extremities muscles

Pectoralis major

O-sternal end of clavicle

I- greater tubercle of humerus

A-adducts and medially rotates arm

Nerve Supple-lateral and medial pectoral nerve

Deltoid

O-spine of scapula

I-deltoid tuberosity of humerus

A-prime mover of arm abduction

NS- axillary nerve

Latissimus Doris

O-indirect attachment via lumbodorsal fascia into spines of lower six thoracic vertebrae, lumbar vertebrae, lower 3 to 4 ribs, and iliac crest

I- spirals around teres major to insert in floor of intertubercular sulcus of humerus.

A- prime mover of the arm extension, arm adductor, medially rotates arm

NS- thoracodorsal nerve

Subscapularis

O- subscapular fossa of scapula

I-lesser tubercle of humerus

A- rotates arm medially

NS- Subscapular nerves

Supraspinatus

O- supraspinous fossa of scapula

I- superior part of the greater tubercle of the humerus

A- initiates abduction of the arm

NS- suprascapular nerve

Infraspinatus

O- infraspinous fossa of scapula

I- greater tubercle of humerus posterior to insertion of supraspinatus

A- rotates arm laterally

NS- Suprascapular nerve

Teres minor

O- lateral border of dorsal scapular surface

I-greater tubercle of humerus inferior to infraspinatus insertion

A- rotates arm laterally

NS- axillary nerve

Teres Major

O-posterior surface of scapula at inferior angle

I-crest of lesser tubercle on anterior humerus; insertion tendon fused with that of latissimus doris

A- extends, medially rotates, and adducts arm

NS- lower subscapular nerve

Coracobrachialis

O- Coracoid process of scapula

I- medial surface of humerus shaft

A- flexes and adducts arm

NS- Musculocutaneous nerve

Triceps brachial

O- long head; infraglenoid tubercle of scapula; lateral head: posterior shaft of humerus; medial head: posterior humeral shaft distal to radial groove

I- by common tendon into olecranon of ulna

A- forearm extensor

NS- radial nerve

Anconeus

O- lateral epicondyle of humerus

I- lateral aspect of olecranon of ulna

A- elbow extension, also helps abduct ulna

NS- Radial nerve

Biceps brachii

O- short head: coracoid process; long head: supraglenoid tubercle and lip of glenoid cavity; tendon of long head runs within shoulder joint capsule and into intertubercular sulcus of humerus

I- by common tendon into radial tuberosity

A- Flexes and supinates forearm

NS- Musculocutaneous nerve

Brachioradialis

O-lateral supracondylar ridge at distal end of humerus

I-base of radial styloid process

Synergist in flexing forearm

Radial nerve

Pronator teres

O-medial epicondyle of humerus; coronoid process of ulna

I-by common tendon into lateral radius, midshaft

A: Pronates forearm

NS: Median nerve

Flexor carpi radialis

O- medial epicondyle of humerus

I-base of second and third metacarpals;

insertion tendon easily seen and provides guide to position of radial artery at wrist (used for taking pulse)

A- Powerful flexor of hand

NS- Median nerve

Palmaris longus

o—medial epicondyle of humerus

I-fascia of palm (palmar aponeurosis

A- Tenses skin and fascia of palm during hand movements

NS- Median nerve

Flexor carpi ulnaris

o—medial epicondyle of humerus; olecranon and posterior surface of ulna

I-pisiform and hamate bones and base of fifth metacarpal

A-Powerful flexor and adductor of hand

NS: Ulnar nerve

Flexor digitorum superficialis

O—medial epicondyle of humerus, coronoid process of ulna; shaft of radius

I-by four tendons into middle phalanges of second to fifth fingers

A: Flexes hand and middle phalanges of second to fifth fingers

Ns: Median nerve

Flexor pollicis longus

O-anterior surface of radius and interosseous membrane

I-distal phalanx of thumb

A: Flexes distal phalanx of thumb

NS: Branch of median nerve

Flexor digitorum profundus

O-coronoid process, anteromedial surface of ulna, and interosseous membrane

I-by four tendons into distal phalanges of second to fifth fingers

A:Flexes distal interphalangeal joints

NS: Medial half by ulnar nerve; lateral half by median nerve

Pronator quadratus

O- distal portion of anterior ulnar shaft

I- distal surface of anterior radius

A: Prime mover of forearm pronation

NS: median nerve

(Green)

