Let’s Make Sense of Sciatica

The Sciatica Series Part I

Today we are kicking off our three part series on sciatica! In Part I, we are discussing the basics– what exactly is the sciatic nerve and why does it cause so many problems in our body?

What is it?—Anatomy of the Problem

The sciatic nerve branches from your lower back all the way through your hips, buttocks, and then down each leg and foot. It is the longest nerve in the body, formed by the union of five nerve roots from the lower spine. It connects the spinal cord with the skin and muscles of your thighs, legs, and feet. The sciatic nerve is made up of a collection of nerve fibers that emerge from the spinal cord, uniting to form a single nerve in front of the piriformis muscle. At its thickest part, the nerve measures 2cm.

The sciatic nerve has many functions: knee flexion, hip adduction, plantar flexion, and dorsiflexion of the foot are its motor functions, while sensations of the front, back, and out parts of the thighs, calves, and feet are its sensory functions.

The sciatic nerve can split in several variations, most commonly by dividing above the piriformis muscle and then through it, or leaving the pelvis below the muscle. When the nerve becomes irritated, compressed, or inflamed through lower back problems, it can create symptoms that are felt along the whole path of the nerve.