The side kick to the knee/upper thigh..

I agree that joint locks are very dangerous, but you can't compare grappling to this particular strike.

They are called submission locks for a reason. There is a reason why fighters don't pull until they break a guys bones.. It's because his opponent submits. Sure a fighter can quit on his feet, but they seldom do. Grappling and striking have too many differences in rules of engagement that makes you're comparison mean nothing.

The side kick to the knee hasn't been thrown with vigor yet, once it is, it will instantly end a fight, causing a scene, and possibly career ending damage. Thank God these MMA haven't walked right up and side kicked someone in the knee/front of the leg with all their might. For whatever reason, I think that they know better. If they wanted to, a fighter could easily walk right up and kick you as hard or soft as they want in the frontal knee region all night. Sooner or later, even you two posters would start complaining.

When I have seen this side kick thrown, fighters aren't putting a whole lot of power behind it. Maybe that is the way it is supposed to be executed, but don't think that it couldn't seriously damage their opponent. Hell athletes blow out their ACL/MCLs by just doing drills and running.. QBs hyperextend their knees and far worse with what looks like the slighest touch.

This strike is one that has flown under the radar for quite some time in MMA.. Most don't notice or really care until a serious injury occurs.