Single intraarticular injection of in vitro expanded autologous bone-marrow mesenchymal stromal cells was found to be a safe and effective in providing long-term clinical and functional improvement in patients with knee osteoarthritis, as per a study published in the 'Journal of Translational Medicine'.

For knee OA treatment, MSCs prove to be capable enough. In the past, many short-term clinical trials have been conducted to study the safety and effectiveness of MSCs. However, there is lack of data evaluating long term outcomes of MSC in OA patients. The authors investigated the patients included in their previous randomized clinical trial to determine the long-term clinical effect.  The trial was carried out between 2012 and 2014. Thirty patients diagnosed with knee OA were randomly assigned to

• 2 treatment groups, hyaluronic acid together with 10 × 10⁶ or 100 × 10⁶ cultured autologous bone marrow-derived MSCs (BM-MSCs)
• control group
• intraarticularly administered hyaluronic acid alone

Patients were followed up for one year. VAS and WOMAC scorings were noted after a follow up of 4 years. No adverse events were observed after the BM-MSCs administration or during the follow-up. As per VAS, the BM-MSCs-administered patients showed reduction in pain. Clinical improvement was observed in the patients receiving BM-MSCs according to the WOMAC scores. Increase in the median value of 4 points (− 11; 10) was observed in the control group while low-dose and high-dose groups showed values of − 18 (− 28; − 9) and − 10 (− 21; − 3) points, respectively. BM-MSCs receiving groups showed no considerable clinical differences.