Radiology

Ring and long digit radiograph in a patient with psoriatic arthritis. There is loss of the tuft to the ring finger (arrow), so called acroosteolysis. The long finger shows soft tissue swelling (asterisk) with severe joint space loss and erosions at the proximal interphalangeal (PIP) joint. The bone density is increased involving the proximal and middle phalanx to the long finger (ivory phalanx) related to periostitis, a characteristic feature of psoriatic arthritis. (Courtesy of Dr. A. Donovan)

Right foot radiograph in a patient with psoriatic arthritis. There is pencil-in-cup deformity involving the proximal interphalangeal (PIP) joint to the third toe (arrow). (Courtesy of Dr. A. Donovan)

Left long finger radiograph in a patient with psoriatic arthritis and dactylitis. Note soft tissue swelling at the proximal interphalangeal (PIP) joint. Arrows show proliferative new bone formation. There is moderate joint space loss at the PIP joint. (Courtesy of Dr. A. Donovan)

Left hand radiograph in a patient with rheumatoid arthritis shows extensive erosions at the distal radius, ulna, and carpus. Erosive changes are also seen at metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints. (Courtesy of Dr. A. Donovan)

Right hand radiograph in a patient with advanced rheumatoid arthritis with erosions of the distal radius and ulnar styloid, as well as severe joint space loss with erosions throughout the carpus with soft tissue swelling. (Courtesy of Dr. A. Donovan)

Right hand radiograph in a patient with advanced rheumatoid arthritis. There are extensive marginal erosions and ulnar subluxations at the metacarpophalangeal (MCP) joints. Erosions are also present at PIP joints. (Courtesy of Dr. A. Donovan)

Right wrist radiograph in a patient with rheumatoid arthritis. The arrows show erosions at the ulnar styloid and distal radius. Asterisk shows additional erosions at the carpus. (Courtesy of Dr. A. Donovan)

Left hip joint radiograph shows severe superior joint space narrowing, subchondral cysts, subchondral sclerosis and marginal osteophytes. These are radiographic hallmarks of osteoarthritis. (Courtesy of Dr. A. Donovan)

Bilateral hands in a patient with lupus. Note finger flexion and extension deformities in the absence of erosions. (Courtesy of Dr. A. Donovan)

Right wrist radiograph shows chondrocalcinosis involving the triangular fibrocartilage complex (arrow). (Courtesy of Dr. A. Donovan)