MUSCLES OF THE UPPER AND LOWER LIMBS

SCAPULAR/SHOULDER REGION

MUSCLE	ORIGIN	INSERTION	NERVE SUPPLY	ACTIONS
Trapezius	Medial third of the superior nuchal line of the occipital bone, external occipital protuberance, ligamentum nuchae, and spinous processes of vertebrae C7 to T12	Spine of the scapula, the acromion, and lateral third of the clavicle	Spinal root of the accessory nerve provides motor supply, fibers from spinal nerves C3 and C4 provide for proprioception	Upper fibers raise the pectoral girdle, middle fibers retract the pectoral girdle, and lower fibers lower the pectoral girdle; upper and lower fibers act together to laterally rotate the scapula
Levator scapulae	Transvers processes of vertebrae C1 to C4	Medial border of the supraspinous fossa of the scapula	Dorsal scapular nerve (C5) and fibers from spinal nerves C3 and C4	Raises the pectoral girdle and medially rotates the scapula
Rhomboid minor	Ligamentum nuchae and spinous processes of vertebrae C7 and T1	Medial border of the scapula near the medial end of the spine of the scapula	Dorsal scapular nerve (C5)	Raises and retracts the pectoral girdle and medially rotates the scapula
Rhomboid major	Spinous processes of vertebrae T2 to T5	Medial border of the infraspinous fossa of the scapula	Dorsal scapular nerve (C5)	Raises and retracts the pectoral girdle and medially rotates the scapula
Serratus anterior	Outer surfaces of the anterolateral portions of ribs 1-8	Anterior aspect of the medial obrder of the scapula	Long thoracic nerve (C5, C6, C7)	Protracts the pectoral girdle and laterally rotates the scapula
Pectoralis minor	Outer surfaces of ribs 3-5	Coracoid process of the scapula	Medial and lateral pectoral nerves (C6, C7, C8)	Lowers and protracts the pectoral girdle and medially rotates the scapula
Subclavius	First costal cartilage	Inferior surface of the clavicle	Nerve to subcalvius (C5 and C6)	Lowers the pectoral girdle
Supraspinatus	Supraspinous fossa of the scapula	Capsule of the shoulder joint and greater tuberosity of the humerus	Suprascapular nerve (C5 and C6)	Abducts the arm
Infraspinatus	Infraspinous fossa of the scapula	Capsule of the shoulder joint and greater tuberosity of the humerus	Suprascapular nerve (C5 and C6)	Externally rotates the arm
Teres minor	upper lateral border of the scapula	Capsule of the shoulder joint and greater tuberosity of the humerus	Axillary nerve (C5 and C6)	Externally rotates the arm
Subscapularis	Subscapular fossa of the scapula	Capsule of the shoulder joint and lesser tuberosity of the humerus	Upper and lower subscapular nerves (C5, C6, C7)	Internally rotates the arm
Deltoid	Lateral third of the clavicle, acromion, and spine of the scapula	Deltoid tuberosity of the humerus	Axillary nerve (C5 and C6)	Anterior fibers flex and internally rotate the arm, middle fibers abject the arm, and posterior fibers extend and externally rotate the arm
Pectoralis major	Medial half of the clavicle, sternum, and costal cartilages of ribs 2-6	Lateral lip of the intertubercular groove of the humerus	Medial and lateral pectoral nerves; clavicular head (C5 and C6); sternocostal head (C7, C8, T1)	Adducts and internally rotates the armmm; clavicular fibers flex the arm
Teres major	Lower lateral border of the scapula	Medial lip of the intertubercular groove of the humerus	Lower subscapular nerve (C6, C7)	Adducts and internally rotates the arm
Latissimus dorsi	Posterior part of the iliac crest, thoracolumbar fascia, spinous processes of the lower 6 thoracic vertebrae, and ribs 9 or 10-12	Floor of the intertubercular groove of the humerus	Thoracodorsal nerve (C6, C7, C8)	Extends, adducts, and internally rotates the arm

