The amount of respiratory impairment following spinal cord injury depends on
the level of the lesion. Nerves coming from C3-5 supply the diaphragm, the major
muscle involved in breathing. If the injury is above C3 you cannot breathe on
your own and will need a mechanical respirator. C-spine and T-spine nerves supply
other muscles that help you to breathe. Any cervical or thoracic injury will,
therefore, decrease your ability to breathe and can lead to lung infections.