We all know that animals, especially, can often overcome a weakness by strengthening another aspect of their body or senses to compensate.
One of my grandson’s and his wife adopted a beautiful part Maine coon male after he had many surgeries to save what was left of his two front legs. When they found him his front paws had been severed. He’s fine today, as you can see in the picture. He has learned how to get around, leap up onto furniture and play almost like any other cat.
Just like people, some cats are born with 
abnormalities. Injuries and neglect can cause physical damage. Here’s a site features some well-loved and adored cats with handicaps such as deformed limbs, Dwarfism, deafness and blindness as well as neurological issues. Have you ever treasured and pampered a cat with what might be considered a defect?
I loved a cat with what was probably a behavioral problem for his entire 17 years and it wasn’t always easy. Max was a wonderful cat. He was happy and he made me happy, but he constantly urinated outside the litterbox. Yes, we followed the entire realm of possible remedies, but he never changed his ways. I had to change mine. We pulled up most of the carpet in the house. I put down newspapers and pee pads for him. And I continued to love and care for him.
When his time came to cross the rainbow bridge we pulled up all the rest of the carpeting. I miss Max to this day, but not his bad habit.
Here’s a site featuring several special needs cats with injuries and birth defects they’ve had to learn to live with. https://cattime.com/cat-facts/advocacy/22571-8-special-needs-cats-that-have-the-internet-falling-in-love-with-them
