Mod 8: musculoskeletal disorders

Question 1

Osteoporosis
decreased (3)
risk of

Answer 1

most common bone disease
vMineral density, vStructural integrity, vStrength
risk of bone fractures

Question 2

Secondary osteoporosis caused by

Answer 2

hormone imbalance, dm, hyperparathyroid, hyperthyroid, heparin, corticosteroids, phenytoin, barbiturate, lithium, tobacco, ethanol, HIV, RA, CKD, liver disease, malabsorption syndromes

Question 3

normal bone mass
Osteopenia
Osteoporosis

Answer 3

normal >833

osteopenia: 648-833
osteoporosis: <648

Question 4

Severe osteoporosis

Answer 4

skeleton can’t provide support

spontaneous frx d/t bumps/falls

Question 5

Bone homeostasis dependent on balance between cytokine receptor activator of ____, its receptor ____ and its decoy receptor _____

Answer 5

nuclear factor KB ligand (RANKL)
its receptor RANK
its decoy receptor osteoprotegerin (OPG)

Question 6

Osteoblasts express ___ which is necessary for _____ development

Answer 6

RANKL, necessary for osteoclast development

Question 7

RANKL activates ___ receptor which is expressed on ____

= ____life of osteoclasts

Answer 7

activates RANK receptor which is expressed on osteoclasts

=prolongs life of osteoclasts

Question 8

Effects of RANKL are mitigated by ____ , prevents it from binding to ____
This process is regulated by __ and ____

Answer 8

OPG
prevent binding to RANK
regulated by cytokines and hormones

Question 9

____ stimulates OPG secretion and down regulates ____

why are post-menopausal women at risk for osteoporosis

Answer 9

estrogen, down regulates RANKL

post menopausal women have ^RANKL=osteoporosis

Question 10

_____increases RANKL expression and inhibition of _____ production

Answer 10

Glucocorticoids increase RANKL

inhibit OPG production

Question 11

age related bone loss occurs from v___, ^____activity, v____ function

Answer 11

vGH, ^RANKL, vOPG

Question 12

Osteoarthritis= loss of ____ and destruction of ______

can occur due to ___, __, or _____

Answer 12

loss of articular cartilage and destruction of joint capsule
sports, obesity, and chronic disease (DM)

Question 13

degeneration of articulating cartilage in OA = ^_____of cartilage and loss of _________
eventually requires _____ surgery

Answer 13

^remodeling of joint cartilage and loss of smooth, frictionless joint
eventually requires joint replacement surgery

Question 14

Sarcopenia- loss of ___mass d/t aging
we lose __% by age 50
declines __% per decade
__% after 80y/o

Answer 14

loss of muscle mass d/t aging
lose 10% by 50y/o
declines 15% per decade
30% after 80 y/o

Question 15

Muscle ___ declines faster than muscle ___

Answer 15

strength declines faster than mass

Question 16

In sarcopenia there’s loss of ____fiber and ____cells

Answer 16

loss of type 2 fiber and satellite cells

Question 17

what contributes to sarcopenia

v___synthesis, v____volume, vSize of _____, shortening ____

Answer 17

vRNA synthesis,
vMitochondrial volume,
vSize of motor units,
shortening telomeres

Question 18

Duchenne muscular dystrophy ____linked genetic disorder mainly affecting ___
caused by deletion of one or more ___on the ___gene on the Xchromosome

Answer 18

x linked genetic disorder mainly affects boys

caused by deletion of 1+ exons on the DMD gene on X chromosome

Question 19

Normally DMD gene makes a membrane stabilizing protein called ____ which anchors the ________ of the skeletal muscle to the _______

Answer 19

dystrophin-anchors the actin cytoskeleton of the skeletal muscle to the basement membrane
(absent in dmd)

Question 20

Lack of dystrophin in DMD allows for ____ to be torn apart during _____
Free ___enters ____ cells and = cell death and necrosis = ^CK

Answer 20

muscle fibers torn durin contraction

free calcium enters muscle cells =^CK

Question 21

DMD s/s in kids

Answer 21

gait abnormalities (3-4y/o)
toe walk
can't get up from sitting 
frequent falls 
pelvic area muscle weakness, calf muscle hypertrophy

Question 22

DMD kids will have ___sign

Answer 22

Gowers sign