Higher Knee Loading Correlates To Greater Cartilage Degeneration 2 Years After Anterior Cruciate Ligament Reconstruction

Purpose: Recent MRI studies suggest that increased knee joint loading in the first 6 months after ACL reconstruction (ACLR) is associated with compositional deterioration, as evidenced by elevated MRI T2, of medial compartment cartilage. However, the degree to which these early associations remain predictive of longer-term trends in knee cartilage health are unclear. Vertical ground reaction force (vGRF) analyses suggest that symptomatic ACLR subjects tend to underload the ACLR limb compared to the contralateral uninjured limb within the first year after reconstruction but then tend to overload the ACLR limb at 2 or more years after surgery. The goal of this work is to assess if ambulatory knee loading is associated with medial compartment knee cartilage degeneration at 2 years post-ACLR. We hypothesize that greater interlimb differences in vGRF as well as knee flexion (KFM) and adduction (KAM) moments will associate with greater interlimb differences in medial cartilage MRI T2 values where higher loading of the ACLR knee will be reflected by higher cartilage T2 values in that knee.