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Upper extremityUpper extremity

Surface anatomySurface anatomy

ClavicleClavicle ManubriumManubrium Jugular notch (suprasternal notch)Jugular notch (suprasternal notch) DeltoidsDeltoids Scapula, Acromion, spine, coracoid process, Scapula, Acromion, spine, coracoid process,

fossa, borders fossa, borders Humerus, tubercle, bodyHumerus, tubercle, body Ulna, head, olecranon process, ulnar nerveUlna, head, olecranon process, ulnar nerve Radius, radial nerve, styloid processRadius, radial nerve, styloid process Carpals, pisiform, scaphoid and trapezium, Carpals, pisiform, scaphoid and trapezium,

anatomical snuff boxanatomical snuff box

Brachial PlexusBrachial Plexus

Brachial plexus formation….Brachial plexus formation….

The brachial plexus starts from the five The brachial plexus starts from the five ventral rami of the ventral rami of the spinal nerves, after they , after they have given off their segmental supply to the have given off their segmental supply to the muscles of the muscles of the neck. These are the five . These are the five rootsroots..

These roots merge to form three These roots merge to form three trunkstrunks: : "superior" or "upper" C5-C6, "middle" C7, and "superior" or "upper" C5-C6, "middle" C7, and "inferior" or "lower" C8-T1."inferior" or "lower" C8-T1.

Each trunk then splits to form an anterior and Each trunk then splits to form an anterior and a posterior a posterior divisiondivision..

Brachial plexus formation….Brachial plexus formation….

The six divisions will regroup to become The six divisions will regroup to become the the cordscords. The cords are named by their . The cords are named by their position in respect to the position in respect to the axillary artery..

The The posterior cord is formed from the is formed from the three posterior divisions of the trunks.three posterior divisions of the trunks.

The The lateral cord is the anterior divisions is the anterior divisions from the upper and middle trunks.from the upper and middle trunks.

The The medial cord is simply a continuation of is simply a continuation of the lower trunk.the lower trunk.

Brachial plexus formation…Brachial plexus formation…

Branches of the brachial plexusBranches of the brachial plexus 3 branches from the 3 branches from the rootsroots Dorsal scapular nerve

arises from arises from C5 root, supplies the root, supplies the rhomboid muscles and and levator scapulae..

Nerve to subclavius Nerve to subclavius arises from arises from C5 and and C6 roots, supplies the roots, supplies the

subclavius muscle Long thoracic nerve Long thoracic nerve arises from arises from C5, , C6 and and C7 roots, supplies roots, supplies

serratus anterior

Brachial plexus formation…Brachial plexus formation…

1 branch from the 1 branch from the trunkstrunks Suprascapular nerve

arises from the superior trunk, supplies arises from the superior trunk, supplies supraspinatus and and infraspinatus muscles muscles

3 branches from the 3 branches from the lateral cordlateral cord Lateral pectoral nerve

supplies supplies pectoralis major and and pectoralis minor( by ( by communicating with the communicating with the medial pectoral nerve) from C5, ) from C5, C6, C7.C6, C7.

Musculocutaneous nerve Musculocutaneous nerve from C5 and C6 it supplies from C5 and C6 it supplies coracobrachialis, , brachialis and and

biceps brachii. It then becomes the . It then becomes the lateral cutaneous nerve of the forearm..

Lateral root of the Lateral root of the median nerve supplies C5, C6 and C7 fibres to the median nerve.supplies C5, C6 and C7 fibres to the median nerve.

Brachial plexus formation…Brachial plexus formation… 5 branches from the 5 branches from the posterior cordposterior cord Upper subscapular nerve

supplies supplies subscapularis (upper part) from C5 and C6 (upper part) from C5 and C6 Thoracodorsal nerve Thoracodorsal nerve

supplies supplies latissimus dorsi with nerve fibres from C6, C7 and with nerve fibres from C6, C7 and C8 Lower subscapular nerve Lower subscapular nerve

supplies the lower part of subscapularis and supplies the lower part of subscapularis and teres major from from C5 and C6.C5 and C6.

