Effect of intra-knee injection of autologous adipose stem cells or mesenchymal vascular components on short-term outcomes in patients with knee osteoarthritis: an updated meta-analysis of randomized controlled trials

OBJECTIVE: Assess the efficacy of single and multiple intra-articular injections of autologous adipose-derived stem cells (ASCs) and adipose-derived stromal vascular fraction (ADSVF) for the treatment of knee osteoarthritis (OA). METHODS: We conducted a thorough and systematic search of several databases, including PubMed, Embase, Web of Science, Cochrane Library, and ClinicalTrials.gov, to identify relevant studies. The included studies were randomized controlled trials (RCTs) that involved single or multiple intra-articular injections of autologous ASCs or ADSVF for the treatment of patients with knee osteoarthritis, without any additional treatment, and compared to either placebo or hyaluronic acid. RESULTS: A total of seven RCTs were analyzed in this study. The results of the meta-analysis show that compared to the control group, both single and multiple intra-articular injections of ASCs or ADSVF demonstrated superior pain relief in the short term (Z = 3.10; P < 0.0001 and Z = 4.66; P < 0.00001) and significantly improved function (Z = 2.61; P < 0.009 and Z = 2.80; P = 0.005). Furthermore, MRI assessment showed a significant improvement in cartilage condition compared to the control group. (Z = 8.14; P < 0.000001 and Z = 5.58; P < 0.00001). CONCLUSIONS: In conclusion, in osteoarthritis of the knee, single or multiple intra-articular injections of autologous ASCs or ADSVF have shown significant pain improvement and safety in the short term in the absence of adjuvant therapy. Significant improvements in cartilage status were also shown. A larger sample size of randomized controlled trials is needed for direct comparison of the difference in effect between single and multiple injections. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13075-023-03134-3.