Bones Flashcards
When do women start to lose more bone loss?
postmenopausal
osteoporosis
Bone density 2.5 standard deviations below peak bone mass
- actual breaks in the trabecular matrix
Osteopenia
thinning trabecular matrix of bone; btwn -1 and -2.5 standard deviations below peak bone mass
Severe osteoporosis
osteoporosis with history of a FRAGILITY fracture
How is osteo diagnosed
DEXA scan; measure with T score
Char of osteoporosis
- low bone mass
- microarchitecture deterioration
- bone fragility and sus to fractures
- structural deterioration
- low bone mass
- ACTUAL breaks in the trabecular matrix
Risks for osteoporosis
aging, white or asian, fem, hx of frac as an adult, fam hx (first degree), low body weight (under 127 lb), smoking, alcohol , steroids
Smaller risk for osteo
thin frame, lack weight bearing exercises, lack Ca on vit D, ED, gastric bypass, lack est and T, excess caffeine
Osteo patho
- inc bone resorption, dec living tissue, inc osteoclast activity
- dec bone formation and dec osteoblast
- can’t make new bone and too much bone resorption
CM of osteoporosis
- none early
- later - fracture, pain, lose height, kyphosis, HIP FRACTURES
Comps of hip fracture
Clots, PNA, sepsis
- inc risk of mortality!
- often proximal third of femur
High risk for hip fractures
65+ and female
CM of hip fracture
Sudden hip pain before or after a fall
- can’t walk
- severe groin pain–displaced fracture, ext rotate and shortened leg
- tender
- little bruise bc encapsulated
- insuff or fragility frac
- no obvious hx but vague knee, butt, groin, or thigh pain
Best tx for osteoporosis
Prevent fractures
Primary prevention of osteoporosis
- Ca supp
- vit D to inc Ca abs
Two pharm methods to tx osteoporosis
inc formation or dec resorption
Which drugs are not used much anymore for osteoporosis?
HRT (bc risk of clots and cancers) and calcitonin (less effective)
Fracture
Any break in bone from more stress than the bone is able to absorb
Causes of fractures
Trauma (fall), muscle ctx, pathologic (weakness), endurance fatigue, repeated stress
Open fractures
aka compound fractures
- break in skin
Closed fractures
aka simple fracture
- no break in skin
transverse fracture
straight line, 90 degree horizontal
spiral fraction
twisted shape
comminuted fraction
more than two frac line or broken into at least 3 places
Impacted fraction
from heights
greenstick fraction
bone bends (in kids)
CM of fractures
Pain
Edema
Deformity
What to do when fracture occurs
try to keep straight and go to ED
Phases of bone healing
- inflam (hematoma)
- reparative (fibrous cartilage and callous, ossification)
- remodeling
delayed healing of fractures (3 types)
- 3M to 1Y post-frac
- delayed union–bone pain and tenderness
- malunion–uneven stress causes improper alignment
- nonunion–no heal w/i 4-6M due to poor blood supply, DM, or stress
Risks for delayed healing
tobacco, old, anemia, uncontrolled DM, low vit D, hypothyroidism, poor nutrition, infx, comp breaks
Common population and cause of impaired bone growth
- kids
- frac in epiphyseal plate–delayed growth
- can delay future bone growth
Compartment syndrome
- inc pressure w/i limited space causes compressed nerves and vessels, necrosis and pain
- tourniquet effect causing edema at the frac site and pressure on soft tissue (tissue hypoxia of muscle and nerve)
what type of injuries cause compartment syndrome
crush injuries, too tight cast, bleed/swell in cast
sx of compartment syndrome
RAPID edema, PAIN, loss or weak pulse
tx for compartment syndrome
Fasciotomy - pack and let ooze
Fat embolism
- fat mol from marrow traumatized tissue breaks free from LONG BONE fracture and travels to the lungs and block BV
- fine to resp dep QUICK
Fat embolism CM
hypoxemia, dec LOC, petechiae (fat mol in capillaries), and rash (last)
Fat embolism tx
Supportive, embolism is self-limiting if can sustain life
- may need ecmo or vent
Osteomyelitis
- acute or chronic pyogenic infx of bone
- from bac - S. aureus trapped in skin
Osteomyelitis patho
- pressure inc on the bone
- local artery collapses
- dec access of oxygen, nutrients, immune cells and ABX
- impaired healing
Risks for osteomyelitis
Recent trauma, DM, IDU, HD, splenectomy
Osteomyelitis CM
- local tenderness, redness, drainage, dec mvt, spontaneous frac
- systemic fever, pos blood, leukocytosis
Tx for osteomyelitis
- positive blood culture
- Nafcillin, cefazolin, vanc
- empiric abx (continuous or infused with abx)
- bacteria-specific
- may be 2W IV or 2 oral or longer
Routes of contamination for osteomyelitis
Direct–open wound - frac, shot, stab, surgery (sternotomy)
Indirect–bloodstream infx to bone, bacteremia
