Pathophysiology: Chapter 45: Alterations of Musculoskeletal Function

Question 1

What type of fracture occurs at a site of a preexisting bone abnormality and is a result of a
force that would not normally cause a fracture?
a. Idiopathic c. Pathologic
b. Incomplete d. Greenstick

Answer 1

ANS: C
Only a pathologic fracture is a break at the site of a preexisting abnormality, usually by
force that would not fracture a normal bone.

Question 2

Which type of fracture usually occurs in an individual who engages in a new activity that
is strenuous and repetitive?
a. Stress c. Insufficiency
b. Greenstick d. Pathologic

Answer 2

ANS: A
Only a stress fracture occurs in normal or abnormal bone that is subjected to repeated
stress, such as repetitive and strenuous activities that occur during athletics.

Question 3

Which term is used to identify the temporary displacement of two bones causing the bone
surfaces to partially lose contact?
a. Dislocation c. Malunion
b. Subluxation d. Nonunion

Answer 3

ANS: B
Dislocation is the temporary displacement of a bone from its normal position in a joint. If
the contact between the two surfaces is only partially lost, then the injury is referred to as a
subluxation. This selection is the only option that identifies the temporary displacement of
two bones, causing the bone surfaces to partially lose contact.

Question 4

Improper reduction or immobilization of a fractured femur can result in which outcome
after cast removal?
a. The muscles around the fracture site are weak.
b. The fracture requires 6 to 8 weeks of physical therapy.
c. The skin under the cast is dry and flaky.
d. The bone is not straight.

Answer 4

ANS: D
Improper reduction or immobilization of a fractured bone may result in nonunion, delayed
union, or malunion. Malunion is the healing of a bone in a nonanatomic position that could
result in the bone not being straight. The other options are not outcomes of improper
reduction or immobilization.

Question 5

Which structure attaches skeletal muscle to bone?

a. Tendon c. Bursa
b. Ligament d. Mesentery

Answer 5

ANS: A
A tendon is fibrous connective tissue that attaches skeletal muscle to bone. None of the
other options are associated with this function.

Question 6

The tear in a ligament is referred to as a:

a. Fracture c. Disunion
b. Strain d. Sprain

Answer 6

ANS: D
Ligament tears are commonly known as sprains. None of the other options are associated
with this damage.

Question 7

Which medical diagnosis is characterized by tissue degeneration or irritation of the
extensor carpi radialis brevis tendon?
a. Lateral epicondylitis c. Bursitis
b. Medial tendinitis d. Lateral tendinitis

Answer 7

ANS: A
Only lateral epicondylopathy, commonly called tennis elbow, is the result of tissue
degeneration or irritation of the extensor carpi radialis brevis tendon at its origin.

Question 8

The pain resulting from tendon and ligament injuries is usually described as:

a. Dull and diffuse, persisting over the distribution of the tendon or ligament
b. Sharp and localized, persisting over the distribution of the tendon or ligament
c. Pins-and-needle sensations that occur distal to the injury with movement
d. Intermittent and aching, occurring over the distribution of the tendon or ligament

Answer 8

ANS: B
The pain resulting from tendon and ligament injuries is usually described as being sharp
and localized, persisting over the distribution of the tendon or ligament. This selection is
the only option that accurately describes this type of pain.

Question 9

How is rhabdomyolysis characterized?

a. Paralysis of skeletal muscles, resulting from an impaired nerve supply
b. Smooth muscle degeneration, resulting from ischemia
c. Lysis of skeletal muscle cells through the initiation of the complement cascade
d. Release of myoglobin from damaged striated muscle cells

Answer 9

ANS: D
Rhabdomyolysis involves the release of myoglobin when muscle cells are damaged. This
selection is the only accurate description of rhabdomyolysis.

