Minimally Invasive SI Joint Fusion Improves Pain and Disability With Low Reoperation Rates

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: To conduct a meta-analysis of high-level prospective evidence studies evaluating changes in Visual Analogue Scale (VAS), SI joint pain scores, Oswestry Disability Index (ODI) outcomes, and adverse events (SAE) requiring an additional operation. SUMMARY OF BACKGROUND DATA: Low back pain is a leading cause of disability, and the sacroiliac joint (SIJ) is implicated as a primary pain generator in up to 25% of cases. However, SIJ-mediated pain is difficult to diagnose, and is often one of exclusion confirmed by diagnostic injections. Minimally invasive SIJ fusion has emerged as a treatment option for patients with confirmed SIJ dysfunction who fail nonoperative care. METHODS: A systematic review and meta-analysis were performed according to PRISMA guidelines. Eleven studies (9 prospective cohort and 2 randomized control trials) met inclusion criteria based on study design, quality of evidence, and reporting of patient-reported outcomes. Demographic data, baseline characteristics, surgical indications, and outcomes were extracted. Meta-analyses were conducted to calculate pooled estimates of VAS and ODI improvements, and reoperation rates. RESULTS: Eleven studies reporting on 1,181 sacroiliac joint fusions were included, with a mean follow-up of 27.8 months. Sacroiliac joint pathology was confirmed by diagnostic SIJ injection in 92.7% of patients. Meta-analysis showed a VAS improvement of 45.5 points (95% CI: 38.6-52.3) and an ODI improvement of 23.3 points (95% CI: 21.0-25.7), both exceeding established MCID thresholds (P < 0.001). The meta-analysis of reoperation rates for implant-related serious adverse events was 3% (95% CI: 2%-4%). CONCLUSION: Minimally invasive SIJ fusion, performed across multiple implant systems and surgical techniques, yields large, clinically meaningful, and reproducible improvements in pain and disability with a low reoperation rate. Outcomes are most favorable when patient selection is rigorous and SIJ dysfunction is accurately identified as the primary pain generator using diagnostic SIJ injection, underscoring the importance of standardized diagnostic pathways in optimizing surgical benefit.