Axillary nerve Axillary nerve from C5 and C6, it supplies from C5 and C6, it supplies deltoid and a small area of and a small area of

overlying skin by its anterior branch.overlying skin by its anterior branch. Its posterior branch supplies Its posterior branch supplies teres minor and deltoid muscles and deltoid muscles

then becomes the then becomes the upper lateral cutaneous nerve of the arm Radial nerve Radial nerve

nerve fibres from all 5 roots (C5-nerve fibres from all 5 roots (C5-T1)) largest nerve of the plexuslargest nerve of the plexus supplies supplies triceps brachii, the skin of the posterior arm as the brachii, the skin of the posterior arm as the

posterior cutaneous nerve of the arm, , anconeus, and the , and the extensor muscles of the of the forearm..

Brachial plexus formation…Brachial plexus formation…

5 branches from the 5 branches from the medial cordmedial cord medial pectoral nerve

from C8 and T1, it supplies from C8 and T1, it supplies pectoralis major and and pectoralis minor medial root of the medial root of the median nerve

supplies C8 and T1 fibres to the median nerve.supplies C8 and T1 fibres to the median nerve. medial cutaneous nerve of the arm medial cutaneous nerve of the arm

supplies the front and medial skin of the supplies the front and medial skin of the arm from C8 and T1 from C8 and T1 medial cutaneous nerve of the forearm medial cutaneous nerve of the forearm

supplies medial skin of the forearm from C8 and T1supplies medial skin of the forearm from C8 and T1 ulnar nerve ulnar nerve

C7, C8 and T1 fibresC7, C8 and T1 fibres supplies supplies flexor carpi ulnaris, the medial 2 bellies of , the medial 2 bellies of

flexor digitorum profundus, most of the small muscles of the , most of the small muscles of the hand and the skin of the medial side of the hand and medial and the skin of the medial side of the hand and medial one and a half fingers one and a half fingers

Anesthesia of the Brachial PlexusAnesthesia of the Brachial Plexus

The fact that the nerves of the brachial plexus are The fact that the nerves of the brachial plexus are grouped together acts as a benefit as well. grouped together acts as a benefit as well. Local anesthetics such as such as lidocaine or or bupivacaine can be can be injected in close proximity to these in close proximity to these nerves, , rendering an entire arm insensate and immobile. rendering an entire arm insensate and immobile. The process of injecting local anesthetic for this The process of injecting local anesthetic for this purpose is called purpose is called regional nerve blockade or more or more simply, a nerve block, and it is a common procedure simply, a nerve block, and it is a common procedure in in anesthesia. After an onset time of approximately . After an onset time of approximately 10 to 15 minutes, the targeted arm will be fully 10 to 15 minutes, the targeted arm will be fully anesthetized and ready for anesthetized and ready for surgery. The patient can . The patient can remain awake during the ensuing surgical remain awake during the ensuing surgical procedure, or he can be sedated with medications procedure, or he can be sedated with medications or fully anesthetized with or fully anesthetized with general anesthesia

Peripheral nerve Peripheral nerve blockadeblockade The use of peripheral nerve blockade (in this case, a "brachial plexus The use of peripheral nerve blockade (in this case, a "brachial plexus

nerve block") offers several advantages when compared to general nerve block") offers several advantages when compared to general anesthesia or local anesthesia:anesthesia or local anesthesia:

The patient can remain awake and breathing on their own, thus The patient can remain awake and breathing on their own, thus protecting themselves from aspiration of stomach contents into the protecting themselves from aspiration of stomach contents into the lungs. By avoiding general anesthesia, patients with adverse reactions lungs. By avoiding general anesthesia, patients with adverse reactions to general anesthetics (to general anesthetics (viz.viz. malignant hyperthermia, severe post- malignant hyperthermia, severe post-operative nausea and vomiting, known hypersensitivity to agents) can operative nausea and vomiting, known hypersensitivity to agents) can be successfully treated. Similarly, patients who experience nuisance side be successfully treated. Similarly, patients who experience nuisance side effects from general anesthesia such as nausea, vomiting, or excessive effects from general anesthesia such as nausea, vomiting, or excessive sleepiness can minimize these symptoms.sleepiness can minimize these symptoms.

There is no need to perform an There is no need to perform an endotracheal intubation, the procedure , the procedure of inserting a breathing tube into the trachea. Occasionally, such of inserting a breathing tube into the trachea. Occasionally, such intubation is unexpectedly difficult to perform, causing injury to the intubation is unexpectedly difficult to perform, causing injury to the patient.patient.

The affected limb's The affected limb's sympathetic nerves are anesthetized, leading to are anesthetized, leading to vasodilation. This improves . This improves blood flow to the affected limb and makes to the affected limb and makes microvascular surgical procedures technically simpler.microvascular surgical procedures technically simpler.

