The natural history of knee, hip, and hand osteoarthritis (OA) is variable. Pathologic changes of OA generally remain stable or worsen, although some patients with hip osteoarthritis may actually sustain reconstitution of joint space. Even with stable pathology, patients often experience symptomatic improvement. Risk factors for OA progression include elderly age, coexistent crystal disease, concurrent OA in multiple joints (generalized disease), neuropathy, and, for knees, obesity.