Skeletal System Quiz

Question 1

At approx what week can the ossification center of most of the bones be imaged?

Answer 1

approx 16 weeks

Question 2

what do sonographers have to asses with the skeletal of a fetus?

Answer 2

they asses the shape, size, echogenicity, etc of the forming skull, spine, ribs and extremities.

Question 3

What is BPD (biparietal diameter) measurement

Answer 3

Measures the outer to inner layer of skull

Question 4

What is head circumference measurement?

Answer 4

same level as BPD. Outer circumference

Question 5

Face Profile Mesurement

Answer 5

Nasal bone appears as a bright echo parallel to the echogenic skin interface in the superior aspect of the nose. ‘Equal Sign’

Question 6

Humerus

Answer 6

Long Bone attached to shoulder

Question 7

Radius and Ulna

Answer 7

Radius- shorter bone, THUMB side
Ulna- Longer bone, PINKY side

Question 8

Femur

Answer 8

Measured for GA, attached to acetabulum, Largest bone in leg

Question 9

Tibia & Fibula

Answer 9

Tibia- Larger and taller of calf bones, MEDIAL
Fibula- Thiiner of calf bones, LATERAL

Question 10

Should images be taken in two planes for cervical, thoracic, lumbar and sacral regions?

Answer 10

YES

Question 11

what should be taken in sagittal/long plane for spine?

Answer 11

*Integrity of skin line
*Spine curvatures (Cervical and lumbosacaral)
* Sacral tapering

Question 12

What is the best plane for evaluation

Answer 12

Transverse

Question 13

Why is transverse the best plane for evaluation?

Answer 13

has 2 posterior and 1 anterior element.
Posterior are laminae and Anterior is Centrum

Question 14

what can you see in transverse

Answer 14

*integrity of skin line
*line of vertebral ossification centers

Question 15

Know the abnormal and normal long and trans images on docs

Answer 15

CHECK the DOCS NOW

Question 16

Syndactyly

Answer 16

fusion of digits (soft tissue and/or bony)

Question 17

Polydactyly

Answer 17

more than five digits

Question 18

Amelia

Answer 18

absence of an entire extremity

Question 19

Phocomelia

Answer 19

absent segment of an extremity

Question 20

Micromelia

Answer 20

shortened extremities

Question 21

Acromelia (away)

Answer 21

shortening of distal segment of an extremity (foot, hand)

Question 22

Mesomelia (mid)

Answer 22

shortening of middle segment of an extremity (rad/uln, tib/fib)

Question 23

Rhizomelia (rise)

Answer 23

shortening of proximal segment of an extremity (femur, humerus)

Question 24

If long bones measure > 2 SD below the mean for GA then you should:

Answer 24

Assess bone contour - look for bowing, fractures
Measure all long bones
Estimate degree of ossification of cranium, spine, long bones, ribs
Evaluation of thoracic cavity shape
Evaluate hands/feet for syn/polydactyly, acromelia
Assess face for clefts, frontal bossing
Survey rest of fetus for anomalies

Question 25

what are 3 characteristics that are present in a lethal dysplasia.

Answer 25

1. Severe Micromelia - Long bone measures more than 4 SD below the mean for GA. 2. Presence of a specific feature of a lethal abnormality (for example innumerable fractures with OI Type II). 3. Severely hypoplastic thorax/thoracic cavity- Lungs can not develop so survival is not possible. Sonographically called bell-shaped in coronal, champagne cork in sagittal.

Question 26

Look at sonography images for skeletal dysplasia

Answer 26

abnormal (bell shaped)- coronal view abnormal (Champagne cork)- Long View

Question 27

Thanatophoric Dysplasia

Answer 27

Name means ‘death bearing’. Most common Lethal dysplasia. -Cloverleaf skull =Severe Micromelia (especially rhizomelia - proximal, femur/humerus) -Mild hypomineralization - hypoechoic/marbling -Hypoplastic thorax (but normal trunk)

Question 28

Anencephaly

Answer 28

Congenital absence of cerebral hemispheres and cranial vault. Occurs when the neural tube fails to close by 24 days gestation. The brain stem and base of the skull that form from other structures are present. Sono Appearance: Fetal cranium should be seen sonographically by 15 weeks (usually 12). Polyhydramnios Spina Bifida (associated) Absence of cranial vault and cerebral hemispheres Face and orbits present (Frog-Like Face)

Question 29

Sirenomelia (Mermaid Syndrome)

Answer 29

Presents with lower extremity fusion. Possible abnormal or absent foot structures. Uncontrolled maternal diabetes seems to play a role in the development of this disorder. Associated with bilateral renal agenesis, and other skeletal anomalies. *Bilateral renal agenesis often accompanies this condition.

Question 30

sono appearance of Sirenomelia

Answer 30

-Unilateral femur, or bilateral femurs consistently visualized side by side -Abnormal or absent foot structures -Oligohydramnios due to Bilateral Renal Agenesis -Cardiac Anomalies -Genital Absence -SUA (single umbilical artery)