Transdiscal Screw Fixation in L5-S1 Adult Spondylolisthesis: Technical Note and Midterm Outcomes of a Case Series

Spondylolisthesis changes the pelvic morphology and sagittal spinopelvic alignment with abnormality compared to individuals with similar pelvic morphology. There are many treatment options including a combination of decompression and fusion. In spondylolisthesis patients with high-grade spondylolisthesis, bone to bone contact (closed intradiscal space), and high-grade disc degeneration with disc collapse, fusion is challenging.

From 2011 through 2020, an analysis of L5-S1 spondylolisthesis patients who had L5-S1 transdiscal screw fixation with a minimum follow-up of 2 years was performed. Radiological evaluation and clinical measures were compared preoperatively and postoperatively. Postoperative complications were analyzed. Also, L5-S1 degree fusion was analyzed using a computed tomography scan.

Eight patients of L5-S1 spondylolisthesis with a mean follow-up of 69 (25-122) months. All patients were female; the average age was 58 (43-78) years. 4 patients presented with high-grade spondylolisthesis (Meyerding grade III). Among the patients, 3 patients were undergoing revision surgery. Only 5 patients had interbody fusion for their adjacent levels. In the postoperative follow-up, none of the patients had neurological deficits. Radiological evaluations of L5-S1 level showed fusion in all patients. Only 1 patient had rod failure and was advised for revision surgery.

L5-S1 transdiscal screw fixation may provide a satisfactory rigid fixation and fusion at the L5-S1 level in cases of spondylolisthesis. This technique requires a surgeon's experience. Despite the challenge of this technique, it can provide a safe option for acquiring rigid stabilization.