Piriformis Syndrome: Overview

Piriformis Syndrome: Overview

This video will provide an overview of piriformis syndrome. Underneath the gluteal muscles lies the piriformis muscle. It begins at the sacrum and attaches to the greater trochanter, a bony bump at the top of the thigh bone. The piriformis plays an important role in stabilizing the hip and rotating the hip out to the side. The sciatic nerve is the largest nerve in the body and provides both sensation and muscle function to the leg and foot. Nerve roots that exit the spine join together to form the sciatic nerve, which travels from the lower back into the buttock and down the leg. In most people, the sciatic nerve passes beneath the piriformis muscle, although in some individuals, it passes through or alongside the muscle.

Compression or irritation of the sciatic nerve can lead to a condition known as sciatica. Sciatica is characterized by pain, numbness, tingling, or weakness that may begin in the lower back or buttock and radiate down the back of the leg. Sciatic nerve compression can occur at several locations, including the spine, the pelvic region, or the gluteal muscle region. Piriformis syndrome is a specific type of sciatica caused by compression or irritation of the sciatic nerve by the piriformis muscle. This irritation can contribute to a cycle of pain, muscle spasm, and inflammation, which may further worsen symptoms over time.

Piriformis syndrome may develop due to a variety of factors, but three common ways include: enlargement or tightness of the piriformis muscle from repetitive motions during athletic activity, like running or jumping; strain from overusing the piriformis muscle to compensate for weak hip muscles; direct injury or irritation to the pelvis or buttock, which may happen from prolonged sitting on uneven surfaces or objects in the back pocket. Other contributing factors may include differences in leg length and, in rare cases, infection involving the piriformis muscle. Although the condition is relatively uncommon, available studies suggest that females may be slightly more affected with an average age of approximately 44 years. Risk factors include anatomical variations, excessive athletic and lower body activity, prolonged sitting, or susceptibility to trauma. Ways to reduce the risk include proper stretching, muscle strengthening, activity modification, and management of inflammation.

Common signs and symptoms of piriformis syndrome include deep buttock pain or tenderness; pain, numbness, or tingling that radiates down the back of the leg; increased discomfort with prolonged sitting; and worsening pain with movements that activate the piriformis muscle, such as hip rotation and movement of the hip out to the side.

After assessing a patient's symptoms, a health care professional will review the patient's medical history and activity level. A diagnosis of piriformis syndrome requires ruling out other possible sources of nerve compression and pain. For this reason, a thorough physical and neurological examination will be completed to evaluate the lower back, hips, and legs for signs of nerve involvement. If other causes of sciatica are excluded, specific tests may be performed to activate and stretch the piriformis muscle to reproduce symptoms. In some cases where pain is severe, the health care professional may perform a diagnostic injection into the muscle to see if symptoms improve. This can help confirm if the piriformis muscle is the cause. Imaging studies, such as ultrasound or MRI, may be used to evaluate the size of the piriformis muscle or to check other surrounding structures. In summary, piriformis syndrome is a condition in which the piriformis muscle irritates or compresses the sciatic nerve, leading to pain in the buttock and down the leg. Although it can be difficult to diagnose due to overlap with other causes of sciatica, a health care professional can systematically rule out other conditions and develop an appropriate treatment plan based on the patient's symptoms and goals.