BRACHIAL PLEXUS

Posterior Cord

Nerve	Muscles	Major joints
Upper subscapular	Subscapularis
Middle subscapular	Latissimus dorsi
Lower subscapular	Subscapularis Teres major
Axillary	Deltoid Teres minor	Shoulder
Radial	Triceps and anconeus Brachialis Brachioradialis Extensor carpi radialis longus Extensor carpi radialis brevis Supinator Extensor digitorum Extensor digiti minimi Extensor carpi ulnaris Abductor pollicis longus Extensor pollicis brevis Extensor pollicis longus Extensor indicis	Elbow Proximal radioulnar Distal radioulnar Wrist Carpometacarpal of thumb

Lateral Cord

Nerve	Muscles	Major joints
Lateral pectoral	Pectoralis major Pectoralis minor	Acromioclavicular Shoulder
Musculocutaneous	Coracobrachialis Biceps brachii Brachialis	Elbow Proximal radioulnar
Median	Pronator Teres Flexor carpi radialis Palmaris longus Flexor digitorum superficialis Flexor digitorum profundus-ltrl Pronator quadratus Flexor pollicis longus Abductor pollicis brevis Flexor pollicis breves Opponens pollicis First lumbrical Second lumbrical	Wrist Carpometacarpal of thumb Metacarpophalangeal all digits Interphalangeal of all digits

Medial Cord (less median nerve)

Nerve	Muscles	Major joints
Medial pectoral	Pectoralis major Pectoralis minor
Ulnar	Flexor carpi ulnaris Flexor digitorum profundus-Medl Palmaris brevis Abductor digiti minimi Flexor digiti minimi Opponens digiti minimi Third lumbrical Fourth lumbrical All 3 palmar interossei All 4 dorsal interossei Adductor pollicis	Wrist Carpometacarpal of thumb Metacarpophalangeal all digits Interphalangeal of all digits

Muscles of the Arm

Muscle	Origin	Insertion	Nerve supply	Actions
Coracobrachialis	Coracoid process of the scapula	Midregion of the medial aspect of the humeral shaft	Musculocutaneous	Flexes and adducts the arm
Biceps brachii	Long head from the supraglenoid tubercle of the scapula; short head from the coracoid process of the scapula	Radial tuberosity and deep fascia on the upper anteromedial side of the forearm	Musculocutaneous	Flexes and supinates the forearm
Brachialis	Lower half of the anterior surface of the humeral shaft	Coronoid process of the ulna	Musculocutaneous and radial to a small lateral part	Flexes the forearm
Triceps	Long head from the infraglenoid tubercle of the scapula; lateral head from the posterior surface of the humeral shaft above the spiral groove; medial head from the posterior surface of the humeral shaft below the spiral groove	Olecranon process of the ulna	Radial	Extends the forearm

Anterior Forearm Muscles

Muscle	Origin	Insertion	Nerve Supply	Actions
Pronator quadratus	Distal fourth of the anterior surface of the ulna	Distal fourth of the anterior surface of the radius	Median: anterior interosseous branch	Pronates the forearm
Pronator teres	Medial epicondyle of the humerus via the common flexor tendon and coronoid process of the ulna	Midregion of the lateral aspect of the radial shaft	Median	Pronates and flexes the forearm
Flexor carpi radialis	Medial epicondyle of the humerus via the common flexor tendon	Bases of the 2nd and 3rd metacarpals	Median	Flexes and abducts the hand
Palmaris longus	Medial epicondyle of the humerus via the common flexor tendon	Distal half of the anterior surface of the flexor retinaculum and central part of the palmar aponeurosis	median	Flexes the hand
Flexor carpi ulnaris	Medial epicondyle of the humerus via the common flexor tendon and the olecranon process and posterior border of the ulna	Pisiform, hamate, and 5th metacarpal	Ulnar	Flexes and abducts the hand
Flexor pollicis longus	Anterior surface of the radius and adjoining interosseous membrane	Base of the distal phalanx of the thumb	Median: Anterior interosseous branch	Flexes the phalanges of the thumb
Flexor digitorum superficialis	Medial epicondyle of the humerus via the common flexor tendon, ulnar collateral ligament of the elbow joint, coronoid process of the ulna, and anterior border of the radius	Sides of the middle phalanx of the medial four digits	Median	Flexes the middle and proximal phalanges of the medial four digits
Flexor digitorum profundus	Proximal 3/4 of the anterior and medial surfaces and posterior border of the ulna and proximal half of the anterior surface of the interosseous membrane	Base of the distal phalanx of the medial four digits	Medial part by ulnar; lateral part by median (ant. interosseous branch)	Flexes the distal phalanges of the medial four digits

