Nerve · Neck

Supraclavicular nerves

Nervi supraclaviculares

A fan of three nerves that descend from a common stem under the back edge of sternocleidomastoid and spread over the collarbone to supply the skin of the shoulder cap and the upper chest — medial branches over the sternoclavicular joint, intermediate over the clavicle itself, lateral over the point of the shoulder. Some of the lateral twigs pierce the clavicle's periosteum rather than crossing it, so the bone and the skin above it share a nerve. They come from C3 and C4, the same segments that supply the diaphragm through the phrenic nerve, which is why the skin over the shoulder tip and the underside of the diaphragm are wired into the same levels of the spinal cord.