Chapter 44 - Metabolic Bone Disease (CHERI Notes)

Question 1

_____ is defined as diminished bone QUANTITY in which the bone is otherwise normal. (p.1067)

Answer 1

OSTEOPOROSIS

Question 2

_____ term which the bone quantity is normal but the
QUALITY of the bone is abnormal in that it is not
normally mineralized. (p.1067)

Answer 2

OSTEOMALACIA

• results in excess nonmineralized osteoid

Question 3

It is not possible in most cases to distinguish between
osteoporosis and osteromalacia on plain films; hence
many prefer the term “______” for the plain film finding of diminished mineralization. (p.1067)

Answer 3

OSTEOPENIA

Question 4

There are myriad causes of osteroporosis; the most common of which is ______ ( the so-called _____). (p._____)

Answer 4

PRIMARY OSTEOPOROSIS
(the so-called SENILE OSTEOPOROSIS or OSTEOPOROSIS
OF AGING)

• This is seen most commonly in post-menopausal women and is a major health concern because of the increase of the vertebal body and hip fractures in this patient population.

Question 5

______ implies that an underlying disorder; such as thyrotoxicosis or renal disease; has caused the osteoporosis.
(p.1067)

Answer 5

SECONDARY OSTEOPOROSIS

• only about 5% of the cases of osteoporosis are of the secondary type.
• the differential for presumed osteoporosis would have to include the causes of osteomalacia.

Question 6

The main radiographic finding in osteoporosis is

______ . (p.1067)

Answer 6

THINNING OF THE CORTEX

Question 7

Although OSTEOPOROSIS; can be seen in any bone;

it is most reliably demonstrated in the ____. (p.1067)

Answer 7

SECOND METACARPAL AT THE MID-DIAPHYSIS

Question 8

The normal metacarpal cortical thickening should be

approximately ________. (p.1067)

Answer 8

ONE-FOURTH TO ONE-THIRD THE THICKNESS OF THE
METACARPAL

• In OSTEOPOROSIS; this cortical thickness is decreased
• the metacarpal cortex (and all bony cortices; for that matter) decreases in thickness normally with age and is thinner in females than in males of the same age.

Question 9

TRUE OR FALSE.
Exercise and proper diet seem to help delay the onset
of primary osteoporosis. (p.1067)

Answer 9

TRUE

• calcium additives have not been shown to reverse the
  process of primary osteoporosis.
• Estrogen clearly plays a role in alleviating postmenopausal
  osteoporosis; yet its use in a widespread manner is somewhat
  controversial.

Question 10

A type of osteoporosis that can be seen in a patient

of any age is ______. (p.1067)

Answer 10

DISUSE OSTEROPOROSIS

• it results from immobilization from any cause; most commonly following the treatment of a fracture
• the radiographic appearance of disuse osteoporosis is different from primary osteoporosis is that it occurs somewhat more rapidly and
  gives the bone a patchy apperance.
• this is from osteoclastic resorption in the cortex causing intracortical holes
• if allowed to continue with disuse; the bone would resemble any bone with marked osteoporosis; that is; severe cortical thinning.

Question 11

Occasionally; aggressive osteoporosis from disuse can mimic a permeative lesion such as a _____ or ____ because of the
multiple cortical holes that project over the medullary space; thus resembling a MEDULLARY PERMEATIVE PROCESS. (p.1067)

Answer 11

EWING SARCOMA or MULTIPLE MYELOMA

Question 12

The way to differentiate a true intramedullary permeative process from an intracortical process such as osteoporosis is ____. (p.1067)

Answer 12

TO OBSERVE THE CORTEX AND SEE WHETHER IT IS SOLID OR RIDDLED WITH HOLES

Question 13

If the cortex is solid; one can assume the ____ PROCESS is emanating from the medullary space. (p.1067)

Answer 13

PERMEATIVE process

Question 14

If the cortex has multiple holes; assume the permeative pattern is from the _____ process. (p.1069)

Answer 14

CORTICAL process

Question 15

Two ways a HEMANGIOMA will cause cortical holes. (p.1069)

Answer 15

1. from FOCAL HYPEREMIA causing focal osteoporosis

2. by the BLOOD VESSELS themselves tunneling through the cortex.

