What is Erosive Osteoarthritis?
Erosive OA occurs when there are significant erosive changes and soft tissue swelling in association with OA, potentially mimicking inflammatory arthropathies. However, the disease distribution does not change; there is still a predilection for the DIP joints, and there is generally a lack of bone demineralization. In addition, the erosions involve the subchondral bone centrally along articular surfaces as opposed to the bony margins in RA. When productive bony changes are also present in the periphery, one may observe a characteristic “gull wing” appearance ( Figure 49-3 ). Erosive OA is much more common in women than in men.