How should I assess a patient presenting with joint pain?

Assessment of Joint Pain

Begin with plain radiographs (minimum two views: AP and lateral) as the mandatory first imaging step, while simultaneously obtaining a detailed history focused on six key clinical factors: chronology (acute vs. chronic), presence of inflammation, distribution pattern (monoarticular vs. polyarticular), extra-articular manifestations, patient demographics, and disease course. 1, 2, 3

Immediate Triage: Rule Out Emergencies First

• Exclude septic arthritis immediately in any patient presenting with acute joint pain, fever, inability to bear weight, or a single hot, swollen joint—this is an orthopedic emergency requiring urgent aspiration 2, 4
• Obtain blood cultures if fever is present or symptoms are acute in onset 2
• For hip involvement with fever or severe pain, perform ultrasound-guided aspiration urgently to prevent permanent joint damage 2
• Joint aspiration with synovial fluid analysis is indicated when infection is suspected and should be guided by imaging 4, 5

History: Six Critical Clinical Factors

1. Disease Chronology

• Acute onset (days to weeks): Consider viral infections, crystal-induced arthritis (gout/pseudogout), serum sickness, reactive arthritis, or septic arthritis 3
• Chronic presentation (>6 weeks): Consider rheumatoid arthritis, osteoarthritis, or other chronic inflammatory arthritides—note that chronic conditions may present acutely 3, 6

2. Inflammatory vs. Noninflammatory Features

• Inflammatory arthritis presents with: 7, 3, 6

  • Warm, swollen joints with palpable synovitis
  • Prolonged morning stiffness (>1 hour)
  • Pain that improves with activity
  • Constitutional symptoms (fever, weight loss, fatigue)
  • Positive review of systems (rashes, oral ulcers, organ involvement)

• Noninflammatory arthritis (typically osteoarthritis) presents with: 7

  • Morning stiffness <1 hour
  • Pain aggravated by activity, improved with rest
  • Bony hypertrophy and crepitus on examination
  • Negative review of systems

3. Distribution Pattern

• Monoarticular: Septic arthritis, crystal arthropathy, trauma, or localized osteoarthritis 2
• Oligoarticular (2-4 joints): Reactive arthritis, psoriatic arthritis, or early rheumatoid arthritis 3
• Polyarticular (≥5 joints): Rheumatoid arthritis, systemic lupus erythematosus, viral arthritis, or generalized osteoarthritis 7, 6
• Symmetry: Symmetric involvement suggests rheumatoid arthritis; asymmetric suggests psoriatic or reactive arthritis 3

4. Extra-Articular Manifestations

• Document presence of skin rashes, oral ulcers, eye symptoms (uveitis, conjunctivitis), gastrointestinal symptoms, genitourinary symptoms, or pulmonary involvement 7, 3
• These findings help distinguish specific rheumatologic diagnoses 3

5. Patient Demographics

• Age, sex, occupation, family history of rheumatologic disease, and recent exposures (infections, travel, sexual contacts) 3, 8

6. Disease Course

• Progressive, relapsing-remitting, or self-limited pattern 3

Physical Examination: Systematic Joint Assessment

• Palpate for synovitis: Distinguish inflammatory synovial thickening from bony hypertrophy and crepitus of osteoarthritis 3, 6
• Assess for warmth, erythema, and effusion: Redness, warmth, or swelling suggests synovitis and inflammation 6
• Perform appropriately directed neurologic and musculoskeletal evaluation 1
• Document pattern of joint involvement: which joints, symmetry, and number affected 1, 3
• Examine for extra-articular findings (skin, eyes, mucous membranes) 3

Mandatory Initial Laboratory Workup

Obtain the following tests in all patients with undifferentiated joint pain: 4

Core Inflammatory Panel

• ESR and CRP: Complementary markers that differentiate inflammatory from non-inflammatory conditions and track disease activity 4
• Complete blood count with differential: Evaluate for infection, anemia of chronic disease, leukocytosis 4

Autoimmune Panel (if inflammatory features present)

• Rheumatoid factor (RF) and anti-CCP antibodies: Strongly predictive of rheumatoid arthritis diagnosis and prognosis 4
• ANA: If connective tissue disease suspected 4
• HLA-B27: If symptoms suggest reactive arthritis or axial involvement (back/spine pain) 4

