Evaluating the efficacy of intra-articular human amniotic suspension allografts for knee osteoarthritis management: A systematic review and meta-analysis

PURPOSE: Osteoarthritis (OA) is a degenerative joint disease characterized by chronic pain and impaired motor function, posing a significant global health burden. Despite the availability of various treatments to alleviate symptoms, effective long-term management of OA remains a challenge. Recent studies have highlighted the potential role of human amniotic suspension allografts (ASA) in treating knee OA. This study aims to evaluate the efficacy of intra-articular ASA injections for managing knee OA. METHODS: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and the Cochrane handbook, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) and case series examining the efficacy of ASA on knee OA outcomes. We searched the following electronic medical databases: Embase, PubMed, Web of Science, Scopus, and Cochrane Library from inception till March 2024. Studies were included if they involved patients with knee OA, used ASA as the intervention, compared pre- and post-treatment outcomes, and reported knee OA outcome score as the primary outcome with visual analog scale, international knee documentation committee, single assessment numeric evaluation score, and quality of life as secondary outcomes. Data were reported as mean differences (MD) and 95% confidence interval (CI). A p value less than 0.05 was considered statistically significant. RESULTS: Our analysis included 5 studies with a total of 262 patients. ASA injections significantly improved knee OA outcome scores, with an MD of 10.90 points (95% CI: 6.78 to 15.03, p < 0.001). We assessed pain using the visual analog scale and showed a significant reduction with an MD of -35.54 (95% CI: -37.73 to -33.35, p < 0.001). Quality of life showed improvement with an MD of 19.23 (95% CI: 15.03 to 23.42, p < 0.001). The international knee documentation committee sore demonstrated significant improvement with an MD of 28.60 (95% CI: 21.18 to 36.02, p < 0.001). The single assessment numeric evaluation scores also increased significantly, with an MD of 23.84 (95% CI: 18.39 to 29.29, p < 0.001). Lastly, regarding the studies' quality, the 3 RCTs ranged from high quality, with some concerns, to low risk of bias. Additionally, some concerns were identified in 1 non-RCT. The single case series included was assessed as high quality. CONCLUSION: ASA intra-articular injections represent a promising treatment for knee OA, offering significant pain relief and functional benefits. Despite these positive outcomes, further large-scale RCTs with diverse populations are needed to prove the evidence.