Introduction: As spinal fusions become more common and more complex, so do the sequelae of these procedures, some of which remain little understood. The authors report on a series of patients who underwent removal of hardware after CT-proven solid fusion, confirmed by intraoperative findings, who went on to develop a spontaneous fracture of the fusion mass, not associated with trauma.
Methods: A retrospective review of the surgical logs of three, fellowship-trained spine surgeons from the West Virginia University Department of Orthopaedics yielded 7 patients with fracture of a fusion mass after hardware removal. Patient demographics and comorbidities, initial indication for surgery, number of total surgeries, timeline of fracture occurrence, risk factors for fracture, as well as sagittal imbalance were recorded.
Results: All 7 patients underwent hardware removal in conjunction with an extension of fusion for adjacent segment disease across multiple levels. All had CT-proven solid fusion of their previously fused segments, which was confirmed intraoperatively. All patients had multiple previous operations for a variety of indications. Four patients were smokers. Three patients had osteoporosis. Spontaneous fracture of the fusion mass occurred without history of trauma in all patients. These occurred 4 months to 4 years after hardware removal. All patients had significant sagittal imbalance of 13-15 cm. The most common fracture level was L5 in six of the patients.
Conclusions: Based upon our case series, the development of a spontaneous fracture of the fusion mass may be related to sagittal imbalance and consideration should be given to re-implanting hardware for these patients, even across good fusions, to prevent spontaneous fracture of these areas if the sagittal imbalance is not corrected.
Patient Care: unique complication after removal of hardware in patients with severe sagittal imbalance
Learning Objectives: By the conclusion of this session, participants should be able to 1) discuss a possible implication of hardware removal in the face of large sagittal imbalance.