Kellgren’s syndrome /kel″grinz/ [Henry Kellgren, Swedish physician, b. 1827] , a form of osteoarthritis affecting the proximal and distal interphalangeal joints, the first metatarsophalangeal and carpometacarpal joints, the knees, and the spine. The absence of rheumatoid factor and rheumatoid nodules and the lack of systemic involvement differentiate this syndrome from rheumatoid arthritis. Also called erosive osteoarthritis.