Osteoarthritis gradually degrades subchondral bone, articular cartilage apart from causing problem like synovitis. Mesenchymal stromal cells are the clinically explored option to manage the severe condition of osteoarthritis but only short-term evidence are present, and therefore this study is conducted to explore long-term outcomes of the Mesenchymal stromal cells therapy. 

Mesenchymal stromal cells (MSCs) are one of the favorable choices to manage knee osteoarthritis (OA). Various short-term clinical trials evident the usefulness and safety of MSCs. However, very less evidence is present to govern the MSCs effects on osteoarthritis management. The long term clinical impact of MSCs was evaluated by considering patients from the previous randomized clinical trial (CMM-ART, NCT02123368).

Phase I/II randomized multicenter clinical trial with active control was introduced from 2012 to 2014. Thirty patients were randomized to:

•  Hyaluronic acid (intraarticularly) alone, or to two treatment groups
•  Hyaluronic acid together with 10 × 10⁶ or 100 × 10⁶ cultured autologous bone marrow-derived MSCs (BM-MSCs),
• Control group.  

Follow-up was done for one year. The clinical evolution and adverse effects were assessed using VAS and WOMAC after a follow-up of four years. 

After the administration of BM-MSCs or during the follow-up, no adverse effects were noted. Patients who received BM-MSCs get improved as per VAS and the median value of Low-dose, High-dose and control groups were changed from 7, 6 and 5 to 2, 3 and 7, respectively at the follow-up end. The patients received BM-MSCs also improved as per WOMAC, whereas the median noticed for Low-dose, High-dose and control groups were − 18, − 10 and 4, respectively (Low-dose vs. Control group p = 0.043). The BM-MSCs receiving groups showed no clinical difference.

The in- vitro expanded autologous BM-MSCs single intraarticular injection is a feasible and safe approach that exhibits long-term functional and clinical outcomes in knee OA management.