Nerve to Anconeus

nervus musculi anconei

The nerve to the anconeus is a branch of the radial nerve arising in the radial groove or just below it, supplying the anconeus muscle at the posterolateral elbow. The anconeus is a small triangular muscle extending from the lateral epicondyle to the olecranon that assists in elbow extension and in stabilising the ulna during forearm rotation. As a branch of the radial nerve, the nerve to anconeus is spared in posterior interosseous nerve lesions distal to the branch point.

Region: Forearm

Clinical Relevance

Clinical Notes

The nerve to anconeus is important in surgical anatomy of the radial nerve and in motor nerve transfer procedures. In elbow surgery via the Kaplan or Kocher lateral approaches, the nerve to anconeus entering the muscle from the posterior aspect must be identified and protected. In reinnervation procedures for radial nerve palsy, the nerve to anconeus (since the anconeus is expendable) can be used as a donor nerve for motor nerve transfer to the posterior interosseous nerve or to the long head of triceps branch to restore elbow and wrist extension. The anconeus is an elbow stabiliser and its innervation is tested in comprehensive radial nerve assessment.

Pathology

Common Injuries & Conditions

Nerve to Anconeus as Donor in Radial Nerve Reconstruction

In radial nerve palsy from humeral shaft fracture, the expendable nerve to anconeus provides a nearby motor donor nerve for nerve transfer to the posterior interosseous nerve or wrist extensor branches, providing reinnervation without sacrificing a critical motor unit and allowing earlier recovery than nerve grafting from a remote donor site.