Chapter 29: Normal and Abnormal Fetal Limbs Flashcards
shortening of the most distal portion of a fetal limnb
acromelia
abnormal shortening of the middle portion of a limb
mesomelia
abnormally short limb
micromelia
flattened vertebral bodies with a decreased distance between the end plates
platyspondyly
condition of having more than the normal number of digits on a hand or foot
polydatyly
shortening of the most proximal portion of a fetal limb
rhizomelia
fusion of soft tissue or bony segments of fetal digits
syndatyly
abnormal position of the fetal foot and ankle
talipes
Achondrogenesis is ______ dominant. (limb shortening)
micromelia
Achondroplasia is _____ dominant. (limb shortening)
rhizomelia
Asphyxiating thoracic dysplasia is _____ dominant. (limb shortening)
mesomelia
Camptomelic dysplasia is _____ dominant. (limb shortening)
mesomelia, rhizomelia
Congenital hypophosphatasia is _____ dominant. (limb shortening)
micromelia
Ellis-van Creveld is ______ dominant. (limb shortening)
rhizomelia
Hypophosphatasia is ______ dominant. (limb shortening)
micromelia
Osteogenesis imperfecta is _______ dominant. (limb shortening)
micromelia
Short-rib polydatcyly is ______ dominant. (limb shortening)
micromelia
Thanatophoric dysplasia is _____ dominant. (limb shortening)
micromelia
Skeletal dysplasias associated with curved or bowed long bones
camptomelic dysplasia
hypophosphatasia
osteogenesis imperfecta
thanatophoric dysplasia
skeletal dysplasias associated with hypomineralization
achondrogenesis
camptomelic dysplasia
hypophosphatasia
osteogenesis imperfecta
short-rib polydactyly syndrome
thanatophoric dysplasia
skeletal dysplasias associated with narrow thorax
achondrogenesis type I
achondroplasia
asphyxiating thoracic dysplasia
camptomelic dysplasia
short rib polydatyly syndrome
thanatorphic syndrome
Skeletal dysplasias associated with polydactyly
asphyxiating thoracic dysplasia
Ellis-van Creveld syndrome
short rib polydactyly syndrome
VACTERL association
Skeletal dysplasias associated with radial aplasia or hypoplasia
Holt-Oram syndrome
Thrombocytopenia-absent radius syndrome
VACTERL association
Skeletal dysplasias associated with bone fractures
achondrogenesis
hypophosphatasia
osteogenesis imperfecta
Skeletal dysplasias associated with heart disease
Asphyxiating thoracic dysplasia
Ellis-van Creveld Syndrome
Holt-Oram syndrome
Short-rib polydactyly syndrome
VACTERL association
Skeletal dysplasias associated with macrocephaly
achondroplasia
camptomelic dysplasia
thanatorphic dysplasia
Anomalies associated with thanatorphic dwarfism
hypomineralization
macrocephaly
frontal bossing
narrow thorax
Anomalies associated with Achondroplasia
macrocephaly
hydrocephaly
frontal bossing
narrow thorax
Anomalies associated with achondrogenesis
hypomineralization
narrow thorax
bone fractures
micromelia
micrognathia
Anomalies associated with short rib polydactyly syndrome
narrow thorax
hypomineralization
poldactyly or syndactyly
gastrointestinal/genital/urogenital malformations
cleft lip/palate
Anomalies associated with asphyxiating thoracic dysplasia
narrow thorax
polydactyly
pelvic/renal anomalies
anomalies associated with Ellis-van Creveld syndrome
polydactyly
short limbs
narrow thorax
heart malformations
dysplastic nails/teeth
abnormal upper lip
anomalies associated with osteogenesis imperfecta
curved or bowel long bones
hypomineralization
bone fractures
bell-shaped thorax
anomalies associated with camptomelic dysplasia
curved or bowed long bones
hypomineralization
macrocephaly
bell-shaped thorax
micrognathia
hydrocephalus
cleft palate
pyelectasis
hypoplastic scapulae
anomalies associated with congenital hypophosphatasia
hypomineralization
curved or bowed long bones
short bones
anomalies associated with dystosis
abnormal ossification
craniofacial dystosis
syndactyly
Fetal limb buds visualize as early as ___ weeks with endovaginal ultrasound
8
The long bones fully develop between ___-____ weeks
7-12
Primary ossification centers image at ___ weeks
10
The bones in the hand and feet are developed between the __ and ___ weeks
11-13
Movement of limbs and terminal phalanges can be visualized at __ weeks
11
The femur, humerus, radius, ulna, tibia, and fibula can be accurately measured at ___ weeks.
