What is the piriformis muscle?
The piriformis is a muscle that travels behind the hip joint. The piriformis muscle is small compared to other muscles around the hip and thigh, and it aids in external rotation (turning out) of the hip joint. The piriformis muscle and its tendon have an intimate relationship to the sciatic nerve--the largest nerve in the body--which supplies the lower extremities with motor and sensory function. The piriformis tendon and sciatic nerve cross each other behind the hip joint, in the deep buttock. Both structures are about one centimeter in diameter.
What do people think happens in piriformis syndrome?
It is thought that the piriformis muscle tendon may be tethering the sciatic nerve, and causing an irritation to the nerve. While it has not be proven, the theory supported by some physicians is that when the piriformis muscle and its tendon are too tight, the sciatic nerve is choked. This may decrease the blood flow to the nerve and irritate the nerve because of pressure.
What else may be causing this pain?
Sometimes referred to as "deep buttock pain," other causes of this type of pain include spine problems (including herniated discs, spinal stenosis, etc.), sciatica, and tendonitis. The diagnosis of piriformis syndrome is often given when all of these diagnoses are eliminated as possible causes of pain. Other signs of piriformis syndrome include examination maneuvers that attempt to isolate the function of this muscle, and the finding of pain directly over the tendon of the piriformis muscle.
Is there any treatment for piriformis syndrome?
Unfortunately, the treatment of piriformis syndrome is quite general, and often this is a difficult problem to recover from. Some treatment suggestions are:
- Physical Therapy - Emphasis on stretching and strengthening the hip rotator muscles
- Rest - Avoid the activities that cause symptoms for at least a few weeks
- Anti-Inflammatory Medication - To decrease inflammation around the tendon
- Deep Massage - Advocated by some physicians
On some occasions, when these treatment fail, patients have surgery to release, or loosen, the piriformis muscle tendon. This surgery is not a small procedure, and generally considered the last resort if a lengthy period of conservative treatment does not solve the problem.