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Caudal regression syndrome

Case contributed by Dr Naim Qaqish


Primary urinary incontinence

Patient Data

Age: 5 years
Gender: Male

Agenesis of the sacrum is seen below the level of S2.

Thecal sac terminates at S1 level.

The conus medullaris terminates mid-portion of L1 level with a truncated appearance of the conus medullaris.

Normal cauda equina.

Constellation of findings consistent with caudal regression syndrome.

No hydronephrosis.

Distended rectum.

Case Discussion

5-year-old boy with primary urinary incontinence. Referred from his physician to confirm the diagnosis of caudal regression syndrome. 

Caudal regression syndrome is a rare birth defect, in which the fetal development of the lower spine is abnormal.  This disturbance results in symptoms varying from isolated partial agenesis of the coccyx to lumbosacral agenesis and even complete fusion of the lower limbs.

Mild cases may not be identified until adulthood. Severe cases are usually identified in utero or at birth.

The exact cause is unknown, but in the antenatal setting, it is associated with maternal diabetes type I or type II, with higher incidence in patients with type I.  

Sacral agenesis can be part of the syndrome. Polyhydramnios, and VACTERL complex may also be associated.

MRI is useful to assess canal stenosis, and appearances can vary depending on the severity of the regression.

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Case information

rID: 73109
Published: 27th Dec 2019
Last edited: 29th Dec 2019
Inclusion in quiz mode: Included

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