Piriformis syndrome causes pain in the buttock which may radiate down the leg. It is due to the sciatic nerve being impinged by a tight piriformis muscle deep in the buttocks.
Piriformis syndrome symptoms consist of 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.
It is common for pain to initially be confused with a hamstring strain or hamstring origin tendinopathy. However there will be no area in the hamstrings which is tender to touch. Other signs include reduced range of motion of the hip joint, especially into internal hip rotation is often seen.
It is usually overuse which causes the pirofirmis muscle to go into spasm resulting in pressure on the sciatic nerve. The piriformis muscle is one of the small muscles deep in the buttocks that rotates the leg outwards. It runs from the sacrum bone at the bottom of the spine and attaches to the thigh bone or femur roughly near the outside crease of the buttocks.
The sciatic nerve runs very close to this muscle and in around 10% of the population it actually passes straight through the muscles fibers. If the piriformis muscle becomes tight it can compress the sciatic nerve and cause pain which can radiate down the leg, commonly known as sciatic pain.
It has been suggested that this condition would be better referred to as piriformis impingement due to the impingement of the sciatic nerve. A common cause of piriformis syndrome is tight adductor muscles on the inside of the thigh. This means the abductors on the outside cannot work properly and so put more strain on the piriformis muscle.
Piriformis syndrome Treatment
Treatment consists of two phases. First reducing pain by relaxing the muscle through ice / heat, electrotherapy, massage and stretching, then when pain allows strengthening the muscle to help prevent the injury recurring.
If the injury is acutely painful or inflamed then applying ice may help reduce muscle spasm. More chronic or longer term conditions may respond better to heat therapy to relax the muscle. Heat should not be applied if an acute injury, inflammation or recent tear of the muscle is suspected as it will only increase swelling, inflammation and bleeding. Applying heat before performing exercises, particularly stretching exercises may help increase the effectiveness of the exercises.
A doctor may prescribe anti inflammatory medication such as ibuprofen to reduce pain and inflammation. A professional therapist may use sports massage or electrotherapy such as ultrasound to relax the muscle. For more stubborn conditions Botox injections may be indicated and occasionally surgery is required.
Read more on treatment and rehabilitation.
Stretching exercises for the piriformis muscle and other external rotator muscles of the hip should be done as well as adductor muscle stretches. Piriformis muscle stretching should be done at least three times a day in the early stages, reducing frequency as symptoms improve. Stretches should be held for around 20 seconds and done in sets of 3 to 5.
When pain allows exercises to strengthen the piriformis muscle can be done which should help prevent the injury returning. These include clam exercise, hip extension and hip abduction exercises.
See more on piriformis syndrome exercises.