Current trends of stem cell-based approaches for knee osteoarthritis

Introduction Osteoarthritis (OA) is the most prevalent joint disorder resulting in cartilage destruction, subchondral sclerosis, osteophyte formation, and synovitis. Knee osteoarthritis presents a great clinical challenge to clinicians due to the limited inherent repair capacity of avascular, aneural articular cartilage. Articular cartilage defects are increasingly common among the elderly causing severe pain, joint stiffness, reduced motion, disability, and deformity among affected patients. Although cartilage defects are typical features of OA, current treatments can barely restore the full function of native cartilage. Recent studies have provided new perspectives for cartilage engineering using multipotent mesenchymal stem cells (MSCs). Growing knowledge on the biology of MSCs has provided new insights into their clinical applications, particularly for OA. MSCs isolated from a variety of adult tissues including the bone marrow, have the capacity to differentiate into different cell types such as bone and cartilage and have therefore attracted scientific interest as possible therapeutic tools and hold promise for cartilage regeneration. At present, regenerative medicine offers the exciting potential for treating osteoarthritis. In this review, we highlight recent researches that address critical challenges of stem cell based therapies for OA. Furthermore, we provide innovative studies that have been carried out in the potential treatments for knee osteoarthritis, including stem cells and tissue engineering. Conclusion The utility of stem cells for the treatment of osteoarthritis is increasing in clinical researches. Modes of delivery of stem cells to the articular cartilage differ from direct injection to implantation with composite scaffolds. Currently, there is limited evidence of direct clinical benefit and randomized, prospective studies for these innovations should be conducted to validate the safety and efficacy of cartilage regeneration.