Comparison between Bone Marrow Aspirate Concentrate versus Stromal Vascular Fraction on Osteoarthritis Knee Patients: Meta-Analysis

Background: Osteoarthritis (OA) of the knee is a leading cause of disability, with limited nonoperative treatment options that primarily focus on symptom relief rather than disease modification. Cell-based therapies, including bone marrow aspirate concentrate (BMAC) and stromal vascular fraction (SVF), have emerged as promising alternatives for managing knee OA. However, clinical evidence comparing their efficacy remains limited. Methods: A systematic review and meta-analysis were conducted according to PRISMA guidelines. PubMed, Scopus, and Web of Science databases were searched for clinical studies reporting outcomes after a single intra-articular injection of autologous BMAC or SVF in patients with varying degrees of knee OA. Studies involving adjunct procedures, culture-expanded cells, or multiple injections were excluded. Pain reduction, assessed by the Visual Analog Scale (VAS), and functional improvement, measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), were the primary outcomes. Standardized mean difference (SMD) with 95% confidence intervals (CI) was calculated using a random-effects model. Results: Six studies comprising 261 patients (111 BMAC, 150 SVF) were included. Both treatments resulted in significant improvement in pain and function. BMAC reduced mean VAS from 4.5 ± 1.27 to 1.71 ± 0.82 (SMD 2.609; 95% CI, 1.781–3.436), while SVF reduced VAS from 6.1 ± 1.1 to 3.3 ± 1.5 (SMD 3.470; 95% CI, 1.175–5.765). SVF showed significantly greater pain reduction compared with BMAC (P < 0.0001). Both BMAC (SMD 1.403; 95% CI, 0.385–2.421) and SVF (SMD 1.125; 95% CI, 0.497–1.754) demonstrated equivalent functional improvement according to WOMAC scores (P = 0.626). Study heterogeneity and methodological inconsistencies were noted, particularly in cell preparation and reporting standards. Conclusion: A single injection of either BMAC or SVF provides short-term symptomatic relief in knee OA. SVF appears superior to BMAC for pain reduction, while both are equally effective in improving function. Given the heterogeneity of preparation protocols and limited high-quality evidence, results should be interpreted with caution. Further standardized, large-scale randomized controlled trials are needed to establish definitive recommendations. Keywords: Knee osteoarthritis; Bone marrow aspirate concentrate; Stromal vascular fraction; Cell-based therapy