Gluteus maximus calcific tendonosis: a rare cause of sciatic pain.

Extraspinal causes of radicular pain are rare and are in danger of being overlooked. Here, we present a patient with pain radiating into the posterior thigh and lateral calf. Although initial differential diagnosis included lumbar herniated nucleus pulposus, further imaging revealed the presence of gluteus maximus calcific tendonosis. After physical therapy and a potent oral steroid regimen, the pain gradually resolved and the patient was able to return to full activity.