Figure 1.

Safety and efficacy of intra-articular injection of AT-MSCs for knee osteoarthritis. (a) MRI images of tibial condyles and medial femoral of the knee before or three or six months after the intra-articular injection of AT-MSCs showed a change in cartilage defect within six months. (b) At different time points, MRI images of femoral and tibial condyles showed a significant increase in cartilage defect at six months’ follow-up after injection of normal saline. (c−h) Visual analog scale (VAS) changes in knee pain and knee injury, and osteoarthritis outcome score (KOOS) score changes in AT-MSC intra-articular injection group and control group during six months. Adopted from Lee et al. and reprinted with permission of John Wiley and Sons.²¹