Radiological Outcomes of Reduction Surgery for Degenerative Lumbar Spondylolisthesis Using Long Arm Pedicle Screws

Objective: Until now, the spondylolisthesis reduction technique has relied on posterior instrumentation using long arm pedicle screws. In this way, the segments will be brought into alignment with the other vertebrae with the pedicle mats being tightened. The aim of this study is to acknowledge whether reduction surgery for degenerative lumbar spondylolisthesis (DLS) using long arm pedicle screws is able to correct the listhesis and spinopelvic parameters. Methods: We carried out a retrospective study of patients with degenerative lumbar spondylolisthesis who went through reduction surgery using long arm pedicle screws in our institutions from January 2019 to March 2022. Preoperative and postoperative radiological outcomes consisting of listhesis and spinopelvic parameters were assessed. Results: We found a statistical difference between the magnitude of listhesis immediately after surgery and preoperatively (p<0.001), with a successful correction of 85.85%. There was significant decrease in the value of pelvic tilt (p=0.044) and increase in the value of sacral slope (p=0.008) after surgery. Conclusion: Reduction surgery using long arm pedicle screws for DLS was able to reduce the listhesis effectively up to 85.5%, and also to restore the parts of spinopelvic parameters, the pelvic tilt and sacral slope, approaching normal values.