
Our Springer had one dew claw, it looked weird, but it never bothered her, until one day she went through some gorse, she got a piece of twig caught on it, and it really made her yelp., from then on she always seemed to catch it and give a little yelp.
The vet charged us £10.00 to remove it while she was being speyed, and it caused no problems being removed, and we haven't heard a little yelp since.
My advice would be if its not causing problems then leave it well alone, IMHO :)
Robert