Question 10

Which pathophysiologic alteration precedes crush syndrome after prolonged muscle
compression?
a. Muscle ischemia c. Volkmann contracture
b. Myoglobinuria d. Neural injury

Answer 10

ANS: B
Myoglobinuria is an excess of myoglobin (an intracellular muscle protein) in the urine.
Muscle cell damage releases the myoglobin. The most severe form is often called crush
syndrome. Less severe and more localized forms of muscle damage are called
compartment syndromes. This selection is the only option that accurately identifies the
pathophysiologic alteration that precedes crush syndrome.

Question 11

By the time osteoporosis is visible on an x-ray examination, up to what percent of bone
has been lost?
a. 30% c. 50%
b. 40% d. 60%

Answer 11

ANS: A
Generally, osteoporosis is radiographically detected as increased radiolucency of bone. By
the time abnormalities are detected by x-ray examination, as much as 25% to 30% of bone
tissue may have been lost.

Question 12

A bone density of 645 mg/cm2 would support which diagnosis?

a. Osteoplasia c. Osteopenia
b. Osteoporosis d. Osteomalacia

Answer 12

ANS: B
The World Health Organization (WHO) has defined osteoporosis on the basis of bone
density. Normal bone is greater than 833 mg/cm2; osteopenia, or decreased bone mass, is
833 to 648 mg/cm2; osteoporosis is less than 648 mg/cm2. This selection is the only
accepted option.

Question 13

Which type of osteoporosis would a person develop after having the left leg in a cast for 8
weeks to treat a compound displaced fracture of the tibia and fibula?
a. Iatrogenic c. Idiopathic
b. Regional d. Osteoblastic

Answer 13

ANS: B
Of the options available, only classic regional osteoporosis is associated with disuse or
immobilization of a limb because of fractures, motor paralysis, or bone or joint
inflammation.

Question 14

Considering the pathophysiologic process of osteoporosis, after being activated by
receptor activator of nuclear factor B ligand (RANKL), receptor activator of nuclear
factor B (RANK) activates which of the following?
a. Osteoclast apoptosis
b. Osteoblast survival
c. Osteoprotegerin
d. Osteoclast survival

Answer 14

ANS: D
RANKL activates the receptor RANK, which is expressed on osteoclasts and their
precursors and suppresses apoptosis, which leads to activation and the prolongation of
osteoclast survival. This statement is not true of any of the other options.

Question 15

Considering the pathophysiologic process of postmenopausal osteoporosis, which changes
are believed to play a significant role in the development of age-related bone loss?
a. Increased oxidative stress and increased intracellular reactive oxygen species
b. Hypoparathyroidism
c. Increased body weight
d. Decreased formation and short life span of osteoclasts

Answer 15

ANS: A
Postmenopausal osteoporosis occurs in middle-aged and older women. It can occur
because of estrogen deficiency, as well as estrogen-independent, age-related mechanisms
(e.g., secondary causes such as hyperparathyroidism and decreased mechanical
stimulation). Recent studies indicate that increased oxidative stress (OS) and increased
intracellular reactive oxygen species (ROS) play significant roles in the development of
age-related bone loss, as well as other age-related changes in the body. Hormonal
deficiency also can increase with stress, excessive exercise, and low body weight.
Increased formation and longevity of osteoclasts results in increased bone resorption and is
associated with a cascade of proinflammatory cytokines.

Question 16

Considering the pathophysiologic process of osteoporosis, which hormone exerts
antiapoptotic effects on osteoblasts but proapoptotic effects on osteoclasts?
a. Parathyroid hormone c. Growth hormone
b. Glucocorticoid d. Estrogen

Answer 16

ANS: D
Data reveal that sex steroids (e.g., estrogens) exert antiapoptotic effects on osteoblasts but
exert proapoptotic effects on osteoclasts; in both scenarios, activating the extracellular
signal-regulated kinases (ERKs) accomplish these effects. This process is not true of any
of the other options.

