Autologous minimally manipulated adipose-derived stromal vascular fraction in knee osteoarthritis: Lasting symptom relief and imaging evidence from a 12-month prospective study

Purpose: To evaluate the safety and efficacy of intra-articular autologous transplantation of adipose-derived connective tissue micrografts rich in stromal vascular fraction (CTM-SVF), obtained using an enzyme-free system (Hy-Tissue® SVF) for knee osteoarthritis (OA). Methods: Thirty patients (mean age of 53.3 ± 6.4 years) with Kellgren-Lawrence grade I to III knee OA received a single intra-articular injection of autologous CTM-SVF prepared with the Hy-Tissue SVF concentration system. Follow-ups were set at 3-, 6- and 12-month postinjection. Outcome measures included knee injury and osteoarthritis outcome score (KOOS), pain relief (NRS-11), quality of life (EQ-5D index), magnetic resonance imaging (MRI) scans (whole-organ magnetic resonance imaging score-WORMS, T2 mapping), OA serum biomarkers, safety and local tolerability. Results: One patient discontinued prematurely. KOOS improved significantly, with the highest mean score (68.7 ± 14.9) at 3 months and the majority of patients achieving a ≥ 9-point increase from baseline. Results were maintained through 12 months. NRS-11 and EQ-5D also improved through 12 months, with more than 80% of patients meeting the NRS-11 MCID at every timepoint. EQ-VAS, however, showed only a modest responder rate (10%). MRI revealed improvements in T2 relaxation times, while OA serum biomarkers (evaluated at 3 months postinjection) indicated a significant decrease in Procollagen II N-Terminal Propeptide levels. No device-related adverse events (ADEs) were observed. The majority of adverse events (AEs) recorded during the study were mild and transient, none were classified as serious and resolved within a short period. Conclusions: Intra-articular injection of autologous CTM-SVF, obtained the Hy-Tissue-SVF system, proved to be effective and safe for managing knee OA symptoms and improving mobility, up to 12 months. Clinically significant pain relief and quality of life improvement were observed, particularly in the short term, with a gentle reduction of the scores over time. Larger controlled trials are required to confirm treatment durability. Level of evidence: Level II.