Flexor carpi ulnaris muscle
|Flexor carpi ulnaris|
|Dorsal (left) and ventral (right) views of deep muscles of the forearm. FCU is visible in blue.|
|Latin||musculus flexor carpi ulnaris|
|Gray's||subject #125 447|
|Origin:||medial epicondyle (common flexor tendon)|
|Nerve:||muscular branches of ulnar nerve|
|Action:||flexion of wrist|
|Antagonist:||Extensor carpi ulnaris muscle|
The flexor carpi ulnaris muscle (FCU) is a muscle of the human forearm that acts to flex and adduct the hand.
Origin and insertion
- The humeral head arises from the medial epicondyle of the humerus by the common flexor tendon.
- The ulnar head arises from the medial margin of the olecranon of the ulna and from the upper two-thirds of the dorsal border of the ulna by an aponeurosis.
The tendon of flexor carpi ulnaris can be seen on the anterior of the distal forearm. On a person's distal forearm, right before the wrist, they will see either two or three tendons. Flexor carpi ulnaris is the most medial (closest to the little finger) of these. (The most lateral one is flexor carpi radialis muscle, and the middle one, if it exists, is palmaris longus.)