12
The high amplitude reflection of bone is generated by the _____ content.
calcium
epiphyes
secondary ossification centers
The epiphyes are separated from the shaft of the fetal long bone by a layer of ______
cartilage
The distal femoral epiphyes is visualized between __ and __ weeks
32, 34
The proximal tibial epiphysis is visualized at approximately ___-__ weeks
34, 35
The proximal humeral epiphyses is visualized at ____
term
Ossification during second trimester includes the bones:
metacarpals, phalanges, talus, calcaneus, pubis of ankle
After birth ossification bones include:
carpal and tarsal bones
most commonly measured long bone
femur
The femur should look ____, _____, and _______.
straight
symmetrical
evenly ossified
The femur has a straight appearance _____, and a bowed appearance _____.
laterally
medially
The femur should be measured from outer margin to outer margin with the junction of the bone and cartilage excluding _____ and ____.
femoral head
distal epiphyses
The femur grows approximately __ mm from 14-27 weeks
3
The femur grows approximately __ mm from third trimester to term.
1
The accuracy of the femur bone measurement in the second trimester is:
+/- 1 week
The accuracy of the femur bone measurement in the third trimester is:
+/- 3.5 weeks
Femoral length varies with:
maternal height, weight, ethnicity
The femur and the _____ visualize the same on sonographic imaging.
humerus
The tibia is ____ and oriented _____.
thicker
medially
The ulna is longer than the _____
radius
The fetal hand should be identified in ____ and _____.
flexion and extension
abnormal development of cartilaginous and osseus tissues; results in bones that appear shortened, thin, deformed, fail to form at all
skeletal dysplasias
sharp angulations in midshaft of bone
fracture
bones that appear thin or unevenly mineralized
abnormal skeletal mineralization
proximal portion of extremity shortened i.e. humerus, femur
rhizomelia
shortening of middle or intermediate segment of extremity, i.e. radius, ulna, fibula, tibia
mesomelias
shortening of distal portion of an extremity, i.e. hands and feet bones
acromelia
shortening of entire extremity
micromelia
disorder defined as premature fusion of one or more cranial sutures
craniosynostosis
Craniosynostosis is caused by:
external forces
Most severe form of craniosynostosis
Kleeblattschadel or cloverleaf deformity
Craniosynostosis can be associated with:
thanatorphoric dysplasia
abnormally small lower jaw, abnormally shaped ears, frontal bossing
micrognathia
Lethal skeletal dysplasias are often accompanied by:
pulmonary hypoplasia
reduction in number of airways, lung cells, and alveoli
pulmonary hypoplasia
Most common sonographic appearance of pulmonary hypoplasia
bell-shaped narrow thorax
FL/AC of less than 0.16 or a TC/AC of less than 0.79 indicates:
hyperplastic thorax
most common form of lethal skeletal dysplasia
thanatorphic dysplasia
Thanatophoric dysplasia is transmitted ______ fashion by mutations of fibroblast growth factor receptor 3
autosomal dominant
Type __ thanatorphic dysplasia is the most common
I
extreme rhizomelia, bowed long bones with a “telephone receiver” appearance, normal trunk length, platyspondyly, and frontal bossing
Type I thanatorphic dysplasia
straighter long bones, taller vertebral bodies, cloverleaf skull
Type II thanatorphic dysplasia
Narrow thorax with a protruding abdomen in thanatorphic dysplasia is said to have a _____ appearance
champagne cork
most common nonlethal type of dwarfism
achondroplasia
Achondroplasia is inherited in a _______ fashion caused by spontaneous mutation in the FGFR3 gene.
autosomal dominant
Characteristic features of achondroplasia:
rhizomelic limb bowing
frontal bossing
low nasal bridge
trident hand
increased space between third and fourth digits
trident hand
Type I achondrogenesis known as _________.
Parenti-Fraccaro
Achondrogenesis is inherited in a _______ fashion
autosomal recessive
Parenti-Fraccaro achondrogenesis is characterized by:
extreme micromelia
large head
short and thin ribs that may have fractures
poor ossification of skull, spine, and pelvic bones
Type II achondrogenesis is known as ______.
