Share your insights

Help us by sharing what content you've recieved in your exams


Chronic joint pain/stiffness

Differential Diagnosis Schema 🧠

Inflammatory Arthritis

  • Rheumatoid arthritis: Symmetrical joint involvement, morning stiffness lasting more than 30 minutes, small joint involvement (e.g., hands, feet)
  • Psoriatic arthritis: Asymmetrical joint involvement, dactylitis (sausage digits), associated with psoriasis (skin/nail changes)
  • Ankylosing spondylitis: Low back pain, morning stiffness that improves with exercise, young adult male predominance
  • Reactive arthritis: History of infection (e.g., gastrointestinal, genitourinary), asymmetric oligoarthritis, associated with uveitis/conjunctivitis

Degenerative Joint Diseases

  • Osteoarthritis: Common in older adults, affects weight-bearing joints (e.g., knees, hips), worse with activity, minimal morning stiffness
  • Cervical spondylosis: Neck pain, possible radiculopathy, may include neurological symptoms like tingling or weakness
  • Lumbar spondylosis: Lower back pain, potential radicular pain, worse with activity

Crystal Arthropathies

  • Gout: Acute onset, usually affects the first metatarsophalangeal joint (big toe), hyperuricemia
  • Pseudogout: Calcium pyrophosphate deposition, commonly affects the knee, chondrocalcinosis visible on X-ray

Infectious Arthritis

  • Septic arthritis: Single joint involvement, fever, history of joint trauma or surgery, elevated inflammatory markers
  • Lyme disease: Migratory arthritis, associated with erythema migrans (rash), history of tick bite

Systemic Diseases

  • Systemic lupus erythematosus (SLE): Polyarthritis, associated with malar rash, photosensitivity, multisystem involvement
  • SjΓΆgren’s syndrome: Arthralgia with dry eyes and mouth, parotid gland enlargement, commonly affects middle-aged women
  • Sarcoidosis: Polyarthritis, often involves ankles, associated with erythema nodosum and bilateral hilar lymphadenopathy

Key Points in History πŸ₯Ό

Pain Characteristics

  • Onset: Sudden onset suggests gout, septic arthritis, or trauma; gradual onset is more consistent with osteoarthritis or inflammatory arthritis
  • Duration: Acute pain (6 weeks) can differentiate between transient causes and chronic conditions
  • Pattern: Inflammatory arthritis tends to have morning stiffness that improves with activity, whereas osteoarthritis worsens with use
  • Severity: Severe pain may indicate septic arthritis or gout
  • Location: Joint distribution can help narrow the differential (e.g., small joints for rheumatoid arthritis, large joints for osteoarthritis)

Associated Symptoms

  • Systemic symptoms: Fever and malaise suggest inflammatory or infectious causes
  • Skin changes: Rash (e.g., malar rash in SLE, psoriasis in psoriatic arthritis)
  • Eye symptoms: Uveitis or conjunctivitis may suggest reactive arthritis or ankylosing spondylitis
  • Gastrointestinal symptoms: Diarrhea or genitourinary symptoms may point to reactive arthritis
  • Fatigue: Common in systemic diseases like SLE or SjΓΆgren’s syndrome

Background

  • Past medical history: Previous joint problems may suggest degenerative or inflammatory conditions
  • Drug history: Use of steroids or immunosuppressants may predispose to septic arthritis; diuretics are associated with gout
  • Family history: Autoimmune diseases (e.g., rheumatoid arthritis, SLE) can be familial
  • Social history: Occupation and lifestyle may indicate repetitive strain or traumatic joint injury

Possible Investigations 🌑️

Blood Tests

  • Inflammatory markers (CRP, ESR): Elevated in inflammatory and infectious arthritis
  • Rheumatoid factor (RF) and Anti-CCP: Positive in rheumatoid arthritis
  • Uric acid: Elevated in gout
  • Antinuclear antibodies (ANA): Positive in SLE and other connective tissue diseases
  • HLA-B27: Associated with ankylosing spondylitis and reactive arthritis

Imaging

  • X-rays: Useful for detecting osteoarthritis (joint space narrowing, osteophytes) and rheumatoid arthritis (joint erosions, osteopenia)
  • Ultrasound: Can identify joint effusions, synovitis, and guide aspiration
  • MRI: Helpful in early rheumatoid arthritis and for detecting soft tissue and bone marrow involvement
  • Dual-energy CT (DECT): Can detect urate crystals in gout

Joint Aspiration and Analysis

  • Synovial fluid analysis: Helps differentiate between inflammatory (e.g., gout, rheumatoid arthritis) and non-inflammatory conditions (e.g., osteoarthritis)
  • Microscopy: Identifies crystals (urate in gout, calcium pyrophosphate in pseudogout)
  • Culture: Essential for diagnosing septic arthritis

No comments yet πŸ˜‰

Leave a Reply

General practice