylin and Eosin). Haematoxylin , a natural dye product, acts as a basic dye that stains blue or black.

Nuclear heterochromatin stains blue and the cytoplasm of cells rich in ribonucleoprotein also stains blue.

The aniline dye, Eosin, is an acid dye that stains cytoplasm, muscle, and connective tissues various shades of pink and

orange. This difference in staining intensity is useful in differentiating one tissue from another.

Vital Stain: such as Indian ink, l ithium carmine, Neutral red, Trypan blue are used for staining living cells such as

Reticulo endothelial cells.

Metachromatic Stains: are used for staining mast cells with Touidine blue. The stains react with granules of mast cells

(metachromasia) to give a new color to the cells

Periodic Acid-Schiff Method (PAS) Principally used to demonstrate structures rich in carbohydr ate macromolecules

such as glycogen, glycoprotein, and proteoglycans found in ground substance of connective tissues, basement

membranes and mucus.

Phosphotungsti c Acid Haematoxylin (PTAH) This is an ideal stain for the demonstration of striated muscle bers andmitochondria, which stain blue.

Silver Stains Certain tissue components called Argyrophilic have a natural afnity for silver salts. Reticular bers and

the granules in diffuse endocrine cells are argyrophil ic.

Sudan Stains Sudan dyes are used to stain lipids. The Sudan dyes, e.g., Sudan IV, dissolve in droplets containing

triglycerides and color them intensely.

EPITHELIUM High (Yield for 2014)

Simple Squamous Epithelium

Alveoli o lungs Mesothelium o Pleura, Peritoneum and Pericardium PGI 1995

Endothelium o Heart and Blood Vessels

Simple Cuboidal Epithelium

Lining o the Tyroid ollicles

Germinal epithelium o ovary

Anterior surace o lens o eye




Simple Columnar Epithelium

Te lining o Stomach

Intestines

Gall bladder

Simple Columnar Ciliated

Fallopian tubes and the Uterus

Central canal o Spinal cord.

Osseous part o Eustachian tube

Pseudo stratied Columnar (Pseudo: False, Stratied: Layered)

It is a simple type o columnar cells resting on a clear wavy basement membrane. Te cells are crowded over each other and appear multilayered .Te nuclei are arranged at different levels, some situated basal and others centrally as a result o which a alse impression o multilayered cells is created. However, most o the cells reach the basement membrane. Te cells may be ciliated or non ciliated.

With cilia

Nasal cavity, nasal air sinuses, nasopharynx, larynx, trachea and bronchi RJ 2000

Eustachian tube in its cartilaginous parts.

Without cilia

Vas deferens

Part of male urethra

Stratied Squamous Epithelium

Te surace o the cells may be keratinized (Protective unction) as in case o

Epidermis o Skin

External ear

External nose

Te surace o the cells may be without keratin called Non Keratinized as in case o

• Esophagus

• Tongue

• True vocal cords JK 2009

• Cornea. AP 1991

• Tonsil UP 2008

Stratied Columnar Epithelium

Conjuctival ornicies

Penile part o male urethra

Ano-rectal junction

Transitional Epithelium

It is a type o epithelium composed o multiple cell layers.

Tey have extra reserve o cell membrane. JIPMER 1995




Te op cell layers are broader.

Te intermediate cell layers are polyhedral without intercellular bridges separated by mucus like substance. Te cells can undergotransition in relaxed and contracted state. In the relaxed state the number o layers is 6-8 while as in the contracted state it is 2-3layers.

Te Basal cell layers are Cuboidal.

It is present in :

Calyces AIIMS 2007

Ureter UP 2008

Urinary bladder AIIMS 2007, UP 2007

UV junction JIPMER 1993

Male Urethra

Urothelium

Lines much o the urinary tract, extending rom the ends o the collecting ducts o the kidneys,

Trough renal calyces, pelvis, urethras and bladder to the proximal portion o the urethra. In males it covers the urethra as ar as theejaculatory ducts, then becomes intermittent, finally being replaced by stratified columnar epithelium in the membranous urethra. Inemales it also extends as ar as the urogenital membrane.

Urothelium or ransitional epithelium has the ability to stretch greatly without loosing its integrity. Tus the urinary organs lined byurothelium can undergo considerable distention and contraction.

Important Cells In Histology : (High Yield for 2014)

Stave cells: special cells linning spleenic sinusoids

anycytes: Special cells linning ventricles o brain

Littoral cells: phagocytic cells lining capillaries

Rouget cells: Phagocytic cells lining sinusoids

Bergmann Cells Glial cells of CerebellumGitter cells KERALA 2001 Microglia

Intersititial cells of Cajal Nerve cells of supercial layers of cerebral cortex

Supporting cells of Claudius Cells in oor of Cochlear canal of inner ear

Dieters Cells Outer hair cells of organ of Corti

Hensens cells Supporting cells in organ of Corti external to Dieters cells

Houfbauers Cells AMU 1991 Ellipsoidal cells in chorionic villi of placenta

JG cells ROHTAK 1987 Smooth muscle cells of affarent arteriole.(kidney)

Ito Cells PGI 1999 Stellate cells in liver

Langerhans cells Antigen presenting epithelial dendritic cells

Langhans Cells Cytotrophoblastic cells of chorionic villi

Basket Cells Myoepithelial cells in salivary/mammary/sweat glands

Gitter cells KERALA 2001 Microglia of brain

Basket Cells of Cerebellum Neurons of molecular layer of Cerebellum

Merkel Cells Sensory nerve endings

Muller’s Cells COMED 2005 Neuroglial cells in Retina

Hilus cells Rare cells found in Medulla of Ovary at Hilum of Ovary

Lacis Cells Extra glomerular Mesengial Cells outside Glomerulus

Peg Cells Secretory cells in mucosa of uterine tube

Glomus Cells COMED 2002 present in Carotid Bodies




CONNECTIVE TISSUE CELLS

Undifferentiated mesenchymal cells: give rise to any other type of connective tissue cells

Fibroblasts: involved in repair

Phagocytic cells/clasmatocytes: specically Kuffer cells in Liver, Stave cells in Spleen, Osteoclasts in Bone Mast cells: Involved in Bronchial Asthma and Atopy . Contain Heparin, Histamine

Plasma cells: Undue Proliferation can lead to Myelomas

Melanocytes: Involved in Vitiligio,

Fat cells: Normal Signet Shaperd. Can lead to Development of Lipomas

Important Terms In Histology/MicroAnatomy

Eponyms Description

Bowman's capsule Glomerular capsule of the kidney seen on histology slides

Bowman's membrane Layer in the cornea below epithelium seen on histology slides

Brunner's glands Glands in the duodenum seen on histology slidesBundle of His Atrioventricular bundle

Cords of Billroth Splenic cords of the spleen seen on histology slides

Corpora aranacea Pineal gland

Corpora amylacea Prostate gland

Crypts of Lieberkuhn Epithelial glands in the small intestine seen on histology slides

Descemet's membrane Limiting layer of the cornea seen on histology slides

Ducts of Bellini Papillary duct of the kidney seen on histology slides

Ducts of Luschka Small ducts found in the connective tissue between the gallbladder and the liver

Golgi apparatus Intracellular organelle

Golgi tendon organ Sensory nerve ending embedded in a tendon for proprioception

Graaan follicle Tertiary follicle of an ovary seen on a histology slide

Hassals corpuscle Thymus

Haversian canal Central canal of an osteon of bone seen on a histology slide

Haversian system Osteon of bone seen on a histology slide

Islets of Langerhans Pancreatic islets of the pancreas seen on histology slides

Leydig cells Interstitial cells of the testis

Loop of Henle U shaped loop in the nephron of the kidney

Krause end bulbs Cylindrical/oval sensory receptor

Malpighian corpuscle Renal corpuscle of the kidney seen on histology slides

Meissner's corpuscle Mechanoreceptor

Meissner 's plexus Submucosal plexus

Merkel's disc Tactile receptor

Moll's gland Glands of the conjunctiva

Nissl bodies Rough endoplasmic reticulum of a neuron

Node of Ranvier Rrea between two Schwann cells covering nerve bers with axon which is not covered by

myelin

Organ of Corti Small organ of sound transduction; spiral organ

Pacinian corpuscle Lamellar corpuscle

Peyer's patches Aggregates of lymphatic tissue in the ileum seen on histology slides




Purkinje bers Part of the conducting system of the heart

Renal columns of Bertin Renal columns seen on histology slides

Rufni's corpuscle Sensory receptor

Space of Disse Perisinosoidal space of the liver seen on histology slides

Volkmann's canals Perforating canals of bone

Wharton's jelly Mucous connective tissue seen in umbilical cord

Difference in Histology of Muscles

Points Smooth muscle Skeletal muscle Cardiac Muscle

• SITE in the viscera Around skeleton In the heart

• SHAPE spindle Cylindrical Cylindrical

• STRIATIONS non striated Striated Less marked

• SARCOLEMMA Thin Thick very thin

• SARCOPLASM Pale Red and pale Red

• SIZE Small Large Medium

• BRANCHING No Yes yes and anastomosing

• DIAMETER upto 10 microns upto 80 microns upto 20 microns

• NUCLEI single, central multiple peripheral Central UPSC 2001

• Intercalated DISCS Absent Absent Present COMED 2003

• ACTION Involuntary Voluntary Involuntary

Salivary Glands

Gland Duct Type of Gland Duct opening

• Parotid • Stensons duct • Serous Vestibule of mouth opposite second upper molar

• Submandubular • Whartons duct • Mixed but

predominantly serous

On the oor of mouth on summit of sublingual

applila at the side of frenulum of tongue

• Sublingual • Bartholins duct • Mixed but

predominantly mucus

On the oor of mouth on summit of sublingual papplila

Questions Frequenly asked from Histology of Liver

Classic Hepatic Lobule. Tis model is based on the direction o blood flow. In sections, liver substructure exhibits a pattern ointerlocking hexagons; each o these is a classic lobule. Whereas lobules in pigs are defined by a sheath o connective tissue, there is lessconnective tissue in humans and the lobule boundaries are indistinct. Te central vein at its center, and the alternating hepatocyte plates

and sinusoids that lie between them. Portal Canal /triad. One triad occupies a potential space (portal space) at each o the 6 corners o the lobule. Each triad contains 3 main

elements surrounded by connective tissue: a portal venule (a branch o the portal vein), a hepatic arteriole (a branch o the hepaticartery), and a bile ductule (a tributary o the larger bile ducts). A lymphatic vessel may also be seen. In the portal canal blood vessels andbile ductules are separated by a space called as Space o Mall

Portal lobule. Tis model is based mainly on the direction o bile flow, which is opposite to that o blood. From this perspective, the liverparenchyma is divided into interlocking triangles, each o which has a portal triad at the center and a central vein at each o its 3 comers.

Hepatic lobule: It is the structural unit o liver .It has a Central vein. A single vein marks the center o each lobule. Tis vessel is easilydistinguished rom those in the portal triad by its larger opening and lack o a connective tissue investment.

Kuffer cells are Reticuloendothelial cells o liver. Kerala 2000

Itto cells are at storing cells in liver.

“Space o Dissie” and “Space o Mall” are seen in Liver. JK BOPEE 2006




IMPORTANT HISTOLOGICAL FEATURES

Hassals corpuscles Thymus MAH 2012

Corpora amaylacea Prostate

Corpora atretica Ovary

Germinal centre Lymph node

Corpora aranacea Pineal gland

Herring bodies Pituitary gland

Cords of Billiroth Spleen

Cells in Skin are: High Yield for 2014

“Langerhans Cells”

Are located primarily in the stratum spinosum.

Tey unction in the immune system as antigen presenting cells.

Tey stain selectively with gold chloride and contain numerous rod like or racket-shaped Cytoplasmic granules (Birbeck's granules).

“ Merkel cells”

Are located in the stratum basale.

Tey contain granules which contain catecholamines.

Te base o a Merkel cell makes contact with the expanded terminal disk o a nerve fiber, orming a special receptor which unctions asa mechanoreceptor (detection o touch).

“ Dendritic cells”

Are ound throughout the epidermis.

Tey are antigen presenting cells

CELLS OF STOMACH

The Mucus neck cells JKBOPEE 2012

• Called so as they are present in the necks of glands

• They secrete mucin which serves as a protective layer against HCL.

• They appear pale because of dissolved mucin.

• They are low columnar with basal at nuclei.

