Frontalis◦O: Frontal Bone◦I: eyebrow skin◦Action: elevates

eyebrows

Orbicularis oculi◦Sphincter muscle of eyelid◦O: frontal & maxillary bones◦I: tissue of eyelid◦Action: closes eye◦Nerve: facial / CN VII

(11.6)

Orbicularis oris◦Sphincter muscle

around mouth◦O: Maxilla;

mandible◦I: skin around

mouth◦Action: closes/

protrudes lips

Zygomaticus ◦O: zygomatic bone◦I: corners of mouth◦Action: smiling◦Nerve: facial / CN VII

(11.6)

Major and Minor

Platysma◦Broad plate-like

muscle◦O: chest fascia◦I: mandible; skin at

corners of mouth◦Action: depresses

mandible, pulls lower lip down

Masseter ◦O: zygomatic arch◦I: angle & ramus of

mandible◦Action: elevate

mandible◦Nerve: trigeminal

nerve / CN V (foramen ovale)

(11.7a)

Masseter

Temporalis ◦O: temporal fossa◦I: coronoid

process of mandible

◦Action: elevate and retract mandible

◦Nerve: trigeminal n. / CN V

(11.7a)

Buccinator◦O: molar area of

mandible/ maxilla

◦I: orbicularis oris◦Action:

compresses cheek

Sternocleidomastoid ◦O: manubrium &

medial clavicle◦I: mastoid process of

temporal bone◦Action: head & neck

flexion, rotate head contralaterally

◦Nerve: accessory n. / CN XI

(11.8a)

Sternocleidomastoid

Styloglossus ◦ O: styloid process of

temporal bone◦ I: tongue◦ Action: retract & elevate

tongue◦ Nerve: hypoglossal n. /

CN XII

(11.7c)

Styloglossus

Hyoglossus ◦ O: hyoid bone◦ I: tongue◦ Action: depresses

tongue◦ Nerve: hypoglossal n. /

CN XII

(11.7c)

Hyoid bone

Digastric ◦ two muscle bellies with an

intermediate tendon attached to the hyoid bone

◦ O: inferior margin of mandible (anterior belly); mastoid process of temporal bone (posterior belly)

◦ I: hyoid bone◦ Action: elevate hyoid, stabilize

hyoid, depress mandible◦ Nerve: trigeminal n. / CN V

(anterior belly), facial n. / CN VII (posterior belly)

(11.8a)Anterior belly Posterior belly

Stylohyoid ◦ O: styloid process of

temporal bone◦ I: hyoid bone◦ Action: elevate &

retract hyoid, swallow◦ Nerve: facial n. / CN VII

(11.7c)

Stylohyoid

Sternohyoid ◦ O: manubrium &

medial end of clavicle

◦ I: hyoid bone◦ Action: depress

hyoid

(11.8a)

Sternohyoid

Pharyngeal constrictors ◦ O: mandible, pterygoid

process, hyoid, laryngeal cartilages

◦ I: posterior medial raphe of pharynx

◦ Action: peristaltic contraction / swallow

(11.8b)

Superior

Middle

Inferior

Gluteus muscles◦ Maximus

O: post. Ilium/ sacrum; I: gluteal tuberosity

Action: thigh extension; ext. rotation; abduction

◦ Medius O: post. Ilium; I: gluteal tuberosity Action: thigh abduction

◦ Minimus (deep) O: post. Ilium; I: gluteal tuberosity Action: thigh abduction

Gluteus muscles◦Minimus (deep)

O: post. Ilium; I: gluteal tuberosity

Action: thigh abduction

Hip & knee muscles

Hip & knee muscles Adductors

– O: Ischium/ pubis– I: femur– Action: adduct

thigh Sartorius

– O: ant. Iliac crest– I: medial tibial

tuberosity– Action: thigh

flexion; abduction; ext. rotation

Hip & knee muscles Tensor fasciae latae

– O: Iliac crest– I: lateral condyle tibia– Action: thigh abduction

Iliopsoas– O: ilium– I: lesser trochanter– Action: thigh flexion (P.M.)

Gracilis– O: pubis; I: prox. medial

tibia– Action: adduct thigh

Quadriceps femoris ◦O: Proximal

femur◦I: tibial

tuberosity via patellar tendon

◦Action: extend knee, flex thigh

Quadriceps femoris ◦O: Proximal

femur◦I: tibial

tuberosity via patellar tendon

◦Action: extend knee, flex thigh

Vastuslateralis

Vastusintermedius

Vastusmedialis

Patella

Patellarligament

Rectus femoristendon (cut)

Hamstrings◦O: ischial

tuberosity◦I: posterior

proximal tibia◦Action: extend

thigh, flex knee

Tibialis anterior◦ O: lateral condyle and shaft

of tibia◦ I: tarsal and first metatarsal

bones◦ Action: dorsiflexion

Extensor digitorum longus◦ O: lat. Condyle tibia; I:

phalanges 2-5◦ Action: extends toes,

dorsiflexion

Gastrocnemius ◦O: medial & lateral

condyles of femur◦I: calcaneus via Achilles

tendon◦Action: plantar flexion, flex knee

Soleus ◦ plantar flexion

Fibularis◦ plantar flexion, eversion

Spinalis ◦ O: spines of upper

lumbar and lower thoracic vertebrae

◦ I: spines of upper thoracic and cervical vertebrae

◦ Action: extends vertebral column

(11.9d)