The limb can remain numb for several hours after surgery, providing The limb can remain numb for several hours after surgery, providing excellent pain relief.excellent pain relief.

Deep and superficial structures of the limb are similarly anesthetized, Deep and superficial structures of the limb are similarly anesthetized, allowing extensive allowing extensive surgical exploration and correction to occur. This is in and correction to occur. This is in contrast to locally injected local anesthetics, which tend only to numb contrast to locally injected local anesthetics, which tend only to numb superficial structures in the immediate vicinity of the injection.superficial structures in the immediate vicinity of the injection.

Brachial plexus blockade Brachial plexus blockade Brachial plexus blockade is the preferred anesthetic technique when:Brachial plexus blockade is the preferred anesthetic technique when: Surgery is expected to be limited either to a region between the Surgery is expected to be limited either to a region between the

midpoint of the midpoint of the humerus and the and the fingers (in which case the brachial (in which case the brachial plexus block should be either a plexus block should be either a supra-clavicular, , infra-clavicular, , subcoracoid, or axillary block), OR surgery is expected to be limited to a subcoracoid, or axillary block), OR surgery is expected to be limited to a region between the midpoint of the humerus and the shoulder (in which region between the midpoint of the humerus and the shoulder (in which case the brachial plexus block should be an interscalene block). case the brachial plexus block should be an interscalene block). Because of the distribution of the local anesthetics on the various Because of the distribution of the local anesthetics on the various portions of the brachial plexus, surgeries crossing the midpoint of the portions of the brachial plexus, surgeries crossing the midpoint of the humerus often reveal patchy, unanesthetized portions of the arm. Such humerus often reveal patchy, unanesthetized portions of the arm. Such procedures probably should not be performed under regional nerve procedures probably should not be performed under regional nerve block alone.block alone.

ANDAND There are no contra-indications to a block such as infection at the There are no contra-indications to a block such as infection at the

intended injection site, significant intended injection site, significant anti-coagulation, , allergy or or hypersensitivity to local anesthetic medications, or disproportionate risk to local anesthetic medications, or disproportionate risk in the event of a local anesthetic toxic reaction (in the event of a local anesthetic toxic reaction (seizure) such as gastric ) such as gastric aspiration in a patient who has not adequately fasted,aspiration in a patient who has not adequately fasted,

ANDAND There will not be a need to perform a neurologic examination There will not be a need to perform a neurologic examination

immediately following the surgical procedure,immediately following the surgical procedure, ANDAND Patient prefers this technique over other available and reasonable Patient prefers this technique over other available and reasonable

approaches.approaches.

InjuriesInjuries

Two injuries types are recognised in brachial plexus Two injuries types are recognised in brachial plexus injuries: Traumautic and Obstetric.injuries: Traumautic and Obstetric.

Traumatic injuries often are the result of high velocity Traumatic injuries often are the result of high velocity RTA's (Road Traffic Injuries). The most common form RTA's (Road Traffic Injuries). The most common form of injury are the motorcycle drivers falling, with either of injury are the motorcycle drivers falling, with either the head/neck pushed to the side (upper plexus the head/neck pushed to the side (upper plexus lesions) or with their arm abducted (stretched lesions) or with their arm abducted (stretched upwards) which produces a lower plexus injury.upwards) which produces a lower plexus injury.

The brachial plexus is susceptible to injuries that The brachial plexus is susceptible to injuries that produce abduction of the thoracic limb from the body produce abduction of the thoracic limb from the body wall or a direct blow to the lateral surface of the wall or a direct blow to the lateral surface of the scapula.scapula.

The cardinal signs of brachial The cardinal signs of brachial plexus avulsion are:plexus avulsion are:

a weakness in the arma weakness in the arm diminished reflexesdiminished reflexes corresponding sensory deficitscorresponding sensory deficits The nerve roots are stretched or torn from their origin by The nerve roots are stretched or torn from their origin by

this trauma, since the meningeal coverings of the nerve this trauma, since the meningeal coverings of the nerve roots are thinner than those in the peripheral nerve. The roots are thinner than those in the peripheral nerve. The epineurium of the peripheral nerve is contiguous with the epineurium of the peripheral nerve is contiguous with the dural mater, providing extra support to the peripheral dural mater, providing extra support to the peripheral nerves. In cases where the nerve roots have been torn, nerves. In cases where the nerve roots have been torn, recovery is unlikely without new experimental surgical recovery is unlikely without new experimental surgical techniques.techniques.

