Spinal subdural hygroma as a post-operative complication in revision spine fusion: a case report.

Lumbar spine fusion has become a common and effective procedure in orthopedic practice, and a spinal subdural hygroma development is a rare complication following this procedure. We report here the case of a revision lumbar spine fusion at levels L4-5, L5-S1, where the patient subsequently developed cauda equina syndrome 2 days post-operatively. Magnetic resonance imaging (MRI) showed a subdural, extra-arachnoid fluid collection from T12-L2, cephalad to the site of spine fusion. It appears the first case reported a subdural hygroma developed cephalad to the site of spine fusion. When a patient complains of radicular pain along with urinary retention and neurologic deficits post-lumbar spine surgery, cauda equina syndrome possibly caused by subdural hygroma should be considered. This warrants immediate MRI and emergent reoperation to relieve the pressure on the spinal cord may be necessary.