[Primary sacral epidural hydatid cyst: a case report].

Primary epidural hydatid cyst of the spinal canal without bone involvement is very rare. The authors report the case of a 35 year old man presenting with lower cauda equina compression. MRI showed a cystic lesion with signal characteristics similar to cerebrospinal fluid. Surgical exploration through a midline posterior approach was used which confirmed the hydatid nature of the cyst. There was no bone lesion. Histological examination confirmed the diagnosis. Hydatid cyst should be suspected in case of cystic lesion causing cord compression or cauda equina syndrome.