How does arthritis in systemic lupus erythematosus differ from arthritis that deforms joints?

In the context of systemic lupus erythematosus (SLE), the associated arthritis is clinically distinguished by its nondeforming nature.12

While many inflammatory joint diseases, such as rheumatoid arthritis, involve progressive destruction of joint cartilage and bone that can lead to permanent deformity and ankylosis (fusion of the joint), the arthritis seen in SLE typically does not result in such structural damage. In rheumatoid arthritis, the inflammatory process often causes the loss of cartilage and the weakening of supporting structures like tendons and ligaments, which can lead to joint instability and partial dislocation.312

Conversely, the joint involvement in SLE is characterized primarily by inflammation that, while painful, does not progress to the severe, permanent architectural changes or joint destruction commonly associated with other chronic inflammatory arthropathies.12