Action.

Muscle.

Origin.

Insertion.

Nerve-supply.

Flexion

Flexor carpi radialis

From common tendon on inner condyle of humerus and deep fascia

Palmar surfaces of base of second metacarpal bone and a small slip to third metacarpal

Median

Palmaris longus

From common tendon and deep fascia

Surface of anterior annular ligament and central part of palmar fascia

Median

Flexor carpi ulnaris

From common tendon on inner condyle and deep fascia, the inner border of the olecranon process, and the upper three-fifths of the posterior border of the ulna

To the pisiform bone, and continued on to the hook of the unciform and the base of the fifth metatarsal

Ulnar

Flexor sublimis digitorum

From the common flexor tendon ; the internal lateral ligament of the elbow-joint and deep fascia; the inner border of coronoid process of ulna (above that of pronator radii teres); the oblique line of the radius

The muscle divides into four tendons; these split to allow the tendon of flexor profundus digitorum to pass through, and, after uniting again, each tendon divides into two parts to be inserted into the sides of the second phalanges of the four inner metatarsals

Median

Flexor profundus digitorum

From the upper two-thirds of the anterior and internal surfaces of the ulna up to the inner surface of the olecranon process; inner half of middle third of the interosseous membrane and deep fascia

The muscle divides into four tendons, each of which passes through the corresponding tendon of flexor sublimis digitorum to be inserted in the bases of the terminal phalanges of the four inner metatarsals (see Lum-bricales)

Ulnar and anterior interosseous

(median)

Flexion (contd.)

Flexor longus pollicis

From the middle half of the anterior surface of the shaft of the radius and the corresponding half of the interosseous membrane

The palmar surface of the base of the terminal phalanx of the thumb

Anterior interosseous

Extension

Extensor carpi radialis longior

From the ventral surface of the lower third of the outer supra-condyloid ridge of the humerus, the intermuscular septum, and the common extensor tendon on the outer condyle

The dorsal surface of the base of the second metacarpal bone

Musculo-spiral

Extensor carpi radialis brevior

From the common extensor tendon, the external lateral ligament of the elbow-joint and deep fascia

The dorsal surface of the base of the third metacarpal bone

Posterior interosseous

Extensor communis digitorum

From the common extensor tendon and deep fascia

The muscle divides into four tendons, to be inserted in the four inner digits. Each one passes down the back of the hand and spreads out over the knuckle; it then divides into three slips-the middle one is inserted into the base of the second phalanx, and the side ones join together to be inserted into the base of the terminal phalanx

Posterior interosseous

Extensor minimi digiti

From the common extensor tendon and deep fascia

Into the expansion of the extensor tendon Oil the back of the first phalanx of the little linger

Posterior interosseous

Extensor carpi ulnaris

From the common tendon and i deep fascia and middle half of the posterior border of the ulna

The ulnar side of the base of the fifth metacarpal bone

Posterior interosseous

Extensor ossis metacarpi pollicis

From the upper half of the outer surface of the ulna; the middle third of the dorsal surface of the radius and interosseous membrane

The radial side of the base of the first metacarpal

Posterior interosseous

Extension (ronki.)

Extensor brevis pollicis

From the dorsal surface of the radius below extensor ossis meta-carpi pollicis and the interosseous membrane

The dorsal surface of the base of the first phalanx of the thumb

Posterior interosseus

Extensor . longus pollicis

From the middle third of the dorsal surface of the ulna and the interosseous m e m-brane below extensor ossis metacarpi pollicis

The dorsal surface of the base of the second phalanx of the thumb

Posterior interosseous

Extensor indicis

From the dorsal surface of the ulna below extensor longus pollicis and from the interosseous membrane

• The expansion of the tendon of extensor communis digitorum on the first finger

Posterior interosseous

Abduction

Flexor carpi radialis

See Flexion

Extensors carpi radialis longior and brevior

See Extension

Extensors of thumb

See Extension

Adduction

Flexor carpi ulnaris

See Flexion

Extensor carpi ulnaris

See Extension