The extensor carpus ulnar muscle is a superficial muscle of the posterior region of the forearm, placed medially in relation to the extensor muscle proper to the little finger.
It has a common origin with this muscle and with the common extensor finger muscle (posterior epicondyle of the humerus and antibrachial fascia). It also originates from the posterior margin of the ulna and from the articulation of the elbow.
Its bundles are directed obliquely towards the medial inferior margin of the forearm and continue with a tendon that crosses the sixth dorsal ligament of the carpus and reaches the base of the 5th metacarpal bone.
With his contraction he extends and adduces the hand. Despite the name, the main action of the muscle is the adduction of the hand, its antagonist is the long abductor muscle of the thumb.
It is innervated by the radial and deep radial nerve (C7-C8). It is sprayed from the ulnar artery.
| ORIGIN E lateral humerus of the humerus thanks to the common extensor tendon, posterior margin of the ulna through an aponeurosis and antibrachial fascia |
| INSERTION Base of the fifth metacarpal |
| ACTION Extend and adduce the wrist |
| INNERVATION Deep radial and radial nerve (C7-C8) |
| Upper limb | Lower limb | Trunk | Abdomen | Articles |
