Microendoscopy-Assisted Minimally Invasive Versus Open Transforaminal Lumbar Interbody Fusion for Lumbar Degenerative Diseases: 5-Year Outcomes

OBJECTIVE: We sought to evaluate 5-year outcomes between microendoscopy-assisted minimally invasive (MIS) and open transforaminal lumbar interbody fusion (TLIF). METHODS: Sixty single-level MIS and open surgeries were performed (30 patients in either group). Perioperative parameters including operative duration, intraoperative estimated blood loss, fluoroscopy time, postoperative analgesic usage, ambulatory time, and complications were recorded. Visual analog scale (back and leg), Japanese Orthopaedics Association score, and Oswestry Disability Index were obtained. Finally, self-evaluation of surgical outcomes (modified MacNab criteria), interbody fusion rate (Bridwell grade 1), and prevalence of adjacent segment degeneration were assessed. RESULTS: Intraoperative estimated blood loss and postoperative analgesia usage were reduced in the MIS group, and patients undergoing microendoscopy-assisted MIS-TLIF ambulated earlier than those receiving open TLIF postoperatively. Nevertheless, surgical duration and fluoroscopy time were prolonged in the MIS group. Complication incidences were similar in both groups. Visual analog scale (back and leg), Japanese Orthopaedics Association, and Oswestry Disability Index were improved at 1 month, 2 years, and 5 years postoperatively in both groups when compared with preoperative scores. Significant improvements in these scores were found in the MIS group at 1 month postoperatively, while at 2 years and 5 years postoperatively, both groups revealed comparable aforementioned scores. Excellent and perfect scale rating, interbody fusion rate, and adjacent segment degeneration prevalence between the groups were almost similar. CONCLUSIONS: Microendoscopy-assisted MIS-TLIF is comparable with open TLIF in terms of 5-year outcomes with additional benefits of reduced intraoperative iatrogenic injury, decreased initial pain, minimized activity restrictions, and accelerated ambulation recovery after surgery.