Details
19 week gestational fetus. Brachymelia identified on ultrasound.
Robinow syndrome is a rare heterogenetic syndrome which affects a variety of organ systems throughout the body. Radiologically, the recessive form of the syndrome is distinguished by mesomelic dwarfism, segmentation abnormalities of the spine, and fused ribs. The recessive form - as seen in this subject - is more severe and is often fatal. It is caused by a mutation to the gene ROR2, which codes for receptor protein tyrosine kinase and type I transmembrane protein, which is involved in chondrocyte formation and is therefore crucial for proper formation of the cartilaginous skeletal anlage.
The radiographs show moderate mesomelic brachymelia, particularly of the forearms, and shorter ulnae than radii. All long bones are shortened and thickened. There is brachydactyly with variable ossification of the metacarpals and phalanges, particularly in the feet. Note the short, cylindrical metacarpals and bullet shaped phalanges in the hands.
There are multiple spinal segmentation abnormalities, including hemivertebrae, irregular vertebral fusion, and both sagittal and coronal clefts. This is presented quite strikingly in the thoracic spine. Genitalia are ambiguous, but with both male gonads and karyotype.
The ribs are severely malformed, with fusions, irregular flaring, and missing ribs.
“Fetal facies” with a prominent forehead, flat nasal bride, upturned nose, and triangular mouth, can be seen in the specimen photographs.
This image shows a frontal view radiograph. See related content for:
- radiographs: lateral view, hands and feet
- specimen photographs: frontal view, face, and hands.
See related content for references:
1) Patton MA., Afzal AR. J Med Genet. 2002 May;39(5):305-10
