Which condition is characterized by the structure of joint pannus?

Rheumatoid arthritis is characterized by the presence of a structure known as pannus, which is a dense, abnormal tissue that forms in the synovial membrane of joints. This pannus invades and erodes adjacent cartilage and bone, leading to joint destruction and deformities. The inflammatory process in rheumatoid arthritis involves not only the synovium but also the surrounding connective tissues, resulting in the formation of this aggressive granulation tissue known as pannus.

In rheumatoid arthritis, persistent inflammation driven by immune mechanisms results in the accumulation of immune cells such as T-lymphocytes, plasma cells, and macrophages, contributing to the development of the pannus. The presence of pannus is a hallmark feature that distinguishes rheumatoid arthritis from other conditions that affect the joints. It is crucial in the pathology of the disease and underlies the progressive joint damage experienced by individuals with this condition.

Understanding this feature is significant as it informs both the diagnosis and the treatment approaches for rheumatoid arthritis, which often focuses on controlling inflammation and preventing joint damage.