Piriformis Syndrome

ByPaul L. Liebert, MD, Tomah Memorial Hospital, Tomah, WI
Reviewed/Revised Nov 2023
VIEW PROFESSIONAL VERSION

Piriformis syndrome is compression of the sciatic nerve by the piriformis muscle (a flat muscle of the buttocks located near the hip), causing pain in the buttocks and occasionally sciatica.

(See also Overview of Sports Injuries.)

The piriformis muscle extends from the pelvic surface of the large triangular bone at the base of the spine (sacrum, or tailbone) to the bony bump (trochanter) at the upper end of the thighbone (femur). During running or sitting, this muscle can compress the sciatic nerve at the site where it emerges from under the piriformis to pass over the hip rotator muscles. Piriformis syndrome is uncommon.

Symptoms of Piriformis Syndrome

A chronic nagging ache, pain, tingling, or numbness starts in the buttocks and can extend down the entire back of the thigh and calf, and sometimes into the foot. Pain worsens when the piriformis is pressed against the sciatic nerve (for example, while sitting on a toilet, a car seat, or a narrow bicycle seat or while running).

Diagnosis of Piriformis Syndrome

  • A doctor's evaluation

Doctors diagnose piriformis syndrome on the basis of the person's symptoms and the results of a physical examination. Doctors may move the leg or ask the person to bend because piriformis syndrome is diagnosed when specific movements cause pain.

Treatment of Piriformis Syndrome

  • Rest

  • Rehabilitation

People should temporarily stop doing any activity that causes pain. If pain is aggravated by sitting, people should stand or, if unable to do so, change positions to remove the source of pressure around the buttock. Specific stretching exercises for the posterior hip and piriformis can be helpful. Nonsteroidal anti-inflammatory drugs (NSAIDs) or other analgesics are used to relieve pain. Sometimes doctors inject a corticosteroid near the site where the piriformis muscle crosses the sciatic nerve to provide temporary pain relief. Surgery is rarely needed.

Stretching Exercises for the Hip and Piriformis
Side-Lying Hip External Rotation (Clamshell Exercise)
1. Lie on involved side. 2. Keep shoulders and hips in line with ankles slightly behind the body with the knees bent ap... read more

Courtesy of Tomah Memorial Hospital, Department of Physical Therapy, Tomah, WI; Elizabeth C.K. Bender, MSPT, ATC, CSCS; and Whitney Gnewikow, DPT, ATC.

Bridging
1. Lie on back with both knees bent and feet on floor/table. 2. Perform abdominal and gluteus maximus contraction and l... read more

Courtesy of Tomah Memorial Hospital, Department of Physical Therapy, Tomah, WI; Elizabeth C.K. Bender, MSPT, ATC, CSCS; and Whitney Gnewikow, DPT, ATC.

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