Hyperextension injuries of the thoracic spine in diffuse idiopathic skeletal hyperostosis. Report of four cases.

Four patients who had multisegmental ankylosis of the thoracic and lumbar spine due to diffuse idiopathic skeletal hyperostosis sustained a hyperextension fracture-dislocation. The patients had a mean age of sixty-four years (range, fifty-eight to sixty-nine years); all four patients were men. All injuries occurred between the seventh and eleventh thoracic vertebrae. All patients had intact neurological function at the time of admission to the hospital. Three patients were managed with posterior spinal arthrodesis with Cotrel-Dubousset segmental instrumentation; one patient was managed non-operatively with a molded thoracolumbosacral orthosis. At a minimum duration of follow-up of twenty-two months (mean, twenty-seven months), the three patients who had been managed operatively had healing of the fracture with anatomical alignment of the spine and without postoperative complications. The one patient who had been managed non-operatively with a brace had severe neurological deterioration and non-anatomical alignment of the spine.