I didn't cite any because - correct me if I'm wrong - the issue of how bad posture affects the human skeleton is a solved problem, i.e. it's basic common knowledge that can easily be found online or discussed with a medical doctor.

I don't think it's necessary to go all the way and research citations to disprove claims that are just challenging basic common sense without any argument in their support, e.g. I don't really go to great lengths to use data to disprove claims related to astrology.