Metabolic & Vascular

Question 1

What hormones regulate calcium homeostasis?

Answer 1

PTH

Vitamin D3

Question 2

What does vitamin D do?

Answer 2

increases Ca absorption

Question 3

What mineral is involved in the release of PTH?

Answer 3

Mg

Question 4

What effect does vitamin D have on PTH?

Answer 4

inhibits release

Question 5

What bone cell has PTH receptors? Function?

Answer 5

osteoblasts

activates osteoclasts via RANK

Question 6

What is the function of PTH in the kidney?

Answer 6

get rid of phosphate

Question 7

What are the symptoms of hypercalcemia?

Answer 7

stones
groans
bones
psychiatric overtones

Question 8

What 5 metabolic diseases affect bone?

Answer 8

primary/secondary hyperparathyroidism
osteomalacia
Rickets
renal osteodystrophy

Question 9

What is the most common cause of osteomalacia?

Answer 9

vitamin D deficiency

Question 10

What is the difference between Type 1/2 hereditary vitamin D deficiency?

Answer 10

1: defect of hydroxylase, resolves with supplementation
2: receptor defect, needs high dose supplementation and Ca

Question 11

What is Rickets?

Answer 11

osteomalacia in growing bones

Question 12

What is wrong in osteoporosis?

Answer 12

decreased bone quantity with normal mineralization (less trabecular bone)

Question 13

How does osteoporosis present?

Answer 13

pathologic fracture (proximal femur, distal radius, vertebral)

Question 14

What is osteogenesis imperfecta?

Answer 14

type 1 collagen defect

Question 15

What is osteopetrosis?

Answer 15

osteoclast failure with very high density bone

Question 16

What is Paget disease?

Answer 16

overfunction of osteoclasts

high rate of bone turnover

Question 17

What are the stages of decreased bone circulation?

Answer 17

death of marrow and osteocytes
disappearance of osteocytes
revascularization
sclerosis/osteoporosis from hyperemia
resporption of necrotic area
weakened bone

Question 18

What is osteochondrosis?

Answer 18

vascular insult to growing bone leading to necrosis of epiphysis and closure of growth plates

Question 19

Why does hip pain refer to the knee?

Answer 19

obturator nerve

Question 20

Which bones are at risk of AVN?

Answer 20

femoral head
talus
lunate
scaphoid

Question 21

What bone is involved in Keinbock’s disease?

Answer 21

lunate

Question 22

Why is scaphoid injury a significant cause of morbidity?

Answer 22

wrist arthritis

Question 23

What is Perthes disease?

Answer 23

AVN of femoral head in kids

Question 24

What are the possible etiologies for AVN? (7)

Answer 24

steroids
alcohol
trauma
decompression disease
Perthes
Gaucher (storage disease)
idiopathic