Thoracic hyperextension injury with opening wedge distraction fracture in DISH -consideration of surgical strategy based on intraoperative pathological findings-

Diffuse idiopathic skeletal hyperostosis (DISH) is a well-recognized disease characterized by calcifications and ossifications of the entheses mainly in the spine. Patients with DISH are prone to sustaining spinal injuries even after minor trauma because of the long-lever arm mechanism induced by any type of force acting on the rigid yet brittle spine. The number of cases of trauma in DISH-affected spines is predicted to increase during the coming decades because of an increase in DISH-related comorbidities. Generally, posterior fixation with spinal instrumentation spanning three levels above and below the injured site is regarded as a standard treatment for hyperextension fractures of the thoracolumbar spine in patients with DISH. However, no consensus has been reached regarding whether additional anterior fixation is needed for hyperextension injuries with remarkable vertebral body wedge. We experienced one case of hyperextension injury at the thoracic level in patient with DISH. A remarkable remodeling phenomenon in the fractured vertebral body was intraoperatively noticed, which was pathologically confirmed. This is the first report to have confirmed pathologically new bone formation in the anterior column wedge despite the fact that only 1 month had passed since the first injury. Although whether additional anterior fixation is needed for hyperextension injuries with remarkable vertebral body wedge is controversial, this report supports that posterior fixation alone might be an adequate treatment.