osteoarthritis (week 5)

Question 1

characteristics of OA

Answer 1

focal loss of articular cartilage
subchondral osteosclerosis
osteophyte formation at joint margin
remoddeling of joint contour

Question 2

osteoarthritis risk factors

Answer 2

genetics
developmental abnormalities
repetitive loading
adverse biomechanics
obesity
trauma
hormonal

Question 3

what happens to chondrocytes in OA

Answer 3

chondrocytes divide to produce metabolically active cells (should be terminally differentiated).

Question 4

what happens to cartilage matrix in OA

Answer 4

initially increased chondrocytes leads to increased matrix components, but there is also an accelerated degradation of components (aggrecan and type 2 collagen).
aggrecan concentration falls making cartilage vulnerable to load bearing injury

Question 5

what is fissuring of cartilage

Answer 5

deep vertical clefts, leads to localised chondrocyte death, decreased cartilage thickness

Question 6

what is bone underneath cartilage called

Answer 6

subchondral bone

Question 7

what is subchondral sclerosis

Answer 7

thickening of subchondral bone

Question 8

what is the name for replacement of hyaline cartilage with bone

Answer 8

endochondral ossification

Question 9

how are osteophytes formed

Answer 9

fibrocartilage is produced at the joint margin and undergoes endochondral ossification to form osteophytes

Question 10

what are the fluid filled spaces inside a joint extending from a bone

Answer 10

subchondral cyst

Question 11

pain from OA

Answer 11

insidious onset (months or years)
variable nature
related to movement and weight bearing
relieved by rest
brief morning stiffness (<15m)
only a few painful joints

Question 12

clinical signs

Answer 12

restricted movement
coarse crepitus
bony swelling around joint
deformity
muscle weakness/wasting

Question 13

generalised nodal OA characteristics

Answer 13

OA in interphalangeal joints
Heberden’s (DIP) and Bouchard’s (PIP) nodes
strong genetic predisposition
increased risk of other OA

Question 14

investigations for OA?

Answer 14

x-ray

Question 15

management

Answer 15

education
weight loss
pharmacological - paracetamol, NSAIDs
intra-articular glucocorticoid injections
joint replacement

Question 16

factors for OA in order

Answer 16

age, genetics, sex (female), obesity, joint trauma, occupation, muscle weakness, diet, smoking, alcohol