Pathology - Bone Disease

Question 1

what is the diagnostic threshold for osteopenia?

Answer 1

1-2.5 SD below the mean peak bone mass

Question 2

what is the diagnostic threshold for osteoporosis?

Answer 2

> 2.5 SD below mean peak bone mass

Question 3

name some endocrine disorders that can increase risk of osteoporosis

Answer 3

cushing’s
hyperparathyroidism
hyperthyroidism

Question 4

name some GI disorders that can increase risk of osteoporosis

Answer 4

hepatic insufficiency
malabsorption
malnutrition

Question 5

what causes osteomalacia?

Answer 5

vitamin D deficiency

Question 6

how does vitamin D deficiency lead to hypocalcaemia?

Answer 6

vitamin D stimulates absorption of calcium, so lack means less is absorbed

Question 7

what blood results will be abnormal in a patient with osteomalacia?

Answer 7

calcium low

PTH elevated

Question 8

what is avascular necrosis (AVN)?

Answer 8

necrosis of bone and marrow

Question 9

what causes AVN?

Answer 9

loss of vascular supply to the bone

Question 10

name some predisposing factors for AVN

Answer 10

alcohol 
connective tissue disorders 
decompression sickness
sickle cell
infection 
pregnancy 
pancreatitis

Question 11

name two drugs that can increase risk of AVN

Answer 11

corticosteroids

bisphosphonates

Question 12

what is a possible complication of AVN?

Answer 12

secondary OA