Kinesiology PED 2440

Muscles KEY POINTS: Pictures of the wrist and hand muscles Muscles only PULL on bones Muscles only act on those joints which they cross A muscle (usually) can not cause an opposite action (e.g. flexion and extension) Origin = stable end; closer to the body Insertion = movable end; further from the body Pictures of the wrist and hand muscles Look to the name of the muscle for help

Flexor Carpi Radialis Palmar surface Origin: Insertion: Actions: medial condyle of the humerus Insertion: base of the 2nd and 3rd metacapals (palmar surface) Actions: flexion of the wrist abduction of the wrist flexion of the elbow

Flexor Carpi Ulnaris Palmar Origin: Insertion: Actions: medial condyle of the humerus Insertion: pisiform, base of the 5th metacarpal Actions: flexion of the wrist adduction of the wrist flexion of the elbow

Palmaris Palmar Origin: Insertion: Action: Medial epicondyle Palmar aponeurosis of 2-5 metacarapls Action: flexion of the wrist weak flexion of the elbow

Flexor Digitorum Superficialis Palmar Origin: medial condyle of the humerus ulnar head - medial coronoid area radial head - radial tuberosity area Insertion: split tendons attach to the sides of the middle phalanx of the four fingers Actions: flexion of fingers, wrist and the elbow (weak)

Flexor Digitorum Profundus • Palmar • Origin: – Upper, medial surface of the ulna • Insertion: – split tendons attach to distal phalanx of the four fingers • Actions: – flexion fingers and wrist

Flexor Pollicus Longus Palmar Origin: middle anterior surface of the radius Insertion: base of the distal phalanx of the thumb (palmar surface) Actions: flexion of wrist and thumb

Extensor Carpi Radialis Longus Dorsal Origin: lateral condyle of the humerus Insertion: base of the 2nd metacarpal Actions: Extension of the wrist; Abduction Weak extension of the elbow NOTE: Extensor Carpi Radialis Brevis will not be covered

Extensor Carpi Ulnaris Dorsal Origin: lateral epicondyle of the humerus Insertion: base of the 5th metacarpal Actions: Extension of the wrist Adduction of the wrist Weak extension of the elbow

Extensor Digitorum Dorsal Origin: Insertion: Actions: lateral epicondyle of the humerus Insertion: middle and distal phalanges of the four fingers Actions: Extension of the fingers Extension of the wrist Weak extension of the elbow

Extensor Indicis • Dorsal • Origin: • Insertion: • Actions: – Distal, posterior ulna • Insertion: – middle and distal phalanxes of the second phalange • Actions: – Extension of the 2nd finger – Weak wrist extension

Extensor Digiti Minimi • Dorsal • Origin: – Lateral epicondyle of the humerus • Insertion: – Base of the middle and distal phalanxes of the 5th phalange • Actions: – Extension of the 5th finger – Weak wrist extension

Extensor Pollicis Longus Dorsal Origin: posterior lateral surface of the distal ulna Insertion: base of the last phalanx of the thumb (dorsal side) Actions: Extension of the wrist Extension of the thumb NOTE: The extensor pollicus brevis and the abductor pollicus will not be covered.

Summary Table 7.1 except for the Extensor Carpi Radialis Brevis, Extensor Pollicus Brevis, and Abductor Pollicus Longus Quiz Bones Joints and their Actions Muscles Location Actions Other info

Flexion Besides their actions, what do they have in common? Flexor carpi radialis Flexor carpi ulnaris Flexor digitorum superficialis Flexor digitorum profundus Flexor pollicus Palmaris longus

Extension Besides their actions, what do they have in common? Extensor carpi radialis Extensor carpi ulnari Extensor digitorum Extensor digiti minimi Extensor indicis Extensor pollicus longus

Radial Flexion (Abduction) Besides their actions, what do they have in common? Ext. carpi radialis Flexor carpi radialis Abductor pollicis (ext. pollicis longus and brevis)

Ulnar Flexion (Adduction) Besides their actions, what do they have in common? Extensor carpi ulnaris Flexor carpi ulnaris

Thumb Actions Flexor pollicis longus Extensor pollicis longus and brevis

Nerves and Arteries

Nerves (p. 140, 141) Median Ulnar Radial Anterior and later muscles of the forearm and radial side of hand Ulnar Anterior and medial forearm and ulnar side of hand Radial Posterior forearm. No hand muscles Arteries Radial - anterior

Arteries Radial – anterior at wrist and posterior to the hand Ulnar - anterior