, Example of a high-risk erosive hand osteoarthritis pedigree identified in the Utah Population Database. Circles = females, squares = males, arrow = family founder, slashes = deceased. White circles/squares = affection status unknown. Black circles/squares = individuals affected with erosive hand osteoarthritis. B, C, D indicate individuals with hand radiographs. B-D, Hand radiographs of individuals (B-D) in the high-risk EOA pedigree (A). Asterisks indicate central subchondral erosions and arrowheads indicate a ‘gull-wing’ appearance of the joint.