O: Metabolic Bone Disease Flashcards
what are the metabolic bone diseases?
osteoporosis, osteomalacia, Paget’s disease
what is osteoporosis?
localised dec of bone mass
types of osteoporosis?
osteopenia, osteoporosis
1y osteoporosis caused by…
idiopathic
2y osteoporosis?
endocrine disorders, GI, drugs
aetiology for osteoporosis
age, physical activity, genetic, Ca deficiency, hormonal effects, endocrine, coeliac
why are middle aged women more at risk of developing osteoporosis?
menopause
what are endocrine causes of osteoporosis
Cushing’s, hyperthyroidism, hyperparathyroidism
why would coeliac’s be a risk factor for osteoporosis
malabsorption of Ca
main drug that predisposes to osteoporosis
corticosteroids
why do corticosteroids cause osteoporosis
reduce osteoclast activity and reduce Ca absorption= red bone mass
how does age cause osteoporosis
reduced proliferation. biosynthetic ability of osteoblasts
what is diagnostic of osteoporosis
< -2.5 SD below peak bone mass
what is dexa bone scan result for osteopenia dx??
-1 to -2.5
lifestyle mx of osteoporosis
strength training- weight bearing exercises
700mg of Ca (1000 for post-menopausal women)
Rx mx for osteoporosis?
Ca and VitD supplements, bisphosphonates, teriparatide (PTH), SERMs
what are SERMs?
selective oestrogen agonists/ antagonists
main osteoporosis complication?
multiple fractures
hyperparathyroidism is a risk factor for?
osteoporosis & Brown tumours
what are Brown tumours?
haemorrhages causing inflammatory cell activation and can become cystic
ix for hyperparathyroidism?
Ca levels, alk phos, PTH
what is the name for osteomalacia in kids?
rickets
what is osteomalacia?
marked softening of bones
aetiology of osteomalacia?
severe VitD deficiency
why does dec VitD cause osteomalacia?
abnormal mineralization of bone matrix
2 biochemical findings of osteomalacia?
hypocalcaemia and elevated PTH
what is Paget’s?
inc bone turnover
pathophysiology of Paget’s?
dec osteoclastic activity, inc osteoblastic activity
___ year group is at risk of Paget’s
late adulthood
two types of Paget’s disease?
monostotic or polystotic
what bones are more at risk of Paget’s?
long bones, pelvis, lumbar spine, skull
T/F: Paget’s occurs in multiple sites
F: sticks to one bone
aetiology of Paget’s- be specific?
genetic (SQSTMI/ p62) and viral (measles)
what are s/s of Paget’s?
pain if nerve compression or fracture, deafness
what are imaging findings of Paget’s?
abnormal shape and inc metabolism of bone
main biochemistry finding of Paget’s?
inc alk phos
necrosis of bone and bone marrow is called…
avascular necrosis
aetiology and pathophysiology of avascular necrosis?
fractures which cause loss of vascular supply to bone
