Osteoarthritis

Question 1

what is the typical presentation of osteoarthritis?

Answer 1

Pain worse at end of day, crepitus, stiffness , asymmetrical mainly on weight bearing (hip, knees, DIP, PIP CMC wrist) - NO inflam symptoms + seronegative

Question 2

Define osteoarthritis?

Answer 2

Age-related degenerative joint disease when cartilage destruction exceeds repair, causing pain and disability

Commonest joint condition

Question 3

what are the biggest risk factors for osteoarthritis?

Answer 3

AGE

Obesity(increase loading exacerbating trauma)

Occupation (heavy labour/lifting)

varus/valgus knee

Question 4

what are the commonly affected joints in osteoarthritis?

Answer 4

DIP, thumb carpo-metacarpal, knees

Question 5

outline the pathogenesis of osteoarthritis?

Answer 5

Chondrocytes are responsible for maintaining a balance between destruction and production of articular cartilage. In osteoarthritis, there is IRREVERSIBLE LOSS OF ARTICULAR CARTILAGE

Altered chondrocyte activity means there is increased destruction leading to loss of joint volume eventually

Chondrocytes weaken and undergo apoptosis-> Stimulates immune response leading to patchy chronic synovial inflammation

Fibrotic thickening of joint capsules

Eventually the bone becomes exposed, allowing it to rub with the neighbouring bone

Osteophytes also form – known as Heberden and Bouchard nodes

Question 6

what are the causes of primary osteoarthritis?

Answer 6

UNKNOWN AETIOLOGY

mutlifactorial aetiology

Question 7

what are the causes of secondary osteoarthritis?

Answer 7

disease that cause altered joint architecture and stability

• Developmental abnormalities (e.g. hip dysplasia)
• Trauma (e.g. previous fractures)
• Inflammatory (e.g. rheumatoid arthritis, gout, septic arthritis)
• Metabolic (e.g. haemochromatosis, acromegaly)
• Obesity
• Occupational
• FHx

Question 8

summarise the epidemiology of osteoarthritis?

Answer 8

COMMON

25% of those > 60 yrs

More common in FEMALES (post-menopausal), CAUCASIANS and ASIANS

Question 9

what are the presenting symptoms of osteoarthritis?

Answer 9

Joint pain and discomfort – usually localised to knee or hip

• Use-related
• Pain on movement and crepitus
• Worse at end of day
• Pain @ rest or night is unusual (more pain when you put weight on it)

Stiffness or gelling after inactivity lasting < 1 hour

Difficulty with certain movements

Feelings of joint instability

Restriction walking, climbing stairs and doing manual tasks

Systemic features are usually absent

Question 10

what are the signs of osteoarthritis on physical examination?

Answer 10

Local joint tenderness

Bony swellings along joint margins

• Heberden’s Nodes - DISTAL interphalangeal joint
• Bouchard’s Nodes - PROXIMAL interphalangeal joint

Crepitus and pain during joint movement

Joint effusion (remember GP doing the tapping thing!)

Restriction of range of joint movement

Question 11

what are the 4 classic features that are shown on the joint x ray in osteoarthritis?

Answer 11

Loss of joint space (narrowing)

Osteophytes

Subchondral cysts – fluid-filled sac that forms in joint space

Subarticular sclerosis

And chondrocalcinosis

Question 12

what are the appropriate investigations for osteoarthritis?

Answer 12

mainly clinical

joint x ray of affected joint- 4 classic features

CRP/ESR should be normal ( raised if another pathology)

Question 13

what investigations should you consider for osteoarthritis?

Answer 13

MRI should be ordered in spinal OA with neurological deficits, to identify and evaluate the extent and severity of spinal stenosis or nerve root entrapment.

Question 14

compare reactive and rheumatoid arthritis and osteoarthritis?

Answer 14