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Sciatic Nerve Anatomy


Every person has two sciatic nerves — one on the right and one on the left of the lower limbs. The sciatic nerve is also the largest and longest nerve in the body and measures around 2 cm in diameter.

The sciatic nerve starts in the lower back of the thigh and leg and ends at the foot. The sciatic nerve is connected to the Lumbar and Sacral part of the back. L4, L5, S1, S2, and S3. These five fibers are grouped together and are near the piriformis muscle. These fibers are responsible for the motor and sensory functions of the lower body.

The sciatic motor functions are

*Knee flexion (bending the knee)

*Hip adduction (bringing the thighs together, movement of the leg toward the midline of the body *Plantar flexion, pointing the foot downward *Dorsiflexion, pointing foot upward *Flexion of toes, toes pointing downward *Extension of the toes, toes pointing upward

When a person notices that the functions above are limited, it could be due to a compressed sciatic nerve.

The sciatic nerve also produces sensations to the skin. Some symptoms you may feel are burning, tingling, and numbness.

Areas you may feel these sensations:

*Front, back, and outer part of the thigh *Front, back, and outer part of the lower leg *The top and outer side of the foot *Sole of foot *The web between the first and second toes

An irritated, inflamed, and/or compressed sciatic nerve is called sciatica. According to spine-health.com, 10% to 40% of the population is affected by sciatica at some point in their lives.

See a video by Spine-Health.com https://www.spine-health.com/video/sciatic-nerve-anatomy-video?jwsource=cl

image by: medicalartlibrary.com

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