10A. Radiographs - Bone Tumors

Question 1

Answer 1

aneurysmal bone cyst

Question 2

osteoma

Answer 2

• benign, slow-growing, and usually asymptomatic
• MC in skull, or in tubular bones of extremities
• Multiple is assoc w/ Gardner sydrome

Question 3

Osteoid Osteoma

Answer 3

Benign bone-forming tumor

10-20s y/o

“pain worse at night, relieved by aspirin or NSAIDs”

oval/round radiolucent area <2 cm in diameter

in talus, or calcaneus (MC), or in long diaphyseal bones

Question 4

Enostosis

Answer 4

“Bone Island”

Question 5

osteoblastoma

Answer 5

“Giant Osteoid Osteoma, Osteogenic Fibroma”

well-circumscribed, expansile, osteolytic lesion >1 cm w/ areas of calcifications

Question 6

osteoblastoma

Answer 6

fibula;

• lesions are predominantly lytic, with a rim of reactive sclerosis
• may have “bubbly appearance”

Question 7

ossifying fibroma

Answer 7

Question 8

osteosarcoma

Answer 8

osteogenic sarcoma

Malignant bone forming tumor

Question 9

osteosarcoma

Answer 9

assoc. w/ paget disease of the bone

periosteal reaction - sunburst, codman triangle, onion skin rxn is less commonly seen

Question 10

osteosarcoma

Answer 10

Question 11

enchondroma

Answer 11

2nd proximal phalanx

Question 12

enchondroma

Answer 12

Question 13

other name for Enchondromatosis

Answer 13

Ollier Disease

Question 14

Maffucci Syndrome

Answer 14

• Multiple enchondromas associated with soft tissue hemangiomas
• Occurs in the first decade of life
• 30% of cases become malignant.
• Most commonly seen in the hands

Question 15

chondroblastoma

Answer 15

Question 16

chondroblastoma

Answer 16

Question 17

giant cell tumor

Answer 17

Question 18

Answer 18

unicameral bone cyst

Question 19

Answer 19

unicameral bone cyst

Question 20

Answer 20

Aneurysmal bone cyst

Question 21

Answer 21

Aneurysmal bone cyst

Question 22

Answer 22

Aneurysmal bone cyst

(“soap bubble appearance”)

Question 23

Answer 23

Interosseous lipoma

Question 24

Answer 24

Intraosseous Lipoma

(usually in the calcaneus, they’re found in the neutral triangle with a central calcified nidus)

Question 25

Answer 25

**simple bone cyst** A solitary, sharply demarcated radiolucent osteolysis may be observed in the calcaneus, without a pathologic fracture

Question 26

Answer 26

**aneurysmal bone cyst** identified as a lytic, expansile lesion with an eccentric shape and septations.

Question 27

Answer 27

**chondroblastoma of calcaneus** located in the posterior calcaneus, which is a lytic expansile mass with a sclerotic margin

Question 28

Answer 28

**intraosseous lipoma** A well-circumscribed lytic lesion is located at the base of the calcaneus neck in the region of the Ward's triangle

Question 29

Answer 29

**Chondromyxoid Fibroma:** large lytic lesion with sclerotic margins and ‘soap bubble’ appearance

Question 30

Answer 30

**Chondrosarcoma** of the calcaneus. The lesion shows a destructive, expansive and pathologic fracture with calcification of the soft tissues

Question 31

Answer 31

**Ewing Sarcoma** (of fibula) aggressive, malignant appearing lytic lesion in the shaft of the fibula. Periosteal reaction: * perpendicular spiculations producing a [sunburst appearance](https://radiopaedia.org/articles/sunburst-appearance-bone-1?lang=us) in the center of the tumor * there is also a laminated appearance towards the distal edge of the tumor producing an [onion-skin appearance](https://radiopaedia.org/articles/multilayered-periosteal-reaction?lang=us) * note the interrupted periosteal reaction ([Codman triangle](https://radiopaedia.org/articles/codman-triangle-periosteal-reaction?lang=us)) at the proximal margin of the lesion

Question 32

Answer 32

Ewings Sarcoma * [Codman triangle](https://radiopaedia.org/articles/codman-triangle-periosteal-reaction?lang=us) (Red arrow) * [Sunburst appearance](https://radiopaedia.org/articles/sunburst-appearance-bone-1?lang=us) (Blue arrows) * [Onion-skin](https://radiopaedia.org/articles/multilayered-periosteal-reaction?lang=us) periosteal reaction (Yellow arrow)