Extensor carpi radialis longus

I-base of second metacarpal

O-lateral supracondylar ridge of humerus

Extends and abducts hand

Radial nerve

Extensor carpi radialis brevis

I-base of third metacarpal

O-lateral epicondyle of humerus

Extends and abducts hands

Deep branch of radial nerve

Extensor digitorum

I-by four tendons into extensor expansions and distal phalanges of second to fifth fingers

O-lateral epicondyle of humerus

A: extension of finger

Posterior interosseous nerve, a branch of radial nerve

Extensor carpi ulnaris

I-base of fifth metacarpal

O-lateral epicondyle of humerus and posterior border of uina

Extends, adducts hand

posterior interosseous nerve

Supinator

I—proximal end of radius

O-lateral epicondyle of humerus; proximal ulna

Supinate forearm

Posterior interosseous nerve

Abductor pollicis longus

O-posterior surface of radius and ulna; interosseous membrane

I—base of first metacarpal and trapezium

Abduct and extends thumb

Posterior interosseous nerve

Extensor pollicis brevis and longus

I-base of proximal (brevis) and distal (longus) phalanx of Thumb

O-dorsal shaft of radius and ulna; interosseous membrane

Extends thumb

Posterior interosseous nerve

Extensor indicis

O-posterior surface of distal ulna; interosseous membrane

I-extensor expansion of index finger; joins tendon of extensor

ACTION: Extends index finger (digit Il) and assists in extending wrist

NERVE SUPPLY: Posterior interosseous nerve

liopsoas:

Illiacus and psoas major

Iliacus

O-iliac fossa and crest, ala of sacrum I-lesser trochanter of femur via iliopsoas tendon

flexing thigh, or for flexing trunk on thigh

Femoral nerve

Psoas major

O—by fleshy slips from transverse processes, bodies, and discs of lumbar vertebrae and T12 I-esser trochanter of femur via iliopsoas tendon

Flexes vertebral column laterally

Ventral rami

Sartorius

O-anterior superior iliac spine I-winds around medial aspect of knee and inserts into medial aspect of proximal tibia

Flexes, abducts, and laterally rotates thigh;

Femoral nerve

Adductor magnus

O—ischial and pubic rami

composite muscle that is

and ischial tuberosity

I—linea aspera and part adductor and part adductor tubercle of femur

A: adducts and medially rotates and flexes thigh; thigh extension

NS: Obturator nerve and sciatic nerve

Adductor longus

O- pubis near pubic symphysis

I: linea aspera

A: adducts, flexes, and medially rotates thigh

NS: obturator nerve

Adductor brevis

O—body and inferior pubic ramus

I—linea aspera above adductor longus

A:Adducts, flexes, and medially rotates thigh

NS: Obturator nerve

Pectineus

O—pubis (and superior ramus

I-from lesser trochanter inferior to the linea aspera on posterior aspect of femur

