Piriformis syndrome[1] is a rare neuromuscular disorder. Piriformis syndrome is a condition which occurs when the sciatic nerve gets compressed by the piriformis muscle.
The buttocks consist of several small muscles at its deeper side. The piriformis muscle belongs to these small muscles present at the deeper side of the buttock that helps the legs to rotate outwards. The piriformis muscle is the muscle that passes through the sacrum of the spine and connects with the femur or the thigh bone near the crease present at the outer side of the bum. A long and thick nerve known as sciatic nerve runs along this muscle all along the backside of the leg, which ultimately gets divided into small branches that end in the feet. It is found that in some people this sciatic nerve passes directly through the muscle fibers. Tightening of piriformis muscle pressurizes the sciatic nerve resulting in severe pain, which can further spread down through the leg; this condition is also commonly called as sciatic pain. In some rare cases, this condition is also referred to as piriformis impingement because of the impingement on the sciatic nerve. The piriformis syndrome often occurs due to tight adductor muscles present at the inner side of the thigh. As a result abductors present at the outer side fail to work appropriately due to which piriformis becomes over strained.
Piriformis muscle helps in performing movement of the lower body, as it is responsible for stabilizing the joint of the hip and lifting and rotating the thigh away from body. Piriformis muscle not only helps while walking and shifting the weight from one foot to another, but also maintains the balance. Piriformis muscle is used in sports activities that often involve almost all movement of legs and hips especially while rotating and lifting of thighs.
Types of Piriformis Syndrome
Piriformis Syndrome Is Broadly Classified Into Two Types
- Primary Piriformis Syndrome
- Secondary Piriformis Syndrome
Primary Piriformis Syndrome: Primary piriformis syndrome is caused anatomically like in case of split sciatic nerve, an abnormal sciatic nerve path or split piriformis muscle.
Secondary Piriformis Syndrome: Secondary piriformis syndrome is caused by a precipitating cause that includes ischemic mass effect, local ischemia, macrotrauma, and microtrauma.
Piriformis syndrome is a condition, which most often occurs due to macrotrauma to the buttocks that result in inflammation of the muscle spasm or soft tissue, or both, leading to compression of nerve. Microtrauma may also be caused from overuse of the piriformis muscle like in long-distance running or walking and by direct compression. Wallet neuritis such as repetitive trauma resulting from sitting on hard or thick surfaces could be taken as a good example for this type of direct compression.
Causes and Risk Factors of Piriformis Syndrome
Piriformis syndrome is caused due to inflammation and irritation of sciatic nerve, which often results from spasm, hypertrophy, and excessive tightness of piriformis muscle. However, there are many more causes that may result in piriformis syndrome which may include:
Trauma: Traumatic fall in the seated posture may precisely injure the sciatic nerve and may also cause secondary nerve compression because of swelling and gluteal muscle contusion.
Other Causes of Piriformis Syndrome May Include
- Twisting and bending while picking up an object from the floor.
- Carrying heavy objects on the stairs.
- Downhill running.
- Sitting for long periods in crossed leg position or on a hard surface.
- Malalignment in the bones of the lower extremities like flatfeet and knocked knees resulting in excess rotation of hips during runs and walks.
- Maternity, poor posture and tightness in the muscle.
- Spine, particularly lumbar spine pathology.
- Sacroiliac joint pathology.
- Excessive exercise training that involves gluteal and hip muscles.
Signs and Symptoms of Piriformis Syndrome
- Pain is experienced down side at the back of calf, foot and thigh.
- Pain is also felt while walking up the stairs or any inclines.
- Exacerbation of pain followed by prolonged sitting.
- Tingling in the buttocks.
- Tenderness in the muscle area.
- Pain is also felt in the buttocks.
- Numbness in the buttocks.
- Pain radiating down the back of the leg into the hamstrings and sometimes into the calf muscles.
- Pain in some cases could also be similar to hamstring strain and hamstring origin tendinopathy, but not actually a hamstring pain as there is no tenderness found in that area.
- Decreased range of motion in the hip joint, particularly in internal hip rotation is also noticeable.
Treatment for Piriformis Syndrome[4]
The initial step taken to treat piriformis syndrome often involves avoiding the activities or sitting postures that are responsible for triggering the pain. Heat, rest and ice may help also help in controlling the symptoms. Physical therapy involving stretches and exercises may also be helpful in reducing the compression on sciatic nerve. Medications like muscle relaxants, injections with corticosteroids or anesthetics, and anti-inflammatory drugs are also prescribed to treat piriformis syndrome. Apart from this other therapies like iontophoresis,[3] in which mild electric current is used for treating disorders and injection with botulinum toxin are also used in some cases. Surgery is performed in very severe cases where conservative treatments fail to work appropriately.
