Piriformis block is also known as piriformis injection, piriformis nerve injection or piriformis nerve block. It is an injection near the sciatic nerve designed to treat piriformis syndrome. 

The piriformis syndrome is a condition commonly responsible for pain in the leg and buttocks. Piriformis syndrome occurs when the piriformis muscle, which runs from the anterior part of the sacrum (lower spine) to the outer thigh, spasms or becomes irritated. This puts pressure on the sciatic nerve, causing pain and discomfort. Piriformis syndrome is characterized by pain in the buttocks and often pain in the posterior thigh as well. This pain is often aggravated by physical activity or by sitting down.



A “block” (or nerve block) refers to a procedure in which a physician injects an anesthetic and/or steroid into a problem nerve in order to relieve pain. After numbing the skin with a local anesthetic, a doctor will pass a small needle into the sciatic nerve. The needle stimulates the nerve to fire, causing the muscles along the sciatic nerve to twitch, which indicates that contact has been made with the sciatic nerve.

The physician will then inject a steroid near the sciatic nerve to ease inflammation. Anesthetic and steroid will also be injected into the piriformis muscle itself to reduce the frequency of spasms. The treatment is usually administered in conjunction with physical therapy in order to maximize effectiveness.



The result of a piriformis nerve block typically lasts between 6 to 8 weeks. Some patients experience soreness at the injection site after the procedure, and the local anesthetic can sometimes cause the muscles in the area to lose sensation temporarily.

During the recovery period, it may be recommended to continue with physical therapy and schedule follow-up injection treatments as needed. Many patients also find relief during the recovery period by using heating pads before exercising and icing the area after exercise.