Langer Saldino
Type II achondrogenesis Langer-Saldino is inherited in a _______ fashion
autosomal dominant
Type II Langer-Saldino is characterized by:
prominent forehead
flat face with micrognathia
absence of rib fractures
less severe mineralization
less severe micromelia
Short tib polydactyly syndrome is inherited in a _____ fashion
autosomal recessive
short rib polydactyly syndrome is characterized by:
micromelic dwarfism
short and horizontal ribs
narrow thorax
polydactyly
3 types of short rib polydactyly syndrome
Saldino-Noonan (type I)
Majewki (type II)
Naumoff (type III)
Fetuses affected by short rib polydactyly syndrome die within a few hours after birth due to _____
pulmonary hypoplasia
Asphyxiating thoracic dysplasia is also referred to as
Jeune Syndrome
Asphyxiating thoracic dysplasia is inherited in a _______ fashion.
autosomal recessive
Asphyxiating thoracic dysplasia is characterized by:
extremely narrow thorax
rhizomelic limbs
polydactyly
pelic and renal anomalies
Ellis-van Creveld syndrome is also referred to as:
chondroectodermal dysplasia
Ellis-van Creveld syndrome is inherited in a ______ fashion.
autosomal recessive
This syndrome is frequently found in communities where inbreeding is prominent
Ellis-van Creveld
Ellis-van Creveld is characterized by:
short limbs
short ribs
narrow thorax
polydactyly
dysplastic nails and teeth
abnormalities of upper lip
congenital heart disease
rare, inheritable connective tissue disorder
osteogenesis imperfecta
Osteogenesis imperfecta is caused by defects in _____ quality or quanity
type I collagen
decreased mineralization of bone and bone fragility
osteogenesis imperfecta
Osteogenesis imperfecta is characterized by:
long bone and rib fractures
extraskeletal abnormalities (blue sclera, hearing impairment)
abnormal decrease in quantity of collagen produced, milder forms, autosomal dominant pattern, femoral bowing sonographically in utero, usually of normal stature
Type I osteogenesis imperfecta
Most severe form of osteogenesis imperfecta
Type II
autosomal recessive, characterized by reduced echogenicity of long bones, concave ribs from rib fractures, long bones may appear thickened and angulated, thorax bell-shaped appearance, skull lacks ossification,
type II osteogenesis imperfecta
autosomal dominant or recessive, limb bowing in utero, multiple fractures at birth that lead to progressive bone deformities through adolescence,
Type III osteogenesis imperfecta
mildest form, does not present until later in life, autosomal dominant, short stature, premature osteoporosis later in life
Type IV osteogenesis imperfecta
rare form of short-limbed dwarfismn
camptomelic dysplasia
Camptomelic dysplasia is inherited in a ______ fashion caused by a mutation in the SOX9 gene
autosomal dominant
Camptomelic dysplasia is characterized by:
short and bowed limbs
short trunk
large head
bell-shaped chest
rare inherited disease of defective bone mineralization
congenital hypophosphatasia
Congenital hypophosphatasia is characterized by:
low or absent tissue- nonspecific alkaline phophatase
Type I congenital hypophosphatasia is inherited in a ______ fasion
autosomal recessive
Type I congenital hypophophatasia is characterized by:
overall reduction in ossification
short, bent bones
skull easily compressed
spurs along midshaft or long bones, knees, elbows
lethal
Type II congenital hypophophatasia is inherited in a _______ fashion
autosomal dominant
Type ___ congenital hypophosphatasia can be visualized prenatally while type __ congenital hypophosphatasia is not detected until later in life.