The diagnosis may be confirmed by an EMG examination in The diagnosis may be confirmed by an EMG examination in 5-7 days. The evidence of denervation will be evident. If 5-7 days. The evidence of denervation will be evident. If there is no nerve conduction 72 hours after the injury, then there is no nerve conduction 72 hours after the injury, then avulsion is most likely.avulsion is most likely.

Brachial Plexus and Nerves of Upper limb

Supraclavicular nerve Origin Muscle distribution

Dorsal scapular Ventral rami of C4, C5 Rhomboids & Lev. scapulae

Long thoracic Ventral rami of C4- C7 Serratus anterior

Nerve to subclavius Superior trunk, C4- C6 Subclavius, sternoclavicular joint

Suprascapular Superior trunk, C4-C6 Supraspinatus, infraspinatus, glenohumeral (shldr) joint

Infraclavicular nerves

Origin Muscle distribution

Lateral pectoral Lateral cord, C5-C7 Pectoralis major, pectoralis minor

Musculocutaneous

Lateral cord, C5-C7 Coracobrachialis, biceps brachii, brachialis,

Median Lateral cord, C6-C7 Flexor carpi ulnaris, flexor digitorum profundus

Medial pectoral Medial cord, C8-T1 Pectoralis major/minor

Medial brachial cutaneous

Medial cord C8-T1 Skin on medial side of arm.

Medial antebrachial cutaneous

Medial cord, C8-T1 Skin over medial side of forearm

Infraclavicular nerve

Origin Muscle distribution

Ulnar Terminal of medial cord, C7, C8- T1

Half of flexor forearm muscles, small muscles of hand, skin on medial of hand to ring finger

Upper subscapular Posterior cord, C5-C6 Superior subscapularis

Thoracodorsal Posterior cord, C6-C8 Latissimus dorsi

Lower subscapular

Posterior cord, C5-C6 Inferior subscapularis and teres major

Axillary Terminal posterior cord, C5- C6

Teres minor, deltoids, shoulder joints, skin over inferior deltoids.

Radial Terminal posterior cord, C5- C6

Triceps brachii, anconeus, brachioradialis, extensor muscles of forearm, skin over post. Aspect of arm and forearm.

Muscle Origin Insertion Nerve Action

Biceps brachii Coracoid process, supraglenoid tubercle

Radial tuberosity, biciptal aponeurosis

MusculocutaneousC5 – C6

Supinates forearm, flexes forearm

Brachialis Anterior surface of distal humerus

Coronoid process, ulna tuberosity

MusculocutaneousC5 – C6

Flex and adducts arms

Cracobrachialis Coronoid process of scapula

Mid3rd medial surface humerus

MusculocutaneousC5 – C7

Flex and adducts arm

Triceps brachii LH:Infraglenoid tubercleLat hd: post humerus sup. To radial grooveMedial Hd: post. Humerus inf. To radial groove

Olecranon of ulna and fascia of forearm

Radial nerve C6 – C8

Extend forearm, long head steadies head of humerus

Anconeus Lateral epicondyle Humerus

Lat. Surface olecranon sup of ulna

Radial nerve C7 – T1

Assist triceps to extend forearm, stabilize elbow, adducts ulna in pronation

BreakBreak

Axillary arteryAxillary artery

Boundaries = lateral border first rib to superior border of Teres minor Boundaries = lateral border first rib to superior border of Teres minor musclemuscle

Division:Division: 1st division = from lateral border first rib to medial border of pectoralis 1st division = from lateral border first rib to medial border of pectoralis

minorminor Branch Branch = supreme thoracic artery= supreme thoracic artery 2nd division = from medial border of pectoralis muscle to lateral border of 2nd division = from medial border of pectoralis muscle to lateral border of

same musclesame muscle BranchBranch = = Thoraco acromial arteryThoraco acromial artery Lateral thoracic arteryLateral thoracic artery 3rd division = from lateral border of pectoralis minor to superior border of 3rd division = from lateral border of pectoralis minor to superior border of

the Teres minor musclethe Teres minor muscle Branch = Branch = Subscapular arterySubscapular artery Anterior circumflex humeral arteryAnterior circumflex humeral artery Posterior circumflex humeral arteryPosterior circumflex humeral artery

