Radiology of Metabolic Bone Disease

Question 1

describe the composition of bone.

Answer 1

water- 8%
organic substance- 21%
inorganic substance- 71%

Question 2

describe the conditions that aid osteoblastic activity in osteogenesis.

Answer 2

local alkaline environment- thanks to alkaline phosphatase

*osteogenesis is also stimulated by a low O2 tension and acidic environment

Question 3

describe the conditions that promote osteolysis.

Answer 3

• high O2 tension
• acidic environment
• decreased Ca2+ and phosphate ions

Question 4

what is the descriptive term for a loss of bone density observed radiographically?

Answer 4

osteopenia

Question 5

what % of bone loss is clinically significant?

Answer 5

50% bone less

Question 6

what % of bone loss is radiographically detectable?

Answer 6

30%

Question 7

what effect does a vitamin C deficiency have on bone density?

Answer 7

scurvy –> osteoporosis

• osteoblasts fail to produce osteoid so there is a lack of mineralization
• seen in alcoholics/starving ppl

Question 8

what are the 3 stages of CRPS?

Answer 8

Stage 1: Acute
Stage 2: Dystrophic
Stage 3: ATrophic

Question 9

describe the radiographic findings for CRPS.

Answer 9

(Sudeck’s atrophy:)

• patchy osteoporosis
• accentuated joints
• subchondral bone resorption
• ground glass appearance

Question 10

Vit D deficiency can lead to what disease?

Answer 10

osteomalacia/rickets –> skeletal deformity

Question 11

Looser’s lines is seen in what disease?

Answer 11

osteomalacia

Question 12

Milkman’s fracture is seen in what disease?

Answer 12

Rickets

Question 13

Give some radiographic features of endocrinopathies.

Answer 13

• brown tumors

- soft tissue calcifications

Question 14

expansile areas of lytic distruction indicate what?

Answer 14

marrow packing disorders

Question 15

is Paget’s disease an osteoporosis or osteosclerosis disease?

Answer 15

osteosclerotic

Question 16

describe the 3 phases of Paget’s disease.

Answer 16

1. lytic phase
2. sclerotic phase
3. combined phase
   - ->malignant transformation

Question 17

what is osteopetrosis?

Answer 17

incidental or pathologic fracture

–> failure to absorb primary spongiosa

Question 18

explain the radiographic findings of osteopetrosis.

Answer 18

-bone within bone appearance

Question 19

what is the appearance of osteopoikilosis?

Answer 19

• multiple bone islands appearance

- multiple round/ovoid bone densities

Question 20

what is the disease called that is ectopic calcification in the soft tissue?

Answer 20

myositis ossificans