Osteoarthritis clinical features
Occurs in weight-bearing joints, distal finger joints commonly. Articular cartilage loses weight bearing ability, joint loses range of motion. Aching type of pain that gets better after rest, but worsens throughout day.
Osteoarthritis lab features
-Decrease in GAGs
-Low cell counts (<1000 WBC from synovial aspirate).
-Disorganized proteoglycan-HA chains.
Osteoarthritis radiographic features
-Narrowed joint space
-Sclerosis of subchondral bone
-Subchondral bone cysts
Rheumatoid arthritis clinical features
-Painful joint motion
Rheumatoid arthritis lab features
-Positive rheumatoid factor in serum
-Elevated erythrocyte sedimentation rate
-Positive for antinuclear antibody in 25 percent patients
-Inflammatory synovial fluid (2,000 to 50,000 WBC per mm^3, >25% are neutrophils)
Rheumatoid arthritis radiographic features
-Symmetric marginal erosions
-Soft tissue swelling
-Dislocation of joints