| Osteoarthritis (OA) is a chronic degenerative joint disease, characterized by the full thickness loss of cartilage, which is usually diagnosed by radiological assessment processes. The goal of this study was to develop diagnostic surrogates of OA utilizing magnetic resonance imaging and computed tomography. Our study focused on bone marrow lesions and morphometric bony changes in the OA knee, induced by anterior cruciate ligament transaction (ACLX) and medial meniscectomy (MMX) surgery in rabbit knee (stifle) joint. We measured edema-like bone marrow changes and the loss of a bony trabecular support structure in the femoral metaphysis of the ACLX injury model as early as the 6th week, however, neither of these changes were seen in the MMX injury model. Anatomically, the trabecular support structure is cancellous bone proximal to the growth plate in the femoral metaphysis. Its morphological "rafter-like" appearance mirrors that of an engineering support, providing support to the overlying femoral cortical bone. Adaptations to this trabecular bone may reduce the compliance of cortical bone that structurally supports the overlying cartilage, which may result in the progression from joint injury to early OA. Thus, we characterized these edema-like and bony lesions after ACL disruption in the knee for potential use as diagnostic surrogates of early OA. |
