The sciatic nerve - also known as ischiadic nerve - is a large nerve arising from the sacral plexus that innervates the muscles of the pelvis and thigh.

This nerve originates from the ventral branches (anterior rami) of the fourth and fifth lumbar nerves (L4 - L5) and first, second and third sacral nerves (S1 - S3).

It exits the pelvic cavity via the infrapiriform foramen and then descends along the posterior surface of the obturator internus muscle, superior gemellus muscle, inferior gemellus muscle and quadratus femoris muscle. Further, the sciatic nerve passes between the muscles of the posterior group of the thigh and the adductor magnus muscle.

Upon reaching the upper part of the popliteal fossa, the sciatic nerve splits into two terminal branches: the tibial nerve and the common peroneal nerve - also called the common fibular nerve.

On its course, the sciatic nerve gives off several motor branches that supply the muscles of the pelvic girdle - obturator internus, superior gemellus, inferior gemellus, quadratus femoris, and the muscles of the thigh - biceps femoris muscle, semitendinosus muscle, semimembranosus muscle, adductor magnus.

Unlock with Premium

Sciatic nerve (Ischiadic nerve)