Chapter 44 Flashcards
What is osteopenia?
Lower bone mineral density, common to all metabolic bone diseases (determined with X-ray)
What is osteopenia due to?
Decrease formation, deossification, and mineralization
What is osteoporosis?
Decreased bone density and strength (matrix is weakened and mineralization is decreased)
What are causes of osteoporosis?
UKE, but imbalance between breakdown and formation. (bone breakdown exceeds formation)
What is osteoporosis associated with?
Gender (post menopausal, male hormone decline)
Genetics
Activity level (strain on bones =strength)
Nutrition
Body size
Race
Age related changes (decreased osteoblast replication, change in activity)
There are many secondary causes of osteoporosis. Name a few and how they work.
Hyperparathyroidism: pth increases blood calcium
Alcoholism: stops osteoblasts
Antacids with aluminum: increases calcium excretion
Osteoporosis fractures are due to
loss of trabecular from cancellous bone and thinning of the cortex
What happens in post menopausal osteoporosis ?
Osteoclastic activity increases resulting in a loss of trabeculae
What happens in senile/age related osteoporosis?
Haversian widens because trabeculae is lost
What are manifestations of osteoporosis?
Silent disorder, sudden onset of a fracture, wedging or collapse of vertebrae (loss of height= kyphosis or dowager hump)
What is female athlete triad?
Eating disorder with excessive amount of exercise (decrease in calcium intake, decrease fat to muscle ratio)
In female athlete triad what does it lead to?
Decreased gonadotropic hormone (decreased amount of estrogen), Amenorrhea, and osteoporosis
What is osteomalacia?
Adult condition where there is softening of bones d/t inadequate mineralization
What are manifestations of osteomalacia?
Bone pain, tenderness, fractures, muscle weakness (early sign), delayed healing of fractures with deformities, hyperparathyroidism d/t low calcium levels
What are causes of osteomalacia?
Insufficient Ca absorption (lack of intake, Vit D def) Phosphate defieciency (renal losses, poor absorption in GI tract) Anticonvulsant use (decreases the activation of Vit D)
A form of osteomalacia is renal rickets. What is this?
Occurs with chronic renal failure. The kidneys are unable to activate Vit D and excrete phosphate
A form of osteomalacia is Vit D resistant rickets. What is this?
Genetic renal tubular defect. Occurs in boys>girls
What is rickets?
Childhood disease
Failure/delayed calcification of growth plate= overgrowth
There is an inadequate calcium absorption and lack of Vit D
Metaphyseal regions of long bones widen/deform
What are the causes of rickets?
Nutritional deficits (decreased sunlight, Vit D, Ca, phosphate), kidney failure (decrease Vit D), malaborption, medications, genetics
What are 3 risks for getting rickets?
Breast fed only, dark skinned, decrease sunlight