BONE DISEASES Flashcards
What is arthritis?
Inflammation of joints
What is arthrosis?
non-inflammatory joint disease
what is arthralgia?
joint pain
what cells cause removal of bone?
osteoclasts
what cells cause deposition of bone?
osteoblasts
what are the three aspects that are crucial in good bone formation?
- calcium
- phosphate
- vitamin D
how is parathyroid hormone related to calcium?
- It maintains serum calcium level (if calcium levels fall, parathyroid hormone levels increase)
- increases calcium release from BONE
- reduces renal calcium excretion
if a patient suffers from hypoparathyroidism, what may their calcium levels look like?
low serum calcium
what do primary and secondary hyperparathyroidism both result in?
increased bone resorption
how is vitamin D related to bone health?
vitamin D allows calcium absorption in the gut
why might a person have low vitamin D levels?
- low sunlight exposure
- poor GI absorption
- drug interactions
what drugs can reduce vitamin D levels?
Antiepileptic drugs:
- carbamazepine
- phenytoin
what is osteomalacia?
Normal amounts of osteoid HOWEVER:
- poorly mineralised osteoid matrix
- poorly mineralised cartilage growth plate
what is osteoporosis?
Loss of mineral and matrix
- reduced bone mass
if osteomalacia occurs during bone formation what is this known as?
RICKETS
what are rickets and osteomalacia both related to?
calcium deficiency
what are some features of osteomalacia?
BONE EFFECTS
- bones bend under pressure (bow legs in kids, vertebral compression in adults)
- bones ache to touch
HYPOCALCAEMIA EFFECTS
- muscle weakness
- Trousseau & Chvostek signs positive
how is osteomalacia managed?
Correct the cause!
- malnutrition = control GI disease
- sunlight exposure = 30 mins x 5 weekly
- dietary = vit D supplements
what are some generalised risk factors that make a patient more likely to develop osteoporosis?
- AGE
- female
- Cushing’s syndrome
- family history
- race = caucasian and asian women
- early menopause
what are some patient specific factors that can contribute to osteoporosis?
- inactivity
- smoking
- excess alcohol use
- poor dietary calcium
what medications can contribute to development of osteoporosis?
steroids & antiepileptics both affect Ca levels
at what age does a person have peak bone mass?
between 24-34 y/o
what % of women suffer from osteoporosis at age 50?
15%
what % of women suffer from osteoporosis at age 70?
30%
what % of women suffer from osteoporosis at age 80?
40%
why might women be at a higher risk than men of developing osteoporosis?
- males have higher peak bone mass
- oestrogen withdrawal increases bone mass loss rate in women (eg menopause!)
what are the effects of osteoporosis?
- increased bone fracture risk
- height loss
- kyphosis (spine bends forwards)
- scoliosis
- nerve root compression (back pain)
how can osteoporosis be prevented?
- build maximal peak bone mass (exercise & high calcium intake)
- reduce rate of bone mass loss (continue exercise)
- reduce hormone related effects e.g oestrogen hormone replacement therapy
what might women suffering from menopause related osteoporosis do to prevent/help them?
use HRT (hormone replacement therapy)
what are the effects of HRT?
- reduced osteoporosis risk
- increased breast cancer risk
- increased endometrial cancer risk
- increases DVT risk
- may reduce ovarian cancer risk
what ‘osteoporosis prevention’ drugs may be used?
BISPHOSPHONATES
- non-nitrogenous
- nitrogenous
what are examples of non-nitrogenous bisphosphonates?
- etidronate
- clodronate
- tildronate
