Why do you become paralyzed after a spinal cord injury?

Spinal Cord Injury: When the spinal cord, the spine is damaged, severed, cut, or crushed, the softer tissues of the cord are damaged, often permanently. These nerves come from the brain, go the internal organs, the arms, legs, muscles, skin all over the body. Damage is permanent, the nerves will not work, and the brain cannot feel or control the muscles, which is the definition of paralysis.

Loss of function : The spinal cord provides a communication pathway between the brain and the rest of the body and it helps to modulate those 2 way communications. If injured , this communication can be affected leading to variable presentations including paralysis depending on what level is injured and to what extent.