Extensive erosive changes and alignment abnormalities are observed along the articular surfaces of the 2nd through 5th PIP and DIP joints bilaterally, as well as at the 1st IP, MCP and carpometacarpal joints bilaterally. These erosive changes assume a gull wing appearance. The alignment abnormalities involving the 1st digits resemble a hitchhiker's thumb. There are no significant erosive changes involving the radiocarpal or intercapral joints, and the 2nd-5th MCP joints are also spared.