Brachial arteryBrachial artery

BoundariesBoundaries = distal edge of Teres major muscle to = distal edge of Teres major muscle to Cubital Cubital

fossa.fossa. Branches Branches = 1. Deep brachial or Profunda brachii artery = 1. Deep brachial or Profunda brachii artery

= to = to posterior compartment of the armposterior compartment of the arm Recurrent branch anastomose with the posterior circumflex Recurrent branch anastomose with the posterior circumflex

humeral arteryhumeral artery Lateral branch anastomose with the Radial recurrent artery.Lateral branch anastomose with the Radial recurrent artery. Posterior branch anastomose with Recurrent interosseous Posterior branch anastomose with Recurrent interosseous

artery.artery. Collateral branchesCollateral branches

Superior ulnar artery anastomose with posterior recurrent Superior ulnar artery anastomose with posterior recurrent ulnar artery.ulnar artery.

Inferior ulnar artery anastomose with anterior recurrent ulnar Inferior ulnar artery anastomose with anterior recurrent ulnar artery.artery.

Venous returnVenous return

Deep veins = 2 to 3 joins to form the venae Deep veins = 2 to 3 joins to form the venae comitantes brachiales freely anastomose about comitantes brachiales freely anastomose about the brachial artery.the brachial artery.

superficial veinssuperficial veins Cephalic veins to the anterior of the lateral epicondyle Cephalic veins to the anterior of the lateral epicondyle

to the deltopectoral triangle, pierces the clavipectoral to the deltopectoral triangle, pierces the clavipectoral fascia to join the axillary vein distal to first rib..fascia to join the axillary vein distal to first rib..

Basilic vein = medial epicondyle along the deep Basilic vein = medial epicondyle along the deep medial antebrachial joins the brachial vein near the medial antebrachial joins the brachial vein near the teres major muscle to form the axillary veins.teres major muscle to form the axillary veins.

Median cubital veins = the connecting veins Median cubital veins = the connecting veins between the cephalic and the basilica veins at between the cephalic and the basilica veins at the cubital the cubital

Fossa, it lies at the bicipital aponeurosis..Fossa, it lies at the bicipital aponeurosis..

Lymphatic drainageLymphatic drainage

Deep lymphatics accompany brachial Deep lymphatics accompany brachial veins into the axillary lymph nodes.veins into the axillary lymph nodes.

Superficial lymphatics along the Superficial lymphatics along the superficial veins into the:superficial veins into the: supratrochlear lymph nodes near the supratrochlear lymph nodes near the

medial epicondylemedial epicondyle superficial drainage bypass most axillary superficial drainage bypass most axillary

nodes into the subclavian vein.nodes into the subclavian vein.

Ligaments of the Ligaments of the Glenohumeral Joint.Glenohumeral Joint.

There are several important ligaments in the There are several important ligaments in the shoulder. Ligaments are soft tissue structures shoulder. Ligaments are soft tissue structures that connect bones to bones. A joint capsule is that connect bones to bones. A joint capsule is a watertight sac that surrounds a joint. In the a watertight sac that surrounds a joint. In the shoulder, the joint capsule is formed by a shoulder, the joint capsule is formed by a group of ligaments that connect the humerus group of ligaments that connect the humerus to the glenoid. These ligaments are the main to the glenoid. These ligaments are the main source of stability for the shoulder. They help source of stability for the shoulder. They help hold the shoulder in place and keep it from hold the shoulder in place and keep it from dislocating. These are the glenohumeral dislocating. These are the glenohumeral ligaments (GHL) ligaments (GHL)

Another ligament links the coracoid to the Another ligament links the coracoid to the acromion - coracoacromial ligament (CAL). This acromion - coracoacromial ligament (CAL). This ligament can thicken and cause Impingement ligament can thicken and cause Impingement Syndrome Syndrome

Ligaments attach the clavicle to the acromion Ligaments attach the clavicle to the acromion in the AC joint. in the AC joint.

