Median Nerve Branch to Flexor Carpi Radialis

ramus nervi mediani ad musculum flexorem carpi radialem

The motor branch of the median nerve to flexor carpi radialis arises in the proximal forearm, usually from the same neural segment as the pronator teres branch. FCR innervation is an important localisation landmark in median nerve injury assessment, as its denervation distinguishes elbow-level from distal forearm median nerve injuries.

Region: Forearm

Clinical Relevance

Clinical Notes

FCR denervation indicates a median nerve lesion at or proximal to the proximal forearm level. In pronator syndrome, the FCR branch is typically involved producing wrist flexion weakness alongside the finger flexor weakness. The FCR branch is assessed by EMG needle placement in the FCR belly and is distinct from the AINS, which provides no FCR innervation. Preservation of FCR function in anterior interosseous nerve palsy confirms the distal branch lesion pattern.

Pathology

Common Injuries & Conditions

Pronator Syndrome

Median nerve compression in the proximal forearm affecting the FCR and FDS branches along with AINS, producing weakness of wrist flexion, FDS, and intrinsic hand muscles with proximal forearm aching and a positive pronation provocative test.