Spinal epidermoid cyst formation after spinal fracture operation: a case report.

Acquired spinal epidermoid cysts are extremely rare. There are only a few reports on the formation of epidermoid cysts after lumbar puncture or spinal trauma. In this report, we present a patient who was diagnosed with epidermoid cyst after operation for spinal fracture. This 43-year old female suffered from progressively worsening low back pain radiating down the left leg four years after lumbar burst fracture in the L1 segment and subsequent posterior vertebral pedicle screw fixation surgery. 1 year later, the spinal fracture fixation devices were successfully removed. On admission, spinal magnetic resonance imaging found a cyst locating anterior to the site of operation and this lesion was removed by a following total laminectomy. To the best of our knowledge, this is the first case ever reported showing the formation of epidermoid cyst after primary spinal fracture operation. Therefore, in patients with a history of spinal fracture operation, spinal epidermoid cysts should be taken into consideration if the low back pain and radiculopathy were refractory.