I'd have to agree with Theresa, just get them a scratching post, especially if the cat lives with other animals or goes outside. A cats claws are its main line of defense, you might know it doesn't have claws but the cat might not fully realize it all until it's too late. It'd be like me giving you a gun and saying "If you ever need to protect yourself just use this and everything will be ok"....BUT I'd take the bullets out.

If a cat gets scared it'll try to use its claws, if another animal realizes that the cats' claws are gone then you can say goodbye to your cat too.

pain of loss of cat > cost of a scratching post