Background: Osteoarthritis of knee is a chronic and debilitating problem of the elderly to which a satisfactory cure is yet to be found. Mesenchymal stem cells have been used in preclinical studies and were found effective in treating osteoarthritis. In this study we aim to evaluate the role of mesenchymal stem cells in treatment of primary osteoarthritis of knee in humans and analyze the results in clinical terms. Methods: 60 patients of osteoarthritis knee were randomly grouped into two categories by simple randomization. 30 patients each were allocated to group A (cases) and group B (controls). Fifteen ml of bone marrow was aspirated from patient’s sternum, concentrated stem cells solution was prepared and 1 ml of stem cell concentrate was injected into the knee joint of patients categorized as cases. Placebo injection of normal saline was given to controls. Patients were followed up at 1, 3, 6, 12, 18 and 24 months. In every follow up, patients were evaluated clinically using modified WOMAC index and compared with pre-treatment scores. The study was carried out in double blind manner. Statistical tests used were Mann Whitney test to compare the scores of cases and controls and Wilcoxon test to compare the paired data pre and post treatment within the case and control groups. Results: In group A mean [standard deviation [SD]] pre procedure pain score was 12.53 [1.187] and final score was 7.20 [1.474]. Mean [SD] pre procedure stiffness score in group A was 5.33 [0.976]. Final score was 2.47 [0.915]. Mean [SD] difficulty pre procedure score in Group A was 43.67 [5.394]. Final score was 26.00 [2.699]. Total pre procedure score in group A was 61.53 [6.300] and final score was 35.67 [4.806]. The reduction in all scores were statistically significant (p<0.001) compared to pre treatment values and compared to controls. There was no significant change pre and post-treatment in mean pain, stiffness, and difficulty and total scores in group B. Conclusion: Mesenchymal stem cells are an effective treatment modality for osteoarthritis. The one-stage stem cell isolation and injection procedure is safe, quick and cost effective in managing osteoarthritis.

Keywords: Osteoarthritis; Stem Cells; WOMAC Index