A Detailed Medial View of the Male Flexor Carpi Ulnaris Muscle

Description

Running along the medial (ulnar) border of the anterior forearm, the flexor carpi ulnaris (FCU) is shown from a medial perspective with its muscular belly arising proximally near the medial epicondyle of the humerus and the olecranon and posterior border of the ulna. Distally, its tendon courses superficial and ulnar toward the wrist, heading for insertion on the pisiform with continuity to the hook of hamate and base of the fifth metacarpal via the pisohamate and pisometacarpal ligaments. The ulnar nerve is logically positioned deep to FCU in the proximal forearm after passing posterior to the medial epicondyle, while the ulnar artery typically lies anterior and radial to the nerve as both descend toward Guyon canal. Medial exposure makes FCU a practical landmark when teaching the cubital tunnel and proximal ulnar neuropathy: after the nerve passes behind the medial epicondyle, it enters the forearm between the humeral and ulnar heads of FCU, a frequent site of compression. This relationship also matters during medial elbow approaches and during evaluation of medial epicondylitis patterns, where FCU origin tenderness can accompany pain with resisted wrist flexion and ulnar deviation. Clear tendon tracking at the ulnar wrist helps differentiate distal ulnar-sided pain sources, including pisotriquetral irritation and ulnar nerve entrapment at Guyon canal. Use this asset for upper-limb anatomy labs, kinesiology modules on wrist flexion and ulnar deviation, and surgical education materials covering cubital tunnel decompression or ulnar nerve transposition planning. It also fits textbook figures on forearm flexor compartments and clinical handouts on ulnar-sided wrist symptoms. Anatomical accuracy verified by SciePro's Medical Advisory Board.