26: Osteoarthritis

Essentials of Diagnosis

General Principles in Older Adults

Osteoarthritis (OA) is the most common disease of the joints and is one of the leading causes of disability among older adults in the United States. Older age is the greatest risk factor for OA; the prevalence of symptomatic knee OA was 12.1% among adults age ≥60 years. OA is a complex disorder with multiple risk factors that range from genetic, demographic, metabolic, and biomechanical factors to congenital or developmental deformities of the joint. The diagnosis is based on history (ie, symptoms of joint pain, often with transient morning stiffness), physical examination (ie, crepitus, bony tenderness and bony enlargement) and characteristic radiographic features (ie, joint space narrowing with osteophytes). The multidisciplinary team approach used in geriatric medicine clearly applies to managing the OA patient. Nonpharmacologic measures are critically important in the management of OA in older adults and include aerobic, aquatic, and/or resistance exercises, as well as weight loss for overweight patients. Patient education and psychosocial support are as important as medical therapy, particularly in older adults. Pain relief is the primary indication for the use of pharmacologic agents in patients with OA who do not respond to nonpharmacologic interventions. Because of its efficacy–toxicity profile, acetaminophen is often the initial therapy, and nonsteroidal antiinflammatory drugs (NSAIDs) may be prescribed for those who have inadequate response to acetaminophen. Oral NSAIDs should be used with great caution in older adults given the increased risk of side effects, with topical NSAIDs offering a better efficacy–toxicity profile. Other pharmacologic modalities, including tramadol, intraarticular corticosteroid injections, intraarticular hyaluronate injections, duloxetine, and opioids, are conditionally recommended in patients who have had an inadequate response to initial therapy. Surgical interventions are generally reserved for those who have failed medical therapy, and thus have persistent pain and marked limitations in activities of daily living. The natural course and prognosis of OA largely depends on the joints involved, the underlying risk factors, the presence of symptoms, and the severity of the condition. Recent studies show an increased mortality among persons with OA compared with the general population. Therefore, management of older patients with OA should also focus on effective treatment of cardiovascular risk factors and comorbidities, as well as on increasing physical activity.

Prevention

The best treatment for OA is prevention. However, OA is often diagnosed in its later stages, and there are no proven therapies that can prevent the progression of joint damage caused by OA. Advances in imaging modalities, especially MRI, and innovations in molecular biology have greatly advanced our knowledge of OA, and efforts are ongoing to identify preclinical biochemical and imaging biomarkers that will provide opportunities to diagnose and treat OA earlier so as to prevent further ...