EA is working on revamping how injuries work in Madden 2010. Their plans include:
1. Injury status / severity is delayed instead of immediate for more suspense and realism
2. All new animations with trainers and injury carts are shown
3. You are automatically prompted to let injured players play hurt (when applicable) or sub in the backup
4. Players playing hurt have their ratings negatively affected (based on the severity of the injury)
5. Players playing hurt have a (logical) risk of re-injury
6. Players show that they are hurt with in-game injury animations like limping
7. Re-injuries happen realistically instead of randomly.