The Chief cells (The Peptic cells o r the Zymogen cells)

• Called as chief because they line the main part of the body of the gland. AI 2009

• They are low columnar with basal round nuclei.

• They secrete pepsinogen

Oxyntic cells (parietal cells )

• They are scattered in between peptic cells.

• They are highly acidophilic.

• Intrinsic factor of Castle is secreted by parietal cells AI 2009

• They secrete HCL.

• They contain secretory canaliculi and are rounded.

The Argentafn cells

They are chromafn Positive and stain positive with Silver salts.

They also contain acidophilic granule s and are oval in shape.




Cells of Intestine

Simple Columnar cells

Line the villi and crypts

Have free brush border due to presence of microvilli to increase surface area.

Goblet Cells

Are also present in the villi and crypts

They are unicellular glands.

They are ask shaped.

They secrete mucin

Paneth Cells

Are acidophilic

Secrete intestinal enzymes

Rich in Rough ER AI 2009

Argentafn cells

These are cells with silver staining properties

They secrete serotonin.

Cells of Trachea

Te trachea is composed o

Pseudostratified columnar ciliated cells goblet cells ,and basal cells .

Basal cells are capable o differentiating into goblet or ciliated cells.

Other cells making up the epithelium include

Brush cells,

Serous cells, and

Kulchitsky cells.

Diffuse lymphatic tissue, isolated lymphatic nodules: (High Yield for 2011/2012)

The Diffuse lymphatic tissue is a collection of lymphatic tissue in

• Alimentary tract

• Respiratory tract

• Genito-urinary tract

• The lymphoid tissue is deposited randomly in the sub epithelial layers and placed strategically so as to

detect and destroy the pathogenic agents instantaneously and effectively. Located in adventitia.

AI 2009

Functioning in close collaboration is other set of localized concretions of lymphocytes in the form of folliclesand nodules such as

• Pharyngeal tons ils

• Palatine tonsil s

• Lingual tonsils

• Peyers patches In the small intestine especially in the ileum

• Lymphoid follicles in appendix/abdominal tonsil

In the alimentary canal the diffuse and the local lymphatic systems combine synergistically to form the GUT

ASSOCIATED LYMPHOID TISSUE (GALT). The main function of this system is to act along with the main lymphatic

organs




CELLS OF TESTIS (HIGH YIELD FOR 2014)

Sertoli cells are known as the Supporting cells o estis.

Tese are derived rom the mesoderm.

Tese elongated, branched, pyramidal epithelial cells are scattered in between spermatogenic cells. Sertoli cells have a well developed SER and Golgi complex, numerous mitochondria, and some RER.

Te unctions o the Sertoli cells include

Support or the spermatogenic cells, which attach to one another by Cytoplasmic bridges

Nutritional regulation o the developing spermatozoa, which are isolated rom the blood supply by the occluding junctionsbetween the supporting cells. Spermatozoa thereore depend on these cells to mediate the exchange o nutrients and metaboliteswith the blood

Protection rom autoimmune attack by immunoglobulins in the blood

Scavenger Cells help in Phagocytosis o residual bodies shed by the maturing spermatozoa; and

Secretion o fluid or sperm transport

Leydig Cells

• Also known as interstitial cells o Leydig, are endocrine cells of testis found adjacent to the semineferous tubules in the

testicle. Leydig cells have round vesicular nuclei and a granular eosinophilic cytoplasm. Leydig cells are named after the

German anatomist Franz Leydig, who discovered them in 1850.

• Leydig cells release a class of hormones called androgens (19-carbon steroids). They secrete testosterone,

androstenedione and dehydroepiandrosterone (DHEA), Frequently Lipofuscin pigment and rod-shaped crystal-like

structures (Reinke's crystals) are found in them.

CELLS OF NERVOUS SYSTEM

Microglia: (Micro: small), these cells are also called as CNS Macrophages and their unction is mainly phagocytosis. Tey show amoeboidmovements in response to tissue damage. Tey have got an irregular outline .Te nucleus is small and the cytoplasm is scanty. However theyposses large numbers o lysosomes.

Astrocytes : (Astro: Star shaped). Tere are two types o astrocytes.

Protoplasmic astrocytes

Fibrous astrocytes

Protoplasmic Astrocytes

Tey are stellate shaped cells with arborisation. In contrast to Microglia, these cells have a larger nucleus and abundant cytoplasm. Distributionis mainly confined to the grey matter.




Fibrous Astrocytes

Tese cells are different rom protoplasmic astrocytes in that they have a higher concentration o fibrillary structures in the orm o filamentsin their cytoplasm. Te nucleus has the same characters as that o protoplasmic astrocytes. Distribution is to the white matter o the CNS.

Functions

They form the structural support for the neurons.

They form an integral element of the Blood Brain Barrier.

They help in repair by partial phagocytic action

Oligodendroglia: (oligo: few, Dendron: tree)

Tey have ewer processes with ewer branches.

Tey are smaller as well with smaller nuclei.

Tey are predominantly seen in the white matter o the CNS. Based on their location they are named as:

Perineuronal (along neural tissue)

Perivascular (along vascular tissue)

Interascicular (distributed between nerve fibres)

Teir unction is mainly to myelinate CNS neurones.

Secondary unctions believed to be attributed to them are to provide nutrition to the neurones and to regulate the metabolism o neurons bymechanisms yet not understood ully.

Ependymal Cells: High Yield for 2014

Tese cells are different in that they line the ventricles o the brain and the central canal o the spinal cord. Tey have the characteristicso the squamous type o epithelium and possess microvilli on their ree surace which acilitates the movement o CSF.

Tese cells secrete substances into the CSF or absorb substances rom the CSF.

At places in the walls o the third ventricle and sometimes in the ourth ventricle it has been seen that the Ependymal cells somehow aretaller and hence assume the shape o columnar type epithelium. Tese cells are called as “tanocytes”. Tey are normally present in lower vertebrates. Teir staining characters are different and it is believed that these cells have a role in secretion MOSLY.

Tey are believed to assist in secretion o CSF, secretion o neurochemicals into CSF, and a role as chemo receptors.

Types of RETICULO ENDOTHELIAL CELLS in various ORGANS

Bone Marrow: Reticular cells in bone marrow are phagocytic. Tey are primitive branched ree cells which can change into Histiocytes.

Osteoclasts in Bone: Tey are large, multinucleated, irregular cells with acidophilic cytoplasm.

Microglia in CNS: Tey are mesodermal in origin with multiple dendrites but no axons and no Nissl granules

Blood Histiocytes are the phagocytic cells in the blood stream.

Spleen: Te phagocytic cells o spleen are the Histiocytes, Reticular cells and the Littoral cells lining the walls o the blood sinusoids.

Blood capillaries: Te walls o the blood capillaries are lined by specialized phagocytic cells called as the Rouget cells Liver: Te Kuffer cells in the blood sinusoids o liver are branched, basophilic phagocytic cells.

Lung: Te alveoli o the lungs contain the Dust cells or alveolar macrophages and the Heart Failure cells. Dust cells engul the dustparticles and the heart ailure cells engul the blood cells in case o heart ailure.

Connective tissue: Te phagocytic cells o the connective tissue also called as clasmatocytes, macrophages, Histiocytes, tissue cells,rhagiocrine cells, pyroll cells, resting wandering cells, adventitial cells. Tey acquire motility in response to inflammatory stimuli.




UPPER LIMB

BRACHIAL PLEXUS

C5 and C6 roots join to orm the upper trunk C7 root alone orms the middle trunk

C8 and 1 roots join to orm the lower trunk

Each trunk divides into an anterior and posterior division

All the posterior divisions join to orm the posterior cord

Te upper two anterior divisions join to orm the lateral cord

Te lowest anterior division alone orms the medial cord

Branches of the Brachial Plexus

Branches from the Roots

Nerve to serratus anterior (C5, C6, C7)

Dorsal scapular nerve (C5)

Muscular branches to the 3 scalene muscles

Branches from the trunks

Suprascapular nerve (C5, C6) AIPGME 2011

Subclavius nerve (C5, C6) AIPGME 2011

Branches from the cords

Medial cord

Medial head o median nerve (C8, 1)

Medial pectoral (C8, 1)

Ulnar nerve (C8, 1)

Median cutaneous nerve o orearm (C8, 1)

Median cutaneous nerve o arm (1)

Lateral cord

Lateral pectoral (C5, C6, C7)

Lateral head o median (C5, C6, C7

Musculocutaneous (C5, C6, C7) TN 2007

Posterior cord

Radial (C5, C6, C7, C8, 1)

Axillary (C5, C6)

Nerve to latissimus dorsi (C6, C7, C8)

Subscapular Upper (C5, C6) DNB 2001

Subscapular lower

Erbs Palsy

Lesion o upper trunk o Brachial plexus (C5, C6) caused by oreceul downward traction o shoulder with lateral displacement o headto the other side.




The Deformi ty Causes

Extension o elbow

Flexion o wrist.

Hanging o arm by the side. Pronation o orearm

Klumpkes Palsy

Lesion o lower trunk o Brachial plexus (C8 ,1) caused by oreceul upward traction o the arm, Te deormity causes:

Claw hand

Horners Syndrome

Sensory loss on ulnar side o orearm

Crutch Palsy

Damage o brachial plexus in the Axilla rom pressure o the Crutch as a result o damage o Radial nerve .

High Yield Facts about Scapula: (High Yield fo r 2014)

Winging scapula Injury to thoraxic nerve of Bell. Prominence of medial border of scapula.

Pulsating scapula In coarctation of aorta, dilatation and tortusity of collaterals around scapula occurs

Fracture scapula Due to violent trauma

Sprengels deformity Scapula remains elevated. failure of descent.

Klippel feil deformity Bilateral failure of descent of scapula. Webbing of neck and limitation of nck movements due to failure

of fusion of occipital bone and cervical spine defects is a feature

Anastomosis Around the Scapula

A rich anastomoses exists around the scapula between branches o subclavian artery (first part) and the axillary artery (third part). Tisanastomoses provides a collateral circulation through which blood can flow to the limb when the distal part o subclavian artery or theproximal part o axillary artery is blocked.

Anastomosis around the scapula:

Formed by branches o :




Subclavian artery- First part

Suprascapular artery

Deep branch o transverse cervical artery

Axillary artery-third part

Subscapular artery & its circumflex scapular branch

Anastomoses over the Acromion Process

Formed by:

Acromial br. o thoraco-acromail artery

Acromial br. o suprascapular artery.

Acromail br. o posterior circumflex humeral artery

Te subscapular artery also orms anastomoses with intercostals arteries.

Axil lary Artery And i ts Branches

Ist Part: gives (1)

Superior thoracic artery.

2nd Part : gives (2)

Toracoacromial and Lateral thoracic arteries

3rd Part : gives (3)

Anterior circumflex humeral , Posterior circumflex humeral and Subscapular arteries

Movements at Shoulder joint: (High Yield for 2014)

Shoulder joint is weak ineriorly. Kerala 2009

Flexion Clavicular head of pectoralis major, anterior bres of deltoid UPSC 2008

Extension Posterior bres of detoid, latismus dorsi

Adduction Pectoralis major, latismus dorsi

Abduction Deltoid,supraspinatus, serratus anterior, trapezius

Medial rotation Pectoralis major, anterior bres of deltod,latismus dorsi, teres major

Lateral rotation Posterior bres of deltoid, infraspinatus, teres minor.

Remember

NERVE SUPPLY OF

Dorsal scapular nerve • Rhomboids

Long thoraxic nerve • Serratus anterior

Suprascapular nerve • Supraspinatus, infraspinatus DNB 2007

Lateral pectoral nerve • Pectoralis major

Medial pectoral nerve • Pectoralis major, pectoralis minor




Actions of

• Lumbricals and interossei Flexion at MP joints, extension at IP Joints

•Palmar interossei Adductors

• Dorsal interossei Abductors

Erbs palsy/Policemans tip hand /Porter’s tip position o upper limb is the result o injury to Upper trunk o brachial plexus

Erb’s point is at union o: C5-C6 (MP 2006)

Klumpkes palsy is the result o injury to lower trunk o brachial plexus (MP 2009)

Te anterior rami o five spinal nerves, C5, C6, C7, C8, and 1 (C4 and 2 may also contribute to the brachial plexus), exit through theintervertebral oramina and orm trunks that pass through the scalene triangle and then divide behind the clavicle. Te divisions othe trunks reunite to orm cords that surround the axillary artery as it passes behind the pectoralis minor tendon. Te division o these

cords into the major motor and sensory nerves o the upper extremity usually occurs distal to the pectoralis minor tendon. Rami rom C8 and 1 orm the lowest trunk, which lies on the first rib behind the subclavian artery and is responsible or the groove

in the rib (which is ofen attributed to the artery). Te peripheral distribution o C8 and 1 fibers provides sensory perception romthe fifh finger and medial hal o the ourth finger and rom the medial aspect o the orearm. AIPGME 2012

Remember

FREQUENTLY ASKED QUESTIONS FROM NERVES OF UPPER LIMB

Ulnar Nerve “ Musicians Nerve”

Ulnar nerve supplies medial 1/3 o palm. (Hypothenar area) AIIMS 2007

Ulnar nerve in hand supplies: 3, 4 Lumbricals,

Palmar and dorsal interosei, UP 2006

adductor pollicis, UP 2006

hypothenar muscles.

