The spinal cord contains motor neurons that control the muscles responsible for breathing, including the diaphragm (controlled by nerves at C3-C5), intercostal muscles (controlled by thoracic nerves), and abdominal muscles. When a spinal cord injury occurs at or above these levels, the signals from the brain to these breathing muscles are interrupted, resulting in partial or complete respiratory paralysis. Injuries at C1-C3 typically require immediate and permanent ventilator support, while injuries at C4-C5 may allow some diaphragm function but still cause significant breathing difficulties.
Respiratory complications are the leading cause of death in the acute phase following spinal cord injury and remain a primary cause of morbidity and mortality throughout the victim's lifetime. These complications include reduced vital capacity, ineffective cough, mucus retention, atelectasis (lung collapse), pneumonia, respiratory failure, and sleep-disordered breathing. The higher the level of injury, the more severe the respiratory impairment, with cervical injuries presenting the greatest risk.
From a legal perspective, establishing the full extent of respiratory complications requires comprehensive medical documentation, including pulmonary function tests, arterial blood gas analysis, sleep studies, chest imaging, and expert testimony from pulmonologists and respiratory therapists. This medical evidence is essential to demonstrate the severity of the injury and justify the substantial compensation needed for lifetime respiratory care and equipment.