Pain in the butt is a commonly used idiom, but it actually can be a real pain to many as piriformis syndrome. It is commonly seen in people who spend long hours sitting, such as desk bound jobs, long distance driving or riding a motor bike. Many long distance runners, cyclists, and skiers are at a high risk of getting Piriformis Syndrome as well. Symptoms are usually unilateral and are present as pain in the buttock or hamstring area. Affected side may experience neurogenic (nerve related) symptoms such as pins and needles, loss of sensation and weakness down the limb. Symptoms generally get worse with sitting or activities involving running. Many patients also report a feeling of a pebble under the affected buttock while sitting.
Piriformis muscle is found deep under the big gluteal muscles. It runs across the pelvis area outwards and attaches to the femur (thigh bone). It serves as a rotator of the hip joint. It is an external rotator when the hip is extended and an internal rotator when the hip is flexed. Piriformis is very closely related to the sciatic nerve which runs down the leg from the lower back area. Piriformis muscle sits across and over sciatic nerve. In certain people, the sciatic nerve actually passes through the piriformis muscle itself. Any injury, irritation or tightness to the muscle may irritate the sciatic nerve and lead to neurogenic symptoms down the limb.
- Injury to the muscle – from a fall
- Limb length discrepancy
- Jobs involving prolonged sitting
- Poor sporting technique
- Muscle imbalance around Lumbopelvic area (lower back and pelvis)
- Piriformis compensating for weak gluteal muscles
- Tight hip flexors and adductors
- Overpronation(flattening) of foot – causing internal rotation at hip
- Altered gait biomechanics
- Any pyogenic infection