Piriformis syndrome

Findings

Similar to the hamstring syndrome but no ischial tenderness is palpable. It may be worse with resisted, external rotation of the flexed hip, or passive, internal rotation of the flexed hip.

Cause

The sciatic nerve is compressed between the gemelli or, as a variant, passes through, as opposed to beneath, the piriformis.

Treatment

Adverse neural tensioning and, possibly, a cortisone injection of the piriformis origin at the sacrum may help. Surgery to free the nerve.

Actually, this injury is extremely hard to diagnose. An injection of steroid over the inferior border of the sacrum, close to the notch, may help this type of sciatic pain.

"Concise guide to sports injuries, 2^nd edition",Churchill Livingstone, Malcolm T.F. Read,  foreword by Bryan English