Disorders of Bone

Question 1

osteoperosis

Answer 1

bone density decreased due to reduced osteoblast activity, results in reduced bone mineral density and inc porosity

• brittle bones which fracture easily

Question 2

biochemistry of osteoperosis

Answer 2

normal

Question 3

where are osteoblasts present in bone

Answer 3

on the surface - in periosteum

Question 4

what is osteoperosis screened for using

Answer 4

DEXA bone scan

Question 5

what is fracture risk in osteoperosis screened for with

Answer 5

FRAX score

Question 6

management of osteoperosis

Answer 6

biphosphonate - inhibit osteoclast activity

calcium and vitamin D supplements

Question 7

type 1 osteoperosis

Answer 7

post menopausal - inc osteoclastic activity

Question 8

type 2 osteoperosis

Answer 8

of old age, steroids, alcohol, malnutrition, RA

Question 9

osteomalacia

Answer 9

(rickets in children)

qualitative defect characterise by abnormal softening of the bone due to deficient mineralisation of osteoid

2y to inadequate calcium and phosphorus

Question 10

what is the PC of osteomalacia

Answer 10

bone pain and muscle weakness

Question 11

biochemistry of osteomalacia

Answer 11

Lowered Ca²⁺ and phosphate, raised ALP and PTH.

Question 12

paget’s disease

Answer 12

increased osteoclastic activity results in a compensatory increase in osteoblastic activity - increased bone turnover

new bone is disorganised and predisposed to fracture

Question 13

biochemistry of Paget’s disease

Answer 13

normal apart from raised ALP

Question 14

PC of Paget’s disease

Answer 14

70-90% asymptomatic

may be bony pain from microfracture

Question 15

treatment of Paget’s disease

Answer 15

biphosphonates (inhibit osteoclast activity)

Question 16

primary hyperparathyroidism

Answer 16

high levels of PTH due to parathyroid adenoma or hyperplasia of parathyroid gland

Question 17

biochemistry of primary hyperparathyroidism

Answer 17

increased Ca²⁺ and ALP, markedly increased PTH, lowered phosphate

Question 18

secondary hyperparathyroidism

Answer 18

compensatory high parathyroid activity due to low calcium

Question 19

biochemistry of secondary hyperparathyroidism

Answer 19

decreased Ca²⁺, increased phosphate, aLP and PTH

Question 20

clinical features of secondary hyperparathyroidism

Answer 20

bones - fracture, osteoperosis, muscle fatigue

stones - kidney disease, gallstones

groans - nausea, constipation, peptic ulcer disease

psychiatric moans - depression, lethargy and seizures