External & internal intercostals ◦ O&I: inferior &

superior border of ribs ◦ Action: inspiration and

expiration

(11.10a)

Internal

Diaphragm ◦ O: xiphoid process, ribs

10-12, lumbar vertebrae

◦ I: central tendon◦ Action: flattens on

contraction (inspiration)

◦ Nerve: phrenic nerves

(11.10b)

Xiphoid process

Rectus abdominis ◦ O: pubic crest &

symphysis◦ I: xiphoid process and

costal cartilages of ribs 5-7

◦ Action: flex & rotate lumbar vertebrae, stabilize pelvis during walking, increase intraabdominal pressure

◦ Note: 3 tendinous insertions, aponeurosis & linea alba (11.11ab)

Oblique◦ Internal◦ external

Transverse

Trapezius ◦ O: occipital bone, C7-

T12 spinous processes◦ I: acromion, spine of

scapula, lateral 1/3 of clavicle

◦ Action: elevate, adduct, depress scapula, extend head

(11.13b)

POSTERIORVIEW

Latissimus dorsi◦ O: Fascia spines T7-

L5◦ I: intertuburcular

groove humerus◦ Action: PM arm

extension, adduction arm

Rhomboid◦ O: spinous process C7-

T5◦ I: medial scapula◦ Action: adduct scapula

Levator scapulae◦ O: Transverse process

C1-C4◦ I: medial border

scapula◦ Action: elevate scapula

Deltoid ◦ O: lateral clavicle,

acromion & spine of scapula

◦ I: deltoid tuberosity of humerus

◦ Action: arm-abduction, flexion, extension, medial & lateral rotation

(11.13ab)

Anterior

Posterior

Teres major O: medial inferior

scapula I: intertuburcular

groove humerus (ant. side)

Action: medial arm rotation, adducts arm

Shoulder musclesShoulder muscles

Act to stabilize head of humerus in glenoid cavity and prevent dislocation

S.I.T.S.

◦Supraspinatous◦Infraspinatus ◦Teres minor◦Subscapularis

Infraspinatus◦ O: infraspinous fossa◦ I: greater tubercle of

humerus◦ Action: lateral rotate

humerus Teres minor

◦ O: inf. lat. Border scapula

◦ I: greater tubercle◦ Action: lateral rotate

humerus

(11.14b)

POSTERIORVIEW

Supraspinatus◦ O: Supraspinous fossa◦ I: greater tubercle◦ Action: abduction

humerus

POSTERIORVIEW

Subscapularis ◦ O: subscapular fossa◦ I: lesser tubercle of

humerus◦ Action: medial rotate

arm

ANTERIORVIEW

Pectoralis major ◦ O: medial clavicle,

sternum, cartilage of ribs 1-6

◦ I: intertubucular groove humerus

◦ Action: arm-flexion, medial rotation, adduction

(11.13a)

-Nerve: Medial and lateral pectoral nerves (C6-C8)

Pectoralis minor ◦ O: anterior surface of

ribs 3-5◦ I: coracoid process of

scapula◦ Action: with ribs fixed,

pulls scapula anterior & inferior; with scapula fixed, pulls ribs superiorly

◦ Nerve: Medial and lateral pectoral nerves (C6-C8)

(11.13a)

Triceps brachii ◦ O: long head-

infraglenoid tubercle, lat. & med. heads-posterior shaft of humerus

◦ I: olecranon process of ulna

◦ Action: extend forearm, assist adduction of arm

◦ Nerve: Radial nerve (11.14b)

Biceps brachii ◦ O: short head-coracoid

process, long head-tubercle above glenoid cavity and lip of glenoid cavity (intertubercular groove)

◦ I: radial tuberosity◦ Action: flex elbow, supinate

forearm, weak arm flexor◦ Nerve: Musculocutaneous

nerve (C5 & C6)

(11.14c)

Serratus anterior ◦ O: ribs 1-9◦ I: medial border of

scapula◦ Action: hold scapula

against chest wall, moves inferior angle of scapula lateral & superior (abduction, pushing, punching)

(11.13a,8.1a reversed)

Superficial thorax muscles

Flexor carpi (radialis & ulnaris) ◦ O: medial epicondyle

of humerus, ulna◦ I: metacarpals and

carpals◦ Action: wrist flexion,

abduct & adduct hand

◦ Carpal tunnel (Median nerve) syndrome p. 184

(11.15a)Anterior view

radialis

ulnaris

Extensor carpi◦ O: lateral epicondyle of

humerus◦ I: base of metacarpals ◦ Action: extend, abduct,

and adducts wrist◦ Palpate forearm

muscles