the world and the science still wouldn't support you making a blanket statement the way you did as a fact claim. Yes maybe and maybe is all you get. If you had said there is a risk with the level at which that child is performing those exercises... but you didn't. I am exercising faith that you are being honest about your background and that you are competent at your profession. So this isn't an indictment on your ability to observe risk as a medical professional. Is it possible you were being a bit laissez faire with the facts?
That father may actually not be setting his child up for those injuries at all. You would have to not only examine the child, get family history, but even work with geneticists to even get a pathology or risk assessment which even then would given you some form of percentage of possibility.