COMPARATIVE RESULTS BETWEEN OPEN AND MINIMALLY INVASIVE FUSION IN LUMBAR DEGENERATIVE DISEASE

ABSTRACT Objective: Lumbar spine fusion is indicated in patients who are refractory to traditional treatment for degenerative disc disease. The aim of this study was to compare the perioperative and postoperative results of conventional open surgery versus minimally invasive surgery (MIS) in posterior 360° lumbar fusion with pedicle screw instrumentation. Methods: A total of 25 patients underwent MIS and 40 underwent open surgery between 2015 and 2017. Perioperative variables and lumbar and radicular pain values were compared using a visual analogue scale (VAS) and the Oswestry disability index (ODI) until 12 months after surgery. Results: The MIS cohort presented less blood loss (140 vs 345 ml; p=0.001), shorter hospital stay (1.1 vs 2.2 days; p=0.001), longer operative time (113 vs 94 minutes; p=0.001) and greater X-ray exposure (80 vs 6 seconds; p=0.001), compared to the open surgery group. The MIS cohort showed better results in the ODI and lumbar VAS scores. No significant differences were observed in radicular VAS. Conclusion: MIS surgery showed advantages over the open surgery technique; however, the learning curve should be improved in order to reduce operative time. Level of Evidence III; Retrospective descriptive observational study.