Ulnar nerve in hand supplies flexor carpi ulnaris and medial hal o flexor digitorum proundus.

Lesion o ulnar nerve causes:

weakness o ulnar deviation

weakness o wrist flexion

adductor pollicis paralysis with loss o thumb adduction PGI 2007

In Ulnar Nerve Palsy There is: (High Yield for 2014)

Positive Card test

Positive Book test/Froment sign PGI 2007

Positive Egawas test

Ulnar Claw hand UP 2006

MEDIAN NERVE: “ LABOURERS NERVE”, EYE OF HAND

Does not supply arm.




Supplies all flexors except Flexor carpi ulnaris and medial hal o flexor digitorum proundus in orearm

Supplies thenar eminence. AIIMS 2002

Lumbrical 1 and 2,

Opponens pollicis,

Abductor pollicis brevis, Flexor pollicis brevis in hand. (LOAF).

Implicated in :

Lunate dislocation. PGI 2000

MEDIAN NERVE DEFORMITY CAUSES

Ape thumb deformity AI 2000

Carpal tunnel syndrome

Pointing index

Pen test is positive in median nerve injury

Loss of opposit ion and abduction of thumb

RADIAL NERVE

Supplies

extensor compartment of arm, forearm

triceps,

anconeus and extensors of forearm. Extension o f MCP joint AIIMS 2K

Injury to RN Causes:

Wrist drop.

Saturday night palsy/ crutch palsy

Commonly injured in Radial groove

In Saturday Nnight Palsy

The nerve is damaged during sleep in a drunkard in whom the arm has been placed over the back of a chair.The triceps is

usually spared but the weakness conspicuous in the wrist and nger extensors,brachioradialis and supinator.Sensory loss is

slight.




CUBITAL FOSSA

Is a triangular space which lies in ront o the elbow.

Base lies above

Apex lies below

Is bounded above by an imaginary line between medial and lateral epicondyles o humerus.

Laterally: Brachioradialis muscle Medially: Pronator teres muscle

Apex is ormed by the meeting o both the lateral and medial borders

Roo is ormed by:

Skin

Superficial ascia contains cephalic vein, basilica vein, median cubital vein, medial cutaneous nerve o the arm and lateral cutaneousnerve o the orearm.

Deep ascia is pierced by the communication between deep veins and median cubital vein.

Bicipital aponeurosis.

Floor is ormed by brachialis and anterior part o supinator muscle.

Contents of fossa (High Yield for 2014)

Median nerve which disappears between two heads o pronator teres.

End o brachial artery.

Origin o radial artery.

Origin o ulnar artery.

Biceps tendon.

Beginning o posterior interosseous nerve.

Supratrochlear lymph nodes.




COMMON QUESTIONS IN SURGICAL ANATOMY (HOT QUESTIONS)

In “sup ra condylar fracture” of humerus triangular relationship of th ree bony prominences is not distur bed. In elbow

dislocation it is disturbed.

The “ shoulder joint” i s the most commonly dislocated major joint in the body.

MC dislocation is inferior MP 2008

In subacromial bursitis, person feels pain when arm is abducted. “Dawbarns sign” is seen in subacromial bursitis.

PIN (Posterior interosseous nerve) is a branch of radial nerve. No wrist drop is seen in injury to PIN.

If posterior medial aspect of elbow is banged against a hard object, it mat cause temporary ulnar nerve damage. this may result

in painful tingling sensations along ulnar aspect of forearm and hand.Because of these sensations, this area of elbow is called

“ Funny bone/ Crazy bone”.

Eye of hand: median nerve. enables the indiviual to feel thinness and texture of cloth.

Pronator syndrome: compression of Median nerve between two heads of pronator teres.

Infection of pulp spaces is Felon/ Whitlow.

Palmar aponeurosis (High Yield for 2014)

It is the deep ascia o palm and is the continuation o palmaris longus. lips Into our s It has three parts the lateral, medial and the centralparts. Te base o the central part divides into medial our slips and each slip divides into superficial and deep parts.

Te superficial part uses with the superficial transverse ligaments o the palm.

Te deep part divides into two parts and they are attached into

Deep transverse ligament o palm

Proximal and middle phalanx

Continuous with fibrous flexor sheaths

Dupytren’s Contracture

Is the inflammatory contracture o the palmar aponeurosis, characterized by fixing o the proximal and middle phalanx but the terminal

phalanges are not involved. Te ring finger is commonly affected.

Carpal Tunnel

Is the passage ormed by concavity o carpal bones bridged by flexor retinaculum. Te structures passing deep to it are:

Median nerve

Ulnar bursa containing flexor digitorum superficialis and proundus.

Radial bursa containing flexor pollicis longus

Flexor carpi radialis

inels sign: Percussion o median nerve gently at wrist causes tingling sensation radiating into hand.

Wrist flexion test (Phalens sign): Exacerbation o symptoms when patient is asked to flex wrist. Symptoms disappear as wrist isstraightened.

Eliciting inels Sign




PRONAOR SYNDROME

This is the uncommon entrapment neuropathy of median nerve.

Can occur as nerve passes:

Deep to biceps aponeurosis Between two heads of pronator teres

Through a brous arch of exor digitorum supercialis

Clinical f eatures:

Pain & tenderness in proximal aspect of anterior fore-arm

Symptoms often fol low activit ies that involve repeated elbow movements.

Weakness of all muscles innervated by median nerve including abductor pollicis brevis and long nger

exors.

Sensory impairment on palm.

POSTERIOR INTEROSSEOUS NERVE PALSY (HIGH YIELD FOR 2014)

Entrapment Neuropathy of Posterior Interosseous Nerve

It is seen within orearm extensors.

No sensory impairment as superficial radial nerve arises above this level.

Radial wrist extensors & brachioradialis are normal.

Extensor carpi ulnaris is usually affected – Attempted wrist extension causes radial deviation.

Branches to ECRB & supinator may arise rom main trunk o radial nerve (above arcade o Frohse) where entrapment occurs.

Tis is characterized by weakness o

Finger extension

Tumb extension & abduction

INJURY TO SUPRASCAPULAR NERVE

Causes:

Neuralgic amyotrophy

Entrapment neuropathy in scapular notch

Damage due to trauma to scapula and shoulder

Features:

Pain in shoulder

Wasting and weakness of supraspinatus & infraspinatus.

Te Axillary nerve is a branch o the posterior cord o the brachial plexus.

It is particularly susceptible to the injury in shoulder dislocations that displace the humeral head or in racture o the surgical neck othe humerus.

A poorly placed crutch (Crutch Palsy) may also damage this nerve causing paralysis o the eres minor and Deltoid muscles.PGI 2006

Arm abduction is impaired and there is associated loss o sensation over the lower hal o the deltoid. KCET 2012

Te Lower Subscapular nerve innervates the eres major, which is responsible or adducting and medially rotating the arm,it is abranch o the posterior chord (C5 C6) o the brachial plexus. MAH 2005

Te Suprascapular nerve innervates the Supraspinatus and Inraspinatus muscle, that are responsible or abduction and lateral




rotation o the arm. the nerve is derivated rom the C5 & C6 nerve roots.

In shoulder abduction:

Humerus elevates

Clavicle rotates

lateral rotation o scapula occurs along with acromioclavicular joint movement. AI 2010

Te Troacodorsal nerve innervates the latissimus dorsi muscle, that is responsible rom adduction and extension o the arm. Tenerve arises rom the posterior chord (C5, C6, C7) o the brachial plexus

Musculocutaneous nerve supplies (BBC) biceps, brachialis, corocabrachialis. PGI 2006

Brachioradialis is supplied by radial nerve.

Action of Various Muscles of Upper Limb: (High Yield for 2011/2012)

Flexors of forearm: Biceps, brachialis, brachioradialis. PGI 2006

Extensors of arm: Triceps, Anconeus,

Muscles attached to greater tubercle: Supraspinatus, infraspinatus, teres minor. PGI 2005

Muscles attached to lesser tubercle: subscapularis.

Muscles attached to coracoid process: short head of biceps. PGI 2005

Abductors of shoulder joint: Deltoid , serratus anterior, trapezius PGI 1997

Adductors of shoulder joint: pectoralis major, lattismus dorsi

REMEMBER: (HIGH YIELD FOR 2011/2012)

Musculocutaneous nerve Muscles of anterior compartment of arm

Supplies Biceps, corocabrachialis, brachialis.

• Injury causes loss of elbow exion and weakness in

supination.

Median nerve Muscles of anterior compartment of fo rearm

Injury to median nerve at wrist causes:

• Ape thumb deformity.

• Pen test for abductor pollici s brevis

• Inability to count on ngers with thumb.

Axil lary nerve Deltoid and teres minor

Injury causes:

• Loss of abduction o f shoulder.

• Rounded contour of shoulder is lost.

• Sensory loss over lower half of deltoid.

Fracture surgical neck of

humerus dislocation of

shoulder

Radial nerve Posterior muscles of arm and forearm

• Injury causes

• Saturday night palsy

• Crutch palsy

• Wrist drop

Fracture of humeral shaft

Remember




Students Elbow

Tere is inflammation o subcutaneous olecranon bursa which causes a round, fluctuating, and painul swelling o about 1 inch over olecranon.

Tennis elbow: (High Yield for 2014) Tis is due to inflammation o tissues surrounding lateral epicondyle o humerus.

It is the most common cause i elbow pain in orthopaedic OPD.

Golfers Elbow

Tere is inflammation in region o medial epicondylePain and tenderness over anterior aspect o medial epicondyle. Pain is aggravated byputting flexor tendons on stretch by orcible extension o wrist while patient flexes it.

The ‘Anatomical Snuffbox’ (High Yield for 2011/2012)

Triangular depression formed on the posterolateral side of the wrist and metacarpal I by the extensor tendons passing

into the thumb. Historically, ground tobacco (snuff) was placed in this depression before being inhaled into the nose.

Te base o the triangle is at the wrist and the apex is directed into the thumb. Te impression is most apparent when the thumb isextended: The lateral border is formed by the tendons of the abductor pollicis longus and extensor pollicis brevis; The medial border is formed by the tendon of the extensor pollicis longus; The oor of the impression is formed by the scaphoid and trapezium, and distal ends of the tendons of the extensor carpi

radialis longus and extensor carpi radialis brevis. Structures inside: Remember essentially

The radial artery passes obliquely through the anatomical snuffbox.

Terminal parts of the supercial branch of the radial nerve pass subcutaneously over the snuffbox

Origin of the cephalic vein from the dorsal venous arch of the hand.

Claw Hand

is characterized by:

• Extension at wrist joint-unopposed action of extensors at the wrist• Hyperextension at MP joint• Flexion at IP joints

Claw hand

Struthers’ Ligament

• It is not a constant ligament and can be acquired or congenital.

• Its clinical signicance arises form the fact that the median nerve, passes in the space between the ligament and the

humerus, and in this space the nerve may be compressed leading to supracondylar process syndrome.

• Coracobrachialis is more important morphologically than functionally.It represent the medial compartment of the arm.

• In some animals the muscle is tricipital.I n man the upper two heads have fused,but the musculocutaneous nerve passes

between the remnants of these two heads.

• The third head (and the lowest) head of the muscle has disappeared in man.Occasional persistence of the lower head is

associated with the presence of the so called “ligament of struthers” which is a brous band extending




Ape Thumb Deformity

Injury of median nerve at wrist leads to wasting of thenar muscles and the thumb is adducted and laterally rotated.

