Vascular Bone Disorders Flashcards
(25 cards)
where is blood pressure the greatest in bone? order from greatest to least
diaphysis
metaphysis
epiphysis
what does the nutrient artery of bone provide?
marrow, metaphysis, and inner 2/3 of cortex
what does the periosteal vessels provide in bone?
outer 1/3 of cortx
where is nutrient artery located in bone?
oblique canal within the diaphysis
does the nutrient artery or the metaphyseal arteries pierce into the epiphyseal space?
no…they make 180 degree turn
what is first thing to happen with decreased blood flow to bone?
death of marrow elements and osteocytes
how does bone death appear?
loss of osteocytes…empty lacunae
once bone dies, what happens?
revascularization from adjacent viable bone
what does the revascaularization of dead bone cause?
hyperemia and ostopenia of living bone and sclerosis of dead bone
how does sclerosis of bone appear on xray?
super white
what two things can you see on histo with bone death?
cement lines
empty lacunae
once bone is necrotic…what happens?
osteoclasts resorb the dead bone
when dead bone gets resorbed…what does this lead to?
osteoclastic resorption weakens the subchondral bone and you get a collapse at the articular cartilage areas
bone infarcts are called what buzz term on xrays?
smoke up the chimney
what is difference between osteochondrosis and ostenecrosis?
chondrosis is vascular insult to growing bone and necrosis is insult to mature bone
what is name of vascular infarct of metatarsal? which is most common?
freibergs infarctions …2nd metatarsal
what is avascular necrosis of the navicular bone called?
Kohler disease
name four bones common for AVN
talus
scaphoid
lunate
femoral head
what is AVN of the lunate called?
Keinbocks disease
if you suspect scaphoid fracture but do not see it on Xray what should you do for patient?
splint and see back for another xray soon
what is the inherited issue with AVN to femoral head called?
Perthes disease
who gets perthes disease?
ages 5-10
what are common symptoms of osteonecrosis of hip?
pain stiffness limp and mechanical symptoms
name two causes of femoral head AVN other than injury
steroid and alcohol use/abuse
