Ultrasound-guided intra-articular injection of expanded umbilical cord mesenchymal stem cells in knee osteoarthritis: a safety/efficacy study with MRI data.

This study has the primary objective of studying the effect of Wharton jelly mesenchymal stem cells (WJMSCs) in the treatment of knee osteoarthritis. As a secondary end point, we report on the efficacy of such therapy. 16 patients with advanced Kellgren stage were treated using two doses of expanded WJMSCs given 1 month apart. Patients were followed for 48 months using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and 12 months using magnetic resonance imaging (MRI). Treatment was well tolerated. One patient developed moderate effusion and one superficial phlebitis. We observed functional and pain improvement at 12 and 48 months (p < 0.0001), with statistically significant improvement on MRI scans at 12 months in cartilage loss, osteophytes, bone marrow lesions, effusion and synovitis (p < 0.01), and highly significant improvement in subchondral sclerosis (p < 0.0001). WJMSCs are safe and potentially effective in producing significant improvement in KOOS and MRI scores when administered intra-articularly in knee osteoarthritis cases under ultrasound guidance.