Does Minimally Invasive TLIF Reduce Adjacent Segment Disease and Reoperation Rates Compared With Open TLIF? A Meta-analysis

Objective: To determine whether minimally invasive-TLIF(MI-TLIF) reduces the rates of adjacent segment disease (ASD) and reoperation compared with open TLIF/PLIF (O-TLIF). Summary of background data: O-TLIF is a well-established procedure for degenerative lumbar spine disorders but is associated with extensive soft-tissue disruption, increased blood loss, and prolonged recovery. MIS-TLIF aims to reduce perioperative morbidity, yet its long-term impact on ASD and reoperation remains debated. Methods: A systematic search of PubMed, Cochrane Library, Scopus, Embase, Web of Science, and Google Scholar was conducted for studies published from January 2000 to June 2024. Eligible studies were longitudinal comparative designs comparing adults undergoing MI-TLIF versus O-TLIF with ≥24-month follow-up and reporting adjacent segment disease (ASD) rates. Primary outcome was ASD; whereas secondary outcomes included rate of reoperation, pseudarthrosis, and patient-reported outcomes. Random-effects meta-analyses were performed using odds ratios (ORs) with 95% confidence intervals (CIs). Multivariate meta-regression assessed the influence of age, BMI, fusion level, follow-up duration, and smoking status. Risk of bias was evaluated using ROBINS-I, and certainty of evidence was graded with GRADE. The study followes PRISMA guidelines and was registerd with PROSPERO. Publication bias was evaluated with funnel plots and the Egger test. Results: Fourteen studies met the inclusion criteria, encompassing 1960 patients: 909 in the MI-TLIF group and 1051 in O-TLIF group. were included. All 14 included studies were observational, 12 were retrospective, and two were prospective.MIS-TLIF reduced the odds of ASD (OR 0.51, 95% CI: 0.37–0.69; P <0.001) and reoperation (OR 0.53, 95% CI: 0.31–0.90; P =0.018) compared to O-TLIF,with low heterogeneity. Both procedures showed comparable rates of pseudoarthrosis (OR 0.96, 95% CI: 0.38–2.48; P =0.94) and comparable degree of improvement in the patients reported outcome measures. Multivariate meta-regression identified multiple-level fusion as increasing ASD risk ( P =0.002) and older age as protective ( P =0.002). BMI, smoking, and follow-up duration were not significant predictors. No publication bias was detected. Of the 14 included studies, three were judged to have a low risk of bias, seven a moderate risk, three a serious risk, and one a critical risk of bias due to confounding. Conclusions: MI-TLIF offers a lower risk of ASD and reoperation compared with O-TLIF/PLIF, with comparable fusion outcomes and the improvement in the patient-reported outcome measures. The number of levels fused, l, and patient age are important predictors of ASD. The study concludes an advantage for MI-TLIF over OTLIF regarding long-term outcome measures, especially ASD rate and re-operation rate. However, this should be viewed in the context of the retrospective observational design of the included studies.