Attribute adjustments for catastrophic injuries
 

So I'm playing my franchise. I'm playing against the Falcons, and Mark Anderson comes off the right end and sacks Matt Ryan. (Yay) Matt Ryan doesn't get up. He's carted off, and I finish the game. After the game I check my e-mail like I always do, and I find out Ryan tore his MCL and was placed on IR. As I was checking my stats and standings and such it hit me. Injuries like that usually don't just shut a player down for a season, but they have lingering effects for sometimes the rest of his career. Kevin Jones and Tommie Harris are two such examples on my own favorite team. In the example of Ryan's injury on the game, I figure it would affect his Speed and Scramble attributes for sure, and possibly his Aggressiveness and Composure as well (he wouldn't want it to happen again.) Things like concussions would affect a player's Awareness and Durability (one concussion greatly increases the risk of another). Something severe like a spinal injury could potentially effect everything. I'm basically fishing for opinions here as to how much I should drop a player's attributes for each type of injury. Sorry for being so long-winded and thanks in advance for any response.