Declawing, or onychectomy, is not just the removal of the claws, but amputation of the last bone in each of the ten front toes. The series of amputations can sometimes sever tendons, nerves, and muscles. In fact, many organizations, including The Humane Society of the United States, have issues formal statements opposing declawing cats.
If you do have a cat that is declawed, vets recommend using a soft liter that will not re-open any wounds. Because of the prolonged pain after surgery, many declawed cats tend to avoid the letter box altogether because their paws may hurt when scratching in the box.
There are alternatives to declawing your cat. When done properly, regular trimming of their nails (a vet can show the proper way) poses little risk to the cat.
Before domestication, cats used tree trunks to exercise, stretch and mark their territory. It is possible for cats to be trained to use a scratching post in order to fulfill their natural instinct to scratch.