Thoracic disc herniation: An unusual complication after prone positioning in spinal surgery.

Neurological complications of the prone position have been well documented. Post-operative paraplegia and neurological deterioration unrelated to the site of surgery after proning in spinal surgery is a rare but potentially devastating complication. We describe the case of a 47 year old female who underwent an L4/5 discectomy and posterior instrumented fusion. A few hours after surgery she developed bilateral lower limb weakness with a T11 sensory level. Post-operative MRI revealed an acute disc herniation at the T11/12 level with associated spinal cord compression. This was not present on the pre-operative imaging. A subsequent T11/12 discectomy and instrumented fusion was performed and the patient's motor and sensory function returned to normal.