A new type of fracture-dislocation of the thoracolumbar spine.

Ten instances of fracture-dislocation of the thoracolumbar spine are described in which the lower vertebra was displaced forward under the upper one by forward slipping of the posterior articular processes. The mechanism involved is a posterior lumbosacral shearing force. All patients had neurological deficits of different degrees of severity and all but three patients recovered. Surgical treatment was indicated because of instability in four patients and was done in three of the four. Surgical reduction was always difficult. A stable and painless spine was achieved in all patients surveyed, regardless of the kind of treatment given. One patient died of other injuries.