Physical Examination for Rheumatoid Arthritis
Clinical examination is the method of choice for detecting arthritis in suspected RA, focusing on systematic joint palpation for swelling, tenderness, and warmth, particularly in the small joints of the hands and feet. 1
Initial Clinical Assessment
The examination should prioritize identifying definite joint swelling (not just tenderness) that cannot be explained by another disease, as this is the cornerstone diagnostic criterion. 1 The likelihood of RA increases with the number of small joints involved. 2
Key Joint Examination Technique
Palpate for synovitis by assessing:
- Metacarpophalangeal (MCP) joints - squeeze test across all MCPs simultaneously to detect tenderness and swelling 3
- Proximal interphalangeal (PIP) joints - examine each joint individually for boggy swelling 3
- Wrist joints - assess for dorsal and volar swelling, particularly over the ulnar styloid 3
- Metatarsophalangeal (MTP) joints - squeeze test across the forefoot 3
- Knee joints - assess for effusion and synovial thickening 3
Pattern Recognition
Look for the characteristic symmetric polyarthritis pattern. 3 RA typically spares the distal interphalangeal joints, sacroiliac joints, and lumbar spine - involvement of these areas should prompt consideration of alternative diagnoses. 3
Essential Clinical Features to Document
Morning Stiffness Assessment
Specifically ask about stiffness lasting at least 1 hour before maximal improvement - this is a typical sign of RA and correlates with disease activity. 3 Ensure the patient understands the difference between pain and stiffness, as this is a subjective measure. 3
Joint-Specific Findings
- Hand involvement: Tender swelling on palpation of MCPs, PIPs, and wrists with severe motion impairment, even before radiologic bone damage appears 3
- Tendon and bursal involvement: Examine for tenosynovitis (particularly flexor tendons) and bursitis, which are frequent and often clinically dominant in early disease 3
Confirmatory Imaging During Examination
Ultrasonography can confirm arthritis detected on clinical examination and may reveal subclinical synovitis when clinical findings are equivocal. 1 Power Doppler ultrasound of the wrist and MCP joints can identify active synovitis and serves as a useful adjunct for early diagnosis when patients don't meet 2010 ACR/EULAR criteria. 1
Extra-Articular Manifestations to Examine
Assess for:
- Rheumatoid nodules - firm subcutaneous nodules, typically over extensor surfaces 3
- Constitutional signs - document fatigue, fever, weight loss, and malaise 3
- Pulmonary examination - auscultate for crackles suggesting interstitial lung disease, particularly in high-risk patients 1
Critical Pitfalls to Avoid
Do not delay rheumatology referral based on negative rheumatoid factor or normal acute phase reactants. 1, 4 Patients should be referred within 6 weeks of symptom onset if they have any joint swelling with pain or stiffness. 1
Do not rely solely on laboratory tests - more than 30-40% of RA patients have negative RF or anti-CCP antibodies, and 40% have normal ESR or CRP. 5 The clinical examination remains paramount.
Do not overlook monoarticular presentations - RA can present acutely in a single joint, though symmetric small joint polyarthritis is most common. 3