Case of Crumbling Spine Flashcards
fragility fracture?
fracture caused by a fall rom a standing height or less or a spontaneous fracture
Why do people have fragility fractures?
reduced bone mineral density, altered bone architecture
why does bone quality change?
mutations in type 1 collagen, altered hydroxyapatite crystal structure, advanced glycation end products in diabetes
what would drive bone breakkdown?
osteoblast have rank ligand which binds to rank receptor on osteoclast precursor causing mature osteoclast
osteoprotgerin can bind to rank ligand and reduce its activity
what happened after they found out osteoprotogerin function?
denosumab 60mg s/c, igG2 isotype which bind to rank ligand so prevents osteoclast activity
denosumab is cleared through?
reticuloendothelial system
sclereosteosis?
SOST gene mutation- thick bones
sclerosteosis work by?
sost gene is osteocytes causes sclerostin which inhibits WnT signalling and so reduces osteoblast activity
what does romosozumab do?
binds to sclerostin and so WnT signalling system remains active and so increased osteoblast activity
how to reduce skeletal aging?
senescent immune cells accumulate in bone marrow and secrete grancalcin, which represses osteogenesis and promotes adipogenesis via plexin b2 in BMSCs
grancalcin neutralising antibody
systematic review
maximally informed and minimally biased clinical decision making
protocol should be developed?
before, detailing rationale, hypothesis and planned methods
review question
PICO- quantitative/ intervention
SPIDER- qualitative
TYPE 1/2 Osteoporosis?
type 1- post menopausal
type 2 senile
secondary osteoporosis due to?
rheumatois, anorexia, steroids, aromatase inhibitors, PPi, thyroxine, anti-epileptics
Bone mass relies on?
oestogren levels, calcium and vitamin d, PTH
clinically relevant skeletal sites?
spine l1-l4
left hip
right forearm
what is t score?
difference measured BMD and that of a young healthy adult
what is z score?
difference in measured BMD and healthy adult of same age
osteoporosis WHO defintion?
BMD of 2.5. SD or more below the mean peak bone mass average for healthy young adults as measured by DEXA
for postmenopausal women and men over 50 use t score?
normal= equal or greater than -1
osteopenia= -1 and -2.5
osteporosis equal or below -2.5
what does FRAX calculate?
10 year probability of hip fracture or major osteoporotic fracture
cross over vs parallel?
parallel- test drug/ placebo
cross over- swap assigned treatments
interventional?
investigation drug or not for indication
double dummy?
fake tablet/ fake inhaler
relative risk?
risk of an event in active group/ risk of an event in the control group
