well i'm not sure what mr. hayes background is to know what type of injury he has or what would affect it, but i can tell you that the shot he took to the quad would have affected the quad. lol.
The injury was present and brace was applied when he fell on that knee a game or two ago and was pushed down on the flexed knee. I don't remember exactly when that happened. That certainly could have made his situation worse at the PCL.
Kid needs rest, but a shot to the quad by a helmet is no joke. complicates things for good muscular contraction around an already injured knee. I don't think anyone is questioning that his knee is the primary injury, but a quad injury on the same side changes things significantly on that plant foot side.