I
II
any condition characterized by abnormal ossification
dystosis
widening of the cranial fontanelles with an increase in the lateral aspect of the cranium
cleidocranial dystosis
Cleidocranial dystosis is associated with:
hypoplastic clavicles
spinal abnormalities
hypoplastic middle and distal phalanges
Craniofacial dystoses is commonly associated with _____
craniosynostosis
Apert syndrome is characterized by:
craniosynostosis
midfacial hypoplasia
bilateral syndactyly
bilateral syndactyly is also known as _____
mitten hand
A persistently clenched hand with overlapping index finger is commonly associated with _____
trisomy 18
Trident hand is characteristically found in:
achondroplasia
presence of extra digits on hands or feet
polydactyly
One of the most common hand anomalies
polydactyly
Preaxial polydactyly
radial (thumb) side
Postaxial polydactyly
ulnar (little finger) side
Central polydactyly
three central digits
Most commonly encountered polydactyly
postaxial polydactyly
Least commonly encountered polydactyly
central polydactyly
congenital absence or incomplete development of one or more limbs or segments of limbs
limb reduction abnormality
absence of a bone
aplasia
absence of one or more limbs
hypoplasia
absence of one or more limbs
amelia
absence of one or more extremities below the elbow or knee
hemimelia
absence of one or more hands
acheira
absence of one or more feet
apodia
absence of one or more digits
adactyly
absence of the proximal portion of an extremity with hand or feet attached to the trunk
phocomelia
absence of part of a limb
meromelia
Holt-Oram syndrome is inherited in an _______ fashion
autosomal dominant
Holt-Oram syndrome is characterized by:
skeletal and cardiac abnormalities
Holt-Oram mainly affects the ___ limbs
upper
thumb includes three phalanges instead of two
triphalangeal thumb
Most common cardiac defect seen with Holt-Oram syndrome
atrial septal defect
Thrombocytopenia-absent radius syndrome is inherited in an _____ fashion
autosomal recessive
associated with decreased platelets
thrombocytopenia-absent radius syndrome
bilaterally absent radii but with five fully formed digits
thrombocytopenia-absent radius syndrome
Thrombocytopenia-absent radius syndrome is often associated with:
congenital heart disease
combination of associated defects: vertebral, anorectal, cardiac, trachesophogeal, renal, limb
VACTERL association
VACTERL
vertebral
anorectal
cardiac
tracheoesophageal
renal
limb
at least ___ abnormalities need to be present to be considered a VACTERL association
3
Club foot is also known as:
talipes
fetal foot being excessively medially deviated so that the bone of the foot lies in the same plane as the lower leg
clubfoot
Club foot is commonly seen as deformation caused by:
fetal movement restriction
group of fetal abnormalities that range from constriction rings and edema of the digits to multiple, complex anomalies of different portions of the fetal body
amniotic band sequence
Sonographic appearance of bands
linear density
attached from one uterine wall to another or attached from uterine wall to a fetal part
mermaid syndrome
sirenomelia
Sirenomelia is associated with:
maternal diabetes
monozygotic twinning
maternal cocaine use
fusion of both lower extremities
sirenomelia
Sirenomelia is thought to be caused by:
vascular steal phenomenonp
persistent vessel from an early embryonic vascular system that diverts blood flow, causing severe ischemia of caudal portion of fetus
vascular steal phenomenon
partial or complete agenesis of the sacrum, lumbar, vertebrae, distal spinal cord, and lack of growth of caudal region
caudal regression syndrome
Maternal conditions associated with limb abnormalities
maternal disease
medications
substance abuse
exposure to radiation or industrial chemicals
Limb measurements below the 10th percentile are associated with:
IUGR
fetal alcohol syndrome
illicit drug abuse
congenital or chromosomal abnormality
Environmental factors of the fetus that can cause limb anormalities
oligiohydramnios
uterine tumors
Mullerian anomalies
Mothers with insulin-dependent diabetes are at a higher risk for having a fetus with:
caudal regression syndrome
Mothers who have hyperthyroidism are at a higher risk for having a fetus with:
craniosynostosis
Thalidomide (an anti-nausea medication) can cause:
phocomelia
Warfarin can cause:
craniosynostosis
Primary ossification centers of the limbs image as early as __ weeks
10
Long bone epiphysis visualize by __ weeks, helping in determination of fetal maturity.
35
On average, the fetal femur grows __ mm a week up to week 27, slowing to __ mm a week for the rest of gestation.