Question 16

TRUE OR FALSE?
Radiation can cause cortical holes in bone and mimic a permeative pattern because of the death of cortical osteocytes; which can result in large lacunae in the cortex. (p.1069)

Answer 16

TRUE

• the cortical holes from radiation can be large; in which case they would not be confused with a true permeative process; but they can also be small and resemble an aggressive lesion.

Question 17

Give 6 differential diagnosIs for permeative bone lesions

usually an aggressive process). (p.1069

Answer 17

1. EWING SARCOMA
2. INFECTION
3. EOSINOPHILIC GRANULOMA in a young person (<30 years of age)
4. MULTIPLE MYELOMA
5. METASTATIC CARCINOMATOSIS
6. PRIMARY LYMPHOMA OF BONE IN AN OLDER PATIENT

Question 18

Give 3 differential diagnosis for a pseudopermeative pattern (permeative pattern resulting from cortical holes; less sinister).
(p.1069)

Answer 18

1. AGGRESSIVE OSTEROPOROSIS
2. HEMANGIOMA
3. RADIATION CHANGES

Question 19

___ is the result of too much nonmineralized osteoid. (p.1070)

Answer 19

OSTEOMALACIA

• radiographic findings are almost identical to those of osteroporosis; and for most part; the two disorders are indistinguishable.

Question 20

Most common cause of OSTEOMALACIA? (p.1070)

Answer 20

RENAL OSTEODYSTROPHY

Question 21

The only finding pathognomonic for OSTEROMALACIA is a _____. (p.1070)

Answer 21

LOOSER FRACTURE

• a fracture through the large osteoid seams
• extremely uncommon; but tend to occur in the femur; pelvis and scapula.

Question 22

In children; OSTEOMALACIA is called ____. (p.1070)

Answer 22

RICKETS

• it causes the epiphyses to become flared and irregular and the long bones to undergo bending from the bone softening.
• as in adults; the most common cause is RENAL DISEASE; although other causes such as biliary disease and dietary insufficiencies are occasionally seen.

Question 23

____ occurs from excess parathyroid hormone.(p.1071)

Answer 23

HYPERPARATHYROIDISM

• Parathyroid hormone causes osteoclastic resorption in bone; which leads to osteoporosis and osteomalacia.

Question 24

____ is caused by parathyroid adenomas and hyperplasia.

p. 1071

Answer 24

PRIMARY HYPERPARATHYROIDISM

• up to 40% of patients with primary HPT will demonstrate skeletal abnormalities radiographically.

Question 25

The most common cause of HPT is from ____; which leads to secondary HPT. (p.1071)

Answer 25

RENAL DISEASE

Question 26

______ is the result of the parathyroids secreting excess PTH in response to the hypocalcemia that occurs. (p.1071)

Answer 26

SECONDARY HYPERPARATHYROIDISM

Question 27

The radiographic sign that is pathognomonic for HPT is

____. (p.1071)

Answer 27

SUBPERIOSTEAL BONE RESORPTION

• it is most commonly seen on the RADIAL ASPECT OF THE MIDDLE PHALANGES OF THE HAND; but it can be seen in any long bone in the body.
• it is commonly seen on the medial aspect of the proximal tibia; at the sacroiliac joints and in the distal clavicle.

Question 28

Other radiographic findings of HPT often involves the spine in a manner resembling the stripes on rugby jerseys; hence; the name “______”. (p.1071)

Answer 28

RUGGER JERSEY SPINE

Question 29

______ are cystic lesions that are often expansile and aggressive in appearance. (p.1071)

Answer 29

BROWN TUMORS

Question 30

In place of the metabolic bone survey; it is now recommended that ____ be obtained to look for subperiosteal resorption
(in diagnosing HYPERPARATHYROIDISM). (p.1072)

Answer 30

PLAIN FILMS OF THE HANDS

• a radionuclide bone scan can be obtained in selected cases; which will show increased radionuclide uptake by brown tumors and Looser fractures.
• also; investigation of causes of hypercalcemia; which can be caused by metastatic disease or metabolic bone disease; should include a
  bone scan.

