Palmar interosseous muscles

Palmar interosseous muscles , mm. Interossei palmares, represent three spindle-shaped muscular bundles located in the interosseous spaces of the pastern, the first interosseous muscle lies on the radial half of the palm and, beginning on the ulnar side of the second metacarpal bone, is attached to the ulnar side of the metacarpal phalangeal joint of the index finger and weaves into its posterior aponeurosis . The second and third interosseous muscles are located on the ulnar half of the palm and, starting on the radial side of the IV and V metacarpal bones, attach to the radial side of the capsules of the metacarpophalangeal joints of the ring finger and little finger.

Function: bend the proximal phalanges and straighten the middle and distal phalanges of the index and ring fingers and little finger, bring these fingers to the middle finger.

Innervation: n. Ulnaris (CVIII-ThI).

Blood supply: arcus palmaris profundus.