Abduction is lost,opposition is lost, exion is lost.

Ape hand defo rmity is a deformity in humans who cannot move the thumb outside of the plane of the palm.

It is caused by inability to oppose the thumb and the limited abduction of the thumb.

Arcade of Frohse

Supinator arch

Is the most superior part o the superficial layer o the supinator muscle, and is a fibrous arch over the posterior interosseous nerve.

Te arcade o Frohse is the most requent site o posterior interosseous nerve entrapment, and is believed to play a role in causingprogressive paralysis o the posterior interosseous nerve, both with and without injury.

Syndromes: (High Yield for 2014)

Pronator syndrome: entrapment o median nerve as it passes between two heads o pronator teres.

Cubital tunnel syndrome: entrapment o ulnar nerv e as it passes between two heads o flexor carpi ulnaris.

Carpal tunnel syndrome: entrapment o median nerve as it passes in carpal tunnel

Cleidocranial Dysostosis

Congenital absence o clavicle.

Patient can approximate both shoulders close to each other in ront o chest.

Faulty ossification o membranous bones.

Additional skull bone deormities are also seen.

Four Rotator Cuff Muscles are

Supraspinatus, UP 2006

Infraspinatus, UP 2006

eres minor,

Subscapularis

Functions

Infraspinatus and teres minor are lateral rotators of the shoulder joint.

Resists shearing forces of the deltoid muscle during abduction and forward exion.

Stabilizes humeral head during the movement of the shoulder joint

Subscapularis is a medial rotator

Supraspinatus initiates abduction.




Frozen shoulder is adhesive capsulitis or periarthritis

Dropped shoulder paralysis of trapezius UP 2006

Chronic supraspinatus tendinitis is painful arc syndrome.

Tennis elbow is lateral epicondylitis.

Golfers elbow is medial epicondylitis.

Base pitchers elbow is damage to soft tissues/ bones around elbow.

De quevarians disease is tenosynovitis of Extensor pollicis brevis and abductor pollicis

longus.

Trigger nger is thickening of tendon sheaths at metacarpophalyngeal joint.

Mallet nger is avulsion of extensor tendon of distal interphalengeal joint.

Remember

FROZEN SHOULDER (ADHESIVE CAPSULITIS OR PERIARTHRITIS)It is due to tendinitis involving rotator cuff. All shoulder movements are restricted due to adhesions.Its cause is unknown.

Spontaneous recovery is seen in six to twelve months.

Subluxation of Radial head/Pulled Elbow

This is common in young children. The annular ligament is funnel shaped in adults while it is tubular/vertical in children.

When child is suddenly lifted or pulled up by forearm (when forearm is pronated) in following circumstances:

To remove child from danger

To pull child upstairs

When child indulges in temper tantrum

Trigger Finger: (High Yield for 2014)

“It is due to localized inflammation o a tendon and its enveloping synovial sheath (tenosynovitis) o the superficial and deep flexortendons over the metacarpal head.”

Tere is thickening and narrowing o the sheath, and a nodular enlargement develops in the tendons distal to the pulley. Tese changesinterere with the smooth gliding o the tendons through the fibrous sheath.

MALLET FINGER

Tis is caused by hyperflexion that disrupts the extensor mechanism o the distal phalanx. It is common in baseball players.

Tree types o injury occur:

Stretching o the extensor tendon

Complete disruption o the extensor tendon Avulsion racture o the base o the distal phalanx

Mallet Finger




VOLKMANN’S ISCHAEMIC CONTRACTURE

Flexion deormity o wrist and fingers resulting rom fixed contracture (shortening) o flexor muscles o orearm.

CausesTe ischaemia o flexor muscles because o

Injury to brachial artery/spasm/obstruction o artery near elbow

Supracondylar racture with displacement

ight plaster cast/bandage

Klippel Feil syndrome: Tere is bilateral ailure o descent o scapula. Other associated anomalies are ailure o usion o occipital bone anddeect in cervical spine. Tis results in webbing o neck and gross limitation o movements o neck.

Dupuytrens Contracture

It is a progressive thickening and shortening o the palmar aponeurosis which results in flexion deormities o the fingers and distalpalm.

Dupuytrens contracture mainly affects middle-aged men.

It most commonly affects the ring and little fingers, ollowed by middle finger.

Tenosynovitis

It is an inflammation o a tendon and its surrounding synovial sheath. Purulent tenosynovitis is a serious inection because it producesadhesions within the tenosynovial canal. When treatment is delayed, the inection passes to a sub-acute state that produces progressivedestruction. Te inection is usually secondary to a puncture wound. Te onset is insidious.

Signs of Tendon Sheath Infection

Uniorm swelling

Fixed flexion where the finger is held in slight flexion

Pain on attempted passive extension o the partly flexed finger

enderness along the course o the tendon sheath into the distal palm.

GANGLION

The most common site is the dorsum of the wrist just lateral to the common extensor of the ngers.

It is considered that a ganglion results from cystic degeneration of connective tissue near joints or tendon sheaths.

The only nding may be a slowly growing, localized swelling. Most patients report intermittent aching & mild weakness.

Painfu l Arc Syndrome (SUPRASPINATUS SYNDROME) (High Yield for 2014)

It is characterized by

• Pain in 60-120 degree abduction

• Chronic thickening of supraspinatus tendon causing impingement of tendon against coraco-acromial arch.

Causes of the synd rome

• Violent dislocation of the shoulder

• Tear of supraspinatus tendon

• Calcied deposit in supraspinatus tendon

• Injury of greater tubercle




The Carpal Bones

Te 8 carpal bones are arranged in 2 rows.

Te proximal row, which contains the scaphoid, lunate, triquetrum, and pisiform, articulates with the radius and triangularcartilage to form the carpus.

Te distal row contains the trapezium, trapezoid, capitate, and hamate.

Te ulnar nerve runs deep to the exor carpus ulnaris tendon through the canal o Guyon.

Te median nerve lies between the exor carpus radialis and the palmaris longus tendon in the carpal tunnel. Blood is

supplied via the radial and ulnar arteries, which form the dorsal palmar arch.

Te scaphoid bone receives its blood supply from the distal part of this arch, which is prone to injury. (especially AvascularNecrosis). The scaphoid is usually fractured secondary to hyperextension of the wrist, often from falls onto the outstretched

hand.

Carpal bone dislocation is usually the result of extreme exion or extension injuries of the wrist. The type of dislocation

or fracture-dislocation produced by these mechanisms depends on the direction and intensity of the acting force or theposition of the hand in relation to the forearm at the moment of impact. The integrity of the lunate-capitate relationship

is the most crucial factor in all dislocations of the wrist. Lunate is the bone most commonly to undergo dislocation and

dislocation o lunate can cause median nerve injury.

CARPAL TUNNEL SYNDROME

Most common entrapment mononeuropathy

Compression o median nerve as it passes through fibro-osseous tunnel beneath flexor retinaculum. Structures in carpal tunnel:

endon o FDP (Flexor digitorum proundus)

endon o FPL (Flexor pollicis longus)

endon o FDS (Flexor digitorum superfici alis)

Median nerve

Tunnel may be Narrowed by

Ar thri ti c changes in wris t joint (rheumatoid arthr it is )

Anter io r dis locat ion of lunate/compl ication of co lles f racture

Soft tissue thi ckening i n myxoedema and acromegaly.

Oedema and obesity i ncluding pregnancy.

Scaphoid Fracture

Fracture scaphoid




Fall on Out stretched hand

Most ractures o the scaphoid waist result rom a all on the outstretched hand, which produces a break through the waist o the scaphoid.

Signs and Symptoms

Tenderness and pain over t he anatomical snuffbox

Swelling and loss of the normal concavity of the dorsoradial region of the wrist

Discomfort during thumb movements

ROTATOR CUFF TEARS

The rotator is composed of the tendons of the

• supraspinatus,

• infraspinatus,

• subscapularis &

• teres minor.

These are attached to the anterior, superior & posterior aspect of upper end of humerus.

Al len's Test: (High Yield for 2014)

“is test o sufficiency o the blood supply to the hand by compression and release o the ulnar and radial arteries” and observation othe colour change o the hand. In hand operations An Allen test should be perormed beore operation to ensure adequate collateral flowrom the ulnar artery so that the problem o hand ischemia is minimized.

Te examination o patients with carpal injuries includes careul palpation to detect areas o tenderness, edema, or contusion;measurements o range o motion; motor and sensory assessment; and use o the Allen test to “determine the integrity o the radialand ulnar arteries.”

LOWER LIMB

“ Holdens Line” and its Importance

Te deep layer o superficial ascia is firmly attached to the deep ascia o thigh along a horizontal line a little lateral to pubic tubercle andextends or about 8 cm. laterally; “Tis line o Firm Attachment” is called Holdens Line.

Clinical importance: “Te Extravasation o urine between these two layers cannot extend into the Tigh” because o the firm attachment.

Patellar Plexus

It is a “Plexus o Nerves in ront o Patella” and upper end o ibia. It is ormed by Anterior division o Lateral and Medial cutaneous nerve




Intermediate Cutaneous nerve and Inrapatellar branch o Saphenous nerve

Housemaids Knee

Chronic enlargement o “Prepatellar bursa” is known as Housemaids knee because it commonly occurs in housemaids who have to kneelregularly or sweeping the floor.

Miner’s Beat Knee

It is “Acute suppurative prepatellar bursitis in miners.”

Clergyman’s Knee

It is enlargement o “Subcutaneous inrapatellar bursa in clergyman.”

Iliotibial Tract

Te “Tickening o Fascia lata on the lateral side o the thigh is called the illiotibial tract.”

Functions

Iliotibial tract stabilizes knee both in extension and partial flexion, i.e, during walking and running.

In leaning orwards with slightly flexed knees, it is the only antigravity orce to support the knee.

Muscles of the Front of Thigh

Te articularis genu pulls the synovial membrane upwards during extension o knee.

Te iliacus and psoas are the muscles o the iliac region and also the part o posterior abdominal wall. Tey are the chie and powerulflexors o the hip. Tey are supplied by spinal segments rom L2, 3.

Muscle Action Nerve Supply

Sartorius Adductor and lateral rotator of thigh andexor of leg

Femoral nerve (L2, 3, 4)

Quadriceps femoris Extensor of the leg Femoral nerve

Rectus femoris Flexes the hip

Vastus lateralis

Vastus medialis Prevents lateral displacement of the patella

Vastus intermedius

Gluteal Region

Muscle Action Nerve supply

• Gluteus maximus • Chief extensor of the thigh at the hip • Inferior gluteal

• Gluteus medius • Abductor of thigh • Superior gluteal

• Gluteus minimus • Abductor of thigh • Superior gluteal

• Piriformis • Lateral rotators of thigh • Ventral ramus of S1,2.

• Gamellus superior • Lateral rotators of thigh • Nerve to obturator internus

• Gamellus inferior • Lateral rotators of thigh • Nerve to quadratus femoris

• Obturator internus • Lateral rotators of thigh • Nerve to obturator internus

• Quadratus femoris • Lateral rotators of thigh • Nerve to quadratus femoris

• Obturator externus • Lateral rotators of thigh • Posterior division of obturator nerve

• Tensor fascia lata • Abductor and medial rotator of thigh • Superior gluteal




Muscles of Back of Thigh


Semitendinosus Chief exors of knee Tibial part of sciatic nerve

Semimembranosus Chief exors of knee Tibial part of sciatic nerve

Biceps femoris Chief exors of knee Long head from Tibial part of sciatic nerve and short head from

common peroneal part of sciatic nerve

Adductor Compartment of Thigh


Adductor longus Adductors of thigh Flexion & lateral

rotation of thigh

Obturator nerve

Adductor brevis Adductors of thigh Flexion & lateral

rotation of thigh

Obturator nerve

Adductor magnus Extends the thigh Obturator nerve & tibial part of sciatic nerve

Gracilis Flexor and medial rotator of thigh Obturator nerve

Pectineus Femoral nerve & obturator nerve

FEMORAL TRIANGLE

The Contents of Femoral Triangle are

Femoral artery

Branches o emoral artery:

deep branches: prounda emoris, deep external pudendal and muscular

Superficial branches: superficial external pudendal, superficial epigastric and superficial circumflex iliac.

Femoral vein (medial to artery) and its tributaries.

