Prone Transpsoas Fusion for Grade I - II Symptomatic Degenerative Spondylolisthesis – Prospective Cohort Study of 108 Patients

Study Design Prospective Cohort Study of 108 cases. Objective Prone Transpsoas (PTP) fusion is a minimally invasive surgical technique using a single-position prone lateral approach to augment the anterior column of the lumbar spine. Degenerative spondylolisthesis (DS) is a common pathology where anterior-posterior access can be advantageous. This study aimed to evaluate operative, radiological and functional outcomes of PTP fusion in the management of symptomatic DS. Methods A multi-centre cohort study was conducted, involving 108 consecutive patients who underwent PTP fusion for low-grade (Grade I–II) DS. Descriptive statistical analysis was used to evaluate clinical, radiological and functional outcomes. Results In all 108 cases, anterior column fusion was combined with posterior percutaneous pedicle screw fixation to optimise spinal realignment. The cohort’s average operative time was 115 minutes, and the psoas retraction time was 14 minutes. The cohort had an average slip of 5.9 mm, which was reduced to 0.8 mm ( P < 0.001) postoperatively. Statistically significant radiological improvements were observed in lumbar lordosis (Δ5°), segmental lordosis (Δ4°), anterior disc height (Δ 4.2 mm) and posterior disc height (Δ 2.1 mm). No major vascular or visceral complications were encountered. The sustained neurological complication rate was 1.9%, and patients maintained improved functional outcomes through the 1-year follow-up. Conclusions PTP is a safe approach for managing low-grade DS, showing significant postoperative correction of spinal alignment. These results support the use of PTP fusion for treating spondylolisthesis and add to the growing evidence of its safety and efficacy as a minimally invasive technique.