Lecture 28-Bone Health, Falls and Fractures Flashcards
by what age is the skeleton completely hardened
25
how many bones are in the human body
206
Osteoclasts and osteoblasts
Osteoclasts tear down and osteoblasts build bone throughout the lifespan with the processes of resorption and deposition
bone resorption is the action of what
osteoclasts and parathyroid hormone
bone deposition is the action of what
osteoblasts and calcitonin
bone resorption and bone deposition is regulated by
thyroid and parathyroid glands
an osteoblast ….
forms new bone tissue
an osteoclast …..
breaks down old bone tissue
what plays vital roles in bone development, growth and repair
vitamin A, vitamin D, calcium and other hormones
rates of bone growth is highest when
infancy and pubertal growth spurt
velocity of bone growth doubles when
adolescence critical period
~40% of peak bone mass is laid down when
end of puberty
at age 20 what % of peak bone mass is attained
90-95%
what happens to bone mass after your mid 30s (also how does men and women bone mass change throughout their life)
you begin to slowly lose bone mass
women lose bone mass faster after menopause, but it happens to men too
what are the determinants of bone strength
- bone mineral density
- geometry
what is the most important effect of stress on the bone and what is this
strain
measurement of deformation of bone to external load
what is said about your ground reaction forces if you are lighter
the lighter you are the smaller your ground reaction forces are
peripheral skeleton bone strength is positively associated with what
total and dairy protein intake in healthy postmenopausal women
In elderly there is
- inadequate intake of protein
- reduced ability to use available protein
- greater need for protein
In elderly
- inadequate intake of protein
- reduced ability to use available protein
- greater need for protein
leads to what
loss of functionality
muscle
bone
immune system
what is the strategy to maximise and protect bone mass in children
achieve peak bone mass
what is the strategy to maximise and protect bone mass in adults
maintain bone mass
what is the strategy to maximise and protect bone mass in older adults
slowing bone loss
reducing falls and fractures
osteoporosis NZ estimates how many older kiwis have broken a bone since their 50th birthday
> 180,000
annually how many people sustain a hip fracture, and how many are admitted to hospital with other fractures
~3,700 hip fractures
~13,800 admitted to hospital with other fractures
what are the three types of osteoporosis
age associated / post menopausal
idiopathic
secondary
what are the risk factors of osteoporosis
-age
-genetics
-sex
-physical activity
-Diet
-Hormones
what are some diseases / genetics that are considered secondary risk factors for osteoporosis
-multiple myeloma
-metastatic bone cancer
-rheumatoid arthritis
-pagets disease
what % of hip fractures are due to falls
> 95%
what is the 5th leading cause of death in older adults
falls
what are some risks for falls in older adults
-muscle weakness
-poor balance / physical activity
-poor eyesight
-benzodiazepine use
what are the risks for fractures in falls for older people
- failure to break a fall
- falling to the side
- age : increased risk of osteoporosis
- low bone mass
a prior fracture at any skeletal sight does what
doubles future fracture risk
what does sarcopenia and osteoporosis lead to increased likeliness of
fracture
2nd fracture often
happens within 6-8 months
does NZ have strength and balance programs to prevent falls in elderly
yes
Vitamin D has an important role together
with calcium in mineral metabolism and bone growth and maintenance
trials show what about vitamin D supplements and bone density
vitamin D supplements found to increase bone density
what is found from clinical trials about vitamin D supplements and non skeletal endpoints
not demonstrated benefits on muscle mass or function
calcium supplements in healthy individuals are ……
not needed
nor required in most people receiving treatment for osteoporosis
vitamin D supplementation is / isnt found to reduce risk of fractures
isnt
the findings of vitamin D supplementation not being effective may not apply to ….
individuals with very low 25(OH)D levels, gastrointestinal disorders causing malabsorption or those with osteoporosis
sarcopenia increases risk of ….. and osteoporosis increases risk of ….
sarcopenia increases risk of falls and osteoporosis increases risk of fractures
they both link together
sarcopenia and osteoporosis share
an underlying pathology
Prevelance of osteoporosis was higher in
sarcopenia than in non-sarcopenic individuals
co-occurrence (osteosarcopenia) is common and associated with a
higher degree of malnutrition than osteoporosis or sarcopenia alone
