Caudal Regression Syndrome, secondary to maternal diabetes

2-year-old male with a history of caudal regression syndrome. There is agenesis of the sacrococcygeal region with aplasia of the lower lumbar spine and hypoplasia of the mid to upper lumbar spinal region. Caudal regression syndrome is rare with an incidence of 1:100,000. While the majority of cases are sporadic, familial cases are associated with VACTERL and Currarino triad syndromes. There is no gender predilection. Caudal regression syndrome is secondary to an early gestational insult, earlier than the fourth gestational week. Imaging features include a characteristic wedge-shaped cord terminus, as in this case. Other imaging features which may be seen, but are not present in this case, include an elongated and tethered conus with a thickened filum terminale or possibly an intraspina lipoma. Treatment and prognosis depend on the regression extent.