- Cauda equina
- A bundle of spinal nerve roots, called the cauda equina because it resembles a horse's tail, that arise from the end of the spinal cord. The cauda equina comprises the roots of all the spinal nerves below the first lumbar (L1) vertebra in the lower back. Impairment of the nerves in the cauda equina causes the cauda equina syndrome. It is characterized by dull pain in the lower back and upper buttocks and lack of feeling (analgesia) in the buttocks, genitalia, and thigh together with disturbances of bowel and bladder function.
* * *cauda equi·na -ek-'wē-nə, -ē-'kwī-nə n, pl caudae equi·nae -ek-'wē-.nī, -ē-'kwī-.nē the roots of the upper sacral nerves that extend beyond the termination of the spinal cord at the first lumbar vertebra in the form of a bundle of filaments within the vertebral canal resembling a horse's tail
* * *[TA] the collection of spinal roots that descend from the lower part of the spinal cord and are located within the lumbar cistern of the caudal dural sac; their appearance resembles the tail of a horse.
Cauda equina, descending from the conus medullaris of the spinal cord.
Medical dictionary. 2011.