Male, 4 months old, with caudal regression, imperforate anus, evaluate for tethered cord. Five normally formed lumbar vertebral bodies are demonstrated. Five sacral vertebral bodies are also seen. The posterior elements of the lower sacral segments are not well visualized. No coccygeal segments are identified.Spinal alignment is anatomic. Vertebral body height and morphology are otherwise unremarkable. No evidence of marrow signal abnormality is seen. No significant compromise of the spinal canal or neural foramen is identified.The conus may be slightly more rounded than what is typically seen, but it terminates at the L1 level which is within normal limits. The nerve roots of the cauda equina are unremarkable. No evidence of fatty filum terminale or any intraspinal mass lesion is seen. Clear anterior translation of the conus and cauda equina is demonstrated on prone imaging.
1.Although the conus appears slightly more rounded than what is typically seen, it terminates at a normal spinal level. There is no evidence of tethered cord on this examination.2.Poor visualization of the sacral posterior elements does not necessarily indicate a segmentation anomaly and may simply reflect thin or incompletely ossified bones.3.Lack of visualization of the coccygeal segments could reflect a very mild form of caudal regression.