2025 ISAKOS Biennial Congress Paper
BMAC Intra-Articular and Subchondral Injections Versus Intra-Articular Injections for Knee OA Treatment: A Double-Blind Randomized Controlled Trial
Iacopo Romandini, MD, Doha QATAR
Luca Andriolo, MD, Bologna ITALY
Alessandro Di Martino, MD, Bologna, BO ITALY
Angelo Boffa, MD, Bologna ITALY
Simone Silva, MD, Gassino Torinese, Torino ITALY
Davide Reale, MD, Bologna ITALY
Stefano Zaffagnini, MD, Prof., Bologna ITALY
Giuseppe Filardo, MD, PhD, MBA, Prof., Lugano SWITZERLAND
IRCCS Istituto Ortopedico Rizzoli, Bologna, ITALY
FDA Status Cleared
Summary
Combining intra-articular with subchondral BMAC injections for the treatment of knee OA did not offer additional benefits compared to intra-articular injections alone, as both treatments showed significant clinical improvements at 12 months.
Abstract
Purpose
To investigate with a double-blind randomized controlled trial (RCT) the benefits of subchondral injections of bone marrow aspirate concentrate (BMAC) combined with an intra-articular injection of BMAC for the treatment of knee osteoarthritis (OA).
Methods
A total of 86 patients with medial knee OA (KL-2-3) were randomized in two groups: 43 patients (treatment group) received an intra-articular injection of BMAC combined with two subchondral injections of BMAC at the medial tibial plateau and femoral condyle. The other patients (control group) received an intra-articular injection only. BMAC was obtained from the homolateral anterior iliac crest and characterized for cell content. Patients were evaluated at 2-6-12 months using WOMAC (primary outcome), IKDC subjective/objective, EQ-VAS, EQ-5D-5, and Tegner scores. MR and CT scans were performed before treatment and at 12 months.
Results
The BMAC analysis confirmed the presence of 39.2±33.9 and 54.4±46.6 CFU-Fs at day 10 and 20, respectively. At the 12-month follow-up, both groups showed an improvement of all clinical scores compared to the baseline evaluation, with the WOMAC total score improving from 28.0±16.0 and 25.1±16.2 to 18.9±15 and 11.9±13.9 for the treatment and control group, respectively (both p<0.0005). Similar trends were found for the other clinical scores. Significant differences were found between the two groups in terms of WOMAC total score (p=0.033) and the IKDCsubj score (p=0.016) in favor to the control group at 12 months. No differences were documented in terms of MR and CT findings between the two groups. Two patients failed, one for each group, requiring a new treatment.
Conclusions
This is the first RCT directly investigating the added benefit of the subchondral BMAC injection to the intra-articular treatment. While both treatments offered significant clinical improvements, these study results question the use of subchondral BMAC injections for the treatment of patients with knee OA.