Posterior Forearm Muscles

Muscle	Origin	Insertion	Nerve Supply	Actions
Anconeus	Posterior surface of the lateral epicondyle of the humerus	Lateral surface of the olecranon process of the ulna and upper posterior surface of the ulnar shaft	Radial	Extends the forearm
Brachioradialis	Proximal 2/3 of the lateral supracondylar ridge of the humerus	Lateral surface of the distal end of the radius	Radial	Flexes the forearm
Supinator	Lateral epicondyle of the humerus, radial collateral ligament of the elbow joint, annular ligament, and supinator crest of the ulna	Anterior, lateral, and posterior surfaces of the proximal third of the radius	Deep branch of the radial	Supinates the forearm
Extensor carpi radialis longus	Distal third of the lateral supracondylar ridge of the humerus	Base of the 2nd metacarpal	Radial	Extends and abducts the hand
Extensor carpi radialis brevis	Lateral epicondyle of the humerus via the common extensor tendon	Base of the 3rd metacarpal	Deep branch of the radial	Extends and abducts the hand
Extensor carpi ulnaris	Lateral epicondyle of the humerus via the common extensor tendon and the posterior border of the ulna	Base of the 5th metacarpal	Posterior interosseous	Extends and adducts the hand
Abductor pollicis longus	Posterior surfaces of the radius and ulna and interosseous membrane	Base of the 1st metacarpal	Posterior interosseous	Abducts the thumb and extens it at the carpometacarpal joint
Extensor pollicis brevis	Posterior surface of the radius and interosseous membrane	Base of the proximal phalanx of the thumb	Posterior interosseous	Extends the thumb at the metacarpophalangeal and carpometacarpal joints
Extensor pollicis longus	Posterior surface of the ulna and interosseous membrane	Base of the distal phalanx of the thumb	Posterior interosseous	Extends the thumb at the interphalangeal, metacarpophalangeal and carpophalangeal joints
Extensor indicis	Posterior surface of the ulna and interosseous membrane	Extensor expansion of the index finger	Posterior interosseous	Extends the index finger at its MP and IP joints
Extensor digitorum	Lateral epicondyle of the humerus via the common extensor tendon	Extensor expansions of the index, middle, ring, and little fingers	Posterior inerosseous	Extends the index, middle, ring, and little fingers at their MP and IP joints and extends the hand
Extensor digiti minimi	Lateral epicondyle of the humerus via the commonn extensor tendon	Extensor expansion of the little finger	Posterior interosseous	Extends the little finger at its MP and IP joints

