Tethered spinal cord

FACTS

  • At birth: the conus typically ends around the L3 vertebral level.
  • By ~2 months of age: it ascends rapidly, usually reaching the L2 level.
  • By adulthood: the conus typically lies at the L1–L2 intervertebral disc or the lower border of L1 (though anywhere from mid-T12 to upper L3 can still be considered normal).

HPI

universal ROS
  • urgency
  • incontinence

PHYSICAL EXAM

IMAGING

Spinal cord ultrasound
  • in newborns, a spinal ultrasound can raise suspicion for tethered cord if the conus and cauda equina rootlets do not freely move with respiration.
A/P
Counsel:
  • urinary dysfunction improves in > 50% of patients, but not guaranteed
 
 
Figure 1: Term infant with gross motor delay and a lumbar hemangioma found to have a conus ending at L3-4 with a large lipoomyelomeningocele. Laminectomies at L3 and partially at L2 were performed to identify the lipoomatous mass, which was resected with sonopet after ruling out neural tissue with stimulation at 0.4-1.0 mA. Subsequently, circumferential dissection was undertaken to identify superior and inferior margins of lipoma safely. Intraoperatively, two points of fatty tethering to spinal cord were identified.
Figure 1: Term infant with gross motor delay and a lumbar hemangioma found to have a conus ending at L3-4 with a large lipoomyelomeningocele. Laminectomies at L3 and partially at L2 were performed to identify the lipoomatous mass, which was resected with sonopet after ruling out neural tissue with stimulation at 0.4-1.0 mA. Subsequently, circumferential dissection was undertaken to identify superior and inferior margins of lipoma safely. Intraoperatively, two points of fatty tethering to spinal cord were identified.