Associations of Longitudinal Multiparametric MRI Findings and Clinical Outcomes in Intra-Articular Injections for Knee Osteoarthritis

Abstract

Background Osteoarthritis (OA) is a complex heterogeneous disease and degradation of the articular cartilage is the hallmark of the disease. The aim of this study was to investigate the association of pre-structural and structural features and cartilage volume/thickness with clinical outcome in knee OA patients who received intra-articular injection for one year. Methods A total of 24 patients with mild-to-moderate OA were included in this retrospective study. Patients received intra-articular injections and were assessed for one year after treatment onset using knee Magnetic resonance imaging (MRI) results. OA features were assessed semi-quantitatively using a Whole Organ Magnetic Resonance Imaging score (WORMS). Cartilage thickness and volumes of the medial femoral condyle (MFC) and medial tibial plateau (MTP) were quantified. T1ρ and T2 values for MFC cartilage were measured. Clinical outcome was measured using Korean Western Ontario and McMaster Universities (K-WOMAC) score and Knee Injury Osteoarthritis Outcomes (KOOS) score. Spearman’s rank test was used to evaluate the associations between change of imaging findings and clinical parameters. Results MTP and MFC cartilage thickness and MTP cartilage volume at baseline showed significant associations with clinical outcome. Changes in WORMS cartilage score for the medial femorotibial joint (MFTJ) and total joint were significantly correlated with clinical outcome. Conclusion Thicker baseline MFTJ cartilage and less progressive MFTJ and total joint cartilage loss were associated with favorable clinical response over 12 months in knee OA patients undergoing intra-articular injection.