If you have any concerns, you could just make sure to clip their nails too. Our girls have nails that grow faster than weeds and get like spears (even with lots of walks and a huge yard with dog door). I've even filed them smooth and round after trimming once, when Hazel had a wound that needed some protection from that back foot scratching. But, in the end, the raft is really for the dogs!
Hazel rides the gear pile, Lila prefers the front.