Clinical features of osteoarthritis in the elderly.

Osteoarthritis (OA), the commonest form of arthritis, is an important cause of chronic morbidity. Assessment of patients with OA can be improved by the recognition of several patterns with which this disorder can present. When these patterns are delineated by a careful history, physical examination, appropriate radiographs and laboratory tests, it often leads to a more precise diagnosis and ultimately better management of these patients. The standard classification of primary and secondary OA, while useful, should be expanded to include clinically relevant patterns of disease.