Question 31

____ occurs because of a deficiency of the parathyroid glands to secrete normal amounts of PTH. (p.1072)

Answer 31

HYPOPARATHYROIDISM

-the calvarium on occasion will show thickening; and calcification in the basal ganglia of the brain has been described.

Question 32

_______ is caused by a congenital failure of tissues to respond to PTH. (p.1072)

Answer 32

PSEUDOHYPOPARATHYROIDISM

• parathyroid glands are normal in these cases
• treating these patients with PTH is of no help because the problem lies in the end organs; not the parathyroid glands.
• CHARACTERISTIC APPEARANCE:
  obesity; round facies; short stature and brachydactyly.
• the tubular hands of the hands and feet are often all short.

Question 33

In _____; there is no parathyroid abnormality and no end-organ problem; these patients merely resemble patients with pseudohypoparathyroidism. (p. 1072)

Answer 33

PSEUDOPSEUDOHYPOPARATHYROIDISM

Question 34

MATCHING TYPE:
I. HYPOparathyroidism
II. PSEUDOhypoparathyroidism
III. PSEUDOPSEUDOhypoparathyroidism

A. Parathyroid gland problem
B. End-organ problem
C. Mimicker of pseudohypoparathyroidism morphologically (p.1072)

Answer 34

I. - A.
II. - B.
III. - C.

Question 35

A secreting adenoma or hyperplasia of the anterior lobe of the pituitary gland will result in accelerated bone growth.
A. If it occurs BEFORE the epiphyses close;
it causes ____.
B. If it occurs AFTER the epiphyses are closed;
the result is ___. (p.1072)

Answer 35

A. GIANTISM

B. ACROMEGALY

Question 36

Thickening if the heel pad adjacent to the calcaneus has been used as a sign of _____. (p. 1072)

Answer 36

ACROMEGALY

• skull film invariably shows calvarial thickening;enlarged sinuses; and an enlarged sella turcica
• jaw is prognathic
• the terminal tufts of the distal phalanges become hypertrophied and have a so-called SPADE APPEARANCE (an appearance not unlike a spade or shovel)
• the joint spaces are occasionally minimally enlarged because of hypertrophy of the hyaline articular cartilage
• early degenerative joint disease ensues because the cartilage itself is abnormal

Question 37

A rare manifestation of hyperthyroidism in adults is ______. (p.1073)

• a characteristic appearing periostitis occurs in the metacarpals and phalanges of the hands and feet.

Answer 37

THYROID ACROPACHY

• this occurs only after prior thyroidectomy and the cause is unknown.
• In children; hyperthyroidism can result in increased skeletal maturation; however this is seldom marked.

Question 38

A useful differential point that can be used to tell thyroid acropachy from other causes of diffuse periostitis. (p.1073)

Answer 38

INVOLVEMENT OF THE ULNAR ASPECT OF THE 5TH METACARPAL

Question 39

Decreased thyroid secretion or ____; results in delayed skeletal maturation in children. (p. 1073)

Answer 39

CRETINISM

• delay in ossification of epiphyseal centers with occasional appearance of “stippled” epiphyses is seen
• a delay in epiphyseal closure also occurs; in some instances with failure of epiphyseal closure noted in the third and fourth decade.

Question 40

The radiographic finding of DIFFUSE INCREASED BONE DENSITY; _____ is somewhat uncommon.(p.1073)

Answer 40

OSTEOSCLEROSIS

Question 41

Mnemonic AID for DIFFUSE OSTEOSCLEROSIS
differentials: (p.1073)
“Regular Sex Makes Occasional Perversions Much
More Pleasurable And Fantastic”

Identify them. (10)

Answer 41

1. Renal osteodystrophy
2. Sickle cell disease
3. Myelofibrosis
4. Osteopetrosis
5. Pyknodysostosis
6. Metastatic carcinoma
7. Mastocytosis
8. Paget disease
9. Athletes
10. Fluorosis