Application of ice to the affected area for about 15 to 20 minutes in every four hours all over the day helps controlling the symptoms.
Physical Therapy for Piriformis Syndrome
Physical therapy is required for all the patients to speed up the healing process and restore normal functioning. PT for Piriformis Syndrome may include:
- Joint mobilization.
- Ultrasound.
- Soft tissue massage.
- Application of heat and ice.
- Orthotics.
- Exercises to improve flexibility, strength, pelvic stability and balance, and core stability and endurance.
- Electrical stimulation.
- Stretching exercises.
- Postural training.
- Muscle energy techniques.
- Activity modification.
- Functional foot orthoses.
Prevention for Piriformis Syndrome
- Maintaining good flexibility of the lower extremity and trunk muscles.
- Maintaining strength of the gluteal and abdominal muscles.
- Sitting with feet flat on ground.
- Adjusting the seat in order to keep the knees and hips comfortably bent while driving.
- Sitting with a wallet in the back pocket must be avoided.
- Maintaining perfect posture while standing, lifting, and sitting.
- Do not lift with the back bent, preferable to also bend the knee to pick the object.
- Keeping the objects close to the body during lifts.
- Avoidance of combined lifting and twisting motions with the feet firmly planted on the floor. Instead feet should be in motion and the object should be placed directly in front of the body.
- Appropriate warm up before beginning activity or sport.
Exercises for Piriformis Syndrome
Gluteal Stretch For Piriformis Syndrome: This exercise is performed by lying down on back and bending both the knees. Now by relaxing the ankle of injured leg over the knee of the healthy leg grab the thigh of injured leg from the uninjured side in order to pull it toward the chest until a pain-free stretch is felt along the buttocks on the affected side and probably along the outer side of the hip. Hold the position for about 15 to 30 seconds and release. Repeat three times ensuring there is no exacerbation of symptoms.
Standing Hamstring Stretch For Piriformis Syndrome: This exercise is performed by putting the heel of the injured side on about a 15 inches high stool. By keeping the leg straight lean in the forward direction and bend towards the hips until a mild to moderate pain-free stretch is felt in the back of the thigh. Rolling the shoulders or bending of waist while performing this exercise must be strictly avoided as this could lead to stretching of lower back other than leg. Hold the position for about 15 seconds and release. Repeat three times ensuring there is no exacerbation of symptoms.
Resisted Hip Abduction For Piriformis Syndrome: This exercise is performed by standing sideways near the door with the injured side away from the door. Now take an elastic tubing and place one end around the ankle on your injured side. Make a knot on the other end of the tubing and close the knot in the door near the floor. Now pull the tubing out to the side keeping the leg straight and return to the starting position. Do two sets of 15. Resistance can be increased by moving farther away from the door.
Partial Curl For Piriformis Syndrome: This exercise is performed by lying down in a straight position and bending the knees and keeping the feet flat on floor. Now draw the abdomen in order to tighten the muscles of the stomach. By stretching the hands in forward direction, curl the upper body in the forward direction until the shoulders clear the floor. Hold the position for about three seconds and release. Avoid holding breath while performing this exercise. It helps to breathe out while lifting the shoulders. Repeat this exercise for about 10 times. Perform two sets of 15 ensuring there is no exacerbation of symptoms. For increasing the challenge, clasp the hands behind the head and keep the elbows out to the sides.
Prone Hip Extension For Piriformis Syndrome: This exercise is performed by lying down on the stomach and placing a pillow beneath the hips. By bending the knee on affected side, draw belly button in towards the spine in order to tighten the muscles of abdomen. Lift the leg about six inches above the floor. Keep the other leg straight. Hold the position for about five seconds and release. Perform two sets of 15 ensuring there is no exacerbation of symptoms. Then, the repeat the same on other leg.
Clam Exercise For Piriformis Syndrome: This exercise is performed by lying down straight on the unaffected side by bending knees and hips keeping the feet together at the same time. Now by joining the heels together gradually raise the upper leg towards the ceiling. Hold the position for about two seconds and release. Perform two sets of 15 ensuring there is no exacerbation of symptoms.
Investigations To Diagnose Piriformis Syndrome[2]
A medical history and thorough subjective evaluation is performed to diagnose piriformis syndrome. A physical examination of back is performed to determine sciatic nerve irritation and movements of leg and hip exhibits the exacerbation of symptoms.
Other Tests That Help In Ruling Out Any Injury And Spine Pathology May Include:
- X-rays.
- Computed Tomography (CT) Scan.
- Magnetic Resonance Image (MRI).