Cartilage Regeneration Potential in Early Osteoarthritis of the Knee: A Prospective, Randomized, Open, and Blinded Endpoint Study Comparing Adipose-Derived Mesenchymal Stem Cell (ADSC) Therapy Versus Hyaluronic Acid.

Early-stage knee osteoarthritis (knee OA) lacks effective regenerative therapies. This study aimed to compare the cartilage regenerative effects, clinical efficacy, and safety of intra-articular injections of autologous adipose-derived mesenchymal stem cells (ADSCs) versus hyaluronic acid (HA). Forty-eight patients with early knee OA were enrolled in a prospective open-blinded multi-center study at Suranaree University of Technology Hospital and Phramongkutklao Hospital. Participants were randomized into either the ADSC or HA group. Primary outcomes included MRI-based cartilage lesion volume, synovial thickness via ultrasound, and WOMAC scores over 6 months. MRI results revealed significant and progressive cartilage regeneration in the ADSC group. In particular, medial femoral cartilage lesion volume decreased by 50.06 mm3, whereas the HA group showed an increase of 36.44 mm3. Synovial thickness also declined significantly in the ADSC group at 3 and 6 months. Both groups demonstrated reduced symptoms, but the ADSC group achieved superior and sustained improvements in WOMAC pain, stiffness, and function scores throughout the 6-month follow-up. The clinical benefits were consistent and more pronounced compared with HA. No serious adverse events occurred. In conclusion, intra-articular ADSC injections show superior cartilage restoration on MRI and better clinical outcomes than HA injection, making them a promising treatment for early-stage knee OA.