Osteoarthritis (OA) is a complex, heterogeneous condition that is a major public health problem, the most
common cause of disability in the aging population and is associated with a large economic burden. The
pathophysiology of OA affects the whole joint, with breakdown of cartilage, associated changes in the
subchondral bone and adjacent soft tissue that leads to debilitating symptoms such as pain. With the aging of
the population and the epidemic of obesity, the public health impact of OA, especially knee OA, has and will
continue to increase dramatically, but unfortunately, there are no FDA-approved disease-modifying OA drugs
(DMOADs), i.e., drugs designed to impede or prevent the OA-related structural changes to cartilage and bone.
This has been due to a lack of understanding of the relationship between features of OA and disease
progression. MRI, however, has improved our understanding of the relationship between histopathologic
changes and the structural changes to cartilage, subchondral bone and the surrounding soft tissues of the joint
in OA. As such MRI represents an improvement over plain knee radiographs, which are both insensitive and
nonspecific to critical changes in joint structure in the development and progression of OA.
The objective of this work is to understand the impact of the trajectory of BMLs and ES on downstream clinical
outcomes, including cartilage loss and disability, over the short-term (i.e., two years later) and long-term (i.e.,
six years later). Analysis of the trajectory of BMLs and ES will take into account the quantitative volume at
baseline and the quantitative change in volume over time.
The specific aims of this study are: To evaluate the impact of the trajectory of MRI-detected bone marrow
lesions (BMLs) and effusion synovitis (ES) on subsequent cartilage loss; and to evaluate the impact of the
trajectory of MRI-detected BMLs and ES on knee-specific disability.