Objectives: To evaluate the main symptoms of knee osteoarthritis (OA) and tissue structure changes after a single dose bone marrow-derived mononuclear cell (BM MNC) intra articular injection. Case series study. Patients with knee OA Kellgren Lawrence (K-L) grade II and III received 1 injection of BM MNC. The clinical results were analyzed with the Knee injury and Osteoarthritis Outcome Score (KOOS) and Knee Society Score (KSS) before, 3, 6, and 12 months after injection. Radiological evaluation was performed with a calibrated x-ray and the magnetic resonance (MR) imaging before and 6 to 7 months postinjection.
Results: A total of 34 knees were treated with BM MNC injections. Mean (±SD) age of patient group was 53.96 ± 14.15 years; there were 16 males, 16 females, KL grade II, 16; KL grade III, 18. The average injected count of BM MNCs was 45.56 ± 34.94 × 106 cells. At the endpoint of 12 months 65% of patients still had minimal perceptible clinical improvement of the KOOS total score. The mean improvement of KOOS total score was +15.3 and of the KSS knee score was +21.45 and the function subscale +27.08 ( P < 0.05) points. The Whole Organ Magnetic Resonance Imaging Score (WORMS) improved from 44.31 to 42.93 points ( P < 0.05). No adverse effects after the BM-MNC injection were observed.
Conclusions: The single dose BM MNC partially reduces clinical signs of the knee osteoarthritis stage II/III and in some cases, decreases degenerative changes in the joint building tissue over 12-month period.
Keywords: articular cartilage; bone marrow; cartilage regeneration; knee magnetic resonance imaging; knee osteoarthritis; mononuclear cells; osteoarthritis disease modification; stem cells; tissue.