The Hand

Muscle	Origin	Insertion	Nerve Supply	Actions
1st lumbrical	Tendon of flexor digitorum profundus for the index finger	Lateral side of the extensor expansion of the index finger	Median	Flexes the index finger at its MP joint and extends it at its IP joints
2nd lumbrical	Tendon of flexor digitorum profundus for themiddle finger	Lateral side of the extensor expansion of the middle finger	Median	Flexes the middle finger at its MP joint and extends it at its IP joints
3rd lumbrical	Tendons of flexor digitorum profundus for the middle and ring fingers	Lateral side of the extensor expansion of the ring finger	Deep branch of ulnar	Flexes the ring finger at is MP joint and extends it at its IP joints
4th lumbrical	Tendons of flexor digitorum profundus for the ring and little fingers	Lateral side of the extensor expansion of the little finger	Deep branch of ulnar	Flexes the little finger at its MP joint and extends it at its IP joint
1st dorsal interosseous	Adjacent sides of the 1st and 2nd metacarpals	lateral sides of the extensor expansion and the base of the proximal phalanx of the index finger	Deep branch of ulnar	Abducts and flexes the index finger at its MP joint and extends it at its IP joints
2nd dorsal interosseous	adjacent sides of the 2nd and 3rd metacarpals	lateral sides of the extensor expansion and the base of the proximal phalanx of the middle finger	deep branch of ulnar	abducts andflexes the middle finger at its MP joint and extends it at its IP joints
3rd dorsal interosseous	adjacent sides of the 3rd and 4th metacarpals	medial sides of the extensor expansion and the base of the proximal phalanx of the middle finger	deep branch of ulnar	abducts and flexes the middle finger at its MP joint and extends it at its IP joints
4th dorsal interosseous	adjacent sides of the 4th and 5th metacarpals	medial sides of the extensor expansiion and the base of the proximal phalanx of the ring finger	deep branch of ulnar	abducts and flexes the ring finger at its MP joint and extends it at its IP joint
1st palmar interosseous	palmar surface of the 2nd metacarpal	medial side of the extensor expansion of the index finger	deep branch of ulnar	adducts and flexes the index finger at its MP joint and extends it at its IP joint
2nd palmar interosseous	palmar surface of the 4th metacarpal	lateral side of the extensor expansion of the ring finger	deep branch of ulnar	adducts and flexes the ring finger at its MP joint and extends it at its IP joints
3rd palmar interosseous	palmar surface of the 5th metacarpal	lateral side of the extensor expansion of the little finger	deep branch of ulnar	adducts and flexes the little finger at its MP joint and extends it at its IP joints
Abductor pollicis brevis	Flexor retinaculum, scaphoid, and trapezium	lateral side of the base of the proximal phalanx of the thumb	recurrent branch of median	abducts the thumb at its carpometacarpal joint
flexor pollicis brevis	flexor retinaculum and trapezium	lateral side of the base of the proximal phalanx of the thumb	recurrent branch of the median	flexes the thumb at its carpometacarpal and MP joints
Opponens pollicis	flexor retinaculum and trapezium	lateral side of the 1st metacarpal	recurrent branch of median	flexes and medially rotates the thumb at its carpometacarpal joint
adductor pollicis	transverse head from the palmar surface of the shaft of the 3rd metacarpal and oblique head from capitate and the bases of the 2nd and 3rd metacarpals	medial side of the base of the proximal phalanx of the thumb	deep branch of ulnar	adducts the thumb at itscarpometacarpal joint and flexes the thumb at its MP joint
Abductor digiti minimi	pisiform	medial side of the base of the proximal phalanx of the little finger	deep branch of ulnar	abducts the little finger at its MP joint
flexor digiti minimi	flexor retinaculum and hook of the hamate	medial side of the base of the proximal phalanx of the little finger	deep branch of the ulnar	flexes the little finger at its MP joint
opponens digiti minimi	flexor retinaculumm and hook of the hamate	medial side of the 5th metacarpal	deep branch of the ulnar	flexes and laterally rotates the 5th metacarpal at its carpometacarpal joint
palmaris brevis	flexor retinaculum and medial border of the palmar aponeurosis	dermis on the medial bord

