SURGICAL TREATMENT OF SPONDYLOLYSIS OF THE LUMBAR SPINE - A SIGNIFICANCE OF PEDICULAR SCREW AND SEGMENTAL WIRE FIXATION OF THE PARS DEFECTS

The purpose of this study was to determine the significance of pedicular screw and segmental wire fixation for the treatment of spondylolysis. Twenty-five patients of spondylolysis were treated operatively. Seventeen patients of them had isthmic sondylolisthesis with an average displacement of 22% (ranges, 4–55%). Thirteen patients (6 patients had spondylolisthesis) were treated by the direct repair of the pars defect with bone graft with pedicular screw and wire fixation methods (Group A), and 12 patients (11 patients had spondylolisthesis) were treated by posterior lumbar interbody fusion or postero-lateral fusion (Group B). The mean age at the operation was 34 in the former, and 45 in the latter. The average volume of bleeding was 291ml in Group A and 840ml in Group B. Operative results were evaluated as excellent, good, fair and poor by Henderson’s evaluation of functional capacity. Radiographically, bony fusion rate was examined. The average follow-up period was 33 months. At the final follow-up stage, clinical outcome was excellent in 5 patients, good in 7, fair in 1, and poor in zero in Group A, and that was in 8,3,0, and one in Group B. Nerve roots irritation was observed in one patient in Group B postoperatively. Bony fusion rate was 100% in both groups. However, delayed union was observed in 2 cases of the Group A. The range of motion L5/sacrum increased to 10 degree from 9 degree (p=0.1) Spondylolysis with severe low back pain has been treated by major surgery like spondylodesis. This study showed that the direct repair of the pars defects is the acceptable methods for the treatment of spondylolysis either no or minimal spondylolisthesis.