Question 17

Considering the pathophysiologic process of osteoporosis, what are the effects of
extracellular signal-regulated kinases (ERKs) and receptor activator of nuclear factor B
ligand (RANKL) on osteoblasts and osteoclasts?
a. ERKs increase the life span of osteoclasts, and RANKL decreases the life span of
osteoblasts.
b. ERKs and RANKL increase the life span of osteoclasts and decrease the life span
of osteoblasts.
c. ERKs and RANKL increase the life span of osteoblasts and decrease the life span
of osteoclasts.
d. ERKs increase the life span of osteoblasts, and RANKL decreases the life span of
osteoclasts.

Answer 17

ANS: B
In addition to ERKs, RANKL is required for the antiapoptotic effect and thus longer life
span of osteoclasts. This effect also shortens the life span of the bone-forming cells, or
osteoblasts. This process is not true of any of the other options.

Question 18

What is the most common clinical manifestation of osteoporosis?

a. Bone deformity c. Pathologic fracture
b. Bone pain d. Muscle strain

Answer 18

ANS: A

The most common clinical manifestation of osteoporosis is bone deformity.

Question 19

Which disorder is characterized by the formation of abnormal new bone at an accelerated
rate beginning with excessive resorption of spongy bone?
a. Osteomalacia c. Osteoporosis
b. Paget disease d. Osteosarcoma

Answer 19

ANS: B
Of the available options, only Paget disease (osteitis deformans) is a state of increased
metabolic activity in bone characterized by abnormal and excessive bone remodeling, both
resorption and formation. Chronic accelerated remodeling eventually enlarges and softens
the affected bones.

Question 20

Which statement is false about factors that contribute to the difficulty in treating bone
infections?
a. Bone contains multiple microscopic channels that are impermeable to the cells and
biochemicals of the body’s natural defenses.
b. Microcirculation of bone is highly vulnerable to damage and destruction by
bacterial toxins, leading to ischemic necrosis of bone.
c. Bone cells have a limited capacity to replace bone destroyed by infections.
d. Bacteria are walled off by macrophages and T lymphocytes; consequently, the
antibiotics cannot penetrate the infected area.

Answer 20

ANS: D
Bacteria are not walled off by macrophages and T lymphocytes, thus inhibiting the effects
of antibiotics. The other options are true statements regarding factors that contribute to the
difficulty in treating bone infections.

Question 21

Bone death as a result of osteomyelitis is due to what?

a. Formation of immune complexes at the site of infection
b. Localized ischemia
c. Tumor necrosis factor–alpha (TNF-) and interleukin 1 (IL-1)
d. Impaired nerve innervation at the site of infection

Answer 21

ANS: B
Vessel damage causes local thrombosis (blockage) of the small vessels, which leads to
ischemic necrosis (death) of bone. This selection is the only option that is associated with
bone death as a result of osteomyelitis.

Question 22

When considering osteomyelitis, sequestrum is identified as what?

a. An area of devascularized and devitalized bone
b. An enzyme that phagocytizes necrotic bone
c. A subperiosteal abscess
d. A layer of new bone surrounding the infected bone

Answer 22

ANS: A
Lifting of the periosteum disrupts blood vessels that enter bone through the periosteum,
which deprives the underlying bone of its blood supply. This deprivation leads to necrosis
and death of the area of infected bone, producing sequestrum, an area of devitalized bone.
None of the other available options accurately identify the term sequestrum.

Question 23

What pattern of bone destruction is described as not well-defined and not easily separated
from normal bone?
a. Moth-eaten c. Geographic
b. Permeative d. Porous

Answer 23

ANS: A
Moth-eaten pattern is the only option that involves destruction that is not well-defined and
not easily separated from normal bone.

