Sciatic nerve

The sciatic nerve is a mixed nerve that arises from the anterior and posterior divisions of the ventral rami of the fourth lumbar to the third sacral nerves (L4 - S3). It is the largest and longest peripheral nerve not only of the sacral plexus but also of the entire human body, traveling posteriorly through the lower limb. At its origin, it measures approximately 0.79 inches (2 centimeters) in width. The sciatic nerve provides both motor and sensory innervation to the thigh, leg, and foot.