EPG Arthritis Knowledge Centre
Diagnosis
American College of Rheumatology Classification Criteria of Osteoarthritis
Classification Criteria for Osteoarthritis of the Hand:
These recommendations are from the American College Of Rheumatology (ACR). Please refer to the full guideline document1 for more detailed information.
Hand pain, aching, or stiffness and 3 or 4 of the following features:
- Hard tissue enlargement of 2 or more of 10 selected joints
- Hard tissue enlargement of 2 or more DIP (distal interphalangeal) joints
- Fewer than 3 swollen MCP (metacarpophalangeal) joints
Deformity of at least 1 of 10 selected joints
* The 10 selected joints are the second and third distal interphalangeal (DIP), the second and third proximal interphalangeal, and the first carpometacarpal joints of both hands. This classification method yields a sensitivity of 94% and a specificity of 87%. MCP = metacarpophalangeal.
Altman R, Alarcón G, Appelrouth D, Bloch D, Borenstein D, Brandt K, et al. The American College of Rheumatology criteria for the classification and reporting of osteoarthritis of the hand. Arthritis Rheum 1990;33:1601---10.
[1991] Combined Clinical (History, Physical Examination, Laboratory) And Radiographic Classification Criteria for Osteoarthritis of the Hip, Traditional Format*
These recommendations are from the American College Of Rheumatology (ACR). Please refer to the full guideline document2 for more detailed information.
Hip pain and at least 2 of the following 3 features:
- ESR<20 mm/hour
- Radiographic femoral or acetabular osteophytes
- Radiographic joint space narrowing (syperior, axial, and/or medial)
*This classification method yields a sensitivity of 89% and a specificity of 91%. ESR = erythrocyte sedimentation rate (Westergren).
R. Altman, G. Alarcon, D. Appelrouth, D. Bloch, D. Borenstein, K. Brandt, et al. The American College of Rheumatology criteria for the classification and reporting of osteoarthritis of the hip. Arthritis Rheum 1991;34:505--514.
[1986] Criteria for Classification of Idiopathic Osteoarthritis (OA) of the Knee*.
These recommendations are from the American College Of Rheumatology (ACR). Please refer to the original guideline document for more detailed information.
| Clinical and laboratory | Clinical and radiographic | Clinical† |
| Knee pain | Knee pain | Knee pain |
| + at least 5 of 9: | + at least 1 of 3: | + at least 3 of 6: |
|
- Age > 50 years |
- Age > 50 years |
- Age > 50 years |
|
- Stiffness < 30 minutes |
- Stiffness < 30 minutes |
- Stiffness < 30 minutes |
|
- Crepitus |
- Crepitus |
- Crepitus |
|
- Bony Tenderness |
+ Osteophytes |
- Bony Tenderness |
|
- Bony enlargement |
- Bony enlargement |
|
|
- No palpable warmth |
- No palpable warmth |
|
|
- ESR <40 mm/hour |
||
|
- RF <1:40 |
||
|
- SF OA |
||
| 92% sensitive | 91% sensitive | 95% sensitive |
| 75% specific | 86% specific | 69% specific |
* ESR = erythrocyte sedimentation rate (Westergren); RF = rheumatoid factor; SF OA = synovial fluid signs of OA (clear, viscous, or white blood cell count <2,000/mm3).
† Alternative for the clinical category would be 4 of 6, which is 84% sensitive and 89% specific.
R. Altman, E. Asch, D. Bloch, G. Bole, D. Borenstein, K. Brandt, et al. The American College of Rheumatology criteria for the classification and reporting of osteoarthritis of the knee. Arthritis Rheum 1986;29:1039--1049.
American College of Rheumatolgy Diagnosis Guideline for Rheumatoid Arthritis
These recommendations are from the American College Of Rheumatology (ACR). Please refer to the full guideline document3 for more detailed information.
Initial evaluation of RA
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The initial evaluation of the patient with RA should document symptoms of active disease (i.e., presence of joint pain, duration of morning stiffness, degree of fatigue), functional status, objective evidence of disease activity (i.e., synovitis, as assessed by gender and swollen joint counts, and the erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) level), mechanical joint problems (i.e., loss of motion, crepitus, instability, malalignment, and/or deformity), the presence of extra articular disease, and the presence of radiographic damage (Table 1). The presence of comorbid conditions should also be assessed. The patient’s and physician’s global assessments of disease activity and a quantitative assessment of pain using a visual analog scale or other validated measure of function or quality of life are useful parameters to follow during the course of the disease. This baseline information greatly facilitates assessment of disease progression and response to treatment.
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Baseline laboratory evaluations (Table 1) should include a complete blood cell count (with white blood cell differential and platelet counts), rheumatoid factor (RF) measurement, and measurement of ESR or CRP. Evaluation of renal and hepatic function is necessary, since many antirheumatic agents cause renal or hepatic toxicity and may be contraindicated if these organs are impaired. Since the hands and feet are so frequently involved in RA, radiographs of these joints as well as other affected joints establish a baseline for future assessment of structural damage. Arresting and preventing structural damage is a primary goal of therapy, and radiographic studies of major involved joints may be needed periodically.
| Table 1. Baseline evaluation of disease activity and damage in patients with rheumatoid arthritis |
Subjective
|
| * Performed only at baseline to establish the diagnosis. If initially negative, may be repeated 6–12 months after disease onset. † Performed at baseline, before starting medications, to assess organ dysfunction due to comorbid diseases. AST = aspartate aminotransferase; ALT = alanine aminotransferase. ‡ Performed at baseline, if necessary, to rule out other diseases. May be repeated during disease flares to rule out septic arthritis. § Helps to establish a baseline for monitoring disease progression and response to treatment. |
- Selection of the treatment regimen requires an assessment of prognosis. Poor prognosis is suggested by earlier age at disease onset, high titer of RF, elevated ESR, and swelling of >20 joints. Extra articular manifestations of RA, such as rheumatoid nodules, Sjögren’s syndrome, episcleritis and scleritis, interstitial lung disease, pericardial involvement, systemic vasculitis, and Felty’s syndrome, may also indicate a worse prognosis. Studies have shown that patients with active, polyarticular, RF-positive RA have a >70% probability of developing joint damage or erosions within 2 years of the onset of disease. Since studies have demonstrated that treatment with DMARDs (Disease Modifying Anti-Rheumatic Drugs) may alter the disease course in patients with recent-onset RA, particularly those with unfavorable prognostic factors, aggressive treatment should be initiated as soon as the diagnosis has been established.
References:
1. Altman R, Alarcon G, Appelrouth D, Bloch D, et al. The American College of Rheumatology Criteria for the Classification and Reporting of Osteoarthritis of the Hand. USA, Vol.33:No.11 (1990).
2. Altman R, Alarcon G, Appelrouth D, Bloch D, et al. The American College of Rheumatology Criteria for the Classification and Reporting of Osteoarthritis of the Hip. USA, Vol.34:No.5 (1991).
3. America College of Rheumatology Subcommitee. Guideline for the Management of Rheumatoid Arthritis (Special Report, 2002 Update). Vol.46:No.2:328-346 (2002).