Piriformis Syndrome is a disorder caused when the piriformis muscle compresses the sciatic nerve. The resulting pain, tingling, and numbness in the buttocks may be mistaken for sciatica, because the pain is along the path of the sciatic nerve.
The piriformis muscle flexes with almost every motion of our hips and legs. The muscle is located deep in the buttock, behind the gluteus maximus, and connects to the upper surface of each femur (thighbone). The muscle lifts and rotates the thigh away from the body, enabling us to walk and shift our weight from one foot to another. Basically, the piriformis muscle helps us maintain balance.
Piriformis Syndrome usually only affects one hip at a time, though both hips may experience Piriformis Syndrome at some point. Having this condition once greatly increases the chance that it will recur unless you take preventative action.
The sciatic nerve rests underneath the piriformis muscle; however, in about 15% of the population, the sciatic nerve passes through the piriformis muscle. People with the sciatic nerve running through the piriformis muscle are more likely to suffer from Piriformis Syndrome than others.
Piriformis Syndrome is sometimes known as “wallet sciatica” or “fat wallet syndrome,” because the condition can be caused or aggravated by sitting with a large wallet in the affected side’s rear pocket.
What are the Symptoms of Piriformis Syndrome?
Individuals with Piriformis Syndrome can experience a variety of symptoms, which may occur intermittently or chronically persist.
Typically, patients describe the symptoms as acute tenderness or pain in the buttock muscle, which may radiate down the back of the leg into the hamstring muscles and sometimes even the calf muscles. Confusing Piriformis Syndrome pain with a hamstring strain is common. However, unlike an actual hamstring strain, the hamstring muscle is not tender to the touch in the case of Piriformis Syndrome.
Typical Piriformis Syndrome symptoms may include:
- A dull ache or pain in the buttock or hip area, which is the most common symptom.
- Pain down the back of the thigh, calf, and foot.
- Pain when walking up stairs or inclines.
- Pain with bowel movements may be present.
- Increased pain after prolonged sitting.
- A reduced range of motion of the hip joint.
Symptoms of Piriformis Syndrome typically worsen after prolonged sitting, prolonged standing, squatting, walking or running, and even climbing stairs. Often, the pain from Piriformis Syndrome lessens when patients lie on their back.
In addition, Piriformis Syndrome pain may be relieved by walking with the foot on the side suffering from the pain pointing outward. This position externally rotates the hip, lessening the stretch on the piriformis and slightly reducing the pain.
The pain symptoms of Piriformis Syndrome are similar to sciatica; however, true sciatica is not the result of compression of the sciatic nerve by the piriformis muscle, but rather the compression of nerves in the spine. Consequently, misdiagnosis of Piriformis Syndrome is common.
What Causes Piriformis Syndrome?
The exact causes of Piriformis Syndrome are unknown. However, it is possible that overuse or strain causes the piriformis muscle to spasm, resulting in pressure on the sciatic nerve. For example, repetitive motions performed during activities such as running or lunging can stress the piriformis muscle.
One theory is that people who regularly run, bicycle, or participate in other forward-moving activities and exercises may be more susceptible to developing Piriformis Syndrome. The lack of lateral, or side, stretching and strengthening exercises can develop very tight adductor (inward flexing) muscles which can cause the piriformis muscle to shorten and lead to Piriformis Syndrome.
Other suspected causes include:
- Muscle spasm in the piriformis muscle, either because of irritation in the piriformis muscle itself, or irritation of a nearby structure such as the sacroiliac joint or hip.
- Tightening of the muscle, in response to injury or spasm.
- Swelling of the piriformis muscle, due to injury or spasm.
- Bleeding in the area of the piriformis muscle.
- Cerebral palsy.
- Direct trauma to the piriformis muscle, such as in a fall or from a knife wound.
- Total hip arthroplasty (surgical repair).
The pain from Piriformis Syndrome can also occur along with bona fide sciatica pain.
How is Piriformis Syndrome Diagnosed?
There is not a definitive test for Piriformis Syndrome; therefore, diagnosing the syndrome is largely a process of ruling out possible conditions caused by a patient’s symptoms.
- Physical exam. An exam of the hip and legs to see if movement causes increased low back pain or lower extremity pain. Typically, the movement of the hip can recreate the pain. A physical exam can identify, or rule out, other possible causes of sciatica pain.
- Medical history. The medical history will include an in-depth review of symptoms, including what positions or activities make the symptoms better or worse. It also includes an analysis of conditions that may be in the patient’s family, such as arthritis.
- Radiologic tests. X-rays, MRIs, and other radiologic tests may be required to rule out other causes of sciatic nerve compression that can cause symptoms similar to Piriformis Syndrome.
- FAIR test. The test detects tightness or other discomforts of the sciatic nerve as it passes through or under the Piriformis muscle
- Magnetic Resonance Neurography (MRN). The direct imaging of nerves in the body, which is useful in the diagnosis of Piriformis Syndrome, and verifying the effect of treatments for the syndrome.
- If the pain goes away after an injection of an anesthetic (with or without steroids) into the piriformis muscle, the pain is probably from Piriformis Syndrome.
When correctly diagnosed, Piriformis Syndrome is usually readily treatable. However, some individuals may suffer from a recurrence of the symptoms or experience chronic discomfort.
How is Piriformis Syndrome Treated?