Two ligaments connect the clavicle to the Two ligaments connect the clavicle to the scapula by attaching to the scapula by attaching to the coracoid process, coracoid process, a a bony ridge on the scapula - coracoclavicular bony ridge on the scapula - coracoclavicular ligaments (CCL) ligaments (CCL)

Ligaments of the Shoulder Complex: Ligaments of the Shoulder Complex: CCL - coracoclavicular ligamentsCCL - coracoclavicular ligaments CAL - coracoacromial ligaments CAL - coracoacromial ligaments SGHL - Superior GlenoHumeral Ligament SGHL - Superior GlenoHumeral Ligament MGHL - Muperior GlenoHumeral Ligament MGHL - Muperior GlenoHumeral Ligament IGHL - Inferior GlenoHumeral LigamentIGHL - Inferior GlenoHumeral Ligament

Ligaments of the Rotator Ligaments of the Rotator CuffCuff

The tendons of the rotator cuff are the next The tendons of the rotator cuff are the next layer in the shoulder joint. Tendons are much layer in the shoulder joint. Tendons are much like ligaments, except that tendons attach like ligaments, except that tendons attach muscles to bone. Muscles move the bones by muscles to bone. Muscles move the bones by pulling on the tendons. One important tendon pulling on the tendons. One important tendon that travels through the shoulder joint is the that travels through the shoulder joint is the biceps tendon biceps tendon . . The biceps tendon actually The biceps tendon actually begins at the top of the shoulder socket (the begins at the top of the shoulder socket (the glenoid) and then passes across the front of glenoid) and then passes across the front of the shoulder to connect to the biceps muscle. the shoulder to connect to the biceps muscle. (The biceps is the muscle that weightlifters (The biceps is the muscle that weightlifters are always showing off). are always showing off).

The The rotator cuff rotator cuff tendons are a group of four tendons are a group of four tendons that connect the deepest layer of tendons that connect the deepest layer of muscles to the humerus.  They are the muscles to the humerus.  They are the tendons of the rotator cuff muscles (left) tendons of the rotator cuff muscles (left)

Tendons of the shoulder: Tendons of the shoulder: From front to back: From front to back: Subscapularis Subscapularis Biceps Tendon Biceps Tendon Supraspinatus Supraspinatus Infraspinatus Infraspinatus Teres MinorTeres Minor

Muscles of the shoulderMuscles of the shoulder

There are 30 muscles providing There are 30 muscles providing movement and support for the movement and support for the shoulder complex. 15 muscles shoulder complex. 15 muscles move and stabilize the scapula; 9 move and stabilize the scapula; 9 muscles provide for glenohumeral muscles provide for glenohumeral joint motion; and 6 support the joint motion; and 6 support the scapula on the thorax scapula on the thorax

There are three important groups There are three important groups of muscles around the shoulder: of muscles around the shoulder:

1. Surface muscles (Extrinsic): 1. Surface muscles (Extrinsic): The large The large deltoid deltoid muscle forms muscle forms

the outer layer of muscle. This is the outer layer of muscle. This is the largest, strongest muscle of the largest, strongest muscle of the shoulder. The deltoid muscle the shoulder. The deltoid muscle takes over lifting the arm once the takes over lifting the arm once the arm is away from the side. arm is away from the side.

Pectoralis Major provides Pectoralis Major provides movement and support in the movement and support in the front of the shoulder front of the shoulder

Deep ( Intrinsic) musclesDeep ( Intrinsic) muscles

. Deep muscles (Intrinsic): . Deep muscles (Intrinsic): The rotator cuff tendons attach to the deep rotator cuff The rotator cuff tendons attach to the deep rotator cuff

muscles. These 4 muscles are involved in raising the arm muscles. These 4 muscles are involved in raising the arm from the side and rotating the shoulder in the many from the side and rotating the shoulder in the many directions. The rotator cuff mechanism also helps keep the directions. The rotator cuff mechanism also helps keep the shoulder joint stable by holding the humeral head in the shoulder joint stable by holding the humeral head in the glenoid socket. These muscles are: subscapularis, glenoid socket. These muscles are: subscapularis, supraspinatus, infraspinatus and teres minor. supraspinatus, infraspinatus and teres minor.

3. Back Muscles (Posterior): 3. Back Muscles (Posterior): These muscles are at the back of the shoulder that stabilise These muscles are at the back of the shoulder that stabilise

and move the scapula on the trunk of the body. This group and move the scapula on the trunk of the body. This group includes the trapezius, rhomboids, levator scapulae, and includes the trapezius, rhomboids, levator scapulae, and the serratus anterior muscles; and are concerned with the serratus anterior muscles; and are concerned with stabilisation and rotation of the scapula. stabilisation and rotation of the scapula.

