That is very odd! This sounds like something genetic. However, I am assuming this is his first nail cut?? You had said you had him for a year 1/2 but you only noticed it today. Let me know if I am getting that mixed up somehow. So if that is the case, it could be possible that his nails got too long and broke at some point??? I am not saying this to make you feel bad, it's just that normally you would want to check his nails every 4 - 6 weeks and trim as needed. (however, the fact that they are ALL this way makes me lean towards genetic issue). Do the nail stubs look reddish or dark?
I could see how his foot position may be affected if the nails to do offer support.
This is very a interesting case -- so when you do bring your bunny to the vet, please be sure to update this thread. Whether it's genetic or not, it would just be educational and helpful for everyone.