Post-operative tension spinal subdural extra-arachnoid hygroma of the lumbar spine: case series, literature review, and recommendations for clinical management.

This is a rare post-lumbar surgery complication that can cause rapidly deteriorating lower limb and sphincteric function. Surgical management with wide durotomy and arachnoid marsupialisation can lead to reversal of neurological deterioration and excellent clinical results. A delayed presentation with pseudomeningocele formation may be managed conservatively if neurology is stable or improving. It is a condition that it is important for the clinician to recognise in order to instigate appropriate management in a time-dependent fashion.