Degenerative versus Inflammatory Joint Conditions

Question 1

What is the most common form of arthritis?

Answer 1

Osteoarthritis

Question 2

What percentage of the population suffer from rheumatoid arthritis?

Answer 2

1%

Question 3

Compare the disease onset of rheumatoid and osteoarthritis

Answer 3

OA = slow, over years
RA = relatively rapid (weeks to months)

Question 4

Compare the joint symptoms of rheumatoid and osteoarthritis

Answer 4

OA = joints ache and tender
RA = joints are painful, swollen and stiff

Question 5

Which joints are often affected by rheumatoid arthritis?

Answer 5

Small and large joints on both sides of the body; hands, wrists or elbows, balls of the feet etc.

Question 6

Which joints are often affected by osteoarthritis?

Answer 6

Often unilateral and are in the DIPs, PIPs, thumbs or large weight-bearing joints such as hips, knees and spine

Question 7

Compare the duration of morning stiffness between rheumatoid and osteoarthritis

Answer 7

OA = lasts less than an hour (returns at the end of the day or after physical activity) 
RA = lasts longer than an hour

Question 8

In which ethnicities is osteoarthritis of the hip uncommon?

Answer 8

Africans and asians

Question 9

In which ethnicities is polyarticular osteoarthritis uncommon?

Answer 9

Africans and Malaysians

Question 10

What predisposes individuals to develop premature polyarticular osteoarthritis?

Answer 10

Inherited type II collagen defects

Question 11

What are the four signs of osteoarthritis on x-ray?

Answer 11

> Joint space narrowing (cartilage loss)
Osteophytes
Subchondral sclerosis (white line by exposed bone)
Trabeculae fractures/subchondral cysts

Question 12

Name two types of osteoarthritis.

Answer 12

Nodal generalised OA and erosive OA

Question 13

What is nodal generalised osteoarthritis?

Answer 13

Affects small joints of the hands primarily (Herberden’s/Bouchard’s nodes) and disease often starts around the time of menopause BUT HRT doesn’t help symptoms or progression

Question 14

What is erosive osteoarthritis?

Answer 14

An inflammatory form of OA that often affects the DIPs, characterised by erosions of cartilage in the hands and is often present in middle-aged/post-menopausal women and is often confused with rheumatoid arthritis

Question 15

How do you diagnose rheumatoid arthritis?

Answer 15

Rheumatoid factor (IgM antibody to the Fc portion of IgG)

Question 16

What is rheumatoid factor?

Answer 16

It’s a IgM antibody to the Fc portion of IgG antibodies. It is found in 60-80% of patients with rheumatoid arthritis

Question 17

What two antibodies can be tested for to diagnose rheumatoid arthritis?

Answer 17

Rheumatoid factor and anti-citrullinated peptide antibodies

Question 18

Why may rheumatoid arthritis lead to anaemia of chronic disease?

Answer 18

As the activation of monocytes and T-cells due to inflammation causes:
> Inhibition of EPO release
> Inhibits erythroid proliferation in red bone marrow
> Increases hepatic synthesis of hepicidin which prevents iron release –> fewer red blood cells produced
> Augments haemophagocytosis (also prevents iron release)