Radiating pain down the leg may be caused by Piriformis Muscle Syndrome. The piriformis muscle runs from the sacrum to the femur. The muscle is a large and powerful muscle. The sciatic nerve leaves the pelvis and runs underneath the piriformis muscle. If the piriformis muscle becomes injured or spasmed it can compress the sciatic nerve. This can produce pain, numbness, tingling, loss of sensation, or muscle weakness down the leg. This is one of the many causes of sciatica.
Causes of Piriformis Muscle Syndrome
Multiple causes of piriformis syndrome have been found. Sacroiliac disease, bursitis, degenerative changes in the muscle or tendon, inflammation, or trauma all could lead to the piriformis muscle to spasm.
Often times overuse of the piriformis is caused by injury or degenerative changes elsewhere in the pelvis or lumbar spine. Lower back injuries may causes changes in the lower spine, leading to the pelvis tipping forward or backward. The change in pelvis tip requires the piriformis to work harder day to day, leading to overuse and spasm, resulting in compression of the sciatic nerve.
Signs and Symptoms of Piriformis Syndrome
Radiating sciatic pain is the most common symptom. The pain and change in sensation can occur anywhere along the sciatic nerve. People often describe burning or loss of sensation along the leg. If Piriformis Syndrome progresses the muscle weakness and loss of muscle mass becomes worse.
The pain is most common in the sacral and gluteal regions. It increases with sitting or walking, and decreases with lying. Activities that cause the piriformis muscle to contract or stretch should increase the symptoms. Tenderness is often found with palpation of the gluteal region and may reproduce the radicular pain.
Treatment for Piriformis Syndrome
Since the piriformis spasm is compressing the nerve, treatment goals are to reduce the piriformis muscle spasm. Stretching, massage therapy, electric therapy, and manual therapy are all excellent treatment options to quickly reduce the spasm. Exercises to increase strength and stability in other pelvic or core muscles may be used to reduce stress on the piriformis muscle.
If the Piriformis Syndrome is caused by injuries in the low back, sacroiliac, or pelvis, treatment will address the other regions also.
Piriformis Syndrome is often misdiagnosed in patients, especially with history of chronic low back pain. Successful treatment requires proper diagnosis and appropriate therapy for Piriformis Syndrome.