Osteoporosis Flashcards
Osteoporosis
“Porous bone”
Decreased bone mass and increased risk of fracture
Osteopenia vs osteoporosis
Osteopenia: bone thinning/loss
Osteoporosis: severe bone/loss
Marked by increase risk of fracture with minimal trauma
Normal bone turnover
5% of adult bone is actively being remodeled
Age 30 is the age where osteoclast activity outpaces osteoblast activity
what is the main fuel of osteoclast activity?
RANKL activity fuels roughly 90% of osteoclast activity
increases are common after menopause for women
Dowingers hump/ hunchback
Colloquial terms for increased osteoclast activity in the thoracic region increasing thoracic kyphosis
Decrease in what hormone increases RANKL activity?
Estrogen
What are the percentages of women with prevalence osteoporosis at ages 70, 80 and 90 respectively?
20%, 40%, 66%
What is the chance of women and men greater than 50 will develop an osteoporotic fracture
1/2 in women
1/5 in men
Levels of Hormones that influence increased osteoporosis prevalence
PTH increase
Decreases in Estrogen and testosterone
Thyroxine increase
Why is osteoporosis known as a “silent” disease?
Asymptomatic and no physical exam findings until fractures occur
Most common fractures in osteoporosis
Vertebral fractures (most common)
Hip fractures
Collies fractures
Heel ultrasound pros and cons
Tests for osteoporosis
Pros:
Cheap portable and no radiation, good specificity
Cons:
Low sensitivity, Tscore isn’t accurate
FRAX score
Screening tool that Predicts osteoporotic risk
Tests 11 risk factors but is not very sensitive and specific
QFracture questionare
Osteoporosis screening tool that assess for 24 risk factors
DEXA use
Measures bone density typically at hip and spine
For each 1 SD drop in bone density = 2.6x increase fracture risk
what T-scores signal risk for osteoporosis?
Normal = 0 to -1.0
Osteopenia = -1.0 to -2.49
Osteoporosis = < -2.5
Treatment for osteopenia
Meds not recommended just monitor unless FRAX score is higher than 3%
Treatment of osteoporosis
Meds recommended if DEXA score = -2.5 or worse and have experienced a osteoporotic fracture
Bisphosphonates
Potent anti-resorption bone meds.
Should not take after 3 years since it can eventually increased bone density beyond normal levels
Side effects: GI distress, osteonecrosis of the jaw and increased femoral fractures
Selective Estrogen Receptor Modulators (SERMs)
Mimic to estrogen and limits RANKL numbers. Decreases risk of spinal fractures
Also decreases uterine and breast cancers
First one discovered = Tamoxifen
Side effects: headaches, flushing, possible DVTs
Human Monoclonal Antibody (Denosumab)
RANKL inhibitor decreasing osteoclast activation.
Marked decrease in risk of spine/hip/wrist fractures
Is one of the only treatments of osteoporosis that is safe with impaired renal functions
Side effects: nausea, hypocalcemia, osteonecrosis of the jaw
Calcitonin
Inhibits osteoclast activity by decreasing PTH activity. Causing increased OPG release from osteoblasts
Decreases bone pain in acute fractures.
Not a 1st line therapy since it is not very effective long term
Side effects: hepatic cancer, hypersensitivity, hypocalcemia, epistaxis
