Internal Medicine II Practice Test

In rheumatoid arthritis the inflammatory process targets the synovium of small hand joints, and the destructive pannus that forms at the joint margin erodes adjacent bone. The radiographic hallmark in the hands is marginal erosions—erosions that occur at the margins of the joint, often at the metacarpophalangeal and interphalangeal joints. These erosions accompany juxta-articular osteopenia (loss of bone density near the joints) and progressive joint-space narrowing as the disease advances, eventually leading to characteristic hand deformities. So, the finding described as marginal erosions best fits RA in the hands because it reflects the targeted, margin-destroying bone damage driven by synovial inflammation. Other options point to sites or processes not typical for hand radiographs in RA (for example, cervical spine involvement like atlantoaxial subluxation, which isn’t a hand finding; vertebral changes or hip complications like AVN), so they don’t represent the classic hand radiographic feature of RA.