ABSTRACT
<p><b>OBJECTIVE</b>To investigate the surgical outcome of unilateral pedicle screw(UPS) after TLIF technique combined with contralateral percutaneous transfacet screw(PTS) fixation vs bilateral pedicle screws(BPS) fixation in treatment of degenerative lumbar disease.</p><p><b>METHODS</b>From January 2009 to June 2012, 46 patients with degenerative lumbar diseases, including 30 males and 16 females with an average age of 51.5 years old, who were divided into two groups according to different fixation methods. Twenty-two cases underwent UPS after TLIF technique combined with contralateral PTS fixation (group A), while the others underwent BPS fixation(group B). The relative data were analyzed, such as blood loss volume, operative time, fusion rate, ODI score, JOA score and so on.</p><p><b>RESULTS</b>All the patients were followed up for 1 to 3 years with an average of 22 months. Except one case of each group was uncertainty fusion, the rest have obtained bony fusion, and the fusion rates in group A and B were 95.5% and 95.8%, respectively. No displacement and breakage of screw were found during follow-up. Operative time and blood loss volume in group A were better than of group B(<0.05). ODI and JOA scores had improved obviously than preoperation(<0.05), but the differences had no statistical significance between two groups(>0.05).</p><p><b>CONCLUSIONS</b>Two approaches had similar clinical outcomes for degenerative lumbar disease with no severe instability. Compared with BPS fixation, the UPS after TLIF technique and contralateral PTS fixation has the advantages of less trauma, shorter operative time and less blood loss, and it is a safe and feasible surgical technique.</p>
ABSTRACT
STUDY DESIGN: Retrospective study OBJECTIVE: To evaluate the factors affecting metal failure and screw loosening of short-segmental (1- or 2-segmental) monoaxial or polyaxial screw fixation for degenerative lumbar disease. SUMMARY OF LITERATURE REVIEW: There was a report on metal failure and screw loosening in short-segmental monoaxial and polyaxial screw fixation in degenerative lumbar disease. MATERIALS AND METHODS: This study examined 227 cases who underwent short-segmental transpedicular screw fixation and vertebral fusion for a degenerative lumbar. RESULTS: Metal failure of transpedicular screws was detected in 6 cases, 3 each in groups A and B. Screw loosening occurred in 16 and 43 cases in group A and B, respectively. Both groups had a similar incidence of spinal stenosis with instability and spondylolisthesis. The failure rate and screw loosening according to the fusion level was also similar. The failure and screw loosening rates was higher in the cases who did not undergo PLIF than in the cases who underwent PLIF but the difference was not statistically significant. CONCLUSION: The metal failure and screw loosening rates after transpedicular screw fixation and spinal fusion procedures for degenerative lumbar diseases using monoaxial screws and polyaxial screws were similar.