Question 24

Which statement accurately describes a characteristic of osteosarcoma?
a. Slow-growing tumor that begins in the bone marrow and infiltrates the trabeculae
b. Solitary tumor that most often affects the metaphyseal region of the femur or tibia
c. Aggressive tumor most often found in the bone marrow of long bones
d. Tumor that infiltrates the trabeculae in spongy bone and implants in surrounding
tissue by seeding

Answer 24

ANS: C
An osteosarcoma is a malignant bone-forming tumor. It is aggressive and most often found
in bone marrow; it has a moth-eaten pattern of bone destruction. This selection is the only
option that accurately describes a characteristic of osteosarcoma.

Question 25

Which statement is false concerning giant cell tumors?
a. Giant cell tumors are an overexpression of genes including osteoprotegerin ligand
(OPGL).
b. The tumors are malignant, solitary, and irregularly shaped.
c. Giant cell tumors are typically located in the epiphysis in the femur, tibia, radius,
and humerus.
d. They are slow-growing tumors that extend over the articular cartilage.

Answer 25

ANS: B
The giant cell tumor is generally a benign, solitary, circumscribed tumor that causes
extensive bone resorption because of its osteoclastic origin. The other options are true
statements concerning giant cell tumors.

Question 26

Which is a characteristic of inflammatory joint disease?

a. Unilateral joint involvement
b. Normal joint synovial fluid
c. Absence of synovial membrane inflammation
d. Systemic symptoms of inflammation

Answer 26

ANS: D
Inflammatory joint disease is characterized by systemic signs of inflammation (fever,
leukocytosis, malaise, anorexia, hyperfibrinogenemia) and inflammatory damage or
destruction in the synovial membrane or articular cartilage. This selection is the only
option that accurately describes a characteristic of inflammatory joint disease.

Question 27

hat is a primary defect in osteoarthritis?

a. Stromelysin and acid metalloproteinase break down articular cartilage.
b. Immunoglobulin G (IgG) destroys the synovial membrane.
c. Synovial membranes become inflamed.
d. Cartilage-coated osteophytes create bone spurs.

Answer 27

ANS: A
Of the options available, the primary defect in osteoarthritis is the loss of articular
cartilage.

Question 28

In osteoarthritis, what is the effect of the disruption of the pumping action of
proteoglycans?
a. Pump malfunction stimulates the induction of nitric oxide synthase and nitric
oxide, which degrades the cartilage.
b. Cartilage is damaged by proteolytic enzymes because they cannot be pumped out
of the joint.
c. Cartilage becomes dry, brittle, and wears away because fluid cannot be pumped
into the cartilage.
d. Cartilage takes in too much fluid and is unable to withstand the stresses of weight
bearing.

Answer 28

ANS: D
Changes in the conformation of proteoglycans disrupt the pumping action that regulates
the movement of water and synovial fluid into and out of the cartilage. Without the
regulatory action of the proteoglycan pump, cartilage imbibes too much fluid and becomes
less able to withstand the stresses of weight bearing. This selection is the only option that
accurately describes the disruption of the pumping action of proteoglycans when
considering osteoarthritis.

Question 29

Which joint disease is characterized by joint stiffness on movement and joint pain of
weight-bearing joints that is usually relieved by rest?
a. Gouty arthritis
b. Rheumatoid arthritis
c. Osteoarthritis
d. Suppurative arthritis

Answer 29

ANS: C
Pain and stiffness in one or more joints, usually weight-bearing or load-bearing joints, are
the first symptoms of osteoarthritis. Use-related joint pain relieved by rest is a key feature.
This selection is the only option that accurately identifies the disease associated with the
described symptoms.

Question 30

Which medical diagnosis is described as a chronic inflammatory joint disease
characterized by stiffening and fusion of the spine and sacroiliac joints?
a. Ankylosing spondylitis
b. Rheumatoid arthritis
c. Paget disease
d. Fibromyalgia

Answer 30

ANS: A
Of the options available, only ankylosing spondylitis (spondyloarthritis) is described as a
chronic, inflammatory joint disease characterized by stiffening and fusion (ankylosis) of
the spine and sacroiliac joints.

