ISCD Exam Study Set/ ISCD Exam Ques ons and answers
Newest RATED A+ 2025/2026 NEW!!
state the defini on of osteoporosis - Ans NEWEST DEFINITION: "osteoporosis is a skeletal
disorder characterized by compromised bone strength predisposing to an increase risk of
fracture. bone strength reflects the integra on of two main features: bone density and bone
quality"
Osteoporosis can also be defined based on the presence or history of a low-trauma or fragility
fracture
-2.5 T score or below
what is a fragility/low trauma fracture - Ans a fracture resul ng from the force of a fall from a
standing height or less; or a bone that breaks under the condi ons that would not cause a
normal bone to break
summarize the pathophysiology of osteoporosis - Ans bone loss occurs when resorp on
exceeds forma on - this can happen due to a number of things; age related bone loss, disease
related to bone loss (ex: malabsorp on diseases like certain cancers), menopause, lifestyle, etc.
as bone loss occurs, there is loss of quality as well as quan ty. WHO classifies osteoporosis as -
2.5 or below T-score.
what is the defini on of prevalence - Ans frequency of disease at a specific point in me ("30%
of women over age 50 have osteoporosis")
what is the defini on of incidence - Ans new cases of disease over a specific period of me
("the incidence of hip fractures in an elderly popula on is 12 per 1000 person-years")
,explain the prevalence and incidence of osteoporosis and fractures - Ans prevalence of
osteoporosis: es mated 200 million people have osteoporosis worldwide
incidence of osteoporosis: hip fracture projected to increase 240% in women and 320% in men
by 2050
in women, the incidence of clinical vertebral fractures begins to increase around age 55-60 and
rises linearly (5-10 yrs later for men)
in women, the incidence of hip fractures begins to raise about age 65 and increases
exponen ally (5-10 yrs later for men)
distal forearm fractures - mortality and morbidity - Ans third most common osteoporo c
fracture
risk increases early in women (age 45-50) and levels off 60-65
most likely caused by fall on outstretched hand
vertebral fracture - mortality and morbidity - Ans VERTEBRAL FRACTURE IS THE MOST
COMMON OSTEOPOROTIC FRACTURE
types: wedge, biconcave, or crush
many occur with everyday ac vi es (liDing, pushing, pulling)
aDer vertebral fracture, there is a gradual increase in mortality
five-year excess mortality is increased by about 20%
hip fractures - mortality and morbidity - Ans 2nd most common osteoporo c fracture
most caused by fall from standing height
24-30% excess mortality within 1 year
five-year excess mortality is increased by about 20%
,list the economic costs of osteoporosis and compare with other diseases - Ans distribu on of
health care dollars for osteoporosis amount to about 52% for hospitaliza on, 30% for nursing
home care and 13% for outpa ent care
osteopenia (low bone density) and osteoporosis: 44 mil
hypercholesterolemia: 98.6 mil
hypertension: 73.5 mil
diabetes: 23.6 mil
explain the value of bone densitometry for diagnosis, fracture risk es ma on and monitoring -
Ans for diagnosis of osteoporosis, bone densitometry allows diagnosis of osteoporosis in
asymptoma c individuals prior to fracture using the WHO classifica on (-2.5 t score or below)
CAVEATS- some pa ents with -2.5 or below do not have osteoporosis, while some pa ents with
above -2.5 may be diagnosed with osteoporosis ...Low BMD does not equal bone loss
using BMD to predict fracture risk is important because BMD is correlated with bone strength
and BMD is predic ve of future fractures in epidemiologic studies
what cells are responsible for bone modeling and remodeling? - Ans osteoclasts
osteoblasts
osteocytes
define osteoclasts - Ans cells that remove ('c' CHOMP) old bone
define osteoblasts - Ans cells that build ('b' BUILD) new bone
define osteocytes - Ans cells derived from osteoblasts that are mature bone cells thought to
be regulators of remodeling
, what is the bone remodeling cycle - Ans coordinated sequence of ac va on, resorp on, and
forma on
when does bone loss occur? - Ans when resorp on exceeds forma on
when is peak bone mass reached? - Ans it is reached when the growth in the size of bones and
accumula on of bone mineral has stabilized
different skeletal sites reach maturity at different mes: trochanter, mid-teens; femoral neck,
late teens; spine, early 20s.
drama c increase in BMD during adolescence
peak reached in teens or early twen es
overall, age 30
what is the composi on of bone? - Ans bone matrix is 90% collagen and 10% other proteins
cor cal bone makes up the shaDs of long bones and the outer envelope of all bones
(appendicular skeleton) - makes up 80% of the skeleton, 20% of surface area
cancellous or trabecular bone makes up the inner parts of the bones (axial skeleton) - accounts
for 20% of skeleton, but 80% of surface area
describe basic DXA anatomy - Ans central skeleton: vertebral column and proximal femur
(axial skeleton plus hips and shoulders)...spine, ribs, pelvis, shoulders, and hips
peripheral skeleton: upper extremi es and lower extremi es (arms and legs)
describe basic DXA anatomy for the spine - Ans lumbar spine regions of interest (ROI) -
analysis includes L1-L4. the surrounding structures, ribs (T12) and iliac crests, may help with
posi oning
Newest RATED A+ 2025/2026 NEW!!
