The anatomy of the anconeus nerve redefined.

The anconeus nerve is the longest branch of the radial nerve and suitable as a donor for the neurotization of the axillary nerve. The aim of this study was to map its topographical course with reference to palpable, anatomical landmarks. The anconeus nerve was followed in 15 cadaveric specimens from its origin to its entry to the anconeus. It runs between the lateral and the medial head of the triceps before entering the medial head and running intramuscularly further distal. Exiting the muscle, it lies on the periosteum and the articular capsule of the elbow, before entering the anconeus muscle. Two types of anconeus nerve in relation to branches innervating triceps were found: nine nerves also innervated the lateral triceps head, while the other six only contributed two branches to its innervation. The course of the anconeus nerve is important for harvesting as a donor nerve and to protect the nerve in surgical elbow approaches.