ABSTRACT
STUDY DESIGN: Nineteen of 20 cases that underwent a mono-segment pedicle-screw instrumentation and fusion, following vertebroplasty for lumbar and thoracolumbar fractures, were reviewed retrospectively. OBJECTIVES: To assess the effectiveness of a mono-segment pedicle-screw instrumentation and fusion, following an anterior column reconstruction, using bone cement for a fractured lumbar and thoracolumbar spine. SUMMARY OF LITERATURE REVIEW: With lumbar and thoracolumbar fractures, the untreated anterior instability and pre-stressing of the screws, following reduction, resulted in a high failure rate of the hardware, and posterior screw fixation alone may be not adequate. MATERIALS AND METHODS: We reviewed 19 of 20 cases that underwent a mono-segment pedicle-screw instrumentation and fusion, following vertebroplasty for lumbar and thoracolumbar fractures, between Feb. 2000 and Mar. 2002, with an average follow-up of 1.6 years. The mean age of the patients was 39.2 years, and the male female ratio as 10:9. The criteria for inclusion to the study (McAfee classification) were flexion-distraction injury, burst fracture, translational injury and burst conversion after an osteoporotic compression fracture, in 9, 7, 2 and 2 cases, respectively. We assessed the radiographic results of the local kyphotic angle correction of the fused segment and anterior body height restoration, preoperative, postoperative and at the last follow up, from the lateral views of the spine. The clinical results were evaluated according to Kumano's criteria. RESULTS: The mean local kyphotic angles of the instrumented segment, preoperatively, postoperatively and at the last follow-up were 16.5, 1.1 and 2.1 degrees, with a mean correction gain of 15.4 degrees(p0.05). The mean anterior body heights for each period were 60.4, 89.6 and 85.0%, with a mean restoration gain of 29.2% (p0.05). The clinical results were assessed as good in 18 patients (19 cases) and fair in the other one. There were 3 cases of asymptomatic leakage of the bone cement, but no fixation failures during the follow-up. CONCLUSIONS: A mono-segment pedicle-screw instrumentation and fusion, following the treatment of anterior instability, using vertebroplasty for lumbar and thoracolumbar fractures, can be an effective alternative for preserving the maximal motion segment, without fixation loss through the restoration of the immediate postoperative weight-bearing capability.