Piriformis syndrome secondary to accessory belly of the piriformis muscle: A rare case report with MRI diagnosis.

Piriformis syndrome refers to rare cause of lower back pain and sciatica caused by abnormal piriformis muscle. Diagnosis is often delayed due to the rarity of the condition, lack of specific clinical symptoms, and physical tests. Only few case reports are reported on the role of magnetic resonance imaging in the diagnosis of piriformis syndrome so far and none are from Ethiopia. Here, we report a case of piriformis syndrome in a 30 years old man who presented with right posterior hip pain that radiates to the thigh and calf. Diagnosis was established using magnetic resonance imaging that showed accessory belly of the right piriformis muscle with sciatic nerve mild thickening. The magnetic resonance imaging findings were consistent with the clinical symptoms, physical examination findings, and electromyography findings.