Femoral sheath

Femoral nerve

Nerve to pectineus

Femoral branch o genitoemoral nerve

Lateral cutaneous nerve o thigh and

Deep inguinal lymph nodes.

Femoral Sheath

It is a unnel shaped ascial sleeve enclosing the upper 1 ½ inches o the emoral vessels.

It is ormed by the downward extension o the abdominal asciae.

Te anterior wall is ormed by ascia transversalis and posterior wall by ascia iliaca.

Femoral Canal

It is the “Medial compartment o the emoral sheath.” It is conical and ½ inch wide at base and ½ inch long.

Femoral Ring:

Te “Base or Upper end o the Femoral Canal is called the Femoral Ring”. Te emoral ring is filled by condensed extra peritonealtissue, the emoral septum, containing a lymph node and covered by parietal peritoneum.




Te boundaries o the Femoral ring are

Anterior: inguinal ligament

Posterior: pectineus and its ascia

Lateral: septum separating it rom the emoral vein.

Medial: concave margin o lacunar ligament.

Te contents o emoral canal : L3

Lymph node (o Cloquet or o Rosenmuller)

Lymphatics

Loose Areolar tissue

Femoral hernia

Adductor Canal

The boundaries of the Adductor Canal

Posteriorly:

Adductor longus above and

Adductor magnus below

Anteriorly: vastus medialis

Medially: Sartorius which lies on a ascial sheet extending across the anterior and posterior walls.

Te extent o the Adductor Canal: It extends rom the apex o the emoral triangle to the tendinous opening in the adductor magnus.

The Contents of the Adductor Canal are

Femoral artery

Femoral vein

Descending genicular branch o the emoral artery

Saphenous nerve

Nerve to vastus medialis

Obturator nerve




POPLITEAL FOSSA: (HIGH YIELD FOR 2014)

The Boundaries of the Popliteal Fossa

Superolaterally: biceps emoris tendon

Superomedially: semimembranosus and semitendinosus

Ineromedially: medial head o gastrocnemius

Inerolaterally: lateral head o gastrocnemius and plantaris.

Structures form the Floor of the Popliteal Fossa

From above downwards:

Te popliteal surace o the emur

Te capsule o the knee joint

Popliteal ascia

NERVES OF LOWER LIMB

Femoral nerve (posterior divisi on o f L2,L3,L4) An ter ior compartment of high

Obturator nerve(anterior d ivision o f L2,L3,L4) Medial compartment of thigh AIIMS 2000

Tibial nerve Posterior compartment of thigh

Posterior compartment o leg

Common peroneal nerve Short head of biceps femoris

Supercial peroneal nerve Lateral compartment of leg

Injury causes loss of eversion of foot.

Deep peroneal nerve Anter ior compar tment of leg

Injury causes foot drop.

• Superior gluteal nerve(Very important) Gluteus minimus, gluteus medius, tensor ascia lata NO Gluteus

maximus. AIIMS 2010

injury Causes

loss of abduction of limb

Impairment of gait

Patient cannot keep pelvis level when standing on one leg.

Tredlenburgs sign +

• Inferior gluteal nerve Gluteus maximus. Injury causes:

Weakened hip exion

Difculty rising from sitting position.

Trendelenburg Test

Normally when a person is made to stand on one leg, the hip abductors o the ipsilateral side raise the opposite and the unsupported side othe pelvis, I the abductor mechanism is deective, the unsupported side o the pelvis drops and this is known as positive rendelenburg test.Failure o any o the component o the abductor mechanism may result in positive rendelenburg test.

A positive rendelenburg is relatively non-specific and may indicate:

Pain (e.g. due to osteoarthritis o the hip joint)

Weak hip abductors (gluteus medius, gluteus minimus)

Short emoral neck

Fracture o neck




Dislocation or subluxation o the hip.

Neuropathy

Gluteus medius and minimus are supplied by Superior Gluteal nerve.

Compartment Syndromes of Lower Limb

Deep posterior compartment syndrome: there will be pain on passive dorsiexion of the foot and on toeextension (since

muscles in the deep post compartment are plantar exors and phalangeal exors)

Anterior compartment syndrome: there will be pain on passive plantar exion of the foot and toe exion.

Lateral compartment syndrome: there will be pain on passive foot inversion.

Superficial posterior compartment syndrome: pain is on passive dorsiexion of foot.

Denitive diagnosis of a chronic CS can be made with an Intracompartmental pressure test. A catheter is inserted into the

offending compartment to measure its pressure.

Action of Various Muscles of Lower Limb

Hip Joint

Medial rotator of thigh:

Gracilis

Lateral rotators of femur are:

Obturator internus, Obturator externus,

Sartorius, Pyriformis, TN 2008

Superior gamelus, inerior gamellus DNB 2001

Abductors o the hip include the gluteus medius and gluteus maximus. AI 2000

Adductors o the hip include the adductors longus, brevis, and magnus.

Extensors and lateral rotator o the hip include gluteus maximus.

Iliopsoas is flexor o hip

Remember

ensor ascia lata is extensor o knee, Abductor and medial rotator o hip. (Imp )

Ilio tibial tract is flexor, external rotator, abductor o hip. (imp)

Knee joint

Extensor of knee: quadriceps femoris. DNB 2001

Flexion of knee: biceps femoris. Semimembranosus, semitendonosus

Medial r otation: Semimembranosus, semitendonosus, popliteus

Lateral ro tation: biceps femoris

Gems about Gastrocnemius

Is a strong plantar flexor o oot.

Fabella is a sesamoid bone developing in Lateral Head o Gastrocnemius.

Muscles used in normal walk during stance and swing: Gastrocnemiu DNB 2004

Long plantar ligament is divorced tendon o gastrocnemius.

An important Bursa (Brodies Bursa lies deep to Medial head o gastrocnemius)

endon o Gastrcnemius uses with tendon o soleus to orm endo Achillis.

Sural nerve passes between two heads o gastrocnemius.

wo heads o gastrocnemius along with soleus are called riceps surae




Gems About Popliteus (High Yield for 2014)

Popliteus is a flat muscle that orms the floor o the lower part o the popliteal ossa. It arises within the capsule o the knee joint by astrong tendon, which is attached to a depression at the anterior end o the groove on the lateral aspect o the lateral condyle o the emur

Popliteus is attached to the medial aspect o the fibular head by the popliteofibular ligament, which passes laterally and ineriorly romthe popliteus tendon. Tis ligament is the single most important stabilizer o the posterolateral region o the knee and resists external

rotation o the tibia on the emur. Popliteus rotates the tibia medially on the emur or, when the tibia is fixed, rotates the emur laterally on the tibia. It is usually regarded

as the muscle that 'unlocks' the joint at the beginning o flexion o the ully extended knee.

PSOAS ABSCESS

uberculous disease o body o any o the thoracic or lumbar vertebrae gives rise to a cold abscess ( no signs o inflammation). Tis abscesstrickles under psoas sheath up to the insertion o psoas major. Tis painless swelling may be mistaken or a emoral hernia & flexion deormityo hip it due to spasm o psoas.

IMPORTANT POINTS

Meralgia Parasthetica Lateral cutaneous nerve of Thigh

An ter ior Tarsal Tunnel Syndrome: Deep peroneal nerve

Tarsal Tunnel syndrome: Tibial nerve

Joggers Foot: Medial plantar nerve

Hip Pointer: Iliac Crest

Tennis Leg: Gastrocnemius Soleus strain

ILIOTIBAL TRACT FRICTION SYNDROME

It is caused by the tense iliotibal tract rubbing the lateral femoral condyle during running. It induces an inammatory

response. The resulting lateral knee pain is felt above the joint.

Iliotibal tract friction syndrome usually occurs in:

Bowlegged runners (joggers) with pronated feet

Wearing shoes with worn lateral soles

Important Facts about Joints of Lower Limb

Hip

Ileo emoral ligament is ligament o Bigelow.

It is the strongest ligament.

It prevents hyperextension o hip. AI 1997

Pain o hip is reerred to knee joint.






Flexor digitorum longus

Flexor hallucis longus and

ibialis posterior

TendocalcaneousIt is a long tendon, receiving the insertion o fibres o soleus

The Muscles Found in Different Layers of Sole of Foot

From without Inwards

First layer:

Flexor digitorum brevis

Abductor hallucis

Abductor digiti minimi

Second layer:

Flexor digitorum accessories

Lumbricals: our in number

Tird layer:

Flexor hallucis brevis

Flexor digiti minimi brevis

Adductor hallucis

Fourth layer:

Tree plantar and our dorsal interossei.

Plantar Aponeurosis and its Functions

It is the Tickened Cental Part o the Deep Fascia o Sole.

Functions

Gives origin to muscles o first layer o sole

Helps in maintaining the longitudinal arch o the oot

Protects the digital vessels and nerves and deeper muscles

Provides attachment to skin o sole

The Functions of Interossei of Sole

Dorsal interossei: abductors o the toes

Plantar interossei: adductors o the toes

Nerves Related to Lower Limb Compartments (Revise)

Adductor compartment o f thigh : AIIMS 2000 obturator nerve

Flexor compartment of thigh: femoral nerve

Posterior compartment of thigh (hamstrings): tibial part of sciatic nerve

Gluteal region: superior and inferior gluteal nerves

Anter io r compar tment of leg : deep peroneal nerve

Lateral compartment of leg: supercial peroneal nerve

Posterior compartment of leg: tibial nerve

Q angle: quadriceps angle is ormed by line o pull o quadriceps emoris muscle and that o ligamentum patellae as they intersect atcentre o patella. more pronunced in emales




Genu valgum (knock knee) angle < 165°

Genu varum (bow legs) angle > 180°

The Common Peroneal Nerve

Branches into the superficial and deep peroneal nerves, which supply the muscles o the anterior compartment o the leg and cutaneous areaso the distal anterior leg, dorsum o the oot, and most o the digit

The Tibial Nerve

Supplies all the muscles in the posterior compartment o the leg (e.g, tibialis posterior, flexor digitorum longus, gastrocnemius and soleus).

Movements at Different Join ts:

• Ankle: Dorsiexion, Plantar exion

• Subtalar joint: Inversion, eversion UP 2008

• Mid tarsal joint: Forefoot adduction and abduction

Movements at Hip Joint and Muscles Producing these Movements

Flexion • Psoas major, iliacus, Sartorius

Extension • Gluteus maximus, hamstrings

Adduct ion • Adductor longus, brevis, magnus

Abduct ion • Gluteus medius, minimus, tensor facia lata

Medial ro tation • Tensor facia lata

Lateral rotation • Two obturators, two gamelli and quadrates femoris

Arter ial Supply of Hip Joint

Obtuator artery

Medial circumflex artery

Lateral circumflex artery

Superior gluteal artery

Inerior gluteal artery

Subcapital fracture causes Avascular necrosis of head of femur

Nerve Supply of Hip Joint

Femoral nerve through nerve to rectus emoris. Anterior division o obturator nerve Nerve to quadrates emoris Superior gluteal nerve




Movements at Knee Join t and Muscles Producing these Movements

• Flexion • Biceps femoris, semimembranosus, semitendonosus

• Extension • Quadriceps femoris

• Medial ro tation • Popliteus, semimembranosus, semitendonosus

• Lateral rotation • Biceps femoris

Arter ial Supply of Knee Joint

Genicular branches of popliteal artery Genicular branches of femoral artery Genicular branches of lateral circumex femoral artery

Branches of anterior tibial artery

Branches of posterior tibial artery

Nerve Supply of Knee Joint

Femoral nerve through nerve to vasti Posterior division o obturator nerve Sciatic nerve through tibial and common peroneal nerves

Largest & most complex joint of the body = knee joint Locking of the knee joint is brought about by = Quadriceps Unlocking of the knee joint is done by = Popliteus Meniscus which is more vulnerable to injury = medial meniscus because of its xity to the tibial collateral ligament & greater

extension during rotatory movements.

Remember

Bursitis of Knee Joint

Housemaid’s knee is the result o inflammation o Prepatellar bursa MP 2009

Miners beat knee is the result o inflammation o Prepatellar bursa Clergymans knee is the result o inflammation o subcutaneous inra patellar bursa.

Ankle Joint




Dorsiexion • Tibialis anterior

• Extensor digitorum longus

• Extensor hallucis longus

• Peroneus tertius Plantar exion • Gastrocneimus

• Soleus

• Plantaris

• Tibialis posterior

• Flexor hallucis longus

• Flexor digitorum longus

Inversion • Tibialis posterior

• Flexor hallucis longus

• Flexor digitorum longus

Eversion • Peroneius longus

• Peroneus brevis

• Peroneus tertius

Te Flexor Retinaculum is a broad band o deep ascia on the medial side o ankle.

