Why a head or spinal injury considered more severed than an injury to other parts of body?

Head mainly brain and spinal cord control all activities very crucial to body

The spinal cord carries out two main functions: It connects a large part of the peripheral nervous system to the brain. Information (nerve impulses) reaching the spinal cord through sensory neurons are transmitted up into the brain.

And when the spinal cord is damaged, the highway is essentially closed. Nerve impulses can't get through. This results in paralysis – loss of mobility and sensation – below the level of injury.

If these area are affected by injury it will lead to even immediate death also when breathing is stop

That's why

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