Adding onto this,
Limb Loss - Enough hits with a melee weapon will make you lose limbs, losing your right arm will make you be unable to use weapons.
Footshot - shooting someone's foot can slow them down. Shooting both will autocrouch them.
Blood Loss - Being at 10 or lower health will make you bleed out. Bleeding out will last for atleast until you die or get healed. Bleedout victoms have a chance to die from stroke 5 seconds after being healed, 3% chance.
Cut\Laceration - Functionally similar to blood loss but no stroke chance and can only be inflicted by melee weapons. Can get infected, activates at 50% or lower and has a random time between 2 seconds and 10. 2 HP lost a second.