Buttock Muscles

Muscle	Origin	Insertion	Nerve Supply	Action
gluteus maximus	external surface of the wing of the ilium posterior to the posterior gluteal line, posteror surfaces of the sacrum and coccyx, and sacrotuberous ligament	most fibers insert into the iliotibial tract of the fascia lata; the remainder insert ontl gluteal tuberosity	inferior gluteal	extends the trunk of the body relative to the thigh when rising from a seated position; extends the thigh
gluteus medius	external surface of the ilium between the posterior and anterior gluteal lines	lateral aspect of the greater trochanter of the femur	superior gluteal	abducts and internally rotates the thigh
gluteus minimus	external surface of the ilium between the anterior and inferior gluteal lines	anterior aspect of the greater trochanter of the femur	superior gluteal	abducts and internally rotates the thigh
tensor fasciae latae	anterior superior iliac spine, anterior part of the outer surface of the iliac crest, and deep surface of the uppermost part of the iliotibial tract	iliotibial tract of the fascia lata	superior gluteal	tenses the iliotibial tract; abducts, internally rotates, and flexes the thigh
piriformis	anterior surface of the sacrum	greater trochanter of the femur	branches from the anterior rami of S1 and S2	externally rotates the thigh
superior gemellus	ischial spine	greater trochanter of the femur	nerve to obturator internes	externally rotates the thigh
obturator internus	pelvic surface of the obturator membrane and the surrounding bony margin	greater trochanter of the femur	nerve to obturator internus	externally rotates the thigh
inferior gemellus	ischial tuberosity	greater trochanter of the femur	nerve to quadratus femoris	externally rotates the thigh
quadratus femoris	ischial tuberosity	quadrate tubercle of the femur	nerve to quadratus femoris	externally rotates the thigh

Sacral Plexus

Nerve	Muscles	Major joints
Superior gluteal	gluteus medius gluteus minimus tensor fasciae latae	sacroiliac hip
inferior gluteal	gluteus maximus
nerve to obturator internus	superior gemellus obturator internus
nerve to quadratus femoris	inferior gemellus	quadratus femoris
common peroneal	biceps femoris--short tibialis anterior extensor hallucis longus extensor digitorum longus peroneus tertius extensor digitorum brevis peroneus longus peroneus brevis	knee proximal tibiofibular distal tibiofibular ankle
tibial	semimembranosus semitendinosus biceps femoris--long head gastrocnemius soleus plantaris popliteus tibiallis posterior flexor hallucis longus flexor digitorum longus abductor hallucis flexor hallucis brevis adductor hallucis flexor digitorum brevis quadratus plantae lumbricals of the foot interossei of foot--plantsr/dorsal abductor digiti minimi flexor digiti minimi brevis	knee proximal tibiofibular distal tibiofibular ankle

Posterior/Medial/Anterior Muscles of Thigh

Semimembranosus	ischial tuberosity	posterior aspect of the medial tibial condyle	tibial portion of sciatic	extends the thigh and flexes and internally rotates the leg
semitendinosus	ischial tuberosity	upper part of the medial surface of the tibia	tibial portion of the sciatic	extends the thigh and flexes and internally rotates the leg
biceps femoris	long head from the ischial tuberosity; short head from the lateral edge of the linea aspera, lateral supracondylar line, and lateral inermuscular septum	head of the fibula	tibial portion of the sciatic for long head; common peroneal portion of the sciatic for short head	long head extends the thigh; short heads flex and externally rotate the leg
adductor magnus	adductor part from the inferior ramus of the pubis and ramus of the ischium; hamstring part from the ischial tuberosity	adductor part onto gluteal tuberosity; linea aspera, and upper part of the medial supracondylar line; hamstring part onto adductor tubercle	obturator for the adductor part and tibial portion of the sciatic for the hamstring part	adductor part adducts the thigh and hamstring part extends the thigh
gracilis	body and inferior ramus of the pubis and ramus of the ischim	upper part of the medial surface of the tibia	obturator	adducts the thigh and internally rotates the leg
adductor brevis	body and inferior ramus of the pubis	upper part of the linea aspera	obturator	adducts the thigh
obturator externus	outer surface of the obturator membrane and its bony margin	trochanteric fossa of the femur	obturator	externally rotates the thigh
adductor longus	body of the pubis	middle part of the linea aspera	obturator	adducts the thigh
Pectineus	pecten pubis	pectineal line of the femur	femoral and obturator	flexes and adducts the thigh
iliacus	iliac fossa and upper lateral part of the sacrum	insertion tendon of psoas major and lesser trochanter of the femur	femoral	flexes the thigh
psoas major	bodies and transverse processes of the 12th thoracic and five lumbar vertebrae and the intervertebral discs between them	lesser trochanter of the femur	branches of the anterior rami of L1, L2, L3	flexes the thigh
sartorius	anterior superior iliac spine	upper part of the medial surface of the tibia	femoral	abducts, flexes, and externally rotates the thigh and flexes and internally rotates the leg
rectus femoris	straight head from the anterior inferior iliac spine; reflected head from a groove above the acetabulum	tibial tuberosity via the patellar legament	femoral	flexes the thigh and extends the leg
vastus medialis	medial edge of the linea aspera and the medial intermuscular septum	tibial tuberosity via the patellar ligament	femoral	extends the leg
vastus intermedius	anterior and lateral surfaces of the femoral shaft	tibial tuberosity via the patellar legament	femoral	extends the leg
vastus lateralis	greater trochanter of teh femur and the lateral edge of the linea aspera	tibial tuberosity via the patellar ligament	femoral	extends the leg

