Post-traumatic lumbar nerve root avulsion.

Lumbar nerve root avulsion is a rarely seen clinical entity that may complicate major trauma. The majority of previously reported cases have associated pelvic or lumbar vertebral fractures. Two cases of traumatic pseudomeningoceles at the lumbar level with associated avulsions of the lumbar nerve roots are presented. Both patients were involved in high velocity motor vehicle accidents. Case 1 had associated pelvic fractures but no spinal fractures and, interestingly, case 2 had no fractures of the spine or pelvis. The value of MRI in making the diagnosis is demonstrated.