Approach to Joint Pain Flashcards
1
Q
Briefly outline the pathophysiology of OA?
A
It’s an inherited disorder of cartilage repair leading to loss of cartilage
2
Q
On aspiration of the knee, what WBC cutoff is indicative of septic arthritis?
A
>100,000 cells/ml
3
Q
Outline the ACR 1987 classification criteria for RA diagnosis
A
Patients must have 4 out of these 7
- Morning stiffness >1 hour
- Swelling in joints of the hand
- Swelling in 3 or more joints
- Symmetrical joint swelling
- Erosions or calcifications on Xray
- Positive rheumatoid factor
- Rheumatoid nodules
4
Q
In terms of bifringency, compare gout and pseudogout
A
Gout has negatively bifringent crystals
Pseudogout has positively bifringent crystals
5
Q
What is the crystal in pseudogout?
A
Calcium pyrophosphate
6
Q
What are the X-ray finding in OA?
A
Osteophytes
Loss of joint space
Subchondral sclerosis
Subchondral cysts