26 morph

Question 1

bone lacks medullary canal = no hematopoetic marrow

Answer 1

osteopetrosis

Question 2

erlenmeyer flask deformity

Answer 2

osteopetrosis

Question 3

neural foramina small

Answer 3

osteopetrosis

Question 4

nml bine, but decreased quantity of trabecular bone

Answer 4

osteoporosis

Question 5

Mosaic pattern of lamellar bone. ‘Jigsaw puzzlelike’ d/t unusually prominent cement lines orienting lamellar bone

Answer 5

sclerotic phase Paget Disease (osteitis deformans)

Question 6

‘Cotton wool’ appearance.

Answer 6

Paget Disease (osteitis deformans)

Question 7

wedge shaped empty lacunae that are surrounded by ruptured adipocytes, which can have assoc fat saponification (may remain for life).

Answer 7

Osteonecrosis (avascular necrosis)

Question 8

tissue paper cells

Answer 8

goucher dis: Osteonecrosis (avascular necrosis)

Question 9

Involucrum: .
o : . (pic)
o : .

Answer 9

pyogenic osteomelitis

=subperiosteal new bone encasing the inflamm focus

Question 10

Brodie abscess

Answer 10

pyogenic osteomelitis

=small, walled off intracortical abscess

Question 11

gummas

Answer 11

Skeletal Syphilis (congenital)

Question 12

well circumscribed nodules of translucent cortical, interlacing woven bone (nidus) rimmed by osteoblasts; surrounded by vasc and loose CT

Answer 12

osteoid osteoma and osteobalstoma

Question 13

formation of bone by tumor cells*; fine, lace-like pattern or may be deposited in broad sheets

Answer 13

osteosarcoma

Question 14

sessile/peduncleated solitar, cartilage cap mass; cortex of the stalk merges with the cortex of the host bone so that the 2 medullary cavities are continuous.

Answer 14

Osteochondroma (exostosis)

Question 15

multiple cartilaginous tumors of hands and feet

Answer 15

chondroma

Question 16

 Translucent gray-blue tumors, < 3cm with limited growth potential.
 Well-circumscribed nodules of benign hyaline cartilage.
 Peripheral portion of the nodules may undergo enchondral ossification and the center can calcify and infarct.

Answer 16

chondroma

Question 17

spindle cell hemangioma

Answer 17

maffucci synd

Question 18

malig tumor producing cartilage on the axial skeleton (pelvis, shoulder, ribs)

Answer 18

chondrosarcoma

Question 19

 Transluscent cartilage w gelatinous or myxoid matrix (may ooze from cut surfaces).
 Spotty calcifications.

Answer 19

chondrosarcoma

Question 20

homer-Wright rosettes

Answer 20

Ewing Sarcoma Family Tumors (ESFT) (including PNET)

Question 21

tumor rich in glycogen, hem, necrosis

Answer 21

Ewing Sarcoma Family Tumors (ESFT) (including PNET)

Question 22

onion-skinning

Answer 22

Ewing Sarcoma Family Tumors (ESFT) (including PNET)

Question 23

expansile lesion w well defined margins at metaphysis of long bones

Answer 23

Aneurysmal Bone Cyst (ABC)

Question 24

.5cm on metaphysis of distal femur, prosimal tibia, storiform (pinwheel) pattern and foamy mfs clustered in giant cells

Answer 24

Fibrous Cortical Defect (metaphyseal fibrous defects) and non-ossifying fibromas

Question 25

 Curvilinear trabeculae of woven bone that resemble Chinese characters.
 Cystic degeneration, hemorrhage and foamy Mf.

Answer 25

Fibrous Dysplasia

Question 26

Mature adipocytes and scattered spindle cells w hyperchromatic nuclei

Answer 26

well-diff liposarcoma

Question 27

Myxoid matrix, ‘chicken wire’ vessels, round cells, lipoblasts.

Answer 27

myxoid liposarcoma

Question 28

eos cells interecting at right angles

Answer 28

leiomyoma

Question 29

o Pleomorphic eosinophilic spindle cells.

o Blunt-ended hyperchromatic nuclei in interweaving fascicles.

Answer 29

leiomyosarcoma