Résumé
Objective To evaluate the effects of posterior segmental pedicle screw instrumentation and augmentation using calcium sulphate cement in treatment of Denis type B thoracolumbar burst fractures.Methods Forty patients with Denis type B thoracolumbar burst fracture treated between January 2011 and December 2012 were reviewed retrospectively.Twenty patients received posterior short-segment pedicle screw fixation in conjunction with screw placement at the level of fracture and calcium sulphate augmentation without posterolateral fusion (combined treatment group),but 20 patients underwent traditional short-segment pedicle screw fixation (conventional treatment group).Radiographs and CT scans evaluated local kyphotic angle on the spot of injury,anterior height of the injured vertebra,and canal encroachment before and after operation and at final follow-up.Meanwhile,visual analogue score (VAS),Oswestry disability index (ODI),and neurologic status based upon ASIA 2000 were assessed.Results Mean follow-up period was 15 months (range,12-24 months).Vertebral height restoration was equivalent of the two groups immediately after operation,but better result of kyphosis correction was found in treatment group than in control group (P ＜ 0.05).Anterior vertebral height and kyphotic angle significantly improved in treatment group compared to control group at final follow-up (P ＜ 0.05).Clinical and neurologic outcome evaluation were similar between the two groups.No implant failure occurred at follow-up.Conclusion For Denis type B thoracolumbar burst fractures,posterior segmental pedicle screw fixation augmented with calcium sulphate is effective for reducing correction loss and implant failure,compensating for the deficiencies of conventional fixation.