Cauda Equina Syndrome (CES)
Cauda Equina Syndrome is also known as Pelvic Visceral Dysfunction, and is a rare but important back pain syndrome.
It requires emergency evaluation and surgery.
What Is The Cauda Equina?
In adults the spinal cord ends in a structure called the “conus medullaris”, a short cone-shaped area about 2.5 cm long. This tapers to the “filum terminale” where it ends. The end of the spinal cord is usually at the level of the first lumbar vertebra, much higher than people expect.
Lumbar & Sacral Nerves
The huge number of nerves travelling down in the spinal cord are inside the canal formed by the skeleton of the back. They have to get out of the canal and pass into the body to supply the muscles and skin of the trunk, arms and legs. At each “spinal level” (each disc) the nerves pass out through a gap formed by the vertebrae above and below. At that point they are referred to as nerve roots.
As more and more nerves pass out of the spinal cord it gets smaller and smaller, until eventually it is just a collection of thinner nerves which are left to exit into the body.
The lowest four sacral nerves emerge from the conus medullaris and the five lumbar ones emerge from the enlargement of the spinal cord above this and run downwards. These two major groups of nerves are then called the cauda equina (”horse’s tail”). This includes all the spinal nerve roots from the first lumbar downwards.
What is the function of these nerves?
The nerves in the cauda equina are the motor nerves (controlling movement) and sensory nerves (transmitting feelings) but also nerves which control the pelvic organs.
These systems, the sympathetic and parasympathetic nerve systems, have opposite effects but are both vital for the normal control of bowel, bladder and sexual function. Feedback transmitted along these nerves from the abdominal and genital organs is essential for these functions.