There are a variety of Piriformis Syndrome treatments. Unfortunately, there is no universal consensus on how to best treat Piriformis Syndrome. The first-line of therapy focuses on resting the muscle and avoiding activities that are painful, which likely means no running, bicycling, and other weight bearing activities.
As treatment continues, the focus moves to carefully and progressively stretching the piriformis muscle. The initial treatment for Piriformis Syndrome can include the following non-surgical therapies:
- Ice Pack / Ice Massage. At the onset of acute pain, apply an ice pack on the painful area for approximately 20 minutes. Repeating as needed every 2 to 4 hours. In some cases, it may be helpful to combine a gentle massage with the ice.
- Heat Therapy. Pain management after the first 24 hours utilizes heat. A heating pad is placed on the muscle for 20 minutes at a time to help reduce inflammation and pain.
- Massage. Proper massage helps speeds the healing process by increasing blood flow to the inflamed area and stopping muscle spasms.
- Most episodes of pain include inflammation; therefore, non-steroidal anti-inflammatory medications (NSAIDs), such as ibuprofen or naproxen, may help decrease inflammation in the affected area.
- Piriformis injection. A local anesthetic (in some instances, along with a corticosteroid) may be injected directly into the piriformis muscle to help decrease spasms and pain. The purpose is to reduce acute pain and help patients progress through physical therapy.
- Botox injection. If persistent piriformis spasms are resistant to anesthetic/corticosteroid injections, an injection of botulinum toxin (Botox®), a muscle weakening agent, may be useful. The goal is to help the muscle relax and contribute to reducing pressure on the sciatic nerve.
- Iontophoresis. A therapy using a mild electric current to deliver medication to the muscle through the skin. In this procedure, an electrode with the medication is energized with a low voltage current to drive the ions through the skin into the muscle.
- Electrotherapy. The application of a transcutaneous electrical nerve stimulation (TENS) unit or interferential current stimulator (IFC) can help to block pain and reduce muscle spasm related to Piriformis Syndrome.
The goal is to help the patient progress with stretching and physical therapy so that the muscle will remain stretched and relaxed.
Stretching and Physical Therapy for Piriformis Syndrome
Physical therapists use stretching exercises that target the piriformis muscle. Depending on the patient, the treatment may also include the hamstrings and hip muscles to reduce pain and increase the range of motion. Stretching helps decrease the painful symptoms of Piriformis Syndrome and return the range of motion.
Physical therapy includes:
- Stretching exercises assist in strengthening the piriformis muscle and other hip muscles and increase the flow of blood through the muscle. In addition to basic stretching, a comprehensive physical therapy and exercise program may be developed.
- Range of motion exercises. A customized program of stretching and range of motion exercises will help stretch the muscle and decrease spasms.
- Deep massage, when performed by a physical therapist, helps enhance healing by increasing blood flow to the area and decreasing muscle spasm.
Can Piriformis Syndrome be Prevented?
Since Piriformis Syndrome is usually the result of sports or movements that repeatedly stress the piriformis muscle (such as running or lunging), prevention is often related to good physical form and minimizing stress on the body. Here are various measures that can be implemented to help:
- Avoid running or exercising on hills or uneven surfaces.
- Properly warm up and stretch before engaging in strenuous physical activities.
- Increase exercise intensity gradually.
- Maintain proper form, posture, and balance while sitting, standing, running, walking, and exercising.
- If pain occurs, stop the activity and rest until the pain subsides.
- Avoid strenuous physical activities that can potentially cause or exacerbate Piriformis Syndrome. If you experience pain or discomfort in the gluteal area during exercise, then cease the activity to prevent further injury.
- Avoid periods of prolonged sitting on hard surfaces.
- Avoid sitting on your wallet.
What Are the Risk Factors for Piriformis Syndrome?
Various risk factors may make some individuals more likely to develop Piriformis Syndrome than others.
- Some studies suggest it is more common in females by a 6:1 ratio. The reason is thought to be due to anatomical differences.
- Anatomical variation in the positioning of the sciatic nerve in relationship to the piriformis muscle may lead to Piriformis Syndrome. In some people, the sciatic nerve traverses through the piriformis muscle, perhaps increasing the likelihood of sciatic nerve compression.
- Direct trauma or injury to the buttock area can lead to swelling, hematoma formation, or scarring, which may lead to compression or entrapment of the sciatic nerve.
- Prolonged sitting may result in direct compression of the sciatic nerve, especially if a person is not sitting properly or is sitting on a large wallet. The syndrome is sometimes referred to as “fat wallet syndrome” or “wallet sciatica,” because it often occurs in people continually sitting on their wallet on a hard surface.
- Overuse or repetitive movements, such as long-distance walking, running, cycling, or rowing can lead to inflammation, spasms, and hypertrophy (enlargement) of the piriformis muscle. These exercises can increase the likelihood of irritating the sciatic nerve.
Novus Spine & Pain Center
Novus Spine & Pain Center is in Lakeland, Florida, and specializes in treating Piriformis Syndrome. By using a comprehensive approach and cutting edge therapies, we work together with patients to restore function and regain an active lifestyle, while minimizing the need for opiates.
Piriformis Syndrome Resources
What is Piriformis Syndrome (Spine-Health.com)
Piriformis Syndrome (Web MD)
Piriformis Syndrome (Wikipedia)
Piriformis Syndrome (Sports Injury Clinic.net)
Piriformis Syndrome (eMedicine Health)
Piriformis Test (Physio-pedia.com)