Study design: A prospectively study.
Objective: Our objective was to clarify the safety and efficacy of asymmetrical pedicle subtraction osteotomy (PSO) in the treatment of severe adult lumbar deformities prospectively.
Summary of background data: Vertebral wedge osteotomy provides good correction of kyphosis but has rarely been applied to degenerative lumbar kyphoscoliosis.
Methods: A total of 14 patients who had undergone corrective osteotomy were enrolled. The average age at PSO was 67 years (range, 45-76 yr). The minimum follow-up was 2 years. Patient questionnaires were administered prospectively. Radiographical parameters including sagittal and coronal balance were analyzed.
Results: Average operative time was 310 minutes (range, 254-375 min). Average blood loss was 1090 mL (range, 700-2900 mL).Mean preoperative lumbar lordosis improved from -3° to 42° at the final follow-up, and sagittal balance improved from 12 to 3 cm, respectively. Mean lumbar scoliosis improved from 40° to 12°, and coronal offset improved from 3 to 1 cm, respectively. There was also statistically significant improvement from preoperative to final evaluation in all clinical domains. There were 4 complications: 1 dural tear, 2 hook dislodgements at the cephalad side requiring revision instrumentation, and 1 rod breakage not requiring surgical intervention. Overall, all 14 patients were satisfied with their surgical management and would choose to repeat the procedure.
Conclusion: Our data suggest that the surgical procedure of asymmetrical PSO is to correct the scoliosis, to restore the lumbar lordosis by way of convex-sided posterolateral wedge osteotomy, and may go a long way toward solving the problems of rigid lumbar degenerative kyphoscoliosis.