Accepted dogma has it that a zombie has to be shot in the head to be permanently killed.
In the Sandman Slim series, a zombie hunter says the only way to kill one is to rip the spine out.
I suppose other accepted methods include complete burning, (but what about the smoke? Is it a contagion?), a nuke which shreds the zombie into subatomic particles, immersion in acid and other forms of total destruction.
But what about less critical damage.
Say you shoot both arms off at the elbow and both legs off at the knee? Go for the shoulder and hip, then. Or maybe you go full Conan the Barbarian and cut it in half.
At what point do you do enough critical damage to end the zombie without affecting the brain? If the central nervous system is what matters, imagine this: An intact head and intact spine. Nothing else. Torso and legs ripped away. Is that enough?
Inquiring minds and all that.