Structures passing deep to flexor retiniculum are:

ibialis posterior

endon o FDL (Flexor Digitorum Longus)

endon o FHL (Flexor Hallicus Longus)

Posterior ibial artery

ibial Nerve

Te Extensor Retinaculum is a Y shaped broad band o deep ascia in ront o ankle.

Structures passing deep to Extensor retiniculum are:

ibialis anterior

endon o EDL (Extensor Digitorum Longus)

endon o EHL (E xtensor Hallicus Longus)

Anterior ibial artery

Deep Peroneal Nerve

Peroneus ertius

The Perforators in Lower Limb (High Yield for 2014)

Tere are the veins connecting the superficial veins with the deep veins and they permit only unidirectional flow o blood, rom superficial tothe deep veins by means o valves.

Calf Pump or Peripheral Heart (High Yield for 2014)

In upright position, venous return rom lower limb depends largely on the contraction o cal muscles, these are known as cal pump. Tesoleus is called peripheral heart or same reason.




Varicose Veins

I the valves in veins become incompetent, the pressure during muscular contraction is transmitted rom deep veins to the superficial veins(leakage o blood).this causes dilatation o the superficial veins, known as varicose veins. Later on gradual degeneration occurs, leading to

varicose ulcers.

Meralgia Paraesthetica

It is a clinical condition characterized by pain, tinging, numbness or anaesthesia in the area o distribution o the lateral cutaneous nerve othe thigh. Tis nerve (a branch o the lumbar plexus) usually enters the thigh by passing deep to the inguinal ligament. Occasionally, the nervepierces the ligament and may then be compressed by it with resultant irritation o the nerve.

The Adductor Spasm

It is spasm o the adductor muscles o the thigh and occurs in spastic paraplegia.

Sciatica

Sciatica is the term applied when pain is elt along the course and distribution o the sciatic nerve, i.e, in the buttock, posterior aspect o the

thigh and leg, and lateral aspect o the leg and oot. Tis is due to irritation o one or more o the roots o the sciatic nerve, and commonlyoccurs due to a prolapsed intervertebral disc in the lumbar region.

Trendelenburg Test (High Yield for 2014)

Tis test is employed for testing the stability of the hip joint. A positive test indicates a defect in osseomuscular stability expecially abductors of hip joint and the patient has a lurching gait. If the patient is asked to stand on one leg. If the abductors of thigh are paralysed on that side, they will beunable to sustain the pelvis against

LIGAMENTS AT ANKLE JOINT

DELOID LIGAMEN (medial collateral ligament)

Consists o superficial and deep fibres.

Supercial Fibres

Anterior tibionavicular

Middle tibiocalcaneal

Posterior tibiotalar

Deep Fibres

Anterior tibiotalar

Lateral Collateral Ligament

• Anterior talobular

• Posterior talobular

• Calcaneobular

THE ARCHES OF FOOT (HIGH YIELD FOR 2014)

Te “medial” longitudinal arch is ormed by calcaneum, talus, navicular, three cuneiorms and three medial metatarsals. Te “lateral” longitudinal arch is ormed by calcaneum, cuboid and lateral two metatarsals. Te “transverse” arch is ormed by the bases o the five metatarsals and the adjacent cuboid and cuneiorms o both eet. Pes “Planus” (flat oot): Due to flattening o the longitudinal arch, in particular the medial arch




Pes “Cavus” (high arched oot): Te congenital orm is probably due to shortness o the plantar ascia (aponeurosis). Te acquired ormcan be due to paralysis o the intrinsic muscles o the oot due to a lesion o the tibial nerve.

The Talipes Deformity of the Foot

In talipes the oot does not lie in Plantigrade position. Te person walks either on the heels or on the toes.

When he walks on the heel the condition is known as alipes Calcaneus while walking on the toes is known as alipes Equines. In boththese conditions the oot may be inverted (varus) or everted (valgus).

Hallus Valgus

In hallux valgus, there is “Lateral Deviation o the Great toe at the Metatarsophalangeal joint.”

Hallux Valgus

Ganglion

It is a cystic lesion ound in close association with a joint capsule or tendon sheath.

Te most common site is the dorsum o the wrist just lateral to the common extensor tendons o the fingers.

WEAVERS BOTTOM

A bursa between gluteus maximus and ischial tuberosity gets inflammed in individuals who work in a sitting position with constantmovements o lower limbs. Te local riction accounts or bursitis. Tis is commonly seen in weavers.

CALCAR FEMORALE: (HIGH YIELD FOR 2014)

Te internal structure o upper end o emur is characterized by presence o trabeculae-thin sheets o compact bone. Inerior cortex o base

o neck o emur. Te trabeculae join to orm plates termed lamellae. Te arrangement and nature o these bony plates is to strengthen thebone and offer resistance to the tensile or shearing orce. Tus extending rom the linea aspera in to the neck is a well defined vertical plateo bone called calcar emorale. It merges medially with the posterior wall o the neck and laterally with greater trochanter.

Perthes Disease

It is also known Coxa Plana o Legg-Calve-Perthes disease.

Here there is Osteochondrosis o the Head o the emur in children which is characterized by initial epiphyseal necrosis ordegeneration followed by regeneration or recalcication. Flattening of head thickening of neck of femur.




CoxaVera

In adult males the neck shaf angle o emur is about 135°. In emales, it is less. With age the angle gradually diminishes in both sexes. Intrauma or local or general disease o the bone, there is reduction o this angle. Tis reduction o neck shaf angle is termed as Coxa Vera.

COXA VALGA: (HIGH YIELD FOR 2014)

It is a rare deormity. It is the reverse deormity causing increase in neck shaf angle o emur. Here the limb is abducted and externallyrotated. It occurs in old cases o inantile paralysis. Even in below knee amputee, the weight o the dragging limb causes this deormity.

Popliteal Ar tery Aneurysm

A localized dilatation o the popliteal artery is termed as aneurysm. Due to decline in the definitive causative reasons (syphilis) nowaneurysm o popliteal artery are ar less common. For surgical correction o this condition, emoral artery is ligated in the adductor canal.

FOOTBALLER’S ANKLE

Football goalkeeper kicks the ball mostly from close to proximal part of dorsum of foot in a plantar-exed position. Over a period of time, the repeated impact initiates formation of bony spicule on the front of neck of talus.This makes the

ankle painful.

Foot Drop

Te Common Peroneal (lateral popliteal) Nerve commonly injured and the common causes o the injury.

Te nerve is commonly injured where it winds round the neck o the fibula. It may be damaged at this site by the pressure o a tightbandage o plaster cast, in severe adduction injury to the knee or rom direct trauma.

ROOT VALUES OF IMPORTANT NERVES OF UPPER/LOWER LIMB

Ax il lary nerve: C5, C6

Ulnar nerve: C7, C8, T1

Radial nerve: C5, C6,C7, C8, T1

Pudendal nerve: S2,S3, S4 MP 2009

Femoral nerve: L2, L3,L4(DORSAL DIV)

Obturator nerve: L2,L3,L4(VENTRAL DIV) UP 2005

Reexes

Biceps • C5, C6

Supinator • C5, C6

Pronator • C5, C 6

Triceps • C6, C7

Cremaster • L1, L2

Knee • L2, L3, L4

Plantar • L5 S1

Ankle • S1, S2

Anal, Bulbocavernous • S3 S4




The Important Points about Viscera

Breast

Te protuberant part o the human breast is generally described as overlying the 2nd to the 6th ribs, and extending rom the lateral

border o the sternum to the anterior axillary line. Actually, a thin layer o mammary tissue extends considerably arther rom theclavicle above to the 7th or 8th ribs below, and rom the midline to the edge o latissimus dorsi posteriorly.

Te Axillary tail o Spencein the breast is o considerable surgical importance. In some normal cases it is palpable, and in a ew it canbe seen premenstrually or during lactation. A well-developed axillary tail is sometimes mistaken or a mass o enlarged lymph nodes ora lipoma.

Te lobule is the basic structural unit o the mammary gland. Te number and size o the lobules vary enormously: they are mostnumerous in young women. From 10 to over 100 lobules empty via ductules into a lactierous duct o which there are rom 15 to 20. Each lactierous duct is lined by a spiral arrangement o contractile myoepithelial cells and is provided with a terminal ampulla — areservoir or milk or abnormal discharges.

High Yield for 2014

Te ligaments o Cooperare hollow conical projections o fibrous tissue filled with breast tissue, the apices o the cones being attached

firmly to the superficial ascia and thereby to the skin overlying the breast. Tese ligaments account or the dimpling o the skin overlyinga carcinoma.

Te areola contains involuntary muscle arranged in concentric rings as well as radially in the subcutaneous tissue. Te areolar epitheliumcontains numerous sweat glands and sebaceous glands, the latter o which enlarge during pregnancy and serve to lubricate the nippleduring lactation (Montgomery’s tubercles).

Te nipple is covered by thick skin with corrugations. Near its apex lie the orifices o the lactierous ducts. Te nipple contains smoothmuscle fibres arranged concentrically and longitudinally; thus is an erectile structure which points outwards. Lymphatics o the breastdrain predominantly into the axillary and internal mammary lymph nodes. Te axillary nodes receive approximately 75 per cent o thedrainage and are arranged in the ollowing groups:

Blood Supply is via

internal thoracic artery PGI 2007

Intercostal artery PGI 2007

Lateral thoracic artery.

Lymph Nodes of Breast

• lateral, along the axillary vein;

• anterior, along the lateral thoracic vessels;

• posterior, along the subscapular vessels;

• central embedded in fat in the centre of the axilla;

• interpectoral, a few nodes lying between the pectoralis major and minor muscles;

• apical, which lie above the level of the pectoralis minor tendon in continuity with the lateral nodes and receive the efferents of all

the other groups.

The apical nodes are also in continuity with the supraclavicular nodes and drain into the subclavian lymph trunk which enters

the great veins directly or via the thoracic duct or jugular trunk. The sentinal node is that lymph node designated as the rst axillary

node draining the breast.

The internal mammary nodes are fewer in number and lie along the internal mammary vessels deep to the plane of the costal

cartilages.

Mondor’s disease is thrombophlebitis of the supercial veins of the breast and anterior chest wall (although it has also been

encountered in the arm).

Familial breast cancer Recent developments in molecular genetics and the identication of a number of breast cancer

predisposition genes (BRCA1, BRCA2 and PS3). These women have a risk of developing breast cancer two to 10 times above

baseline.




Lymph nodes below Pectoralis Minor Level 1

Lymph nodes behind Pectoralis Minor Level 2

Lymph nodes above Pectoralis Minor Level 3

The principal nodes which drain the breast are: Axillary Group of Lymph nodes.

About 70 -75% of lymph from breast drains into Axillary group of Lymph nodes, 20% into internal

mammary group of Lymph nodes and 5% into posterior intercostal group of lymph nodes.

Among the Axillary Group Chief is the An ter io r group.

Rotters nodes are int erpectoral nodes

Absence of sternal head of pectoralis major: Polands syndrome

Cancer cells may infiltrate the suspensory ligaments. Te breast then becomes fixed. Contraction o the ligaments can cause puckeringo the skin.

Infiltration o lactierous ducts and their consequent fibrosis can cause retraction o the nipple

Because o communications o the superficial lymphatics o the breast across the midline, cancer may spread rom one breast to theother, and to the opposite axillary nodes as well.

Entrance o cancer cells into the blood vessels accounts or metastasis in the distant bones.

OPENINGS OF DIAPHRAGM: (HIGH YIELD FOR 2014)

Vena caval opening:

Thoraxic 8 level

Inferior vena cava,

Rt phrenic nerve

Oesophageal opening:

Thoraxic 10 level

Esophagus,

vagus nerves,

esophageal branch of lt. gastric artery

Aortic opening:

Thoraxic 12 level

Aorta,

Thoraxic duct, JKBOPEE 2012

Azygous vein. PGI 2003

Esophageal opening lies in muscular part o diaphragm

Vena caval lies in central tendon o diaphragm

Aortic opening is not a true opening but an osseo aponeurotic opening. Greater and lesser splanchnic nerves pierces each crus odiaphragm

Lt crus is also pierced by hemi azygous vein.

