Have you or do you have an animal that is handicaped? I have a cat that is deaf. I had a cat years ago that was blind in one eye. And several with medical problems.
I used to take care of a colony of cats and there was a female cat who was born with Cerebellar Hypoplasia. It's what a lot of people call a "wobbly cat" meaning they can't stand up straight, their heads shake, and they fall over a lot. Only time you'll see a wobbly cat not fall over is when they run like heck. It occurs when the part of the brain that controls fine motor skills (the cerebellum) is not completely mature at birth. Some of these cats can do OK getting around, they just fall over a lot and they "peck" at their food to eat because they can't keep their heads still long enough to get a mouthful. Others aren't so lucky and can't walk at all. It's a non-progressive disease, but there is no cure for it.
I never had to worry about her getting over the walls because she was born in my back yard and her Mama just never left, lol. They had it good because I sheltered all of them, fed and watered them, and most of all, I watched over them for the jerk bags that lived in my neighborhood who made it a habit to shoot at these cats with B-B guns and Pellet guns, and I'm not talking about kids but grown men who used to sit in their yards, get drunk, and take their pathetic lives out on these animals. I had most, if not all, of the females spayed and even had a few of the males neutered. I was able to place a lot of them with a rescue and they were eventually adopted out to worthy pet parents. "Cream Puff" was adopted by a young woman who already had experience with a cat with Cerebellar Hypoplasia, so that sweet girl found the perfect home.