Bridging the Gap between Injections and Surgery: Meta-Analysis of Genicular Artery Embolization in Knee Osteoarthritis.

Rationale and objectives: To evaluate the clinical efficacy and safety of genicular artery embolization (GAE) for chronic knee osteoarthritis (OA), incorporating recent trials and long-term outcomes.

Materials and methods: A systematic review identified peer-reviewed studies of GAE in knee OA, including randomized controlled trials (RCTs) and prospective series. Data on pain scores, function, follow-up, and adverse events were extracted. Pooled pain reductions (VAS, WOMAC) were analyzed using random-effects models. Forest and funnel plots visualized treatment effects and publication bias.

Results: Fourteen studies (510 patients, 567 knees) met inclusion criteria, including three sham-controlled RCTs and several prospective series. GAE consistently reduced pain in open-label studies, with a pooled pre-post pain reduction of ∼30 points (0-100 scale) at 6-12 months. Functional scores (WOMAC, KOOS) also improved. About 78-92% of patients achieved clinically meaningful improvement (≥50% pain reduction or ≥10-15 point change) by 12 months. However, sham-controlled RCTs yielded mixed results: one showed early benefit, while two found no significant difference versus placebo at 4-12 months. Heterogeneity was moderate (I² ∼74%). Minor adverse events included transient skin discoloration (∼10-30%) and groin hematoma (∼2-3%). One case of vasculitis and one deep vein thrombosis were reported; no major complications occurred.

Conclusion: GAE appears effective and safe for chronic knee OA, though its benefit over placebo remains uncertain. This meta-analysis, incorporating recent evidence and 2-year data, underscores GAE's promise-but highlights the need for larger, rigorously designed RCTs to confirm efficacy, refine patient selection, optimize techniques, and guide clinical use.