While any diarthrodial joint can be involved in OA, the distal and proximal interphalangeal joints of the
hands are the most commonly affected, followed by the knees and the hips.
A diagnosis of OA is determined by joint symptoms, including pain and functional impairment or joint pathoanatomic changes, or both. A significant problem in addressing risk and progression of OA is the wide spectrum of clinical
features that depend in part on demographic factors and the joint affected. Although epidemiologically OA is often described by a single joint region, in reality patients often have OA in multiple joints