Open windows are a favorite hangout spot for my two cats, who love soaking in the sun and breeze and smelling all of the wonderful smells that only they can pick up. They aren’t alone—it seems all cats love window sills, and that’s why open windows are a particular concern.
It only takes one insecure screen to send a cat plummeting towards the ground, and these injuries happen so often that there’s actually a medical name for it—high rise syndrome. High rise syndrome refers to the injuries sustained when a cat (or, more rarely, a dog) falls or jumps from a height of two stories or more.
Not surprisingly, the number of injuries sustained increases as the fall increases in height from two stories to seven stories. BUT, the number of injuries actually decreases above seven stories because cats have the time to turn their bodies around in order to land feet first.
Let’s get into the physics of a fall that is over seven stories high. (If just the word ‘physics’ makes you break out into a cold sweat, fear not—I’ll keep it simple for both of our sakes.) Falling objects have a terminal velocity, or a point when the speed at which they are falling has reached as fast as it can. Terminal velocity is reached when the air resistance (or drag) of the falling object becomes equal to its weight. In humans, this is about 120mph. In cats, it’s closer to 60 mph, or about 5 stories tall.
Before a cat reaches terminal velocity, its vestibular system (the part of the body responsible for balance) senses that the cat’s speed towards the ground is still accelerating, and it tells the body to tense up and extend the limbs. Once terminal velocity is reached, the vestibular system can tell that acceleration has stopped, and the limbs relax. This allows muscles and tendons to absorb some of the impact.
The extent of injuries will vary, of course. Variables include the cat’s weight and age, the surface onto which they fall, and whether or not objects interfere with them in their fall. While objects such as fire escapes or vents may slow a cat’s fall, they may also disorient them, making sticking that landing a bit more difficult.
The most common injuries in feline high rise syndrome are injuries to the chest, including lung bruising and pneumothorax. Facial injuries, such as abrasions and jaw or tooth fractures are second most common, followed by fractured limbs.
All in all, though, cats fare pretty well, especially when they fall from heights over seven stories. Our canine companions aren’t so lucky. While they don’t typically lounge in the window sill, they do sometimes chase the errant toy out of the window. Without their feline cousin’s contortionist’s ability to right themselves, they are more likely to suffer severe injury.
While you’re enjoying that nice summer breeze blowing through your home, take a minute to make sure all of your window screens are secure, so everyone can safely enjoy this most wonderful time of year!