Cauda equina syndrome is a condition caused by damage to the bundle of peripheral nerves protruding from the bottom of the spinal cord, called the cauda equina.
The latin words cauda equina mean horse’s tail, which is what early anatomists thought this nerve bundle looked like.
The spinal column is made of individual bones, called vertebrae.
Each vertebra is made of a large anterior portion called the body, and the posterior part called the vertebral arch.
The central cavity between the body and the arch is called the vertebral foramen.
Now the spinal column is made of 33 vertebrae: 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 4 coccygeal.
Other than C1 and C2, each two adjacent vertebrae are, separated by an intervertebral disc, which allows for a slight movement of the vertebrae, and acts as a shock absorber.
The sacral and coccygeal vertebrae are fused together to form the sacral bone and coccyx, or tailbone respectively.
Now if you cut the spinal column in half lengthwise you can see that all the vertebral foramina together form the vertebral, or the spinal canal, which is occupied by the spinal cord.
The spinal cord is connected to the brain and travels through the spinal canal to the second lumbar vertebra, where it ends in a cone, called conus medullaris.