Muscles of the Leg

Muscle	Origin	Insertion	Nerve supply	Action
Tibialis anterior	lateral tibial condyle, upper half of the lateral surface of the tibia, and adjoining part of the anterior surface of the interosseous membrane	medial cuneiform and base of the 1st metatarsal	deep peroneal	dorsiflexes and inverts the foot
extensor hallucis longus	middle two-fourths of thw medial surface of the fibula and adjoining part of the anterior surface of the interosseous membrane	base of the distal phalanx of the big toe	deep peroneal	extends the big toe and dorsiflexes the foot
extensor digitorum longus	lateral tibial condyle, upper three-fourths of the medial surface of the fibula, and upper part of the anterior surface of the interosseous membrane	extensor expansions of the lateral four toes	deep peroneal	extends the lateral four toes and dorsiflexes the foot
peroneus tertius	lower third of the medial surface of the fibula and adjoining part of the anterior surface of the interosseous membrane	base of the 5th metatarsal	dee peroneal	dorsiflexes and everts the foot
peroneus longus	upper two-thirds of the lateral surface of the fibula	medial cuneiform and base of the 1st metatarsal	superficial peroneal	everts and plantarflexes the foot
peroneus brevis	lower two-thirds of the lateral surface of the fibula	base of the 5th metatarsal	superficial peroneal	everts and plantarflexes the foot
gastrocnemius	medial head from the popliteal surface of the femur and the upper posterior part of the medial tibial condyle; lateral head from the lateral surface of the lateral femoral condyle	posterior surface of the calcaneus	tibial	plantarflexes the foot and flexes the leg
soleus	posterior surface of the head and upper one-fourth of the shaft of the fibula, soleal line of the tibia, and the oblique popliteal ligament	posterior surface of the calcaneus	tibial	plantarflexes the foot
plantaris	lower end of the lateral supracondylar line of the femur and the oblique popliteal ligament	posterior surface of the calcaneus	tibial	weakly plantarflexes the foot and weakly flexes the leg
popliteus	lateral surface of the lateral tibial condyle and the lateral meniscus	upper posterior surface of the tibia	tibial	internally rotates the leg (non-weight-bearing) and flexes the leg
tibialis posterior	medregions of the posterior surfaces of the shafts of the tibia and fibula and the posterior surface of the intervening interosseous membrane	tuberosity of the navicular, medial cuneiform, cuboid, sustenaculum tali, and the bases of the 2nd, 3rd, and 4th metatarsals	tibial	inverts and plantarflexes the foot
flexor hallucis longus	lower two-thirds of the posterior surface of the shaft of the fibula and the lower part of the posterior surface of the interosseous membrane	base of the distal phalanx of the big toe	tibial	flexes the big toe at its metatarsophalangeal and interphalangeal joints and plantarflexes the foot
flexor digitorum longus	posteromedial surface of the tibia below the soleal line	bases of the distal phalanges of the lateral four toes	tibial	flexes the lateral flur toes and plantarflexes the foot