Term
The bones of the skeleton are differentiated in four ways. Which of the four is unique to densitometry?
a) Weight bearing or non weight bearing
b) Axial or appendicular
c) Central or peripheral
d) Cortical or trabecular |
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Definition
c) Central or peripheral
Differentiating central from peripheral skeletal sites is unique to densitometry because central DXA units scan different sites than peripheral scanners. Central DXAs can scan the spine and proximal femur, giving better insight to the health of a patient's bones. |
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Term
Why is it important to understand which sites are predominantly trabecular or predominantly cortical in densitometry?
a) Trabecular bone has a greater metabolic rate.
b) Some diseases have a preference for one type of bone over another.
c) Certain therapies will produce better results in sites that are predominantly trabecular.
d) All the above. |
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Definition
d) All the above.
Trabecular bone has a greater metabolic rate and is often the target for bone diseases. Cortical bone is the hard, exterior bone. |
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Term
True or False
Osteoblasts are bone absorbing cells. |
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Definition
False
Osteoblasts are bone forming cells. Osteoclasts are bone absorbing cells. |
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Term
What does the Z-Score represent?
a) A comparison of the BMD of a specific person to the average value of same age adults.
b) A comparison of the BMD of a specific person to the average peak value of young adults.
c) Only used on patients over the age of 80.
d) None of the above. |
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Definition
a) A comparison of the BMD of a specific person to the average value of same age adults.
The Z-Score compares the BMD of a specific person to the average value of same age adults. |
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Term
True or False
The femoral neck is predominantly cortical bone. |
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Definition
True
This statement is true. The femoral neck is predominantly cortical bone. Cortical bone is the hard, exterior bone. |
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Term
Densitometry was first described a century ago in _________ radiography.
a) Dental
b) Emergency
c) Skeletal
d) Animal Husbandry |
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Definition
a) Dental
Even though clinical densitometry is a relatively new practice, dental radiography utilized the concept of densitometry. |
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Term
What are the fundamental roles bones play in the human body?
a) Protection for the brain, marrow and sensitive internal organs
b) Structural support and attachment sites for muscles
c) Metabolic organ with reserves of calcium and phosphates
d) All the above |
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Definition
d) All the above
Bone gives the body structure and a landing site for muscles, provide protection for brain and internal organs. It is also a metabolic organ. |
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Term
What is peak bone density?
a) The highest BMD measurement on a given scan of PA spine
b) The T-Score of the baseline DXA of any site
c) The maximum bone mass that is achieved for any given skeletal site, usually reached in healthy adults by age 35.
d) The BMD a person is born with. |
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Definition
c) The maximum bone mass that is achieved for any given skeletal site, usually reached in healthy adults by age 35.
Peak bone density is the maximum bone mass that is achieved for any given skeletal site. This premise is also the basis for demographic population used for the young adult age match reference data base. |
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Term
True or False
Denistometry is principally a quantitative measurement technique. |
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Definition
True
In this scope, the quantity being measured is bone mass or density. This concept is present in many areas of clinical medicine, such as blood glucose and sphygmomanometry. |
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Term
The T-Score is a standard score. Why is this significant?
a) There is no significance. It is just a simplified method of expressing risk.
b) Standard scores are expressed as standard deviations.
c) Standard scores signify how many standard deviations, above or below the mean, a specific value lies.
d) All the above
e) B and C only |
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Definition
e) B and C only
T-Scores and Z-Scores are expressed as standard scores and signify how many standard deviations a specific value (a patient's BMD) lies from the mean (reference database) |
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Term
What is the synchronized order of the bone remodeling cycle?
a) Activation, resorption and formation
b) Formation, activation and resorption
c) Activation, destruction, reconstruction
d) Resorption, restoration, activation |
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Definition
a) Activation, resorption and formation
The synchronized cycle of bone remodeling is activation, resorption and formation. |
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Term
What are two major types of bones?
a) Short and long
b) Skeletal and peripheral
c) Cartilage and connective
d) Cortical and trabecular |
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Definition
d) Cortical and trabecular
Cortical and trabecular are the two types of bone. Cortical is the hard outer shell and trabecular is the spongy inner bone. |
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Term
Name the bone cells.
a) Osteoclasts, marrow, lining cells, lipocyte
b) Osteoblasts, Osteocytes, marrow, neurons
c) Osteoclasts, Osteoblasts, Osteocytes, lining cells
d) Neurons, lipocytes, marrow, lining cells |
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Definition
c) Osteoclasts, Osteoblasts, Osteocytes, lining cells
Osteoclasts, osteoblasts,osteocytes, and lining cells are the four bone cells responsible for forming and maintaining bone. |
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Term
______________ bone provides most of the metabolic function and is the primary site for bone remodeling.
a) Calcium
b) Trabecular
c) Cortical
d) Lamellar |
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Definition
b) Trabecular
Trabecular bone provides most of the metabolic function. Cortical bone provides protection and mechanical function. |
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Term
Limb girdles, including pelvis and scapulae, and extremities are considered the ____________ skeleton.
a) Axial
b) Appendicular
c) Primary
d) Superficial |
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Definition
b) Appendicular
The limb girdles and extremities are part of the appendicular skeleton. |
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Term
True or False
Hip Fractures are the most common fracture site for osteoporosis related fractures. |
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Definition
False
This statement is false. Vertebral fractures are the most common fracture site. |
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Term
Using the four skeletal classes, describe the lumbar spine.
a) Peripheral, axial, non-weigh bearing , cortical
b) Axial, central, weigh bearing, cortical
c) Appendicular, peripheral, weight bearing, predominantly trabecular
d) Central, weight bearing, axial, predominantly trabecular |
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Definition
d) Central, weight bearing, axial, predominantly trabecular
According to the four classes, the spine falls in the central, weight bearing, axial locations and is comprised of predominantly trabecular bone. |
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Term
Bone is a living biomaterial and can:
a) Adapt to meet functional demands
b) Repair itself
c) Neither of the above
d) A and B only |
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Definition
d) A and B only
Bone is a living biomaterial that adapts to meet functional needs and can repair itself. |
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Term
FRAX is an absolute fracture risk prediction tool that uses clinical risk factors to predict the absolute 10-year risk of fracture. Which of the following statements is true?
a) FRAX can be used to predict hip fracture or a major osteoporosis fracture at any site.
b) FRAX can function as a stand alone site but is incorporated into DXA software.
c) FRAX can be used with femoral neck BMD or T-Score.
d) All the above. |
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Definition
d) All the above.
FRAX can predict fracture as a stand alone website but is built into the software of most DXAs. It can only be used with the BMD or T-Score of the femoral neck. |
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Term
T-Score (% young adult) compares the patient's BMD to what?
a) The average value of same age adults
b) The calculated value of the patient's peak bone density.
c) The average peak value of young adults.
d) The database of the manufacturer's choosing. |
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Definition
c) The average peak value of young adults.
The T-Score compares the BMD of a specific patient to a database made up of young healthy adults. |
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