Overview
Sciatica is a debilitating condition in which the patient experiences pain and/or paresthesias in the sciatic nerve distribution or an associated lumbosacral nerve root. Often, a common mistake is referring to any low back pain or radicular leg pain as sciatica. Sciatica is specific to the pain that is a direct result of sciatic nerve or sciatic nerve root pathology. The sciatic nerve is made up of the L4 through S2 nerve roots, which coalesce at the pelvis to form the sciatic nerve. At up to 2 cm in diameter, the sciatic nerve is easily the largest nerve in the body. Sciatica pain often is worsened with flexion of the lumbar spine, twisting, bending, or coughing.
The sciatic nerve provides direct motor function to the hamstrings, lower extremity adductors, and indirect motor function to the calf muscles, anterior lower leg muscles, and some intrinsic foot muscles. Also, indirectly through its terminal branches, the sciatic nerve provides sensation to the posterior and lateral lower leg and the plantar aspect of the foot. It is an important distinction to know that most cases of sciatica result from an inflammatory condition leading to an irritation of the sciatic nerve. Conversely, direct compression of the nerve leads to more severe motor dysfunction, which is often not seen, and if present, would warrant a more meticulous and expeditious workup.