Bursas of the Shoulder Bursas of the Shoulder

Sandwiched between the rotator cuff Sandwiched between the rotator cuff muscles and the outer layer of large muscles and the outer layer of large bulky muscles is a structure known as bulky muscles is a structure known as a a bursa. bursa. Bursae are everywhere in the Bursae are everywhere in the body. They are found wherever two body. They are found wherever two body parts move against one another body parts move against one another and there is no joint to reduce the and there is no joint to reduce the friction. A bursa is simply a sac friction. A bursa is simply a sac between two moving surfaces that between two moving surfaces that contains a small amount of lubricating contains a small amount of lubricating fluid. fluid.

Think of a bursa like this: If you press Think of a bursa like this: If you press your hands together and slide them your hands together and slide them against one another, you produce against one another, you produce some friction. In fact, when your hands some friction. In fact, when your hands are cold you may rub them together are cold you may rub them together briskly to create heat from the friction. briskly to create heat from the friction. Now imagine that you hold in your Now imagine that you hold in your hands a small plastic sack that hands a small plastic sack that contains a few drops of salad oil. This contains a few drops of salad oil. This sack would let your hands glide freely sack would let your hands glide freely against each other without a great against each other without a great deal of friction. deal of friction.

Muscles of the BackMuscles of the Back

Superficial musclesSuperficial muscles

MuscleMuscle OriginOrigin InsertioInsertionn

Action Action Nerve Nerve

TrapeziusTrapezius Occiput, Occiput, nuchal linenuchal line

Clavicle, Clavicle, acromion, acromion, spine of spine of scapulascapula

Rotator, Rotator, adductor, adductor, lowers the lowers the scapula. scapula.

Spinal Spinal accessory accessory nervenerve

Latissimus Latissimus dorsidorsi

Thoraco-Thoraco-Lumbar Lumbar fascia,spinfascia,spines of es of lumbar & lumbar & sacral, iliac sacral, iliac crest, crest, lower 4 lower 4 ribsribs

IntertuberIntertubercular cular groove or groove or bicipital bicipital groove.groove.

Extends, Extends, adducts, adducts, median median rotator of rotator of shouldershoulder

ThoracoThoraco

dorsal dorsal ( long ( long subscapulasubscapular)r)

Superficial, rhomboid Superficial, rhomboid layer…layer…

MuscleMuscle OriginOrigin InsertioInsertionn

Action Action Nerve Nerve

Levator Levator scapulascapula

Post, Post, tubercle tubercle and and transverse transverse process process

C1-4C1-4

Medial Medial border border scapula, scapula, higherhigher

Elevator Elevator and rotator and rotator of scapulaof scapula

Dorsal Dorsal scapular scapular nervenerve

Rhomboid Rhomboid minorminor

Nuchal lig. Nuchal lig. Spine C7-Spine C7-T1T1

Medial Medial border border scapula, scapula, lowerlower

Adduct Adduct scapula scapula medially, medially, depressor depressor of scapulaof scapula

Dorsal Dorsal scapular scapular nervenerve

Rhomboid Rhomboid majormajor

Spine T2 – Spine T2 – T5, T5, supraspinousupraspinous lig.s lig.

Medial Medial border border lowerlower

Adduct Adduct scapula scapula medially, medially, depressor depressor

Dorsal Dorsal scapular scapular nervenerve

Deep muscles of the back, Deep muscles of the back, transverse- costal grouptransverse- costal group

Splenius capitis – Splenius capitis – from nuchal lig, spine of C7, T1-3 to occiput , from nuchal lig, spine of C7, T1-3 to occiput , mastoidmastoid

Splenius cervicis – Splenius cervicis – spines of T3-6 to transverse process C1-3spines of T3-6 to transverse process C1-3

Erector spinae – Erector spinae – med crest of scarum to lower 6 ribsmed crest of scarum to lower 6 ribs Iliocostalis lumborumIliocostalis lumborum – – from spines T11 – L5, iliac crest to sacrumfrom spines T11 – L5, iliac crest to sacrum Iliocostalis thoracisIliocostalis thoracis- from lower 6 rib angle to rib 1-6/trnsvrs proc. - from lower 6 rib angle to rib 1-6/trnsvrs proc.

