Piriformis syndrome is a condition that can cause pain and numbness in your buttocks and down the back of your leg. Piriformis syndrome happens when the small muscle that connects the base of your spine to your hip (piriformis muscle) presses on the nerve that runs down the back of your leg (sciatic nerve).
The piriformis muscle helps your hip rotate and helps to bring your leg back and out. It also helps shift your weight while you are walking to keep you stable. The sciatic nerve runs under or through the piriformis. Damage to the piriformis muscle can cause spasms that put pressure on the nerve below. This causes pain and discomfort while sitting and moving. The pain may feel as if it begins in the buttock and spreads (radiates) down your hip and thigh.
The piriformis syndrome refers to sciatica that arises from entrapment of the sciatic nerve by the piriformis muscle. Overuse injury (running, bicycling), weak gluteal muscles, and compression by an oversized wallet (“fat wallet syndrome”) can cause this syndrome.
Symptoms include pain over the buttocks (50%–95%) radiating down the back of the leg and aggravation of pain with sitting (39%–97%).
It occurs more commonly in women and is usually precipitated by trauma. Physical examination reveals external tenderness over the greater sciatic notch (59%–92%) and buttock pain on resisted hip abduction and external rotation when the patient is seated (32%–74%).
With the patient supine, buttock pain with hip flexion, adduction, and internal rotation (FAIR) is also seen along with tenderness of the piriformis muscle on rectal or vaginal examination.
Physical therapy (lateral stretching and strengthening), nonsteroidal antiinflammatory drugs, local steroid injections, and botulinum toxin injections can be beneficial. Nerve compression from herniated disc or facet arthropathy should be ruled out.
What are the causes?
Piriformis Syndrome is caused by pressure on the sciatic nerve from the piriformis muscle.
The piriformis muscle can get irritated with overuse, especially if other hip muscles are weak and the piriformis has to do extra work. Piriformis syndrome can also occur after an injury, like a fall onto your buttocks.
What increases the risk?
Piriformis Syndrome is more likely to develop in:
- People who sit for long periods of time.
- People who have weak buttocks muscles (gluteal muscles).
What are the symptoms of Piriformis Syndrome?
Pain, tingling, or numbness that starts in the buttock and runs down the back of your leg (sciatica) is the most common symptom of Piriformis Syndrome.
Your symptoms may:
- Get worse the longer you sit.
- Get worse when you walk, run, or go up on stairs.
How is Piriformis Syndrome diagnosed?
Piriformis Syndrome is diagnosed based on your symptoms, medical history, and physical exam. During this exam, your health care provider may move your leg into different positions to check for pain.
He or she will also press on the muscles of your hip and buttock to see if that increases your symptoms.
You may also have an X-ray or MRI.
How is Piriformis Syndrome treated?
Treatment for Piriformis Syndrome may include:
- Stopping all activities that cause pain or make your condition worse.
- Using heat or ice to relieve pain as told by your health care provider.
- Taking medicines to reduce pain and swelling.
- Taking a muscle relaxer to release the piriformis muscle.
- Doing range-of-motion and strengthening exercises (physical therapy) as told by your health care provider.
- Massaging the affected area.
- Getting an injection of an anti-inflammatory medicine or muscle relaxer to reduce inflammation and muscle tension.
In rare cases, you may need surgery to cut the muscle and release pressure on the nerve if other treatments do not work.
Follow these instructions at home:
- Take over-the-counter and prescription medicines only as told by your health care provider.
- Do not sit for long periods. Get up and walk around every 20 minutes or as often as told by your health care provider.
- If directed, apply heat to the affected area as often as told by
your health care provider. Use the heat source that your health care provider
recommends, such as a moist heat pack or a heating pad.
- Place a towel between your skin and the heat source.
- Leave the heat on for 20–30 minutes.
- Remove the heat if your skin turns bright red. This is especially important if you are unable to feel pain, heat, or cold. You may have a greater risk of getting burned.
- If directed, apply ice to the injured area.
- Put ice in a plastic bag.
- Place a towel between your skin and the bag.
- Leave the ice on for 20 minutes, 2–3 times a day.
- Do exercises as told by your health care provider.
- Return to your normal activities as told by your health care provider. Ask your health care provider what activities are safe for you.
- Keep all follow-up visits as told by your health care provider. This is important.
How is Piriformis Syndrome prevented?
- Do not sit for longer than 20 minutes at a time. When you sit, choose padded surfaces.
- Warm up and stretch before being active.
- Cool down and stretch after being active.
- Give your body time to rest between periods of activity.
- Make sure to use equipment that fits you.
- Maintain physical fitness, including:
Contact a health care provider if:
- Your pain and stiffness continue or get worse.
- Your leg or hip becomes weak.
- You have changes in your bowel function or bladder function.