Bladder Function Following a Spinal Cord Injury


Function of the Urinary System After a Spinal Cord Injury

Following a spinal cord injury certain parts of the urinary system process are affected by damage to the spinal cord.

The kidneys will continue to filter urine from the blood, and the ureters will continue to push the urine into the bladder for storage until urination takes place. The kidneys and ureters still work, because they are involuntary processes and do not require signals passed from the brain via the spinal cord.

The main process of the urinary system which is affected following a spinal cord injury is that of emptying the bladder on a voluntary basis in a process called urination. Urination in a voluntary context requires messages to be sent to and from the brain via the spinal cord. When approximately 250 to 300cc of urine are in the bladder, messages from stretch receptors in the bladder are sent through nerves which enter the spinal cord near it's end in the sacral level of the spine. If the spinal cord is damaged, the action of coordinating the relaxation of the sphincter muscle and contracting the detrusor muscle may be affected, resulting in an inability to urinate properly. In addition to not being able to urinate, the sense of a full bladder may also be lost, as sensory signals from the bladder will not be able to travel to the brain through the damaged spinal cord.

The manner in which the bladder works following a spinal cord injury will depend on the level of injury to the spinal cord. Different levels of injury will affect different nerves which allow the bladder to function, and this will be a deciding factor in choosing the right bladder management program.

  • Bladder Spinal Nerves