As was demonstrated by Kevin Ware's injury on a routine basketball play vs. Duke in the Elite Eight of the NCAA men's basketball tournament, crazy things happen.
Injuries are part of all sports, at every level.
Football is a violent sport, filled with collisions, bodies being twisted and all kinds of high-speed action.
There are going to be injuries, no matter the precautions taken.
So while in the case of Florida, who are suffering from several key injuries, changing the spring game into a practice is effective, avoiding injury is impossible.
A running back might catch his toe in the grass while making a cut, and blow out his knee.
A quarterback throwing a pass could hit a defensive lineman's helmet while throwing the ball, resulting in a broken hand.
Stuff happens, even in spring practice—just ask Knile Davis, who missed all of 2011 due to an injury suffered in spring practice.
Injuries are part of the game, and changing practice around to protect players more than the usual effective precautions is not going to change that.