ABSTRACT: Osteoarthritis (OA) was considered a disease of articular cartilage but now is thought to involve the entire joint. Research findings have helped improve the understanding of disease progression and the strategies used to alter the disease course. There is no laboratory or pathological definition of OA; the diagnosis must be made clinically. The approach to treatment should be tailored to specific patients. Topical agents often are used before oral medications. NSAIDs and cyclooxygenase-2 inhibitors remain the mainstay of therapy. Intra-articular corticosteroid injections have been shown to provide short-term relief, and several hyaluronans are available for use in knee OA. Surgery may be required; modern implants provide significant pain relief and have proved to be durable and functional. (J Musculoskel Med. 2008;25:346-352)
Of the estimated 46 million Americans who have doctor-diagnosed arthritis,1 at least 27 million are affected by clinically symptomatic osteoarthritis (OA).2 Although OA—the most common arthritis—is considered a disease of aging, it also frequently affects working adults, representing the largest cause of disability and lost work days.
OA traditionally was considered a disease of articular cartilage. Now it is thought to involve the entire joint. The diagnosis must be made clinically, because laboratory tests may not be helpful and radiographic findings do not necessarily correlate with symptoms. The goals of treatment are to palliate pain, maintain and improve function, and retard disease progression; the effort should be multidisciplinary and include patient education, physical therapy and occupational therapy, and nonpharmacological and pharmacological interventions.
In this article,we describe current approaches to the diagnosis and management of OA. We also take a look at potential future treatments.
OA represents the final common clinical pathway from a variety of disease processes. In the traditional view, it is considered primary if no triggering cause can be identified or secondary if a preceding source (eg, major trauma) has been noted. In either case, OA is thought to be largely mediated through aberrant biomechanical forces transmitted across the joints.
Risk factors for OA usually are separated into those associated with disease development (incident OA) or disease progression. The main factors associated with incident OA are aging, previous trauma, genetic predisposition, and obesity (Table 1). For disease progression, most studies have focused on the knees and hips; the chief factors include mechanical alignment, quadriceps strength, and intra-articular and bone marrow features.
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