Fetal skeleton

Question 1

what is the most common spinal skeletal dysplasia

Answer 1

platyspondyly (short flat ribs)

Question 2

most common lethal skeletal dysplasia

Answer 2

thanatrophoric dysplasia

Question 3

hitchhiker thumb is seen in (2)

Answer 3

• diastrophic dysplasia

- short rib polydactyly syndrome

Question 4

hitch hiker thumb and club foot

Answer 4

diastrophic dysplasia

Question 5

curved femur and platyspondyly (and narrow thorax + micromelia)

Answer 5

type 1 thanatrophoric

Question 6

straight femur and cloverleaf skull (and narrow thorax + micromelia)

Answer 6

type 2 thanatrophoric

Question 7

most common nonlethal skeletal dysplasia

Answer 7

achondroplasia

Question 8

skeletal dysplasia where there is hypomineralization of the vertebrae, and the skull is not affected

Answer 8

achondrogenesis type II

Question 9

rhizomelia, acromelia, macrocephaly

trident hand

Answer 9

achondroplasia

Question 10

fractured ribs may be associated with (2)

Answer 10

• osteogenesis imperfecta

- achondrogenesis type I

Question 11

hypomineralization and severe limb shortening

Answer 11

achondrogenesis

Question 12

trident hand is associated with

Answer 12

achondroplasia

Question 13

form of achondroplasia compatible with life

Answer 13

heterozygous achondroplasia

Question 14

no rib fractures are seen in

Answer 14

achondrogenesis type II

Question 15

micromelia, short ribs, narrow thorax, polydactyly

Answer 15

short rib-polydactyly syndrome

Question 16

skeletal dysplasia with the most severe degree of limb shortening

Answer 16

achondrogenesis

Question 17

most common anomaly associated with fetal fractures

Answer 17

osteogenesis imperfecta

Question 18

type 2 thanatrophoric presents as (4)

Answer 18

• straight femur
• cloverleaf skull
• narrow thorax
• micromelia

Question 19

Achondrogenesis type I findings (4)

Answer 19

• hypomineralized skull
• hypomineralized skeleton
• rib fractures
• micromelia

Question 20

type 1 thanatrophoric presents as (4)

Answer 20

• curved femur
• platyspondyly
• micromelia
• narrow thorax

Question 21

platyspondyly

Answer 21

flattened spinal bone

Question 22

hypomineralized skull and normal spine is seen in

Answer 22

type 2 osteogenesis imperfecta

Question 23

Achondrogenesis type II findings (4)

Answer 23

• hypomineralization of the vertebrae

- skull not affected

Question 24

club foot associated with (4)

Answer 24

• trisomy 18
• oligohydramn
• skeletal dysplasia
• spina bif

Question 25

how does rockerbottom foot present as

Answer 25

convex foot

Question 26

rockerbottom foot associated with what chromosomal abnormality

Answer 26

trisomy 18

Question 27

sandal foot associated with what chromosomal abnormality

Answer 27

trisomy 21

Question 28

polydactyly is associated with which chromosomal abnormality

Answer 28

trisomy 18
trisomy 13
meckel-gruber syndrome (cystic kidneys, encephalocele, polydactyly)

Question 29

clenched hand is associated with which chromosomal abnormality

Answer 29

trisomy 18

Question 30

syndactyly

Answer 30

fusion of two or more digits

Question 31

cinodactyly

Answer 31

inward curvature of 5th digit

Question 32

clubhand appearance

Answer 32

radial ray defect

Question 33

caudal regression syndrome is strongly assoc with

Answer 33

poorly controlled diabetes meillitus

Question 34

failure of normal vascular supply to the aorta causes

Answer 34

sirenomelia

Question 35

rhizomelia

Answer 35

shortening of proximal segment (femur, humerus)

Question 36

mesomelia

Answer 36

shortening of middle segment (radius, ulna, tib, fib)

Question 37

acromelia

Answer 37

shortening of distal segment (hands and feet)

Question 38

micromelia

Answer 38

shortening of entire limb

Question 39

IUGR vs skeletal dysplasia - how to differentiate

Answer 39

use femur length to foot length ratio

severe IUGR ratio is normal (both reduced)

with skeletal dysplasa, femur length:foot length ratio decreases