The saphenous nerve: an external method for identifying its exit from the adductor canal.

The saphenous nerve is the largest and longest branch of the femoral nerve. At its proximal origin, it travels with the femoral artery. The nerve passes lateral to medial in the adductor canal to emerge subcutaneously and supply the medial side of the knee. This investigation analyzes the course of the nerve in 24 lower extremities (12 right, 12 left) and offers a standardized measuring system for externally pinpointing the nerve's exit from the canal. This study may benefit physicians who treat patients with knee pain of obscure etiology. It probably will have direct application to saphenous nerve injection by physicians as part of a pain-management program.