Multi-vendor multi-site quantitative MRI analysis of cartilage degeneration 10 Years after anterior cruciate ligament reconstruction: MOON-MRI protocol and preliminary results

Objective: To describe the protocol of a multi-vendor, multi-site quantitative MRI study for knee post-traumatic osteoarthritis (PTOA), and to present preliminary results of cartilage degeneration using MR T-1 rho and T-2 imaging 10 years after anterior cruciate ligament reconstruction (ACLR). Design: This study involves three sites and two MR platforms. The patients are from a nested cohort (termed as Onsite cohort) within the Multicenter Orthopaedic Outcomes Network (MOON) cohort 10 years after ACLR. Phantoms and controls were scanned for evaluating reproducibility. Cartilage was automatically segmented, and T-1 rho and T-2 were compared between operated, contralateral, and control knees. Results: Sixty-eight ACL-reconstructed patients and 20 healthy controls were included. In phantoms, the intra-site coefficients of variation (CVs) of repeated scans ranged 1.8-2.1% for T-1 rho and 1.3-1.7% for T-2. The inter-site CVs ranged 1.6-2.1% for T-1 rho and 1.1-1.4% for T-2. In human subjects, the intra-site scan/rescan CVs ranged 2.2-3.5% for T-1 rho and 2.6-4.9% for T-2 for the six major compartments. In patients, operated knees showed significantly higher T-1 rho and T-2 values mainly in medial femoral condyle, medial tibia and trochlear cartilage compared with contralateral knees, and showed significantly higer T-1 rho and T-2 values in all six compartments compared to healthy control knees. The patient contralateral knees showed higher T-1 rho and T-2 values mainly in the lateral femoral condyle, lateral tibia, trochlear, and patellar cartilage compared to healthy control knees. Conclusion: A platform and workflow with rigorous quality control has been established for a multi-vendor multi-site quantitative MRI study in evaluating PTOA 10 years after ACLR. Our preliminary report suggests significant cartilage matrix changes in both operated and contralateral knees compared with healthy control knees. (c) 2022 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.