Osteoarthritis Flashcards
What is a huge hint that a patient has post-traumatic osteoarthritis?
Past trauma in joint
UNILATERAL
What does the cartilage in osteoarthritis look like?
cartilage with surface irregularities (clefts and cloning of chondrocytes)–> end stage has marked thinning and new osteophyte growth at edges
What is a characteristic physical examination finding in osteoarthritis?
fine grinding of the joint (crepitus)
What are the characteristics of normal synovial fluid?
Leukocyte count <25% PMNs
What are characteristics in the synovial fluid in osteoarthritic knee?
Leukocyte count 200-2000/mm^3 with 25% PMNs
What are the characteristic of synovial fluid in infection?
Leukocyte count >100,000/mm^3 with >85% PMNs
What joints are typically involved in primary osteoarthritis?
cervical spine (C3-C7), lumbar spine, hip joints, knee joints, DIPs, PIPs, thumb, 1st MPT joint of foot, 1st carpal-metacarpal joint (thumb) ONLY
What areas are involved in RA but not osteoarthritis?
wrist, elbows, shoulders, jaw
What are Heberden nodes?
osteophytes at DIPs (usually in women)
What are Bouchard’s nodes?
osteophytes at PIPs (less common in osteoarthritis)
What is the first joint affected in the hand in osteoarthritis?
carpometacarpal joint of the thumb
What are the symptoms of a patients with hip joint osteoarthritis?
deep groin pain the radiates into the medial thigh and pain with internal and external rotation
What is a differential diagnosis for hip joint pain due to osteoarthritis?
trochanteric bursitis
What causes cartilage breakdown in osteoarthritis?
mechanical forces are exerted on the cartilage over time (or due to injury) can cause cartilage to make molecules (Plasmin–> stimulates MMPs) that degrade cartilage
What is the major type of collagen in cartilage of joints?
type II collagen
What breaks down type II collagen?
collagenease 1
How are chondrocytes involved in the process of osteoarthritis?
receive signals from mechanical forces to produce NO and IL-1 to tell other chondrocytes to produce NO, IL-1, TNF-alpha, and PGE2
What does PGE2 cause?
pain and neutrophil chemotaxis
How rapidly does the process of chemokine release occur in osteoarthritis?
slow release (so degree of inflammation is not that high)
What do osteoarthritis joints feel like?
NOT warm (as you would see with infection or RA joint)
How does having an underlying trauma alter the process of osteoarthritis?
speeds up the process
How do you treat osteoarthritis?
Tylenol, NSAIDs, intra-articular steroids
What are secondary causes of osteoarthritis?
- previous trauma/overuse
- consider neuromuscular disease (diabetes or other neuropathies)
- Metabolic disorders (CPPD or pseudogout)
If you have arthritis in joints that are NOT typical for osteoarthritis, what should you do?
Check for secondary causes (diabetic neuropathy, trauma, hemochromatosis, hyperparathyroidism, hypothyroidism, neuropathic joint (syphilis, diabetes), hypomagnesemia, aging, etc.)