Type:
Educational Exhibit
Keywords:
Foetus, Education and training, eLearning, Education, Diagnostic procedure, Ultrasound, Echocardiography, CT, Oncology, Obstetrics (Pregnancy / birth / postnatal period), Foetal imaging
Authors:
H. Pruthi, J. SEN; Rohtak, Haryana/IN
DOI:
10.26044/ecr2019/C-3786
Background
Skeletal dysplasia's are a heterogeneous group of conditions associated with abnormalities of the skeleton ( bone,
cartilage and growth plate- shape,
size,
and density)that manifest as abnormalities of the limbs,
chest,
or skull with evolving phenotypes because of genetic inheritance or new mutations(de novo).
(1)
There are more than 400 TYPES {32 GROUPS}
CLASSIFICATION
A)Lethal vs Non-lethal dysplasia.
B)Rhizo/meso/acro/micromelic.
Four main culprits-Thanatophoric,
Osteogenesis Imperfecta,
Achondroplasia,
and Achondrogenesis ( 67%). (2)
Achondroplasia and Thanatophoric dysplasia(Td) are autosomal dominant whereas Achondrogenesis being autosomal recessive. Osteogenesis imperfecta has both autosomal dominant as well recessive types.
Fetal Skeletal Dysplasia (FSD) Criteria-:
•Any fetus showing femur or humerus length measurements less than 5th centile(-2SD) or head circumference >75 centiles (−3 SD) from the mean in the second trimester (24 weeks).
(difference of 4-6 weeks)
•The femur to foot ratio,
which approaches ONE throughout gestation normally.
Less than one is suspicious for FSD.(3)(4)
• Other findings -:
skull (frontal bossing),face (micrognathia),thorax (barrel-shaped) polydactyly,
vertebral body shape,
polyhydramnios etc.
There are major clues for suspecting type of Fetal skeletal dysplasia as follows-:
- Thorax -extremely small? (Td),
Long and narrow(Jeune).
- Ribs extremely short,
Cleft lip-Srps(urinary tract abnormality).
- Polydactyly – Srps,
CDP or Jeune syndrome.
- Gaps between ribs-Jarcho levin syndrome.
- Fractures present-Osteogeneisis Imperfecta.
- Cardiac anomaly-Ellis Van Creveld.
- Ambiguous genitalia-Camptomelic dysplasia.
- Absent scapula-Camptomelic dysplasia.
- Gastrointestinal abnormalities-Achondroplasia.
- All parts of spine equally effected-Achondrogenesis.
- Absent sacrum-Sacral agenesis.
- Absent clavicle-Costo-Clavicular Dysplasia.