Sympathetic chain passes behind medial arcuate ligament

Subcostal nerves vessels pass behind lateral arcuate ligament.

Superior epigastric vessels and lymphatics pass through Foramen o Morgagni (Larrys space) PGI 2004

Musculo phrenic vessels pierce the diaphragm

Hernia does not occur through vena caval opening. AI 2002

Bochaldeks hernia occurs through posterolateral part o diaphragm. AI 1996

Morgagni hernia occurs anteriorly on right usually. AI 2007

Remember Accessory phrenic nerve is commonly a branch rom the nerve to subclavius MP 2004




THE PHRENIC NERVE : (HIGH YIELD FOR 2014)

It is a mixed nerve that provides the sole motor supply to the diaphragm. It arises chiefly rom the ventral rami o ourth cervical, butalso receives contributions rom the third and fifh cervical rami.

Within the thorax, the phrenic nerve descends anterior to the pulmonary hilum, between the fibrous pericardium and mediastinalpleura, to the diaphragm, accompanied by the pericardiophrenic vessels.

In its thoracic course, each phrenic nerve supplies sensory branches to the:

mediastinal pleura,

fibrous pericardium and

parietal serous pericardium.

ESOPHAGUS

Length 25 cm PGI 2004

Commences at lower end of cricoid TN 2002

Has squamous epithelium PGI 2004

Toughest layer is muscularis.

No serosa

Sites of Esophageal Constrictions

Distance from incisor Landmark

6 inches Pharyngeoesophageal junction

9 inches Aortic arch crossing

11 inches Left bronchus

15 inches Pierces diaphragm AIIMS 1992

THE TRACHEA

It is a fibromuscular tube

It is 10 to 12 cm. in length and varying rom 13 to 22 mm. in width.

Approximately 20 U-shaped hyaline cartilages support the trachea laterally and ventrally.

Te trachea originates at the level o the cricoid cartilage and descends through the superior aperture o the thorax and the superiormediastinum to its biurcation at the level o the sternal angle (lower border o the ourth thoracic vertebra).

JKBOPEE 2012

Here it divides into the right and lef primary bronchi.

Te trachea is composed o pseudostratified columnar ciliated cells ,goblet cells ,and basal cells. Basal cells are capable o differentiatinginto goblet or ciliated cells. Other cells making up the epithelium include brush cells, serous cells, and Kulchitsky cells.




HEART

Inferior surface of heart is formed by Rt and Lt ventricle. AI 1993

Base of heart is formed by Rt and Lt atrium. JIPMER 1983

Part of heart lying close to esophagus: Lt atrium. TN 1997

Structures Opening into Right Atrium

SVC

IVC

Coronary Sinus

Anterior Cardiac Veins

Vena Cordis Minimi (Tebasian Veins)

Sometmes the right Marginal Vein

Structures Present InMusculi pectinati : atria of heart

Trabeculae carnea: rt. ventricle of heart JKHND 2005

Moderator band/Septomarginal trabeculae: right ventricle

Coronary sinus, SVC, IVC: open in Right atrium. MAH 2003

SA node is located in: Rt. Atrium

Whole of conducting sys tem is mostly suppl ied by rt coronary artery except

Right bundle branch (supplied by left coronary artery)

Holmes heart: single ventricle

Right coronary artery arises rom anterior aortic cusp AI 2002

Lef Coronary arises rom Posterior aortic cusp.

Posterior interventricular artery determines coronary dominance.

In case it arises rom right coronary artery, right dominance AIIMS 2007

In case it arises rom lef coronary, lef dominance.

Rt Coronary artery mostly supplies SA node, AV node, AV bundle. AI 2003

Te SA node is usually supplied by Right coronary artery and Right Vagus MAH 2002

Te AV node is usually supplied by Right coronary artery and Lef vagus.

Sympathetic innervation is by 2-6 DNB 2001

Maximum (90%) o venous drainage o Heart goes to Coronary Sinus

In etal lie lef sided svc drains into coronary sinus AI 2000

Great Cardiac Vein ollows Anterior Interventricular artery.

Middle Cardiac Vein ollows Posterior Interventricular artery. AI 2003

Small Cardiac Vein ollows Rt. Marginal artery.

Coronary Sinus

is the largest venous channel o the heart about 3 cms . It located in left posterior coronary sul cus.

It is a remnant o lef horn o sinus venosus PGI 2011

while the right horn gets incorporated into right atrium.




It opens into the right atrium o the heart through an orfice o coronary sinus and has a valve called the Tebesian valve. It receives :

Great cardiac vein PGI 2011

Middle cardiac vein PGI 2011

Small cardiac vein PGI 2011

Right marginal vein

Oblique vein o lef atrium

Right marginal vein

Thoracic Duct

Also called as Pecquets duc t. (DNB 2006)

Beaded in appearance.

18 inches in length.

Is the largest lymphatic pathway in body.

The duct commences in the abdomen as an elongated lymph sac of the cisterna chili is: Thoracic duct. (UP 2007)

Begins from cisterna chylii at the level of T12 vertebrae

Injury to thoracic duct by trauma leads to chylothorax

AORTA

Is divided into three parts namely ascending aorta, arch o aorta and descending thoracic aorta lying in the middle, superior andposterior mediastina respectively.

Te ascending aorta lies within the pericardium below the level o sternal angle and arises rom lef ventricle opposite third lef sternocostal junction and ends by becoming the arch opposite 2nd right sterno costal junction. It has three dilatations one anterior and twoposterior which are aortic sinuses or dilatations immediately above the aortic valves.It gives origin to two coronary arteries.

ARCH OF THE AORTA

Te aorta is the largest artery in the body. It extends upward rom the lef ventricle o the heart, arches over the heart to the lef. Te firstportion o the aorta is the "ascending aorta," which branches into the "arch o the aorta." Tree major arteries originate rom the aortic arch:

the "brachiocephalic artery," which supplies blood to the brain and head;

the lef common carotid artery and

the lef subclavian artery.

LUNGS

Bronchopulmonary Segment

Vascular segment

Independent

Bronchial artery supplies till respiratory bronchiole. AI 2008

Largest subdivision of lobe.




Peculiarities of Blood Supply of Lung

• Smallest functional unit of lung is lobule UP 2008

• Blood supply of lung tissue proper is by Bronchial arteries.

• Bronchial arteries are branches of descending Thoracic Aorta.

• They supply nutrition to bronchial tree and pulmonary tissue upto respiratory bronchio le.

• Segments dist al to respiratory bronchiole are supplied by branches from Pulmonary vessels.

• On the right side there is only one BA arising indirectly from descending Thoracic Aorta.

• On the Left side there are two BA arising di rectly from descending Thoraxic Aorta.

• Bronchial arteries are responsible for Haemoptysis.

• Pulmonary arteries carry deoxygenated blood.

• Pulmonary veins carry oxygenated blood.

• Sequestered segments are supplied by s ystemic circ ulation UP 2008

AZYGOS LOBE OF LUNG

Azyos means unpaired. Azygos lobe may be seen on the right lung.

It is seen as a result of developmental anomaly related to lung bud and posterior cardinal vein.

The posterior cardinal vein (future azygos vein) gets embedded in the substance of lung which passes as lung bud below

the arch formed by posterior cardinal vein.

The part of lung medial to the vein forms the azygos lobe.

GEMS ABOUT INTRA ABDOMINAL ORGANS

The Spleen (High Yield for 2014)

Is a haemolymphatic organ.

the second largest organ o the reticuloendothelial system.

It is located in the posterior lef upper quadrant o the abdomen (lef hypochondrium) where its relationships to the diaphragm,stomach, pancreas, lef kidney, and splenic flexure o the colon are maintained by suspensory ligaments. Te splenophrenic, splenorenal,and splenocolic ligaments are usually relatively avascular and their transection allows the spleen to be displaced medially and anteriorly.

Te “Gastrosplenic ligament” extends rom the greater curvature o the body and undus o the stomach to the spleen, contains theshort gastric arteries and veins.

Te “Splenorenal” ligament (Lienorenal) and attached to the spleen at the hilum: splenic artery and vein, lymphatic structures, andofen the tail o the pancreas

Te arterial supply to the spleen is derived rom the celiac artery rom both the splenic artery and the short gastric arteries, whichusually arise as branches o the gastroepiploic or the splenic arteries

Te splenic vein is ormed by a coalescence o polar veins in the splenic hilum and courses with the splenic artery along the dorsalsurace o the pancreas to enter the portal system.

Wandering spleen: Occurs with a longer old o peritoneum attached to spleen and because o that has excess mobility.

orsion o spleen: Occurs in wanderiong spleen and as a result o torsion spleen undergoes atrophy.

Te Accessory spleen: Tese are the splenic nodules which have ailed to use to orm a lobulated mass.

Spleenosis: ragments ospleenic tissue afer rupture disseminate .

Polycystic disease o Spleen: May be associated with cysts in spleen and can be associated with Polycystic Kidney disease.

Kehrs sign: Splenic inarction due to obstruction o branches o splenic artery, causes reerred pain in lef shoulder due irritationo undersurace o diaphragm by effused blood.




THE STOMACH

Starts rom gastroesophageal junction to the pylorus.

It is bounded on the lef by the spleen and on the right by the liver

The Blood Supply to the Stomach is Extensive (High Yield for 2014)

Lef gastric artery, which supplies the upper lesser curvature o the stomach rom celiac trunk

Te right gastric artery branches off the hepatic artery, which originates rom the celiac axis; it supplies blood to the distal lessercurvature.

Te lef gastroepiploic artery is a branch off the short gastric vessels; it comes rom the splenic and thereore originally rom the celiacaxis.

Te right gastroepiploic artery branches off the gastroduodenal artery, which comes originally rom the hepatic artery and thereorerom the celiac axis.

Te venous drainage o the stomach empties in a variety o directions, including venous tributaries along the esophagus, veins that flow withthe short gastrics to the splenic vein, and venous drainage that is carried toward the duodenum and toward the portal vein.

Nerve supply is predominantly by the vagus.

An anterior (lef) and posterior (right) vagus nerve courses with the esophagus until the gastroesophageal junction.

Te “criminal” nerve o Grassi is the first branch o the posterior vagal nerve innervating the greater curvature undus. At the junction o theundus and the antrum o the stomach, the vagal nerves branch and innervate the antrum. Tis vagal branch point is called the crow's oot.

Te lesser sac is bounded ventrally by the stomach and is an important location during operation, in that it is a frequent space for fluidcollection and is an important plane for the exposure of gastric anatomy.

DUODENUM

Te duodenum extends rom the pylorus about 20 to 30 cm. and ends at the ligament o reitz, which is where the jejunum begins. Tis ismarked by adhesive bands between the duodenal-jejunal junction and the retroperitoneum on the lef side o the abdomen.

Te duodenum is divided into our anatomic regions:

the first portion, or the cap or bulb;

the second portion, or the descending duodenum;

the third, or transverse, portion; and the

ourth, or ascending, portion

Gems About Duodenum

Te duodenal cap lies just beyond the pylorus. Ninety percent o ulcers occur in the duodenal cap region.

Te gastroduodenal artery lies directly behind the duodenal cap, and penetrating ulcers into the pancreas initially erode through the gastroduodenalartery, accounting for the massive bleeding that occurs with these ulcers.

Te second (descending) portion o the duodenum: Te ampulla o Vater and the minor papilla both enter into the duodenum in thisportion. Te second portion o the duodenum is approximately 10 cm. in length.

Te third and ourth portions o the duodenum (transverse and ascending portions) are mostly retroperitoneal.

Te third portion is attached to the uncinate process and crosses the abdomen and over the aorta.

Compression o the junction o the third and ourth portions o the duodenum by the angle o the SMA and the aorta is called the SMAsyndrome.

Te ourth portion o the duodenum blends into the jejunum at the ligament o reitz, which attaches this junction to the retroperitoneum.Mobilization o the ligament o reitz is necessary in duodenal resections. Te ligament is ofen composed o small strands o striated musclethat eventually extend to the crus o the diaphragm.

“Kerckring's folds” Te mucosal surface of the small intestine contains numerous circular mucosal folds called the plicae circulares (valvulaeconniventes, or valves of Kerckring) o the duodenum begin just beyond the cap and continue throughout the duodenum. Te concentric oldso Kerckring are approximately 1 to 2 mm. thick and 2 to 4 mm. high. Tey are taller and more numerous in the distal duodenum and proximal

jejunum, becoming shorter and ewer distally.




