A Unique Quadrifurcation of the Sciatic Nerve in the Lower Leg

Sciatic nerve is the largest nerve of the body supplying the entire posterior aspect of the lower limb. Taking its origin from the lumbosacral plexus, the nerve divides into its terminal branches at the superior angle of the popliteal fossa. Variant division patterns of the nerve especially those occurring in the thigh and the popliteal fossa are common. Divisions of the nerve occurring in the leg are rare. Even much rarer are terminations involving multiple branching patterns. Variations in the course and distribution of the sciatic nerve are of great importance in neurology, orthopedics, rehabilitation, anesthesia and many other clinical procedures. In the present study, we report a unique quadrifurcation termination of the sciatic nerve occurring deep in the distal half of the leg as observed during routine dissection by the medical students. Due to its variant muscular innervations, quadrifurcation and low divisions of the sciatic nerve may be of great importance in procedures such fracture management of the leg and foot, physiotherapy, limb amputation and in sports medicine. Embryologically, late separation of the common nerve sheath into individual terminal branches may lead to the lower division of the nerve.