Abstract
BACKGROUND: Oblique lumbar interbody fusion (OLIF) and posterior lumbar interbody fusion (PLIF) are established techniques for the revision of adjacent segment disease (ASD) following prior lumbar fusion, yet the optimal approach remains controversial. This meta-analysis aimed to compare the clinical, surgical, and radiological outcomes of OLIF versus PLIF in ASD patients. METHODS: A systematic search was performed in PubMed, Embase, Cochrane Library, Web of Science, Scopus, and CNKI without time restriction. Studies comparing OLIF and PLIF for ASD were included. Data were pooled using a random-effects model. Primary outcomes encompassed Visual Analog Scale (VAS) for back/leg pain, Oswestry Disability Index (ODI), operative time, estimated blood loss (EBL), length of hospital stay (LOS), and complication rate. RESULTS: Nine studies (377 patients: 185 OLIF, 192 PLIF) met inclusion criteria. At final follow-up, VAS for low back pain (P = 0.11) and leg pain (P = 0.93), ODI (P = 0.06), and Modified MacNab "excellent/good" rate (P = 0.22) did not differ significantly between OLIF and PLIF groups. OLIF demonstrated significantly greater early postoperative improvements in VAS (P < 0.00001), ODI (P = 0.004) and earlier mobilization (P < 0.0001). Surgically, OLIF was associated with shorter operative time (P < 0.00001), reduced EBL (P < 0.00001), shorter LOS (P < 0.00001), and lower rates of overall complications (P = 0.04), reoperation (P = 0.02), wound infection (P = 0.05) and dural injury (P = 0.005). No significant differences were observed in lumbar plexus injury (P = 0.15) and cage subsidence (P = 0.08). Radiographically, OLIF achieved superior IDH restoration at all time points (P ≤ 0.0009) and better IFH recovery at early and 3-month follow-up (P < 0.00001), whereas differences in IFA (P = 0.93), LL (P = 0.81), and fusion rate (P = 0.93) were not significant. CONCLUSIONS: Both OLIF and PLIF yield comparable long-term functional and fusion outcomes in ASD revision. OLIF, however, offers advantages in early pain relief, reduced surgical invasiveness, faster recovery, and superior disc height restoration, supporting its preferential use in selected patients.