DIFFERENCE BETWEEN SMALL AND LARGE INTESTINE

Small intestine Large intestine

About 6 -7 metres in length About 180 cms in length

Small diameter Larger diameter

Mucosa has villi and crypts Mucosa has crypts but no villi

Paneth cells present Paneth cells absent

Less goblet cells More goblet cells

Brunner’s glands in duodenum present MAH 2005 Both absent

Peyers patches in ileum present (Peyer's patches are lymph nodules aggregated

in the submucosa of the small intestine. These lymphatic nodules are most

abundant in the ileum, but the jejunum also contains them.)

Sacculations absent Sacculations present

Appendices epiploicae absent Appendices epiploicae present

Taenia absent Taenia present

Jejunum Ileum Large intestine

• Villi present/ leaf like • Villi present/ nger like • Villi absent

• Intestinal glands/ crypts present • Intestinal glands/ crypts present • Intestinal glands/ crypts present

• Initial 2/5 of the small intestine • Terminal 3/5 of the small intestine • Constitutes the distal part of gut

after small intestine

• Tenia coli( three longitudinal bands of

smooth muscle) absent

• Tenia coli( three longitudinal bands of

smooth muscle) absent

• Tenia coli( three longitudinal bands

of smooth muscle) present

• Appendices epiploicae (fatty tags)

absent


absent


present

• Larger diameter than ileum • Smaller diameter than jejunum • Sacculations (haustrations ) of the

wall present• Large plica circularis(folds of mucosa

and submucosa) can be palpated

• Small plica circularis • No plica circularis

• Vasa recta are longer and fewer • Vasa recta are shorter and numerous • Variable

• Peyers patches absent • Peyers patches present • No peyers patches

• More thicker, more vascular and red in

the living person than ileum. Appears

almost empty

• Comparatively thinner,less appears

full,less vascular

• Varies from segment to segment

• Windows are present • Windows are absent • variable

• Arterial arcades 1-2 • More arterial arcades • Variable

• Fat less abundunt • Fat more abundant • Variable

APPENDIX

Te dimensions o appendix: Te length o appendix varies rom 2-20 cm, average about 09cm. it is longer in children.

Te different positions o the appendix: Te base o the appendix is fixed but its tip can point in any direction. Depending on itollowing positions o the appendix are described:

Retrocaecal, commonest

Pelvic

Paracolic

Splenic

Promontoric

Mid inguinal




Valve o Gerlach: It is an indistinct semilunar old o mucous membrane guarding the appendicular orifice.

Te Peritoneal relations o Appendix: Appendix is suspended by a small, triangular old o peritoneum called mesoappendix. Teold passes upwards behind ileum and is attached to the lef layer o mesentery.

Te Characteristic eature o blood supply o appendix (High Yield fo r 2014)

Te appendix is supplied only by appendicular artery, a branch o ileo-colic artery. It runs first in the ree edge o appendicular

mesentery and then distally along the wall o appendix. Mcburney’s point: It is the point o maximum tenderness in acute appendicitis. It lies at the junction o medial 2/3 and lateral 1/3

o a line joining umbilicus to anterior superior iliac spine.

Murphy’s traid: Appendicitis first causes pain around umbilicus. Ten ollowed by vomiting and ever. Tis sequence o symptomsis known as murphys triad.

Te gangrene o appendix is common in acute inections: Because appendicular artery supplying the appendix gets thrombosedand it has no collateral circulation.

Psoas est and Obturator est are used or Appendicitis

Appendicular artery in Mesoappendix




CELIAC TRUNK (HIGH YIELD FOR 2014)

LEF GASRIC ARERY→ oesophageal branch, gastric branch

COMMON HEPAIC ARERY→right hepatic , lef hepatic, GASRODUODENAL ARERY→supraduodenal, right gastroepiploic,

superior pancreaticoduodenal artery SPLEENIC ARERY→ short gastric, lef gastroepiploic, pancreatic branches

Meckel's Diverticulum (High Yield fo r 2014)

A Meckel's diverticulum, a true congenital diverticulum.

It is a vestigial remnant o the omphalomesenteric duct (also called the vitelline duct), and is the most requent malormation o thegastrointestinal tract

Meckel's diverticulum is located in the distal ileum, usually within about 60-100 cm o the ileocecal valve.

It is typically 3-5 cm long, runs antimesenterically and has its own blood supply.

It is a remnant o the connection rom the umbilical cord to the small intestine present during embryonic development.

A Memory aid is the Rule of 2's

2% (of the population)

2 feet (from the ileocecal valve)

2 inches (in length)

2% are symptomatic,

2 types of common ectopic tissue (gastric and pancreatic)

most common age at clinical presentation is 2,

males are 2 times as likely to be affected.

Anal canal above Dentate Line Anal Canal Below Dentate Line

Endodermal Ectodermal

Cuboidal epithelium Stratified sauamous

Superior Rectal artery Omerior Rectal artery

Superior Rectal Vein Inerior Rectal Vein

Internal iliac group o Lymph Nodes Superficial inguinal group o lymph nodes

Pain insensitive Pain sensitive

The Liver

Lies in the right upper quadrant o the abdomen.

It is the largest gland in the body, it weighs approximately 1500 gm.

Te gallbladder lies on the dorsal surace o the liver in a transpyloric plane.

A peritoneal membrane (Glisson's capsule) covers the liver .

Te superior surace o the liver conorms to the undersurace o the right diaphragm. Te relations o the inerior surace o the liverare the duodenum, colon, kidney, adrenal gland, esophagus and stomach. Peritoneum invests the entire liver except or a bare area underthe diaphragm on the posterosuperior surace adjacent to the inerior vena cava and hepatic vein.

Ligaments of Liver

Te alciorm ligament, which attaches the liver to the anterior abdominal wall rom the diaphragm to umbilicus and incorporates theligamentum teres hepaticus




Te anterior and posterior right and lef coronary ligaments, which in continuity with the alciorm ligament connect the diaphragmto the liver. Te lateral aspects o the anterior and posterior leaves o the coronary ligaments use to orm the right and lef triangularligaments.

Te gastrohepatic and hepatoduodenal ligaments, which consist o the anterior layer o lesser omentum and are continuous with the

lef triangular ligament. Te hepatoduodenal ligament contains the hepatic arteries, portal vein, and extrahepatic bile ducts. It orms theanterior boundary o the epiploic oramen o Winslow and the communication between the greater and lesser peritoneal cavities.

MAH 2012

Four Lobes of the Liver are Commonly Described

Right

Lef

Quadrate

Caudate.

PORTAL VEIN

Te portal vein provides about three ourths o the liver's blood supply.

Te combination o the superior mesenteric and splenic veins orms the portal vein, behind the neck o the pancreas.

Te portal vein then passes superiorly, posterior to the first part o the duodenum at the level o the second lumbar vertebra.

Portal vein is 1 to 3 cm. in diameter and 5 to 8 cm. in length beore dividing into right and lef branches at the porta hepatis

Te portal vein usually passes behind the bile duct and hepatic artery in the hepatoduodenal ligament.

Te portal trunk divides into lef and right hepatic branches in the portal fissure. Te lef branch o the portal vein is longer .

Te portal vein divides into small veins and venules, which finally enter hepatic sinusoids.

Te portal vein has no valves.

Portocaval Anastmosis (High Yield for 2014)

Numerous tributaries of the portal vein connect out side the liver with the sys temic venous sys tem. Under normal circumst ances

these communications have little physiologic signicance. However, if portal hypertension develops, these rudimentary portosystemic communications develop into large channels with increased collateral ow.

Sites of Portosystemic Anastomoses Include

Te submucosal veins o the proximal stomach and distal esophagus, which can receive blood rom the coronary and short gastric veinsto drain into the azygous veins (high blood flow through this pathway produces gastric varices, esophageal varices, or both);

Umbilical and periumbilical veins, recanalized rom the obliterated umbilical vein in the ligamentum teres hepaticus, and which maycause caput medusae or the loud Cruveilhier-Baumgarten bruit

ributaries o the inerior mesenteric vein, which include the superior hemorrhoidal veins that communicate with the middle and ineriorhemorrhoidal veins o the systemic circulation and may cause large hemorrhoids; and

Other retroperitoneal communications, including connections to the renal and adrenal veins.




Sphincter of Oddi

Te circular smooth muscle fibers in the ampulla o Vater area constitute the sphincter o Oddi, which regulates the ow of bile from

the liver into the duodenum.

Te three principal parts o the sphincter o Oddi are:

Te sphincter o the choledochus (i.e., the circular muscle fibers surrounding the intramural and submucosal bile duct);

Te pancreatic sphincter, which consists o the amuscular septum between the bile and pancreatic ducts;

Ampullary sphincter: Te ampullary sphincter, the most important component o the sphincter o Oddi, includes a layer olongitudinal muscle fibers that help prevent reflux o intestinal contents into the ampulla.

Relaxation o the ampullary sphincter may promote reflux into the pancreatic duct.

GALLBLADDER

The gallbladder, a pear-shaped (pyriform), distensible appendage of the extrahepatic biliary system.

Capacity: 30 to 50 ml. of bile.

Parts: It has a fundus, body, and neck. The duct of gallbladder cystic duct varies in length and usually contains spiral valves of Heister that regulate

bile ow.

Enlargement of the neck of the gallbl adder such as from a stone may form a pouch (Hartmann's pouch).

The triangle bounded by t he cystic duct, common hepatic duct, and inferior border of the liver is the Triangle of

Calot.

The gallbladder receives its blood supply from the cyst ic artery, which ori ginates from the right hepatic artery.

Venous drainage of the gallbladder enters principally into t he portal vein.

The lymphatics drain into cys tic duct nodes near the superior aspect of the cystic duct. (Cystic Lymph node of

Lund).

The Triangle of Calot (High Yield for 2014)

Is a surgical landmark used to identiy important structures during cholecystectomy, is bounded by the cystic duct, thecommon hepatic duct, and the inerior border o the liver.

Te right hepatic and cystic arteries are located within it, and anomalous structures ofen pass through it.

“Moniyhans Hump”: An abnormal bend in the course o the right hepatic artery, throwing it into the configuration o acaterpillar hump, (Moynihan’s hump) invites injury unless it is careully dissected ree

THE PANCREAS (PAN : ALL CREAS: FLESH)

Is a retroperitoneal organ, lying posterior to the stomach and lesser omentum.

It extends rom the duodenal C loop to the hilum o the spleen.

Te gland has a distinctive yellow/tan/pink color and is multilobulated.

Te pancreas is covered by peritoneum anteriorly, and posteriorly it lies in proximity to the inerior vena cava, right renal vein, aorta atthe level o the first lumbar vertebra, superior mesenteric vessels, and splenic vein.

Te gland is divided into our portions:

Te head (which includes the uncinate process),

the neck,

the body and

the tail.




Te head o the gland extends to the right o the neck, lying within the confines o the duodenal C loop; it includes the posteroineriorextension arising rom the ventral primordium, designated the uncinate process. Te uncinate process extends posterior to the superiormesenteric vein, ending at the right margin o the superior mesenteric artery. Te body o the pancreas lies immediately to the lef o theneck; the tail o the pancreas extends to the lef o the body into the splenic hilum.

Te head o the pancreas is intimately associated with the second portion o the duodenum, and these two structures are jointly suppliedby two arterial arcades known as the anterior and posterior pancreaticoduodenal arteries. Tese arteries originate rom the superiorand inerior pancreaticoduodenal vessels as branches o the celiac axis and superior mesenteric artery, respectively. Te distal bodyand tail o the pancreas are supplied by short branches o the splenic and lef gastroepiploic arteries. Within the posterosuperior andposteroinerior aspects o the body o the pancreas lie the superior and inerior pancreatic arteries, respectively.

Veins draining the pancreatic parenchyma eventually terminate in the portal vein, which arises posterior to the neck o the pancreas atthe junction o the splenic and superior mesenteric veins.

Multiple lymph node groups drain the pancreas.

From the head o the gland, nodes in the pancreaticoduodenal groove communicate with subpyloric, portal, mesocolic, mesenteric,and aortocaval nodes.

Lymphatics in the body and tail o the pancreas drain to retroperitoneal nodes in the splenic hilum or to celiac, aortocaval, mesocolic,or mesenteric nodes.

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Platinum Notes - Anatomy ( 2014-15 )