Bones, Joints, Soft Tissue

Question 1

What disorder causes dwarfism? What is the mutation causing this? Inheritance?

Answer 1

achondroplasia
FGF3 receptor mutation
Aut. Dominant (most are new mutations and not inherited)

Question 2

Pathogenesis of achondroplasia?

Answer 2

failure of epiphyseal cartilage formation

halts chondrocyte prolif. and differentiation

Question 3

Laron dwarfism mech.

Answer 3

defective growth hormone receptor

Question 4

Osteogenesis imperfecta inheritance and mutation

Answer 4

aut. dom.

mut. in gene for type 1 collagen (COL1A1 ir COL1A2)–> encode type 1 procollagen

Question 5

Mutation in lysyl hydroxylase

Answer 5

Ehlers-Danlos

Question 6

Mutation in fibrillin

Answer 6

Marfan Syndrome

Question 7

recurrent long bone fractures, blue sclera, loose joints, abnormal teeth, poor hearing, child: DX=

Answer 7

osteogenesis imperfecta

type 1 collagen mut.

Question 8

improperly healed fracture withstanding excessive motion and interposition of soft tissue at fracture site–>
*other causes

Answer 8

pseudoarthrosis

*infection, poor perfusion

Question 9

how does precocious puberty affect growth?

Answer 9

premature closure of epiphyseal plates–> short stature

Question 10

viable bone surrounding necrotic bone in osteomyelitis

Answer 10

involcrum

Question 11

what do you call the necrotic bone in osteomyelitis?

Answer 11

sequestrum

Question 12

multiple lytic lesions + keratin-positive cells

Answer 12

metastatic carcinoma

• most common cancer of bone
• spine most likely location
• hematogenous spread

Question 13

What type of metastatic bone cancer produces mostly lytic lesions?

Answer 13

thyroid, GI, kidney, neuroblastoma

Question 14

Metastatic cancers that cause blastic lesions?

Answer 14

prostate, breast, lung, stomach

Question 15

What is another name for “marble bone”/Albers-Schonberg disease?

Answer 15

osteopetrosis

Question 16

failure of osteoclastic bone resorption, most commonly aut. rec., retention of primary spongiosum with cartilage cores, lack of funnelization of metaphysis, thickened cortex

Answer 16

osteopetrosis

Question 17

spontaneous fracture of femoral head + hx of Crohn’s + resection of bowel + thickened osteiod –>

Answer 17

osteomalacia = impaired mineralization of osteiod

Question 18

mutation behind osteosarcoma? age group?

Answer 18

Rb tumor suppressor mut.

10-20 y.o.

Question 19

incomplete rim of reactive bone adjacent to site where it is lifted from cortical surface by tumor (Codman triangle), lytic lesion in metaphysis, elevated alk. phos. in a young man. DX

Answer 19

osteosarcoma

Question 20

underlying pathology of Legg-Calve-Perthes disease

Answer 20

avascular osteonecrosis (=death of bone and marrow without infection)
causes: trauma, thrombi, emboli, corticosteroids

Question 21

osteonecrosis of femoral head in kids

Answer 21

Legg-Calve-Perthes disease

Question 22

most common location of hematogenous ostemyelitis

Answer 22

metaphysis of a long bone

Question 23

proximal phalangeal joint: pannus + synovial cell hyperplasia + lymphoid follicles =

Answer 23

rheumatoid arthritis

Question 24

term for necrotic bone in osteomyelitis

Answer 24

sequestrum

Question 25

9 y.o., 2 wks hip pain, febrile, elevated ESR, X-ray: mottled radiolucent defect in upper femur with abundant periosteal new bone formation; fine needle aspiration shows neutrophils and cocci: Dx?

Answer 25

osteomyelitis

Question 26

morning stiffness + painful, swollen, warm finger joints + narrowing of joint spaces + lymphoid follicles + synovial hyperplasia; what kind of Ab will be present?

Answer 26

polyclonal Ab against Fc portion of IgG (Rheumatoid arthritis)

Question 27

55 y.o. man + pain in arm + elevated Ca and PTH + multiple small bone cysts + giant cells in cellular fibrous stroma; what is it?

Answer 27

osteitis fibrosa cystica from hyperparathyroidism (causes increased bone resorption)

Question 28

fibrosis with reactive woven bone and hemosiderin-laden macrophages, and giant cells =

Answer 28

brown tumor/ osteitis fibrosa cystica

Question 29

67 y.o. develops bow legs and hearing loss and bones show prominent CEMENT LINES and increased osteoblastic and clastic activity. Dx?

Answer 29

Paget's Disease! increased risk for osteogenic sarcoma *mosaic bone formation

Question 30

HLA___ is assoc. with Reiter Syndrome

Answer 30

HLA-B27

Question 31

pathogenesis of osteopenia in postmenopausal women

Answer 31

increased osteoclast activity

Question 32

Type 1 osteoporosis pathogenesis

Answer 32

increase in osteoclast activity from estrogen withdrawal

Question 33

Type 2 osteoporosis pathogenesis

Answer 33

decreased osteoblast activity

Question 34

Ewing Sarcoma translocation

Answer 34

t(11:22)

Question 35

young boy + swelling of tibia + destructive process with indistinct borders and onion skin pattern of periosteal bone + small blue cells + PAS +

Answer 35

ewing sarcoma

Question 36

age 2-5 + radiolucent bony lesions in calvaria, ribs, pelvis, scapulae + possible exopthalmos + crusty red, weepy skin lesions at hairline and extenso surfaces, abdomen, soles of feet

Answer 36

Hand-Schuller-Christian disease (type of langerhans cell histiocytosis)

Question 37

small, painful benign lesions of bone composed of osseus tissue surrounded by halo of reactive bone formation + age 5-25 + spherical hyperemic tumor + nocturnal pain

Answer 37

osteoid oseoma | relieved by NSAIDs!

Question 38

locally aggressive neoplasm composed of multinucleated, osteoclastic giant cells

Answer 38

Giant cell tumor

Question 39

benign neoplasm histologically similar to osteoid osteoma but larger with no nocturnal pain of relief from NSAIDs

Answer 39

osteoblastoma

Question 40

soft tissue tumor with foci of histiocytoma differentiation + common post-radiation therapy + variable morphologic pattern: spindle shaped cells in irregularly whorled (storiform) pattern

Answer 40

malignant fibrous histiocytoma

Question 41

soft tissue mass with spindle shaped mesenchymal cells and cuboidal epithelial-like cells (keratin +)

Answer 41

synovial sarcoma

Question 42

Ollier disease=

Answer 42

Enchondromatosis

Question 43

numerous cartilaginous (hyaline) masses that lead to bony deformities

Answer 43

Ollier disease

Question 44

Enchondromatosis increases risk for what?

Answer 44

chondrosarcoma