Unfortunately, these type of knee injuries will continue to happen, due to the lost art of tackling. For years, players were drilled every day in the art of tackling correctly. Unfortunately, the art of the big hit, and getting yourself in the top 10 plays on ESPN has taken precedence over proper tackling. Now with high hits being outlawed, players feel they can only go low to take down bigger opponents, the fact of which couldn't be further from the truth (there is a lot of room to make a textbook tackle, from the lower chest all theway to above the knee). Hell, Rugby players know how to tackle better than NFL players. It's a shame, but this kind of injury will continue to happen.