Abstract:[Objective] To investigate the clinical efficacy of posterior column osteotomy (PCO) and long-level pedicle screw fixationin the treatment of stage III Kümmell's disease. [Methods] A retrospective analysis was performed on 12 patients who received PCO andlong-segment pedicle scrwe fixation for stage III Kümmell's disease in our department from December 2019 to December 2022. The clini-cal and imaging data were evaluated. [Results] All the 12 patients were successfully operated on without death or serious complicationssuch as nerve injury aggravation, whereas with operation time of (173.6±37.3) min, the intraoperative blood loss of (335.2±67.8) ml, and theincision length of (25.6±3.2) cm. Among them, 2 patients had delirium and another patient had cerebrospinal fluid leakage after operation,and there were no adverse consequences after corresponding treatment. With the passage of time before surgery, 3 months after surgery, and12 months after surgery, the VAS score [(8.7±1.2), (2.1±1.1), (1.9±0.8), P＜0.001], ODI score [(75.7±5.5), (29.7±4.8), (22.4±3.6), P＜0.001]and ASIA neurological function scale [C/D/E, (2/10/0), (1/5/6), (1/5/6), P＜0.001] were significantly improved. In terms of images, the localkyphotic angle [(35.7±5.5)°, (7.1±3.9)°, (7.1±3.5)°, P＜0.001] and anterior vertebral height [(18.5±1.3) mm, (23.8±.2) mm, (23.7±1.3) mm,P＜0.001] were significantly improved over the time period. [Conclusion] The PCO combined with long-segment pedicle screw fixation isan effective surgical method for the treatment of stage III Kümmell's disease.