Compression fracture in the middle of a chronic instrumented fusion that developed into pseudarthrosis after balloon kyphoplasty.

There are only 2 documented cases of vertebral compression fractures occurring within a solid lumbar fusion mass: one within the fusion mass after hardware removal and the other within the levels of the existing instrumentation 1 year postoperatively. The authors report a case of fracture occurring in a chronic (> 30 years) solid instrumented fusion mass in a patient who underwent kyphoplasty. The pain did not improve after the kyphoplasty procedure, and the patient developed a posterior cleft in the fusion mass postoperatively. The patient, a 46-year-old woman, had undergone a T4-L4 instrumented fusion with placement of a Harrington rod when she was 12 years old. Adjacent-segment breakdown developed, and her fusion was extended to the pelvis, with pedicle screws placed up to L-3 to capture the existing fusion mass. Almost 2 years after fusion extension, she fell down the stairs and suffered an L-2 compression fracture, which is when kyphoplasty was performed without pain relief, and she then developed a cleft in the posterior fusion mass that was previously intact. She refused further surgical options. This case report is meant to alert surgeons of this possibility and allow them to consider the rare occurrence of fracture within the fusion mass when planning extension of chronic spinal fusions.