Microfragmented Adipose Tissue as an Alternative to Platelet-Rich Plasma for Intra-articular Injection in Knee Osteoarthritis: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Background: Intra-articular (IA) injections of orthobiologics, such as platelet-rich plasma (PRP) and microfragmented adipose tissue (MFAT), have recently gained attention as treatments for knee osteoarthritis (OA). However, clinical evidence supporting their use remains limited. Purpose: To evaluate the effectiveness and safety of IA injections of PRP and MFAT in patients with knee OA and to compare these 2 treatment modalities. Study Design: Systematic review and meta-analysis; Level of evidence, 2. Methods: A systematic search was conducted in the MEDLINE, Embase, and Cochrane Library databases to identify randomized controlled trials assessing the efficacy and safety of PRP or MFAT injections in knee OA. Outcomes included pain relief (measured by the 100-mm visual analog scale), functional improvement (assessed by the Knee injury and Osteoarthritis Outcome Score and International Knee Documentation Committee subjective score), and safety (assessed by procedure-related adverse events). The minimal clinically important difference was used to evaluate the clinical significance of the treatments, and a meta-analysis was performed to compare PRP and MFAT. Methodological quality was assessed using the Modified Coleman Methodology Score. Results: Six randomized controlled trials were included in the analysis. Both PRP and MFAT achieved minimal clinically important difference in most clinical outcomes up to 12 months after injection. The meta-analysis revealed comparable results for pain relief, functional improvement, and safety between the MFAT and PRP groups from 1 to 24 months after treatment. However, at the 6-month mark, MFAT demonstrated a small but statistically significant advantage over PRP in most clinical outcomes. The median Modified Coleman Methodology Score was 73 (range, 70-75). Conclusion: IA injections of PRP and MFAT both provided significant clinical benefits and were safe for treating knee OA over a 12-month period. Although no substantial differences were observed between the 2 treatments in most follow-up periods, MFAT showed slightly better pain relief and functional improvement at 6 months. However, further research is needed to confirm these findings and guide clinical practice.