Mod 8: musculoskeletal disorders Flashcards
Osteoporosis
decreased (3)
risk of
most common bone disease
vMineral density, vStructural integrity, vStrength
risk of bone fractures
Secondary osteoporosis caused by
hormone imbalance, dm, hyperparathyroid, hyperthyroid, heparin, corticosteroids, phenytoin, barbiturate, lithium, tobacco, ethanol, HIV, RA, CKD, liver disease, malabsorption syndromes
normal bone mass
Osteopenia
Osteoporosis
normal >833
osteopenia: 648-833
osteoporosis: <648
Severe osteoporosis
skeleton can’t provide support
spontaneous frx d/t bumps/falls
Bone homeostasis dependent on balance between cytokine receptor activator of ____, its receptor ____ and its decoy receptor _____
nuclear factor KB ligand (RANKL)
its receptor RANK
its decoy receptor osteoprotegerin (OPG)
Osteoblasts express ___ which is necessary for _____ development
RANKL, necessary for osteoclast development
RANKL activates ___ receptor which is expressed on ____
= ____life of osteoclasts
activates RANK receptor which is expressed on osteoclasts
=prolongs life of osteoclasts
Effects of RANKL are mitigated by ____ , prevents it from binding to ____
This process is regulated by __ and ____
OPG
prevent binding to RANK
regulated by cytokines and hormones
____ stimulates OPG secretion and down regulates ____
why are post-menopausal women at risk for osteoporosis
estrogen, down regulates RANKL
post menopausal women have ^RANKL=osteoporosis
_____increases RANKL expression and inhibition of _____ production
Glucocorticoids increase RANKL
inhibit OPG production
age related bone loss occurs from v___, ^____activity, v____ function
vGH, ^RANKL, vOPG
Osteoarthritis= loss of ____ and destruction of ______
can occur due to ___, __, or _____
loss of articular cartilage and destruction of joint capsule
sports, obesity, and chronic disease (DM)
degeneration of articulating cartilage in OA = ^_____of cartilage and loss of _________
eventually requires _____ surgery
^remodeling of joint cartilage and loss of smooth, frictionless joint
eventually requires joint replacement surgery
Sarcopenia- loss of ___mass d/t aging
we lose __% by age 50
declines __% per decade
__% after 80y/o
loss of muscle mass d/t aging
lose 10% by 50y/o
declines 15% per decade
30% after 80 y/o
Muscle ___ declines faster than muscle ___
strength declines faster than mass
In sarcopenia there’s loss of ____fiber and ____cells
loss of type 2 fiber and satellite cells
what contributes to sarcopenia
v___synthesis, v____volume, vSize of _____, shortening ____
vRNA synthesis,
vMitochondrial volume,
vSize of motor units,
shortening telomeres
Duchenne muscular dystrophy ____linked genetic disorder mainly affecting ___
caused by deletion of one or more ___on the ___gene on the Xchromosome
x linked genetic disorder mainly affects boys
caused by deletion of 1+ exons on the DMD gene on X chromosome
Normally DMD gene makes a membrane stabilizing protein called ____ which anchors the ________ of the skeletal muscle to the _______
dystrophin-anchors the actin cytoskeleton of the skeletal muscle to the basement membrane
(absent in dmd)
Lack of dystrophin in DMD allows for ____ to be torn apart during _____
Free ___enters ____ cells and = cell death and necrosis = ^CK
muscle fibers torn durin contraction
free calcium enters muscle cells =^CK
DMD s/s in kids
gait abnormalities (3-4y/o) toe walk can't get up from sitting frequent falls pelvic area muscle weakness, calf muscle hypertrophy
DMD kids will have ___sign
Gowers sign
