Caudal Regression Syndrome

  • Etiology:
    — Neural tube defect with anomalous differentiation of caudal cell mass with resultant abnormal development of caudal vertebral column and spinal cord
    — Caudal cell mass is anlage for distal spinal cord and lumbosacral bony spine and distal gastrointestinal and genitourinary tracts, thus often associated with lumbosacral hypoplasia (caudal regression) and anal atresia or cloaca anomaly and genitourinary anomalies
  • Imaging:
    — Type I: Anomalous differentiation of caudal cell mass, sacral hypoplasia, abrupt wedge shaped or truncated cord termination
    — Type II: Sacral dysplasia and tethered cord with or without syrinx
  • DDX:
  • Complications:
  • Treatment:
  • Clinical:
    — Infant of diabetic mothe
    — Flat buttock characteristic appearance of sacral hypoplasia
    — Currarino triad consists of anorectal malformation – anal stenosis or imperforate anus, sacral malformation – hypoplasia or agenesis or sickle shaped sacrum, presacral mass – sacrococcygeal teratoma or myelomeningocele or lipomyelomeningocele or rectal duplication

Radiology Cases of Caudal Regression Syndrome

AXR and CT of caudal regression syndrome
AXR (above) and axial CT without contrast of the pelvis (below) shows hypoplasia of the lower lumbar spine and complete absence of the sacrum with approximation of the iliac wings in the midline.

Radiology Cases of Caudal Regression Syndrome and Currarino Syndrome

CT and MRI of Currarino syndrome
3D CT of the pelvis (left) shows near complete absence of the lower sacrum with the sacrum having a sickel shape on the right. Midline sagittal T2 MRI of the lumbar spine (middle) shows the conus medullaris to be low in position terminating at L5. Off center sagittal T2 MRI (right) shows a small round low signal intensity lesion anterior to the S2 vertebral body.