Sciatic nerve Sciatic nerve The sciatic nerve (also called "ischiadic nerve", "ischiatic nerve") is a large nerve in humans and other animals. It begins in the lower back and runs through the buttock and down the lower limb. It is the longest and widest single nerve in the human body, going from the top of the leg to the foot on the posterior aspect. The sciatic nerve provides the connection to the nervous system for nearly the whole of the skin of the leg, the muscles of the back of the thigh, and those of the leg and foot. It is derived
Nerve supply to the skin almost any given stimulus to the human skin can potentially activate a very large number of nerve terminals. Therefore, it is more likely that a stimulus caused by the prick of a needle be detected by more than a hundred nerve endings all sharing the same receptive field, than for that same needle prick to be detected by only one nerve ending. The different kinds of sensory stimuli that are picked up by sensory neurons are grouped into two categories: epicritic and protopathic. Epicritic neurons detect gentle touch such as caresses; light vibrations; the ability to recognize the shape of