Efficacy and Safety of High Tibial Osteotomy Combined with Mesenchymal Stem Cells for Knee Osteoarthritis: A Systematic Review and Meta-Analysis.

This study aimed to systematically review the clinical efficacy of high tibial osteotomy (HTO) combined with mesenchymal stem cells (MSCs) in the treatment of knee osteoarthritis (KOA) and to provide an updated summary of current evidence and identify gaps in knowledge to inform future research directions. The study design is systematic review and meta-analysis. Level of evidence is 3. We searched for clinical controlled studies on the treatment of KOA with HTO combined with MSCs published before May 2026 in databases such as PubMed, Web of Science, the Cochrane Library, and Embase. The literature that met the inclusion criteria was carefully screened, a quality evaluation was conducted, the data information from the literature was extracted, and the data were input into Review Manager 5.4 for meta-analysis. A total of 12 studies involving 714 patients were included. The results of the analysis indicated that the use of HTO combined with MSCs significantly improved the Lysholm score, International Knee Documentation Committee (IKDC) score, Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score, International Cartilage Repair Society (ICRS), Koshino score, and Hospital for Special Surgery (HSS) score. In terms of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the results of the HTO combined with MSCs group were significantly lower. There was no significant difference between the two groups in terms of the visual analog scale (VAS) score, Knee Injury and Osteoarthritis Outcome Score (KOOS), or mechanical axis. No serious adverse events related to stem cell therapy were observed in the included studies. In the treatment of KOA, HTO combined with MSCs appears to be a promising and safe therapeutic strategy. However, owing to the limited number of high-quality RCTs and clinical heterogeneity across studies, current evidence is insufficient to recommend this combination as the standard of care. More robust, properly designed RCTs are needed to confirm its superiority over HTO alone.