Bone Cement Augmentation in the Prevention of Adjacent Segment Failure After Multilevel Adult Deformity Fusion

Study Design: Prospective case report series and detailed description of technique. Objectives: To describe a surgical procedure designed to prevent fracture and cutting-through and pullout of screws in the adjacent segment after multilevel deformity correction in adults. Summary of Background Data: Surgery of adult deformities has a high complication rate. One of the potential late complications is the development of fracture at the first mobile segment above a multilevel lumbar or thoracolumbar spinal fusion that necessitates further surgical intervention with extension of the instrumentation. Augmentation with bone cement of the last instrumented vertebra and the first mobile vertebra has the potential to prevent this pathology. Methods: Three patients with degenerative thoracolumbar kyphoscoliosis and 3 with adjacent segment failure after correction surgery were treated. Cannulated and perforated pedicle screws were placed in the uppermost-instrumented vertebra. A vertebroplasty tube was inserted from 1 side at the center of the first mobile vertebra. Under C-arm control, vertebroplasty was performed in both vertebrae. Results: Intraoperatively, there were no cement-related complications. Follow-ups at 6 and 12 (+/- 2) months revealed there was no loss of correction, fracture or screw loosening in the augmented vertebrae. Conclusions: Bone cement augmentation of the uppermost screws and the first mobile vertebra in multilevel adult deformity and revision surgery seems to be a safe and potentially effective method of preventing adjacent segment failure.