Bone DIsease Flashcards
what is arthritis
inflammation of joints
what is arthrosis
a non-inflammatory joint disease
what is arthralgia
joint pain
describe bone
mineralised connective tissue
what are the three features of bone
load bearing
dynamic
self repairing
what does dynamic mean with bone
bone is constantly changing and remodelling - allows bone to adapt
what is bone removed by
osteoclasts
what is bone deposited by
osteoblasts
what three substances are needed in the correct amount for bone remodelling
calcium
phosphate
vitamin D
what forms a store for calcium
bone
where does exchangeable calcium move from
from the bone to the ECF and eventually to the gut
how is calcium in the body lost
through the gut and through the urine
why is it so important for calcium to be kept at a constant level in the blood
calcium is involved in nerve and muscle function
what two aspects work to produce the correct location for calcium
bone and ECF work together and parathyroid hormone
what are the three main actions of parathyroid hormone
maintains serum calcium levels
increases calcium release from bone
reduces calcium excretion
what is hypoparathyroidism
low serum calcium
what is primary occurrence hyperparathyroidism
due to a gland dysfunction (tumour)
high serum calcium results
what is secondary occurrence hyperparathyroidism
low serum calcium causes parathyroid hormone to be high and activates osteoclasts in the bone to maintain serum calcium level
what does hyperparathyroidism result in
increased bone resorption
how is vitamin D produced
from sunlight to cholecalciferol in the skin
what is the active component of vitamin D that is absorbed in the gut
dihydroxycolecalciferol
what can cause patients to have decreased vitamin D levels
low sunlight exposure
poor GI absorption
drug interactions
which drugs can interact and cause low vitamin D levels
antiepileptic drugs
carbamazepine, phenytoin
what is osteomalacia
normal amounts of matrix but has not been mineralised correctly
poorly mineralised osteoid matrix
poorly mineralised cartilage growth plate
what occurs if there is poorly mineralised osteoid matrix and cartilage growth plate during bone formation
rickets
what occurs if there is poorly mineralised osteoid matrix and cartilage growth plate after bone formation completed
osteomalacia
what is osteomalacia related to
calcium deficiency - serum calcium preserved at the expense of bone
what are the bone effects of osteomalacia
bones bend under pressure
bow legs
vertebral compression in adults
bones ache to touch
what are four effects of hypocalcaemia
muscle weakness
trosseau and chvostek signs positive
carpal muscle spasm
facial twitching from VII tapping
how is osteomalacia treated
by correcting the cause
controlling GI disease and restoring adequate calcium to diet
sunlight exposure
dietary vitamin D
what is osteoporosis
the loss of bone mineral and matrix giving a reduced bone mass
a reduced quantity of normally mineralised bone
what are some risk factors for osteoporosis
age
female sex
endocrine
genetic
what aspects of endocrine function could put you at higher risk of developing osteoporosis
osetrogen and testosterone deficiency
cushings syndrome
what patient and medical factors can increase risk of osteoporosis
inactivity
smoking
excessive alcohol use
poor dietary calcium
steroid
antiepileptics
what causes bone mass loss rate in women in the menopause to increase
oestrogen withdrawal
what are effects of osteoporosis
increased bone fracture risk
height loss
kyphosis and scoliosis
nerve root compression
how can osteoporosis be prevented
exercise
high dietary calcium intake
oestrogen hormone replacement therapy
osteoporosis prevention drugs - bisphosphonates
what two ways can hormone replacement therapy occur
oestrogen only
combined
what is the benefit of oestrogen only replacement drugs
reduces osteoporosis risk
what are disadvantages of oestrogen only replacement drugs
increased breast cancer risk
increased endometrial cancer risk
increased DVT risk
what are examples of non-nitrogenous bisphosphonates
etidronate
clodronate
tildronate
what are examples of nitrogenous bisphosphonates
pamidronate
alendronate
olpadronate
what is the effectiveness of bisphosphonates
reduces vertebral fracture
reduces other fractures
can be combined with HRT
benefit lost if drug is discontinued
