Herniation of a broad ligament dermoid cyst through sciatic foramen--a rare cause of gluteal swelling

A 35-year-old lady presented with a slowly growing lump in her left buttock. Examination revealed a soft, partly reducible swelling having expansile impulse on coughing. CT scan and real time ultrasound showed it to be an extension of intrapelvic cystic space occupying lesion. At laparotomy, the cyst was found to be arising in between two layers of broad ligament and leaving the pelvis through greater sciatic foramen. Contents of the cyst were cheesy material and hair. Histopathological examination of the cyst wall confirmed the diagnosis. As such, sciatic hernia is a very rare surgical entity. Over and above, herniation of a dermoid cyst arising in the broad ligament is also an equally rare event.