Bone marrow signal abnormalities in arthritis and trauma

Abstract

Joint pain and dysfunction are common presenting symptoms of both younger and older patients, resulting in significant cost and burden to the healthcare system. In both the acute and chronic setting, the advanced imaging evaluation for assessing joint dysfunction most commonly utilizes magnetic resonance imaging that allows for detailed evaluation of all components of a joint, including the cartilage, bone, fibrocartilage, and ligamentous components. Signal alterations of the subchondral bone and marrow have been recently recognized as an important component in both trauma and arthritis and modern treatment strategies focus on addressing both the cartilage and bone in an attempt to optimize joint preservation and restore function. The presence of bone marrow signal abnormalities is often associated with patient symptoms, cartilage loss, and risk of disease progression. A thorough understanding of the unique anatomy and biomechanics of the chondro-osseous junction can help to explain the many marrow signal abnormalities and clinical implications that are commonly encountered by imagers. In this review article, we will describe the anatomy and basic physiology of the subchondral bone, and discuss multiple pathologic appearances of the bone with an emphasis on edema-like signal changes seen in the setting of osteoarthritis and trauma.