The Clinical and Radiological Outcomes of Minimally Invasive Transforaminal Lumbar Interbody Single Level Fusion

STUDY DESIGN This is a retrospective study that was done according to clinical and radiological evaluation. PURPOSE We analyzed the clinical and radiological outcomes of minimally invasive transforaminal lumbar interbody single level fusion. OVERVIEW OF LITERATURE Minimally invasive transforaminal lumbar interbody fusion is effective surgical method for treating degenerative lumbar disease. METHODS The study was conducted on 56 patients who were available for longer than 2 years (range, 24 to 45 months) follow-up after undergoing minimally invasive transforminal lumbar interbody single level fusion. Clinical evaluation was performed by the analysis of the visual analogue scale (VAS) score and the Oswestry Disability Index (ODI) and the Kirkaldy-Willis score. For the radiological evaluation, the disc space height, the segmental lumbar lordotic angle and the whole lumbar lordotic angle were analyzed. At the final follow-up after operation, the fusion rate was analyzed according to Bridwell's anterior fusion grade. RESULTS For the evaluation of clinical outcomes, the VAS score was reduced from an average of 6.7 prior to surgery to an average of 1.8 at the final follow-up. The ODI was decreased from an average of 36.5 prior to surgery to an average of 12.8 at the final follow-up. In regard to the clinical outcomes evaluated by the Kirkaldy-Willis score, better than good results were obtained in 52 cases (92.9%). For the radiological evaluation, the disc space height (p = 0.002), and the whole lumbar lordotic angle (p = 0.001) were increased at the final follow-up. At the final follow-up, regarding the interbody fusion, radiological union was obtained in 54 cases (95.4%). CONCLUSIONS We think that if surgeons become familiar with the surgical techniques, this is a useful method for minimally invasive spinal surgery.