Additional Testing Based on Severity

• Mild pain/inflammation: Consider autoimmune panel if symptoms persist 4
• Moderate to severe pain: Perform all initial tests plus viral hepatitis B and C, and tuberculosis screening before initiating DMARD therapy 4

Baseline Testing Before Medication Initiation

• CBC, liver function tests (ALT, AST), renal function (BUN, creatinine, urinalysis) for methotrexate, sulfasalazine, and NSAIDs 4
• Lipid profiles for tocilizumab and tofacitinib 4

Imaging Algorithm

Step 1: Plain Radiographs (Always First)

• Obtain plain radiographs before any other diagnostic or therapeutic intervention 1, 2, 5
• Minimum two views: anteroposterior (AP) and lateral 2
• For knee pain: AP, lateral at 25-30° flexion, and tangential patellar view 2
• Apply Ottawa Knee Rules to determine necessity 2
• Common pitfall: Approximately 20% of patients inappropriately receive advanced imaging without baseline radiographs—do not skip this step 2

Step 2: Advanced Imaging (When Indicated)

• MRI without contrast: Indicated when radiographs are normal or equivocal but clinical suspicion for inflammatory arthritis, infection, or soft tissue pathology remains 1, 5

  • Superior for detecting septic arthritis, osteomyelitis, synovitis, and early erosive changes 5
  • Use fluid-sensitive sequences (T2-weighted fat-saturated or STIR) to identify bone marrow edema and inflammatory changes 1
  • Gadolinium contrast may improve detection of subtle inflammatory lesions but does not significantly increase diagnostic accuracy for sacroiliitis 1

• CT without contrast: May be helpful for evaluating subtle erosions, complex anatomy (SI joints), or when MRI is contraindicated 1

  • Better than radiography for detecting early erosive changes but lacks sensitivity for direct inflammatory changes 1

• Ultrasound: Can detect synovial pathology, effusions, cortical erosions, and increased synovial blood flow (power Doppler) 1

  • Useful for guiding joint aspiration or injection 5
  • Not appropriate as a comprehensive screening examination 1

Step 3: Consider Referred Pain Sources

• Hip radiographs: If knee pain with unremarkable knee radiographs and clinical concern for hip pathology 1
• Lumbar spine radiographs: If knee pain with unremarkable knee radiographs and clinical concern for radicular symptoms 1

Psychosocial Evaluation (For Chronic Pain)

Document the following for patients with chronic joint pain: 1

• Presence of anxiety, depression, or anger
• Impact on activities of daily living
• Effect on mood, sleep, and interpersonal relationships
• Family, vocational, or legal issues
• Substance use or misuse history
• Patient expectations and coping mechanisms

Referral Criteria to Rheumatology

• Refer within 6 weeks of symptom onset if arthritis involves more than one joint with swelling not caused by trauma or bony enlargement 2
• Refer sooner if symptoms persist despite initial management or systemic symptoms are present 2
• Consult expert rheumatologist if differential diagnosis is unclear 1
• Earlier treatment initiation improves outcomes in inflammatory arthritis 2

Initial Management While Awaiting Workup

Conservative Measures (for traumatic effusion with normal radiographs)

• Appropriate if patient can bear weight fully and perform straight leg raise without difficulty 2
• Protection, rest, ice, compression, elevation (PRICE) 9

Pharmacologic Management

• NSAIDs (e.g., naproxen 500 mg twice daily): After evaluating gastrointestinal, renal, and cardiovascular status 2

  • Monitor CBC, LFTs, and renal function every 6-12 months 4

• Acetaminophen: Appropriate for mild pain without significant inflammation 2

• Do NOT initiate DMARDs (like methotrexate) until rheumatology consultation—these require specific monitoring protocols and specialist initiation 2

Common Pitfalls to Avoid

• Never skip plain radiographs before advanced imaging—this is the most common error 2
• Do not inject a joint without excluding infection first—this is an absolute contraindication 5
• Do not delay aspiration if septic arthritis is suspected—clinical red flags include fever, marked pain increase, local swelling, warmth, or systemic malaise 5
• Do not rely solely on classic rheumatologic laboratory tests—many are nonspecific; CBC, urinalysis, and metabolic panel may provide more useful diagnostic clues 3
• Do not assume bilateral structural abnormalities on imaging explain unilateral symptoms—correlation between imaging findings and pain is limited, especially in patients >70 years 1