Question 31

What is the primary pathologic alteration resulting from ankylosing spondylitis (AS)?

a. Inflammation of the sacroiliac joint
b. Inflammation of the long bones
c. Inflammation of fibrocartilaginous joints of the vertebrae
d. Inflammation of the small hand and feet bones

Answer 31

ANS: C
AS involves inflammation of fibrocartilage in cartilaginous joints, primarily in the
vertebrae. The other options do not accurately describe the primary pathologic alterations
of AS.

Question 32

In ankylosing spondylitis, the CD8+ T cells are presented with which antigen?

a. Synovium c. Tendons
b. Cartilage d. Ligaments

Answer 32

ANS: B
Cartilage antigens are proposed as the targets for the immune response and the
presentation of such antigens to CD8+ T cells. This statement is not true of any of the
other options.

Question 33

People with gout are at high risk for which co-morbid condition?

a. Renal calculi c. Anemia
b. Joint trauma d. Hearing loss

Answer 33

ANS: A
Renal stones are 1000 times more prevalent in individuals with primary gout than they are
in the general population. This statement is not true of any of the other options.

Question 34

What causes the crystallization within the synovial fluid of the joint affected by gouty
arthritis?
a. Reduced excretion of purines
b. Overproduction of uric acid
c. Increase in the glycosaminoglycan levels
d. Overproduction of proteoglycans

Answer 34

ANS: B
When the uric acid reaches a certain concentration in fluids, it crystallizes, forming
insoluble precipitates that are deposited in connective tissues throughout the body.
Crystallization in synovial fluid causes acute, painful inflammation of the joint, a
condition known as gouty arthritis. This selection is the only option that accurately
identifies the cause of crystallization in synovial fluid associated with gouty arthritis.

Question 35

The pathophysiologic presentation of gout is closely linked to the metabolism of which
chemical?
a. Purine c. Vitamin E
b. Pyrimidine d. Amino acid

Answer 35

ANS: A
The pathophysiologic presentation of gout is closely linked only to purine metabolism (or
cellular metabolism of purines) and kidney function.

Question 36

Which clinical manifestations are associated with fibromyalgia?

a. Hot, tender, and edematous muscle groups bilaterally
b. Fasciculations of the upper and lower extremity muscles
c. Exercise intolerance and painful muscle cramps
d. Sensitivity at tender points and profound fatigue

Answer 36

ANS: D
Widespread joint and muscle pain, fatigue, and tender points are characteristics of
fibromyalgia, a chronic musculoskeletal syndrome. Increased sensitivity to touch (i.e.,
tender points), the absence of systemic or localized inflammation, and fatigue and sleep
disturbances are common. Fatigue is profound. The remaining options include symptoms
not generally associated with fibromyalgia.

Question 37

At what age is peak bone mass and strength reached in women?
a. 15 years c. 30 years
b. 20 years d. 35 years
.

Answer 37

ANS: C
Bone formation continues at a pace faster than resorption until peak bone mass—or
maximum bone density and strength—is reached at approximately 30 years of age, after
which bone resorption slowly exceeds bone formation

Question 38

What event is associated with the beginning of bone loss in women?

a. Puberty c. Childbirth
b. Sexual activity d. Menopause

Answer 38

ANS: D
Bone loss in women is associated with menopause. Bone loss is most rapid in the first
years after menopause but persists throughout the postmenopausal years. The other options
are not relevant as triggers for bone loss.

Question 39

What term is used to identify the calcium crystals that are associated with chronic gout?

a. Stones c. Tophi
b. Spurs d. Nodes

Answer 39

ANS: C
With time, crystal deposition in subcutaneous tissues causes the formation of small white
nodules, or tophi, that are visible through the skin. Crystal aggregates deposited in the
kidneys can form urate renal stones and lead to renal failure. None of the other options are
associated with the calcium crystals resulting from chronic gout.