Conditions 

Piriformis syndrome

Piriformis syndrome is pain and numbness in your buttocks and down the back of your leg. It occurs when the piriformis muscle in the buttocks presses on the sciatic nerve.

The syndrome, which affects more women than men, is uncommon. But when it occurs, it can cause sciatica.

Causes

The piriformis muscle is involved in nearly every movement you make with your lower body, from walking to shifting weight from one foot to the other. Beneath the muscle is the sciatic nerve. This nerve runs from your lower spine down the back of your leg to your foot.

Injuring or irritating the piriformis muscle can cause muscle spasms.The muscle may also swell or tighten from the spasms. This puts pressure on the nerve beneath it, causing pain.

Overuse can cause swelling or injure the muscle. Muscle spasms may come from:

• Sitting for long periods
• Over exercising
• Running, walking, or doing other repetitive activities
• Playing sports
• Climbing stairs
• Lifting heavy objects

Trauma can also cause muscle irritation and damage. This may be caused by:

• Car accidents
• Falls
• Sudden twisting of the hip
• Penetrating wounds

Symptoms

Sciatica is the main symptom of piriformis syndrome. Other symptoms include:

• Tenderness or a dull ache in the buttock
• Tingling or numbness in the buttock and along the back of the leg
• Difficulties in sitting
• Pain from sitting that grows worse as you continue to sit
• Pain that gets worse with activity
• Lower body pain that is so severe it becomes disabling

The pain usually affects just one side of the lower body. But it can also occur on both sides at the same time.

Diagnosis

Your health care provider will:

• Do a physical examination
• Ask about your symptoms and recent activities
• Take your medical history

During the exam, your provider may put you through a range of movements. The point is to see if and where they cause pain.

Other problems can cause sciatica. For instance, a slipped disk or arthritis of the spine can put pressure on the sciatic nerve. To rule out other possible causes, you may have an MRI or a CT scan.

Prevention

To prevent future pain:

• Get regular exercise.
• Avoid running or exercising on hills or uneven surfaces.
• Warm up and stretch before exercising. Then gradually increase the intensity of your activity.
• If something causes you pain, stop doing it. Don’t push through the pain. Rest until the pain passes.
• Don’t sit or lie down for long periods in positions that put extra pressure on your hips.