Clinical and radiological outcomes of modified mini-open and open transforaminal lumbar interbody fusion: A comparative study

Abstract

Study Design: Retrospective cohort study. Purpose: To compare the clinical and radiological outcomes of modified mini-open transforaminal lumbar interbody fusion (modMOTLIF) and open TLIF (OTLIF). Overview of Literature: Minimally invasive transforaminal lumbar interbody fusion (MTLIF) is associated with less blood loss, shorter hospital stay, and less pain. However, it has concerns like increased radiation exposure, steep learning curve, and instrumentation cost. We modified the MTLIF technique by direct freehand insertion of pedicle screws using stab incisions without tubular retractors. Methods: The study included 24 patients in the modMOTLIF group and 27 patients in the OTLIF group. The average follow-up period was 25.6 months. Clinical outcomes were measured using Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) scores. Serial X-rays were acquired at 1, 3, 6, 12, and 24 months to assess the union and presence of instability. We also compared blood loss and length of hospital stay in both groups. Results: All patients showed progressive improvement in VAS and ODI scores. No differences were observed in the preoperative and postoperative ODI and VAS leg scores between the groups. The immediate postoperative VAS back score was significantly higher in the OTLIF group than in the modMOTLIF group; however, no difference was observed at 1 and 2 years. Radiological analysis showed nonunion in one and two patients in the OTLIF and modMOTLIF groups, respectively. The average blood loss was 63 mL in the mod- MOTLIF group and 254 mL in the OTLIF group. The mean hospital stay was 3 days for the modMOTLIF group and 5 days for the OTLIF group. Conclusions: modMOTLIF was associated with reduced blood loss and shorter hospital stay compared with OTLIF. No significant differences were observed in the clinical and radiological outcomes between the groups after 2 years despite reduced back pain in the immediate postoperative period in patients who underwent modMOTLIF.