Nervus ischiadicus

Nervus Ischiadicus (also known as the Sciatic Nerve) is the largest nerve in the human body. It begins in the lower back and runs through the buttock and down the lower limb. It 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.

Anatomy

The Nervus Ischiadicus originates from the sacral plexus, a network of nerve fibres that supplies the lower limb. It is formed from the L4 to S3 segments of the sacral plexus. The nerve passes beneath the piriformis muscle and leaves the pelvis through the greater sciatic foramen. It then descends in the posterior thigh to the popliteal fossa.

Function

The Nervus Ischiadicus is responsible for the innervation of the skin of the foot, and most of the lower leg. It also innervates the muscles in the back of the thigh, leg, and foot. It is involved in the control of numerous muscles and sensation in the lower limbs.

Clinical Significance

Damage to the Nervus Ischiadicus can cause sciatica, a condition characterized by pain that radiates along the path of the sciatic nerve. This pain is often caused by compression of the nerve, such as from a herniated disc in the spine.

See Also

• Peripheral Nervous System
• Sacral Plexus
• Sciatica