"Window method" in lumbar spinal stenosis surgery: A single-centre retrospective study

ObjectiveThe primary goal of surgery for lumbar spinal stenosis is to achieve adequate neural decompression while preserving spinal stability. This study evaluated the clinical and radiological outcomes of the window technique, which partially preserves the posterior osteoligamentous structures, and assessed its association with postoperative instability and reoperation rates.MethodsThis single-centre retrospective study included 134 patients with lumbar spinal stenosis who underwent decompression exclusively using the window technique. Patients were categorized according to the number of decompressed levels (single-, two-, and three-level). Clinical outcomes included preoperative and postoperative Visual Analog Scale (VAS) leg pain scores and walking distance before the onset of neurogenic claudication. Radiological instability was evaluated using flexion-extension radiographs. Non-parametric statistical tests were used for data analysis.ResultsThe median age of the patients was 64 years, and 73 (54.5%) were female. Decompression was performed at one level in 85 patients, two levels in 32 patients, and three levels in 17 patients. Follow-up exceeded four years in 32.1% of the patients. The mean VAS leg pain score decreased significantly from 7.6 ± 0.9 preoperatively to 2.2 ± 0.9 postoperatively (p < 0.001), although postoperative scores differed significantly among the decompression-level groups (p < 0.001). The mean distance to the onset of neurogenic claudication was 80.2 ± 34.6 m preoperatively, whereas all patients were able to walk more than 500 m without neurogenic claudication at the six-month follow-up. Grade I postoperative iatrogenic spondylolisthesis developed in four patients, three of whom required revision surgery.ConclusionsThe window technique was associated with favorable clinical outcomes and low rates of postoperative instability and reoperation in selected patients with lumbar spinal stenosis without preoperative radiological instability. These findings suggest that the technique may provide adequate neural decompression while preserving postoperative spinal stability in selected patients.