Bone/Joint Disorders - textbook Flashcards
osteoporosis
common & often silent disorder causing significant morbidity and mortality and reduced quality of lif
osteoporosis: characterized by
low bone density
loss of bone strength resulting in an inc risk & rate of bone fx
risk of developing osteoporosis
-age (inc after 50)
-sex (African Americans have the highest BMD, while Asian Americans have the lowest)
-race/ethnicity (white, old women have the highest %)
-common sites of fx: spine (kyphosis), hip, wrist but all can be affected
moat common skeletasl disorder
osteoporosis
osteoporosis classified as
primary (no known cause) - most often: postmenopausal women & aging men
secondary (caused by drugs or other diseases)
why do postmenopausal women have accelerated bone loss?
loss of estrogen
secondary causes of osteoporosis
such as hypogonadism, are found more commonly in men with low trauma fractures
osteoporosis is known for
an imbalance in bone remodeling (accelerated w/ decreased estrogen in the first 5 years)
osteoclastic activity is enhanced, resulting in overall bone loss
BMD
low bone mineral density
diagnosis osteoporosis
-assessment of BMD
-vertebral imagining
-labs
-other factors for secondary causes
-biochemical markers for bone turnover
measuring BMD
dual-energy x-ray absorptiometry (DXA) (WHO recommended) to measure central (hip and/or spine) and peripheral (heel, forearm, or hand) sites: peripheral quantitative computed tomography, radiographic absorptiometry, single-energy x-ray absorptiometry
T-scores & Z-scores: indicating osteoporosis
T-score more than –2.5 standard deviations below the mean BMD in young adults
osteopenia
low bone mass, is defined as a T-score between –2.5 and –1.0
National Osteoporosis Foundation (NOF) and AACE recommend BMD measurements in the following groups
women age 65 and older, men age 70 and older, perimenopausal women and men age 50 to 69 with risk factors, anyone with a fracture after age 50, and adults with a secondary cause for osteoporosis
vertebral imagining is recommended in patients with a central T-score:
–1.0 or less and at least one other factor:
(a) women age 70 and older and men age 80 and older
(b) reported decrease in height of 4 or more centimeters
(c) reported or documented prior vertebral fracture
(d) glucocorticoid therapy of at least 5 mg daily of prednisone (or equivalent) for at least 3 months
screening labs:
-complete blood count cell
-serum chemistries (electrolytes w/ calcium, phosphorus, liver enzymes)
- vit D
-urinalysis
monitoring bone turnover markets (BTMs)
c-terminal telopeptide (CTX) for bone resorption
serum carboxy-terminal propeptide of type I collagen (PINP) for bone formation
nonmodifiable risk factors
-family hx
-age
-ethnicity
-sex
-concomitant disease states
-smoking
-low calcium intake
-poor nutrition
-inactivity
-heavy alcohol use
-vit D deficiency
prevention should start at an early age
calcium supplement doses should be limited to
500-600mg per dose
calcium carbonate
take w/ food to maximize absorption
-pts taking PPI/h2RAs difficulty absorbing due to reduced stomach acidity
calcium citrate
do not need an acid environment for absorption
-taken w/ or w/o food