state the defini on of osteoporosis - Ans NEWEST DEFINITION: "osteoporosis is a skeletal
disorder characterized by compromised bone strength predisposing to an increase risk of
fracture. bone strength reflects the integra on of two main features: bone density and bone
quality"
Osteoporosis can also be defined based on the presence or history of a low-trauma or fragility
fracture
-2.5 T score or below
what is a fragility/low trauma fracture - Ans a fracture resul ng from the force of a fall from a
standing height or less; or a bone that breaks under the condi ons that would not cause a
normal bone to break
summarize the pathophysiology of osteoporosis - Ans bone loss occurs when resorp on
exceeds forma on - this can happen due to a number of things; age related bone loss, disease
related to bone loss (ex: malabsorp on diseases like certain cancers), menopause, lifestyle, etc.
as bone loss occurs, there is loss of quality as well as quan ty. WHO classifies osteoporosis as -
2.5 or below T-score.
what is the defini on of prevalence - Ans frequency of disease at a specific point in me ("30%
of women over age 50 have osteoporosis")
what is the defini on of incidence - Ans new cases of disease over a specific period of me
("the incidence of hip fractures in an elderly popula on is 12 per 1000 person-years")
,explain the prevalence and incidence of osteoporosis and fractures - Ans prevalence of
osteoporosis: es mated 200 million people have osteoporosis worldwide
incidence of osteoporosis: hip fracture projected to increase 240% in women and 320% in men
by 2050
in women, the incidence of clinical vertebral fractures begins to increase around age 55-60 and
rises linearly (5-10 yrs later for men)
in women, the incidence of hip fractures begins to raise about age 65 and increases
exponen ally (5-10 yrs later for men)
distal forearm fractures - mortality and morbidity - Ans third most common osteoporo c
fracture
risk increases early in women (age 45-50) and levels off 60-65
most likely caused by fall on outstretched hand
vertebral fracture - mortality and morbidity - Ans VERTEBRAL FRACTURE IS THE MOST
COMMON OSTEOPOROTIC FRACTURE
types: wedge, biconcave, or crush
many occur with everyday ac vi es (liDing, pushing, pulling)
aDer vertebral fracture, there is a gradual increase in mortality
five-year excess mortality is increased by about 20%
hip fractures - mortality and morbidity - Ans 2nd most common osteoporo c fracture
most caused by fall from standing height
24-30% excess mortality within 1 year
five-year excess mortality is increased by about 20%
,list the economic costs of osteoporosis and compare with other diseases - Ans distribu on of
health care dollars for osteoporosis amount to about 52% for hospitaliza on, 30% for nursing
home care and 13% for outpa ent care
osteopenia (low bone density) and osteoporosis: 44 mil
hypercholesterolemia: 98.6 mil
hypertension: 73.5 mil
diabetes: 23.6 mil
explain the value of bone densitometry for diagnosis, fracture risk es ma on and monitoring -
Ans for diagnosis of osteoporosis, bone densitometry allows diagnosis of osteoporosis in
asymptoma c individuals prior to fracture using the WHO classifica on (-2.5 t score or below)
CAVEATS- some pa ents with -2.5 or below do not have osteoporosis, while some pa ents with
above -2.5 may be diagnosed with osteoporosis ...Low BMD does not equal bone loss
using BMD to predict fracture risk is important because BMD is correlated with bone strength
and BMD is predic ve of future fractures in epidemiologic studies
what cells are responsible for bone modeling and remodeling? - Ans osteoclasts
osteoblasts
osteocytes
define osteoclasts - Ans cells that remove ('c' CHOMP) old bone
define osteoblasts - Ans cells that build ('b' BUILD) new bone
define osteocytes - Ans cells derived from osteoblasts that are mature bone cells thought to
be regulators of remodeling
, what is the bone remodeling cycle - Ans coordinated sequence of ac va on, resorp on, and
forma on
when does bone loss occur? - Ans when resorp on exceeds forma on
when is peak bone mass reached? - Ans it is reached when the growth in the size of bones and
accumula on of bone mineral has stabilized
different skeletal sites reach maturity at different mes: trochanter, mid-teens; femoral neck,
late teens; spine, early 20s.
drama c increase in BMD during adolescence
peak reached in teens or early twen es
overall, age 30
what is the composi on of bone? - Ans bone matrix is 90% collagen and 10% other proteins
cor cal bone makes up the shaDs of long bones and the outer envelope of all bones
(appendicular skeleton) - makes up 80% of the skeleton, 20% of surface area
cancellous or trabecular bone makes up the inner parts of the bones (axial skeleton) - accounts
for 20% of skeleton, but 80% of surface area
describe basic DXA anatomy - Ans central skeleton: vertebral column and proximal femur
(axial skeleton plus hips and shoulders)...spine, ribs, pelvis, shoulders, and hips
peripheral skeleton: upper extremi es and lower extremi es (arms and legs)
describe basic DXA anatomy for the spine - Ans lumbar spine regions of interest (ROI) -
analysis includes L1-L4. the surrounding structures, ribs (T12) and iliac crests, may help with
posi oning
