Degenerative vs. Inflammatory Joint Conditions

Question 1

What is the difference in age of onset?

Answer 1

• RA at any point (peaks at 30-40)

- OA later in life

Question 2

What is the difference in speed of onset?

Answer 2

RA rapid (weeks to months)
OA slowly (over years)

Question 3

What are the differences in joint symptoms?

Answer 3

RA - painful, swollen, stiff

OA - ache, tender, little/no swelling

Question 4

What are the differences in the patterns of joints affected?

Answer 4

• RA symmetrical = small and large joints

- OA unsymmetrical = begins on 1 side and spreads to other, 1 set of joints limited to, large weight bearing joints

Question 5

How long does joint morning stiffness last for each?

Answer 5

RA = longer than 1 hour
OA = less than 1 hour, returns at end of day or after period of inactivity

Question 6

What is the difference in the presence of symptoms?

Answer 6

• RA frequent fatigue, general feeling of being ill

- OA no systemic symptom

Question 7

What nodes do you get in OA?

Answer 7

• Heberden’s nodes = bony outgrowths on DIPs

- Bouchard’s nodes = bony outgrowths of PIPs

Question 8

What are the risk factors of OA?

Answer 8

• age
• obesity (especially at knee)
• abnormal mechanical loading (dysplasia)
• inherited type II collagen defects in premature polyarticular OA
• inheritance in nodal and erosive OA
• occupation (farmers)
• other arthritic conditions

Question 9

What are the causes of primary OA?

Answer 9

• idiopathic
• generalised
• erosive

Question 10

What are the causes of secondary OA?

Answer 10

• prior inflammatory disease (RA)
• due to mechanical congruity (dysplasia)
• endocrine disorders (diabetes, acromegaly)
• metabolic disorders

Question 11

What are the physical signs in OA?

Answer 11

• crepitus
• osteophytes
• deformity
• instability
• restricted movement
• effusion
• muscle weakness/wasting

Question 12

How can anaemia of chronic disease present as a result of RA?

Answer 12

• hypochromic normocytic anaemia
• dysregulation of iron homeostasis
• impaired proliferation of erythoid progenitor cells
• shortened lifespan of RBC
• decreased iron availability for RBC production
• blunted EPO response

Question 13

What are the 4 signs on a radiograph for OA?

Answer 13

• cartilage loss (joint space narrowing)
• osteophytes
• subchondral sclerosis
• trabeculae fractures/subchondral cysts

Question 14

What is erosive OA?

Answer 14

• more inflammatory form of OA
• confused with RA
• erosions of cartilage in DIP and PIP

Question 15

What joints does RA commonly affect?

Answer 15

• PIPs, MCP, carpals

- can affect any synovial joint but mostly small