High-rise syndrome


High-rise syndrome is a veterinary term for injuries sustained by a cat falling from a building, typically higher than two stories.

Injuries sustained by cats falling

Common injuries sustained in cats after a fall include:
Studies done of cats that have fallen from 2 to 32 stories, and are still alive when brought to a veterinarian clinic, show that the overall survival rate is 90 percent of those treated.
In a study performed in 1987 it was reported that cats who fall from less than six stories, and are still alive, have greater injuries than cats who fall from higher than six stories. It has been proposed that this might happen because cats reach terminal velocity after righting themselves at about five stories, and after this point they are no longer accelerating, which causes them to relax, leading to less severe injuries than in cats who have fallen from less than six stories. Another possible explanation for this phenomenon is that cats who die in falls are less likely to be brought to a veterinarian than injured cats, and thus many of the cats killed in falls from higher buildings are not reported in studies of the subject.
In a more recent study, it was observed that cats falling from higher places suffered more severe injuries than those experiencing shorter drops.

Righting

During a fall from a high place, a cat can reflexively twist its body and right itself using its acute sense of balance and its flexibility. This is known as the cat's "righting reflex". The minimum height required for this to occur in most cats would be around.
However, it has been argued that, after having reached terminal velocity, cats would orient their limbs horizontally such that their body hits the ground first.
A 1987 study speculated that this is done after falling five stories to ensure the cat reaches a terminal velocity by thereafter relaxing and spreading their bodies to increase drag.

Why cats fall from high places

Cats have a natural fondness for heights. If a cat is distracted by potential prey, or if it falls asleep, it can fall. If this were to occur in a tree, for example, the cat would often be able to save itself by grabbing on with its claws. Many building materials such as concrete and painted metal do not allow a cat to grip successfully.