Minimally Invasive Transforaminal Lumbar Interbody Fusion in Multilevel: Comparison with Conventional Transforaminal Interbody Fusion

OBJECTIVE: Minimally invasive (MIS) transforaminal lumbar interbody fusion (TLIF) has shown superior or noninferior results compared with conventional TLIF in single segments. There were no comparative studies between MIS and conventional TLIF in multisegments. The purpose of this study was to compare MIS and conventional TLIF in multisegments. METHODS: This is a cross-sectional study of 2- or 3- segment lumbar degenerative disease that was treated with either MIS (27 cases) or conventional TLIF (43 cases). Whole spine sagittal radiography was done preoperatively and 1 year after surgery. Clinical outcomes, perioperative outcomes, and fusion rate were compared. Radiologic parameters, such as cervical lordosis, thoracic kyphosis, lumbar lordosis, sagittal vertical axis, and pelvic parameters, were measured 1 year after surger. RESULTS: The two groups were similar in age, sex, pre-operative diagnosis, operated level, and follow-up period. Both groups showed improvement in visual analog scale and Oswestry disability index after surgery. The MIS TILF group had a significantly shorter operation time (167.10 vs. 216.58 minutes) and less blood loss (532.41 vs. 865.81 mL). Only cervical lordosis (MIS TLIF, -17.2 degrees; conventional TLIF, -11.2 degrees) was significantly different preoperatively between the groups. Postoperatively, there were no significant differences in radiologic parameter and fusion rate. In the intragroup comparisons, thoracic kyphosis, lumbar lordosis, and sacral slope were significantly increased and pelvic tilt was significantly decreased after surgery. CONCLUSIONS: MIS TLIF and conventional TLIF showed similar clinical and radiologic outcomes. MIS TLIF may be a better choice for 2- or 3- segment lumbar fusion in perioperative outcomes.