Osteoarthritis (OA) Flashcards
Osteoarthritis (OA)
Etiology and Pathophysiology
Slowly progressive noninflammatory disorder of the diarthrodial
joints
• Not normal part of aging process
• Cartilage destruction begins between ages 20 and 30 but
symptoms do not manifest until after age 50–60
• Caused by direct damage or instability
• Risk factors
Etiology and Pathophysiology continued…
New joint tissue forms in response to cartilage destruction.
Cartilage becomes dull, yellow, and granular; Soft and less
elastic; Less able to resist wear with heavy use
• Fissuring/erosion of articular surfaces
• Formation of osteophytes
• Secondary synovitis may result
• Contributes to early pain and stiffness
• Pain in later disease from contact between exposed bony joint
surfaces
Clinical Manifestations
Systemic manifestations are not present in OA
• Joint pain
• Predominant symptom ranging from mild discomfort to significant
disability
• Pain worsens with joint use
• Early stages: rest relieves pain
• Later stages: pain with rest and sleep is disturbed because of pain and increased
joint discomfort
• Pain may be referred to groin, buttock, or medial side of thigh or
knee
Clinical Manifestations
Joints
Sitting down becomes difficult, as does getting up from a chair
when hips are lower than knees
• Joint stiffness occurs after periods of rest or static position
• Early morning stiffness usually resolves within 30 minutes
• Overactivity → mild joint effusion, temporarily ↑ stiffness
• Crepitation
• Asymmetrical
Clinical Manifestations
Deformity
Specific to involved joint • Heberden’s nodes (DIP joint) and Bouchard’s nodes (PIP joint) • Red, swollen, and tender • No significant loss of function • Visible disfigurement • Knee: bowleg, altered gait • Hip: one leg shorter
Diagnostic Studies
- Bone scan, CT scan, MRI
- Early joint changes
- X-rays
- Detect joint space narrowing, bony sclerosis, osteophyte formation
- No specific lab abnormalities
- Synovial fluid analysis
