A Combined Variation in the Gluteal Region

A combined variation was identified in the left gluteal region of a new-born cadaver. The piriformis muscle consisted of a large upper part and a smaller lower part. The common peroneal nerve and a very small part of the posterior femoral cutaneous nerve passed through these two parts of the muscle. The common peroneal nerve formed the sciatic nerve by combining with the tibial nerve when it reached the lower part of the muscle. The two components of the sciatic nerve ran normally along the thigh in the same sheath, reaching the popliteal fossa,