A: Adducts, flexes, and medially rotates thigh

NS: Femoral and sometimes obturator nerve

Gracilis

O-inferior ramus and body of pubis and adjacent ischial ramus

I-medial surface of tibia just inferior to its medial condyle

A:Adducts thigh, flexes and medially rotates leg,

NS:obturator nerve

Rectus femoris

O- anterior inferior iliac spine and superior margin of acetabulum

I: patella and tibial tuberosity via patellar ligament

A: extends leg and flexes thigh at hip

NS: femoral nerve

Vastus lateralis

O-greater trochanter, Intertrochanter, intertrochanteric line, linea aspera

I: patella and tibial tuberosity via patellar ligament

A: Extends leg and stabilizes knee

NS: femoral nerve

Vastus medialis

O-linea aspera, intertrochanteric and medial supracondylar lines

I-patella and tibial tuberosity via patellar ligament

A: Extends leg

NS: Femoral nerve

Vastus intermedius

O- anterior and lateral surface of proximal femur shaft

I-patella and tibial tuberosity via patellar ligament

A: extends leg

NS: femoral nerve

Tensor fascia lata

O-anterior aspect of iliac crest and anterior superior iliac spine

I-iliotibial tract*

A: Steadies the leg and trunk on thigh by tightening iliotibial tract

NS:Superior gluteal nerve (Ly and Ls)

Gluteus maximus

o-dorsal ilium, sacrum, and coccyx

I-gluteal tuberosity of femur; iliotibial tract

A:Major extensor of thigh

NS: Inferior gluteal nerve

Gluteus medius

O-between anterior and posterior gluteal lines on lateral surface of ilium

I-by short tendon into lateral aspect of greater trochanter of femur

A: Abducts and medially rotates thigh;

NS: Superior gluteal nerve

Gluteus minimus

O-between anterior and inferior gluteal lines on external surface of ilium

I-anterior border of greater trochanter of femur

A: Abducts and medially rotates thigh;

NS: Superior gluteal nerve

Piriformis

O-anterolateral surface of sacrum (opposite greater sciatic notch)

I-superior border of greater trochanter of femur

A:Rotates extended thigh laterally;

NS:S, and S2, Ls

Obturator externus

O-outer surfaces of obturator membrane, pubis, and ischium, margins of obturator foramen

I-by a tendon into trochanteric fossa of posterior femur

A: Rotates extended thigh laterally;

NS:Obturator nerve

Obturator internus

O-inner surface of obturator membrane, greater sciatic notch, and margins of obturator foramen

I-greater trochanter in front of piriformis

A:Rotates extended thigh laterally;

L5 and S,

Gemellus

O— ischial spine (superior); ischial tuberosity (inferior)

I-greater trochanter of femur

A:Rotates extended thigh laterally;

NS: Ls and S,

Quadratus femoris

O—ischial tuberosity

I-intertrochanteric crest of femur

A: Rotates thigh laterally and stabilizes hip joint

L5 and S1

Biceps femoris

I--common tendon passes downward and laterally (forming lateral border of popliteal fossa) to insert into head of fibula and lateral condyle of tibia

O— ischial tuberosity (long head); linea aspera, lateral supracondylar lines, distal femur (short head)

A:Extends thigh and flexes

NS: Sciatic nerve tibial nerve to long head, common fibular nerve to short head

Semitendinosus

O—ischial tuberosity in common with long head of biceps femoris

I-medial aspect of upper tibial shaft

A: Extends thigh and flexes leg;

NS: Sciatic nerve-tibial nerve portion

Semimembranosus

O-ischial tuberosity

L—medial condyle of tibia; via oblique popliteal ligament to lateral condyle of femu

Action: Extends thigh and flexes leg

NS: Sciatic nerve tibial nerve portion

Tibialis anterior

O-lateral condyle and upper 2/3 of tibial shaft;interosseous membrane

I-by tendon into inferior surface of medial cuneiform and first metatarsal bone

A: inverts foot, dorsiflexion

NS: Deep fibular nerve

Extensor digitorum longus

O-lateral condyle of tibia; proximal 3/4 of fibula; interosseous membrane

I-middle and distal phalanges of second to fifth toes via extensor expansion

A: extensor of toe

NS: Deep fibular nerve

Fibularis (peroneus) tertius

O-distal anterior surface of fibula and interosseous membrane

I-tendon inserts on dorsum of fifth metatarsal

Action: Dorsiflexes and everts foot

NS: Deep fibular nerve (Ls and S,)

Extensor hallucis longus

O-anteromedial fibula shaft and interosseous membrane

I-tendon inserts on distal phalanx of great toe

A: Extends great toe; dorsiflexes foot

NS: Deep fibular nerve (Ls and S,)