Spinal cracker 

A spinal cracker is a hand to hand fighting technique, in which a target is choked from behind and a knee is rammed into their spine.

The Commandos learned the spinal cracker technique to attack sentries.

Spinal cracker by I, Wreckerrr October 4, 2016

Spinal clacker

Slamming a person to the ground and applying trauma to the spine.

I was in a bar fight and slammed the bouncer to the concrete and caused a spinal clacker.

Spinal clacker by Whisker Biscuits December 19, 2019