What actually kills a person whose neck is broken?
This was a very interesting question. To be sure that we explained this correctly, I asked Doug P. Lyle, MD of The Writers Medical and Forensics Lab to explain it to us. Here is my revised question and his answer:
Could you tell me what actually kills a person when they break their neck? Obviously not everyone with a broken neck dies, so what is the deciding factor. Is it basically suffocation due to the inability to breathe from the immobilization of the nervous system, or is it actually more immediate?
You are correct that not every broken neck leads to death.
Christopher Reeves survived his but of course suffered quadriplegia as a result of his injuries. The cervical vertebrae (neck bones) are the top 8 bones in the spinal column. As such, they are part of our backbone and they also serve to protect the spinal cord from injury. If the vertebrae are broken, but the spinal cord is unharmed, then no neurological problems result. Of course these people are treated very carefully while the bones heal to avoid in post-injury damage to the cord.
If the cord is bruised or partially damage, then quadriplegia or other neurological problems may occur. If the cord is severely injured and this injury is at or above the fifth cervical vertebra (C5), then breathing may be effected and the person may die from asphyxiation. The portion of the cord that controls breathing is about C3 through C5. If the damage is below C6, then paralysis may occur, but breathing would be left intact.
However, if the cord is severely injured or transected (cut or
torn in half), there is sudden loss of nerve supply to the entire body, including the heart and blood vessels. The victim may suffer a sudden and profound drop in blood pressure (BP), which can lead to a very sudden demise. Often, immediate. This is called spinal shock.
So, your victim could be completely okay, except for a cervical fracture, or could be partially paralyzed, or could be rendered quadriplegic, or could die over 2 to 4 minutes from asphyxia, or could die almost instantaneously from spinal shock.
Our thanks to Dr. Lyle for his great explanation. Be sure to take a look at other explanations on his site at: The Writers Medical and Forensics Lab
For additional reading on spinal injuries visit:
What Happens In Human Spinal Cord Injuries?