Porth's Essentials of Pathophysiology, 4e

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Musculoskeletal Function

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symptom of vasculitis. The visceral organs, such as the heart, lungs, and gastrointestinal tract, also may be affected. Dryness of the eyes, mouth, and other mucous mem- branes may occur, especially in advanced disease. Ocular manifestations include episcleritis, scleritis, and scle- romalacia, which is due to scleral nodules. Additional extra-articular manifestations of RA include pulmonary fibrosis and pericarditis. A small number of persons have splenomegaly and lymph node enlargement. Diagnosis. The diagnosis of RA is based on findings of the history, physical examination, and laboratory tests. In 2010, the American College of Rheumatology/ European League Against Rheumatism collaborated to develop new classification criteria for RA 39 (Chart 44-2). The new criteria are aimed at diagnosing RA earlier in persons who meet the 1987 classification criteria. Because changes in joint structure usually are not vis- ible early in the disease, diagnosis is often difficult. On physical examination, the affected joints show signs of inflammation, swelling, tenderness, and possibly warmth and reduced motion. The joints have a soft, spongy feel- ing because of the synovial thickening and inflamma- tion. Body movements may be guarded to prevent pain. The combined serologic presence of the RF and ACPA are findings that are sensitive and fairly specific for RA. 3,4,37 The presence of ACPA, which are often detected very early in RA, appear to be a good prog- nostic marker for the disease and discriminates between erosive and nonerosive forms of the disease. Disease severity and activity tend to correlate with RF levels; patients with high RF levels tend to have a significantly higher frequency of extra-articular involvement (e.g., rheumatoid nodules, vasculitis, neuropathy). Synovial fluid analysis can be helpful in the diagnostic process. The synovial fluid has a cloudy appearance, the white blood cell count is elevated as a result of inflamma- tion, and the complement components are decreased. Radiologic findings provide the most specific evidence of joint changes in RA, but are often normal during the early stages of the disorder. Treatment. The treatment goals for a person with RA are to reduce pain, minimize stiffness and swelling, maintain mobility, and become an informed health care consumer. The treatment plan includes education about the disease and its treatment, physical rest, therapeutic exercises, and medications. Because of the chronicity of the disease and the need for continuous, long-term adherence to the prescribed treatment modalities, it is important that the treatment be integrated with the per- son’s lifestyle. Both physical rest and therapeutic exercises are important aspects of care. 36 Physical rest reduces joint stress. Rest of specific joints is recommended to relieve pain. For example, sitting reduces the weight on an inflamed knee, and the use of lightweight splints reduces undue movement of the hand or wrist. Although rest is essential, therapeutic exercises also are important in maintaining joint motion and muscle strength. 37,38

CHART 44-2   Criteria for Classification of Rheumatoid Arthritis Patient Characteristics* Score (points) Distribution of affected joints (number and site) 2 to 10 large joints (shoulders, elbows, hips, knees, and ankles) 1 1 to 3 small joints (metacarpophalangeal joints, proximal interphalangeal joints, 2nd through 5th metatarsophalangeal joints, thumb interphalangeal joints, and wrists) 2 4 to 10 small joints 3 Greater than 10 joints (including at least 1 small joint) 5 Serology (RF or ACPA) Low positive (above the upper limit of normal, ULN) High positive (greater than three times the ULN) 2 3 Acute phase response (ESR or CRP) above the ULN 1 Symptom duration at least 6 weeks 1 In addition to those that meet these criteria, which are best suited to persons with newly presenting disease, the following patients are classified as having RA: ■■ Persons with erosive disease typical of RA with a history compatible with prior fulfillment of the criteria ■■ Persons with longstanding disease, including those with inactive disease (with or without treatment) who have previously fulfilled these criteria upon retrospectively available data *Classification of definite RA based upon the presence of synovitis in at least one joint, the absence of an alternative diagnosis that better explains the synovitis, and the achievement of a total score of at least 6 (of a possible 10) from the individual scores in four domains.The highest score achieved in a given domain is used for this calculation.These domains and their values are: ACPA, anti-cyclic citrullinated peptide antibodies; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; RF, rheumatoid factor. Adapted from: Aletaha D, NeogiT, Silman AJ, et al. Rheumatoid arthritis classification criteria: an American College of Rheumatology/European League Against Rheumatism collaborative initiative. Arth Rheum. 2010;62(9):2569.

Proper posture, positioning, body mechanics, and the use of supportive shoes can provide further com- fort. There often is a need for information about the