A case of posterior element fracture in Kummell's disease.

Kummell's disease is a rare, delayed posttraumatic collapse of a vertebral body that can occur several months or even years after an osteoporotic compression fracture. However, there are few reports of posterior element fractures associated with Kummell's disease. A 72-year-old man who had sustained an L1 osteoporotic compression fracture 14 months prior was admitted to our institution with incapacitating back pain. Plain radiographs showed progressive collapse of the L1 vertebral body and severe kyphosis at the thoracolumbar junction. Magnetic resonance imaging revealed a posterior element fracture as well as osteonecrosis of the L1 vertebral body. An L1 percutaneous vertebroplasty was performed, followed by bone cement-augmented screw fixation to maintain stability and correct the kyphotic deformity. After surgery, pain relief was immediate, and the patient was able to walk unassisted. This case illustrates that continuous axial distraction stress caused by aggravated kyphosis secondary to Kummell's disease may result in posterior element fractures. Our discussion concludes with a literature review.