muscles

Student Name
Instructor
Course Title
Date due:
Origin, Insertion, Action, and Innervation of Muscles
Muscle
Name Origin Insertion Action Innervation
Rectus Abdominas Pubic crest, Pubic sympysis; occur around the pelvic bone Costal cartilage (5th, 6th, 7th ribs), Xiphloid process of the sternum.
Causes rib cage and
Pelvis to lean into the middle of the abdomen. Lower six thoraco-abdominal nerves
Erector Spinae Sacrum, ilium, thoracic vertebrae, ribs Thoracic and cervical vertebrae, ribs, skull Extension of neck and trunk, rotation of head, maintaining body posture Dorsal Rami of cervical, thoracic, and lumbar spinal nerves
Pectoralis Major Clavicle head-medial half, Sternal head- outer sternum, upper six coastal cartilages. Lateral lip of the bicipital groove of the humerus and deltoid tuberosity Shoulder flexion, internal rotation and adduction of the humerus, draw scapula anteriorly and inferiorly. Medial and lateral pectoral nerve
Serratus Anterior Lateral superior eight ribs, anterior intercostal membrane, lower four slips adjacent to the abdominal oblique Costal aspect of the medial border of the scapula Upward rotation and protraction of the scapula. Long thoracic nerve (C5, 6, 7)
Rhomboid Major Spinous process of the (T2-T5) vertebrae. Scapula Rotates retracts and moves scapula to the thoracic wall. Dorsal scapular nerve
Rhomboid minor Nuchal ligament (C7-T1) Scapula Rotates, retracts and fix scapula to the body wall Dorsal scapular nerve
Latissimus Dorsi
Spinous process (T7-T12), Inferior ribs, thoracolumbar fascia, iliac crest Intertubercular groove of the humerus Extension and rotation of the arm, adduction, medial rotation of the humerus.

Thoracodorsal nerve
Trapezius The medial third of the superior nuchal line, external occipital protuberance, nuchal ligament, and spinous process C7-T12. Lateral 1/3 of the clavicle acromion, and spine of scapula Descending part-elevates pectoral girdle. Middle part- retracts scapula. Ascending part- depresses shoulders.
Descending and ascending combined- rotate scapula upwards. Spinal root of accessory nerve (CN 11) and cervical nerve (C3 and C4)
Teres Major Posterior aspect of the inferior angle of the scapula Medial lip of the intertubercular sulcus of the humerusConducts medial rotation of the humerus, depress shoulder, protracts the scapula Lower subscapular (C5, 6)
Palmaris Longus
Medial epicondyle through the common flexor tendon Central portion of the flexor retinaculum, superficial section of palmar aponeurosis Facilitates flexion of the wrist Ventral primary rami of T7-T12
Flexor Carpi Ulnaris
Medial epicondyle via the common flexor tendon Pisiform, hamate bones, and the fifth metacarpal Flexion and adduction of the wrist. Facilitates flexion of the arm C8, T1 of the Ulna nerve
Flexor Carpi Radialis
Medial epicondyle of the humerus Base of the 2nd and in some people the 3rd metacarpal Flexion of the wrist Median nerve (C6, 7)
Flexor Digitorum superficialis
Medial epicondyle, coronoid process, radius Sides of the middle-phalanx (2-5) Flexion of the MCP and PIP joints Median nerve
Flexor digitorum profundus
Anterior Portion of the Ulna Base of distal phalanx Flexor of MCP, PIP and DIP joints Median nerve and Ulna nerve
Flexor Pollus Lungus
Anterior surface of the radius, and adjacent interosseous membrane Base of the distal phalanx of the thumb Flexes the interphalangeal and metacarpophalangeal joints of the thumb Median nerve (Anterior interosseous branch)
Extensor Carpi radialis
Lower 1/3 of the lateral supracondyl ridge of humerus, lateral intermuscular septum. ECRB originates from the lateral epicondyle Posterior base of the 2nd metacarpal and III metacarpal Extension and abduction of hand at the wrist Radial nerve (C6,7)
Extensor Carpi Ulnaris
Lateral epicondyle of the humerus Attached to the base of metacarpal V Extends and abducts the wrist Radial nerve; deep branch
Extensor Indicis
Lower posterior shaft of the ulna next to the interosseous membrane Extensor expansion of ulna Extends all joints of the index finger Posterior interosseous nerve (C7, 8)
Extensor Digitorium CommunisCommon extensor located at the anterior aspect of the lateral epicondyle of the humerus Extensor expansion via the middle and distal phalanges by four tendons Extension of the joints of the finger Posterior interosseous nerve (C7, 8)
Extensor Digiti MinimiLateral epicondyle of the humerus Extensor expansion of the 5th digit Extends 5th digit at the metacarpophalangeal and interphalangeal joints Posterior interosseous nerve (C7,8)
Extensor Pollicis Longus Posterior surface of the upper 1/3 of the Ulna and interosseous membrane Base of distal phalanx of the thumb Extends distal phalanx at carpometacarpal and interphalangeal joints Posterior interosseous nerve; deep branch of the radial nerve
Extensor pollicis Brevis
Lower 1/3 of the shaft of the radius, and adjacent interosseous membrane On the tendons of the radial extensors and brachioradialis to base of proximal phalanx of the thumb Extends metacarpophalangeal joint of the thumb Posterior interosseous nerve (C7,8)
Pronator teres
Medial epicondyle and coronoid process of the ulna. Attaches in a lateral angle to the mid-shaft of the radius Pronation of the forearm Median nerve
Pronator quadratus Distal quarter of the anterior surface of ulna Distal quarter of the anterior surface of ulna Pronation of the forearm by binding of the radius and ulna through the deep fiber Anterior interosseous nerve (C8 and T1)
APL Abductor pollicis Lungus Upper posterior surface of ulna and middle 1/3 of the interosseous membrane Over tendons of radial extensors and brachioradialis to the base of 1st metacarpal and trapezium Abducts and extends thumb at the carpometacarpal joint Posterior interosseous nerve