osteoporosis Flashcards
what are some signs of osteoporosis
- shortened stature
- kyphosis or lordosis
- bone pain or fracture
what are the functions of osteoblasts and osteoclasts
Osteoblasts: synthesize osteoid which becomes bone
osteolclasts: cells that reabsorb bone under influence of parathyroid hormone
how is osteoclast formation regulated
Osteoblast also secrete osteoprotegerin [OPG] which acts as a receptor for RANKL preventing it from binding to the RANK receptor on Preosteoclasts.
OPG prevents bone resorption by inhibiting osteoclast differentiation.
whats the difference between osteopenia and osteoporosis
osteopenia refers to decrease bone mass, and osteoporosis is defined as osteopenia that is severe enough to the significantly increase the risk of fractures.
who does primary osteoporosis affect most and why
It is a disease of old age
It affects women more often than men
In women it is seen after menopause
what causes secondary osteoporosis
occurs at any age and cause by
- Diabetes, type 1
- Malabsorption,MalnutritionVitamin C, D deficiencies
- alcohol and chemotherapy
- anemia
whats the difference between older and younger osteoblasts
Osteoblasts from older individuals have reduced proliferative and biosynthetic potential when compared with osteoblasts from younger individuals.
how do we define senile osteoporosis
this is age related as the older we get the ability of our osteoclasts to produce dense bone deminishes.
does reduced activity affect bone formation
Reduced physical activity increases the rate of bone loss
what nutritional deficiency will cause osteoporosis
Calcium deficiency, increased PTH secretion and reduced levels of vitamin D may also contribute to the development of senile osteoporosis later in life.
how do hormones control bone formation in post menopausal women
decrease in estrogen leads to increase of inflam cytokines, this stimulates osteoclast recruitment and activity by increasing RANKL and decreasing OPG cytokines associated: IL-1 IL-6 TNF
morphologically how does senile osteoporosis affect the bones
the cortex is thinned by subperiosteal and endosteal resorption and the Haversian systems are widened.
clinically what do vertebral fractures cause
cause back pain, when multiple, can cause significant loss of height and various deformities, including lumbar lordosis and kyphoscoliosis (Dowager’s spine)
what is a colles fracture
Fractures of the distal radius
what are the risk factors of osteoporosis
A- alcohol use C- corticosteroid use C- calcium low E- estrogen low S- smoking S- sedentary life