3
1
_____ occur with other, often fatal fetal anomalies
skeletal dysplasias
The autosomal dominant ______ results in an individual with a large head, bowed limbs, trident hands, and a low nasal bridge
achondroplasia
All three types of the lethal ______ syndrome include findings of a narrow thorax, polydactyly, short, horizontal ribs, micromelic dwarfism, and pulmonary hypoplasia
short rib polydactyly syndrome
A fetus with an extremely narrow thorax, rhizomelic limbs, polydactyly, and pelvic and renal anomalies describes:
asphyxiating thoracic dysplasia
Short limbs, short ribs, and a narrow thorax, polydactyly, dysplastic nails and teeth, abnormalities of the upper lip and congenital heart disease describe:
Ellis-van Creveld syndrome
Prenatal bone bowing and fractures describes characteristics of:
osteogenesis imperfecta
Short and bowed limbs, a short trunk, a large head, and a bell-shaped chest desribe a type of dwarfism called:
camptomelic dysplasia
The main characteristic of congenital hypophosphatasia is:
a lack of bone mineralization
Apert syndrome is a form of _____
dystosis
Fusion of the lower extremities is the result of a vascular steal phenomenon and is part of _____
sirenomelia
Between 32 and 35 weeks, the epiphyseal region of the _____ can be seen sonographically
femur
The normal fetal hand should be visualized in:
flexion and extension
A short limb dysplasia affecting the humerus is:
rhizomelia
Shortening of the entire limb is known as:
micromelia
Micrognathia is:
an abnormally small lower jaw
A type of skeletal dysplasia demonstrating sonographically as a narrow bell-shaped thorax is most likely:
pulmonary hypoplasia
Characteristics of rhizomelic limb bowing, frontal bossing, a low nasal bridge, a “trident” configuration of the hand with possible macrocephaly, and hydrocephaly may be noted in:
achondroplasia
Select the syndrome with the best prognosis for living into adulthood
a. asphyxiating thoracic dysplasia
b. thanatophoric dysplasia
c. achondrogenesis
d. ellis van creveld syndrome
d
Central polydactyly affects the:
three middle digits of the hand
The absence of one or more hands:
acheiria
Holt-Oran syndrome demonstrates abnormalities of the skeletal system and:
cardiac system
Amniotic band sequence is believed to be related to:
polydactyly
The “mermaid syndrome” is rare and lethal and also known as
sirenomelia
Fetal hands and feet anomalies include all but:
a. extra fingers
b. clubbing
c. ischemia
d. finger reduction
c
Congenital hypophophatasia is an inherited disease related to:
defective bone mineralization
Maternal hyperthyroidism contributes to:
craniosynostosis
What is the most likely cause of digit and limb amputation?
amniotic bands
The most common cause of skeletal deformities is:
toxic agents
Polyhydramnios is common in all except:
a. camptomelic dysplasia
b. TD
c. short rib-polydatyly syndrome
d. achondroplasia
d
Select the thickest extremity long bone
a. tibia
b. ulna
c. fibula
d. radius
a
An amniotic sheet appears as a membranous pillar within the amniotic fluid and is characterized by a ______ that projects into the amniotic cavity.
free edge
Primary ossification centers of limbs are visualized at ___ weeks.
10
Long bone epiphysis visualizes by __ weeks, helping in determination of fetal maturity.
35
Skeletal dysplasia is the abnormal development of the ______ and osseus tissues.
cartaliginous
The premature fusion of one or several cranial sutures is ______
craniosynostosis
_____ is a condition characterized by abnormal ossification.
Dystosis
A dysplasia with an extremely poor prognosis owing to respiratory complications from hypoplastic lungs and micrognathia is ______
camptomelic dysplasia
Osteogenesis imperfecta is rare, inheritable, and related to defects in _____ quality or quantity.
type I collagen
Meromelia is a(n) ______ or part of a limb
absence
A fetal forearm with an absent radius is frequently noted to have a radially deviated hand that appears as a _____
clubhand
VACTERL association is defined as:
vertebral
anorectal
cardiac
tracheoesophageal
renal
limb
clubfoot is frequently caused by ______ or other conditions that limit fetal movements.
oligohydramnios
Amniotic bands, known as ____, are associated with medical procedures involved the uterine _____ and intrauterine infections
synechaie
endometrium
Lower extremity fusion is postulated to be caused by a ______ steal phenomenon
vascular
Skeletal dysplasias are mostly ____ to the fetus
fatal
Osteogenesis imperfecta causes prenatal bone ______ and fractures
fragility
A fetus with an extremely narrow thorax, rhizomelic limbs, polydactyly, pelvic anomalies, and renal anomalies describes ______ dysplasia.
asphyxiating thoracic
Achondrogenesis is lethal because of _____
pulmonary hyoplasia
The femur bone may resemble the _____ bone on fetal sonography
humerus
On average, the fetal femur grows ___ mm a week up to 27 weeks, slowing to __ mm per week for the rest of gestation.
3
1