C7 C7 Iliocostalis cervicisIliocostalis cervicis- angle rib 3-6 to trnsvrs poc. C4-6- angle rib 3-6 to trnsvrs poc. C4-6 Longissimus thoracis- Longissimus thoracis- mid crest sacrummid crest sacrum Longissimus cervicis- Longissimus cervicis- transvrs proc T1 - 5transvrs proc T1 - 5 Longissimus capitis- Longissimus capitis- transvrs proc. T1- 5, artic. Proc C5 - 7transvrs proc. T1- 5, artic. Proc C5 - 7 Spinalis thoracisSpinalis thoracis- spines T11 – L2- spines T11 – L2 Spinalis cervicisSpinalis cervicis- - C7 to spine C2C7 to spine C2

Deep layer, Transverse-spinal Deep layer, Transverse-spinal groupgroup

Semispinalis thoracisSemispinalis thoracis – – transvrs proc. T6 -10 to spines C6-T4 transvrs proc. T6 -10 to spines C6-T4 Semispinalis cervicisSemispinalis cervicis – transvrs proc. T1-T6, to spines C2-C5– transvrs proc. T1-T6, to spines C2-C5 Semispinalis capitisSemispinalis capitis – Transvrs proc. C7-T7, to nuchal plane of occiput – Transvrs proc. C7-T7, to nuchal plane of occiput Spinalis capitisSpinalis capitis- transvrs proc. C7-T7, to nuchal plane occiput- transvrs proc. C7-T7, to nuchal plane occiput Multifidus Multifidus

Sacral – post sacrum to spines o C2 – L5Sacral – post sacrum to spines o C2 – L5 Lumbar – mamillary proc.Lumbar – mamillary proc. Thoracic – from transvrs processThoracic – from transvrs process Cervical – from articular proc C4 – C7Cervical – from articular proc C4 – C7

RotatoresRotatores Longi – transvrs proc of 1 vertebra to spine 2 vertebra aboveLongi – transvrs proc of 1 vertebra to spine 2 vertebra above Breves – transvrs proc of 1 vertebra to next vertebra above Breves – transvrs proc of 1 vertebra to next vertebra above Interspinalis – connects apices of spines of adjoining vertebraInterspinalis – connects apices of spines of adjoining vertebra Intertransverse- interconnects anterior tubercle of transvrs processIntertransverse- interconnects anterior tubercle of transvrs process

Suboccipital muscleSuboccipital muscle

Rectus capitis posterior majorRectus capitis posterior major From spinous process of axis, to inf nuchal line. Extend and From spinous process of axis, to inf nuchal line. Extend and

rotate the head to same siderotate the head to same side Tubercle post arch of atlas, to inf nuchal line. Extends head.Tubercle post arch of atlas, to inf nuchal line. Extends head.

• Rectus capitis posterior minorRectus capitis posterior minor Tubercle on post arch atlas to inferior nuchal line.Tubercle on post arch atlas to inferior nuchal line. Extends head.Extends head.

Obliquus capitis inferiorObliquus capitis inferior apex, and spine of atlasTrnsvrse proc. Atlas, turns head same sideapex, and spine of atlasTrnsvrse proc. Atlas, turns head same side

• Obliquus capitis superiorObliquus capitis superior Transvrs proc. Atlas to occipital bone between nuchal lines.Transvrs proc. Atlas to occipital bone between nuchal lines. Extends head and bends it to same side.Extends head and bends it to same side.

Actions, general….Actions, general….

Nerve supply by all posterior primary divisions of spinal nerves.Nerve supply by all posterior primary divisions of spinal nerves. Splenius – draws head back, bends head laterally, rotates ace to Splenius – draws head back, bends head laterally, rotates ace to

same side.same side. Iliocostalis- bends vertebral column to side, lumborum depress Iliocostalis- bends vertebral column to side, lumborum depress

ribsribs Longissimus thoracis and cervicis bends Longissimus thoracis and cervicis bends column to side, depress column to side, depress

ribsribs Longissimus Longissimus capitis extends head, bends head to side, rotates face to capitis extends head, bends head to side, rotates face to

same sidesame side Semispinalis thoracis & cervicisSemispinalis thoracis & cervicis- rotates column to same side.- rotates column to same side. Semispinalis capitis – extends head rotates head to opposite side.Semispinalis capitis – extends head rotates head to opposite side. Multifidus rotates column to opposite side.Multifidus rotates column to opposite side. Rotatores rotates column to opposite side.Rotatores rotates column to opposite side. Intertransverse bends column to same side.Intertransverse bends column to same side.

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