the guy broke his shin because there is no rotation in his kick, see how he doesn't pivot his left foot or rotate his hips or shoulders at all, if you throw a powerful kick like that really hard and hit somebody's knee you're shin is going to break, your son should be fine as long as he learns to kick right
the thai kick is a power kick lifting your leg is not the proper defence it is better than taking it on the leg ,but you have to also turn your knee out to catch the guys shin on your knee cap very painful for the kicker have seen legs get broke
Actually you are supose to make shin to shin contact when your blocking a leg kick. It might hurt you, but it will hurt the person throwing it more, and he probably wont be too keen on throwing more leg kicks after that.
I am in love with this instructional and this woman too. Be sure to see her website at: http://www.mellei.com/
Also her father's website at: http://www.h2hctc.com/home.htm There are some pictures of her kicking in there that are pretty spectacular. Her father was in Army Special Forces.
Sorry for the distracting woman, but she is so perfect.
Nah the guy did the kick right the only problem was that thai fighters unconditionaly train their legs so round kicks dont hurt so a raised knee+a baseball bat results in a break. A round kick in thai boxing is designed to be similar to a baseball bat and since they train their legs to be able to resists those kicks when the white guy threw the kick instead of hitting muscle he hit bone