Osteoarthritis

Christopher Wise, MD
Medical College of Virginia at Virginia Commonwealth University, Richmond, VA

Definition/Key Clinical Features
Differential Diagnosis
Best Tests
Best Therapy

Definition/Key Clinical Features

• Degeneration of articular cartilage and reactive changes in surrounding bone and periarticular tissue
• Associated with aging, obesity, bone density, hormonal status, nutritional factors, joint dysplasia, trauma, occupational factors, hereditary factors
• Articular pain—hands, hips, knees, shoulders, cervical or lumbar spine
  • Worsens with activity, improves with rest
  • Usually chronic
  • Worsens gradually over time
• Osteophytes (bone spurs)
• Stiffness in morning (usually < 1 hour) and after sitting for extended periods
• Mild/moderate swelling
• Crepitus
• Bony enlargement
• Periarticular tenderness
• Possible synovial effusions (particularly in knee)
• Deformity, limited range of motion, loss of function, instability after many years of disease

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Differential Diagnosis

• Injury
• Inflammatory conditions
  • Rheumatoid arthritis
  • Ankylosing spondylitis
  • Reactive arthritis (Reiter syndrome)
  • Psoriatic arthritis
  • Polymyalgia rheumatica
• Malignancies
  • Metastatic breast cancer
  • Lung cancer
  • GI cancer
  • Myeloma
• Bone disease
  • Osteonecrosis (avascular necrosis)
  • Paget disease
  • Osteochondritis
  • Osteoporosis
• Metabolic arthritis
  • Gout
  • Calcium pyrophosphate deposition disease
  • Hemochromatosis
  • Ochronosis
  • Wilson disease
  • Acromegaly
• Tendinitis
  • Bursitis
  • Peripheral neuropathies
• Hereditary
  • Perthes disease
  • Chondrodysplasia

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Best Tests

• History and physical examination may be sufficient for diagnosis

Radiography: Characteristic Features

• Joint space narrowing, often asymmetrical
• Films of knees taken during weight bearing are helpful
• Subchondral bone sclerosis
• Subchondral cysts
• Osteophytes
• Subluxation or fusion of severely affected joints
• Central erosion in fingers
  

Lab Studies

• Useful only to rule out other diagnoses
• ESR, rheumatoid factor, uric acid usually normal
• Synovial fluid noninflammatory—no crystals and few leukocytes

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Best Therapy

Nonpharmacologic

• Exercise (focus on muscle strengthening, especially in knees)
• Weight loss
• Ensure adequate dietary calcium and vitamins C and D
• Patellar taping, wedged insoles, bracing, canes, or crutches

Pharmacologic Therapy for Osteoarthritis

• Acetaminophen: first choice for most patients; doses should be limited in patients with exposure to potentially hepatotoxic substances, especially alcohol
  • Dose: 3,000–4,000 mg/day
• NSAIDs: alternative; usually provide 50%–75% relief; risk of gastric ulcers and bleeding, hypertension, renal impairment, consider combining with gastroprotective agents (misoprostil, H2 blockers, proton pump inhibitors) in patients at risk for GI complications (age > 60 yr, prior ulcer disease, concomitant anticoagulant or corticosteroid use)
  • Ibuprofen
    • Dose: 600 mg q.i.d.
  • Naproxen
    • Dose: 500 mg b.i.d.
  • Nabumetone
    • Dose: 750–1500 mg q.d.
  • Diclofenac
    • Dose: 75 mg b.i.d.
  • Meloxicam
    • Dose: 7.5–15 mg q.d.
• Selective cyclooxygenase-2 (COX-2) inhibitors: efficacy equal to generic NSAIDs; can reduce GI complications
  • Celecoxib
    • Dose: 100–200 mg b.i.d.
• Acetaminophen/codeine: moderately effective; generally avoided but useful in selected patients; use with caution in elderly patients
  • Dose: one to two tabs/day
• Topical capsaicin: transient effect; may be useful in some patients, especially for hands and knees
  • Dose: 0.025% cream three to four times daily
• Tramadol: may be as effective as acetaminophen + codeine
  • Dose: 50 mg, four to six tabs/day
• Triamcinolone acetonide: for knee OA and effusion
  • Dose: 10–40 mg intra-articular injections every 3 mo
• Sodium hyaluronate: relieves pain for several months; comparable to NSAIDs; lasts longer than intra-articular steroids
  • Dose: 3–5 weekly intra-articular injections
    

Surgery

• Arthroscopic debridement of the knee
• Realignment of a degenerative knee
• Joint fusion (finger joints)
• Total joint replacement

September 2010