Question 42

____ is by far the most common disease in which osteosclerosis is seen. (p. 1073-1074)

Answer 42

RENAL DISEASE

Question 43

Most common presentation of RENAL OSTEODYSTROPHY is ___. (p.1074)

Answer 43

OSTEOPENIA

• about 10% to 20% of the patients with renal osteodystrophy will exhibit osteosclerosis

Question 44

the sine quanon of renal osteodystrophy is ______.; seen earliest and most reliably at the radial aspect of the middle phalanges of the hands. (p. 1074)

Answer 44

SUBPERIOSTEAL BONE RESORPTION

Question 45

Aside from dense bones; what other two additional signs are due to SICKLE CELL DISEASE in the bone? (p.1074)

Answer 45

1. Bone infarcts
2. Step-off deformities of the vertebral body endplates
   - these are also called “FISH” vertebrae after their appearance like the vertebrae found in fish.

• avascular necrosis of the hip is frequently an accompanying finding.

Question 46

Also called AGNOGENIC MYELOID METAPLASIA; ____ is a disease caused by progressive fibrosis of the marrow in patients older than 50 years of age. (p. 1074)

Answer 46

MYELOFIBROSIS

• leads to anemia with marked splenomegaly and extramedullary hematopoiesis

Question 47

Whenever osteosclerosis is seen in the a patient older thatn 50 years of age; a search should be made for a ____ and ____. (p. 1074)

Answer 47

LARGE SPLEEN and EXTRAMEDULLARY HEMATOPOIESIS

Question 48

A hereditary abnormality that results in extremely dense bones throughout the skeleton. (p. 1074)

Answer 48

OSTEOPETROSIS

• CONGENITA FORM
• occurs at birth and can be lethal
• TARDA FORM
• is seen in older children and adults has milder clinical problems.

Question 49

A characteristic finding in OSTEOPETROSIS often seen in the vertebral bodies in which the vertebae have a small replica of the vertebral body inside the normal one. (p. 1075)

Answer 49

BONE-IN-BONE APPEARANCE

Question 50

Also a characteristic finding in OSTEOPETROSIS in which the endplates are densely sclerotic; giving the appearance of a sandwich. (p.1075)

Answer 50

SANDWICH VERTEBRAE

• resembles a rugger jersey spine but can be differentiated by being much denser and more sharply defined

Question 51

The distinguishing radiographic finding that is essentially pathognomonic for PYKNODYSOSTOSIS is ______. (p.1075)

Answer 51

ACROOSTEOLYSIS WITH SCLEROSIS

*** The distal phalanges often have the appearance of chalk that has been put into a pencil sharpener: they are pointed and dense.

Question 52

Another name for PYKNODYSOSTOSIS? (p.1075)

Answer 52

TOULOUSE-LAUTREC SYNDROME

• named from the famous artist who was afflicted with pyknodysostosis

Question 53

_____ is a characteristis skin lesion found in patients with mastocytosis. (p. 1076)

Answer 53

URTICARIA PIGMENTOSA

Question 54

Paget disease classically causes bony enlargement; which most commonly occurs in the ___. (p.1077)

Answer 54

PELVIS

• the iliopectineal line on the pelvic brim must be thickened if Paget disease is present.
• it can occur in any bone in the body; including the smaller bones of the hands and feet.

Question 55

Enumerate the 3 distinct phases of Paget Disease (p.1077)

Answer 55

1. Lytic phase
2. Sclerotic phase
3. Mixed lytic-sclerotic phase

Question 56

Phase of Paget disease which often has a sharp leading edge called a flame-shaped or blade-of-grass leading edge. (p.1077)

Answer 56

LYTIC PHASE

Question 57

In a long bone; with the sole exception being the tibia; Paget Disease always starts at the ____. (p.1077)

Answer 57

END OF THE BONE

• therefore if a lesion is present in the middle of a long bone and does not extend to either end; one can safely exclude Paget Disease

Question 58

TRUE OR FALSE?
Plain film radiographs of professional athletes quite often demonstrate increased cortical thickness and apparent diffuse osteosclerosis to the point of appearing pathologic. (p.1077)

Answer 58

TRUE

• increased stress causes hypertrophy of bone as well as muscle.