Intra-articular injection of bone marrow-derived mesenchymal stem cells leading to better clinical outcomes without difference in mri outcomes from baseline in patients with knee osteoarthritis

Purpose: Bone marrow (BM) is frequently used as a source of mesenchymal stem cells (MSCs) because they have a high potential for differentiation. However, it is unclear whether BM-derived MSCs lead to better clinical and magnetic resonance imaging (MRI) outcomes postoperatively. Materials and Methods: This meta-analysis compared the clinical and MRI outcomes in patients with knee osteoarthritis (OA) treated with BM-derived MSCs. Eight studies comparing the clinical and MRI outcomes assessed with various measurement tools in patients with knee OA treated with BM-derived MSCs were included. Results: The range of motion (95% confidence interval [CI], –13.05 to 4.24; p=0.32) and MRI outcomes (95% CI, –0.16 to 1.40; p=0.12) did not differ significantly between the baseline and final follow-up. In contrast, pain (95% CI, 0.89 to 1.87; p<0.001) and functional outcomes (95% CI, 0.70 to 2.07; p<0.001) were significantly improved at the final follow-up when compared to the baseline. Conclusions: This meta-analysis found no significant difference in the tested range of motion and MRI outcomes between the baseline and the final follow-up in patients treated with BM-derived MSCs, whereas significant functional improvement and pain relief were noted when compared with the baseline. Thus, BM-derived MSCs appear to be a viable alternative for patients with knee OA, although long-term and high-quality randomized controlled trials are needed to confirm the clinical benefits.