Which nerve passes directly inferior to the piriformis?

• A. Femoral nerve
• B. Obturator nerve
• C. Sciatic nerve
• D. Superior gluteal nerve

Answer: (C)

The nerve that passes directly inferior to the piriformis is the sciatic nerve. The piriformis sits at the pelvic outlet and, in the usual arrangement, the sciatic nerve exits the pelvis through the greater sciatic foramen below the piriformis and then travels down the posterior thigh. This anatomical relationship is a common landmark: superior gluteal nerves run above the piriformis, while the sciatic nerve (often with the inferior gluteal nerve nearby) travels below it. The femoral and obturator nerves have different origins and paths, not exiting the pelvis beneath the piriformis.