Piriformis Syndrome

Piriformis syndrome causes pain that radiates down the back of the leg along the sciatic nerve.

Piriformis syndrome is uncommon; health care professionals diagnose less than 200,000 people with this condition per year in the U.S. This syndrome usually starts with single-leg pain, tingling, or numbness in the back and/or buttock area that can extend down the back of the leg (thigh) following the sciatic nerve and cause sciatic nerve pain. Nerve compression by spasm or contracture of the piriformis muscle causes piriformis syndrome (also termed piriformis muscle syndrome). The piriformis muscle is a flat muscle located in the buttocks. It stabilizes the hip joint and can lift and rotate the thigh away from the body. This muscle pairs with the obturator externus muscle to pull the lower pelvis toward the back.

Pseudo-sciatica, wallet sciatica and hip socket neuropathy are other names for piriformis syndrome. It is often associated with repetitive actions taken during sports (for example, long-distance running, playing tennis, or football injuries with trauma to the buttocks).

Picture of the piriformis muscle

The causes of piriformis syndrome are related to the location of the sciatic nerve in relation to the piriformis muscle; the sciatic nerve passes out of the pelvis by four routes. Spasms or swelling of the piriformis muscle can cause signs and symptoms due to pressure placed on the various areas of the sciatic nerve that are adjacent to the muscle.

Risk factors for piriformis syndrome may include the following, which often occur due to sports injuries:

• Inflammation (any cause such as overuse, sprain)
• Trauma (usually blunt trauma to the buttocks)
• Hematoma
• Scar formation

Individuals who develop the following in or near the piriformis muscles are also at risk:

• Cysts
• Tumors
• Pseudo-aneurysms

Early signs of piriformis syndrome usually occur in the buttocks and may include:

• Pain
• Numbness
• Tingling feeling (like pins and needles pricking the skin)
• Low back pain (sacroiliac and/or sciatic pain)

Later signs of and symptoms and signs of piriformis syndrome may include:

• Extension of pain down the length of the sciatic nerve, as far as the foot
• Severe buttock pain and/or leg pain (leg muscle spasm)

The early and late signs and symptoms of piriformis syndrome may be intermittent; however, they may recur and usually is triggered by:

• Sitting
• Running
• Climbing stairs
• Applying pressure over the piriformis muscle

Is piriformis syndrome the same thing as sciatica and low back pain?

Piriformis syndrome closely mimics the sciatica and low back pain symptoms caused by other mechanisms such as disc nerve entrapment (disc herniation).

A number of different doctors and health professionals may be involved in the treatment of piriformis syndrome.

• Depending on the severity of the symptoms, orthopedic, chiropractic, sports medicine, and rehabilitation physicians may be involved.
• Physical and occupational therapists may be part of the treatment team.
• Infrequently, a surgeon or an OB-GYN physician may be involved if surgery or a vaginal approach to injection therapy in women is needed.

Unfortunately, there is no definitive test for piriformis syndrome. However, frequently the patient has a history of trauma or overuse activity. During the patient's physical exam, palpating or moving the patient's piriformis muscle in certain directions may elicit pain. Because piriformis syndrome is a relatively infrequent cause of sciatica and low back pain (its estimated incidence is about 6%), health care professionals usually perform other tests to rule out other causes of sciatic nerve compression, such as herniated discs, back sprains, lumbosacral spondylolisthesis, spinal stenosis, and many others.

Tests such as X-rays can rule out bone fractures. CT, MRI (magnetic resonance imaging), electromyography (EMG, neurography, or electrophysiologic tests), and injection of trigger points in the piriformis muscle with an anesthetic (lidocaine, for example) can help the physician determine whether the symptoms are due to piriformis syndrome or other conditions like a herniated disc.

Treatment options and medications for piriformis syndrome are usually considered for three different phases: acute phase, recovery phase, and maintenance phase.

• Acute phase: Treatment consists of rest and initial physical therapy, in which an individual performs flexion, rotation, and other basic movements to stretch the piriformis muscle. A physical therapist can administer soft-tissue massage to the gluteal and lumbosacral areas as well as cold packs and occasionally electrical stimulation.
  • Occupational therapy to avoid prolonged sitting that can increase symptoms is also utilized. Infrequently, surgical intervention may release the pressure on the sciatic nerve. Some patients benefit from transrectal massage and/or therapeutic ultrasound treatment. In addition, manual manipulation, often used by osteopathic physicians, can help stretch out the piriformis muscle. Medications used during the acute phase are:
    • Local injection of anesthetics (lidocaine [Xylocaine], bupivacaine [Exparel, Sensorcaine, Marcaine])
    • Oral NSAIDs (nonsteroidal anti-inflammatory drugs) over-the-counter like ibuprofen (Motrin and others), and/or
    • In the US, about 10.3 million Americans aged 12 and older misused opioids.
    • Doctors and other healthcare professionals are now regulated very closely by the US DEA because of potential addiction to opiates like Norco, Vicodin, OxyContin, and other narcotics.
    • Some doctors treat piriformis syndrome with muscle relaxants and/or corticosteroids.
• Recovery phase: Physical therapy is enhanced during this phase; the goal is to strengthen the piriformis and gluteal muscles and optimize their pelvic alignment and progressively correct any overuse or stress on these muscles. Patients may use the same medications described above but with less frequency.
• Maintenance phase: The patient should follow the recommended exercise program for increased stability and strength as suggested by their physician. Because many people who develop piriformis syndrome are athletes, they should slowly resume training over long periods, possibly over several periods of months, depending upon the initial severity of the syndrome. Such athletes can return to competition if they demonstrate a pain-free range of motion and strength of the piriformis muscle; recovery time varies from person to person.

If the diagnosis of piriformis syndrome is performed correctly, surgery can be a good treatment option in patients with refractory sciatica despite appropriate conservative treatments.

Although many individuals, especially professional athletes, who develop piriformis syndrome may require that health professionals assist them with physical therapy, there are also home remedies that can help patients with piriformis syndrome. For example, some physicians suggest that stretches and/or exercises at home be part of the basic rehabilitation program. Home exercises such as lying in bed and then rolling from side to side with the knees flexed and then extended, rotating from side to side standing, lying flat on the back, and moving the legs as if peddling a bicycle may reduce symptoms.

• Taking warm baths, in which the full body is immersed, may also be helpful.
• Cold packs may help reduce inflammation.
• Massage may reduce muscle tension, and yoga may help.
• Some patients use acupuncture to relieve discomfort.

If health care professionals diagnose piriformis syndrome early and the underlying cause is treated, the prognosis usually is good. However; piriformis syndrome in some people is diagnosed later in the disease. A later diagnosis has a less favorable prognosis if the disease has become chronic.

• It is possible to prevent some individuals from getting piriformis syndrome by avoiding overuse of and trauma to the low back/gluteal muscles.
• It is also possible to prevent the recurrence of the syndrome by patient compliance with stretching and flexibility training and exercises.