Predicting radial nerve location using palpable landmarks.

The purpose of this study is to predict the location of radial nerve (RN) utilizing palpable anatomic landmarks. Thirty-four paired upper limbs were dissected. The RN was localized: (1) at the humeral spiral groove (SG), (2) lateral intermuscular septum (LIS), and (3) at its' division into the posterior interosseous nerve (PIN) and radial sensory nerve (RSN). The PIN was located at the anterior aspect of the radial neck (AN). Humeral and radial lengths were measured. The RN traversed the SG, on average, 48% (36%-63%) of humeral length, distal to the greater tuberosity. The RN pierced the LIS, on average, 38% (29%-56%) of humeral length, proximal to the lateral epicondyle (LE). The PIN/RSN division occurred on average 1.0 cm (-11.4 to 3.5) distal to the LE. The PIN crossed the AN, on average, 10% (5%-14%) of radial length, distal to the radial head articular surface.