I think there's a more important factor for the players than what is described in the article. It is how often does a player go out and do something that makes their injury worse because of this?
The issue I'm thinking more of is the concussion question, although there can certainly be life altering problems from other injuries.
I don't want to side track the discussion onto a tangent, but consider the Ted Johnson situation. He's been pretty clear in his statements that he felt that there was pressure from the coaches to "suck it up" and play, when perhaps, in hindsight, it wasn't such a good idea.
Cromartie's comments in the article also seem to suggest that he felt some pressure to play hurt.
I don't necessarily blame the coaches for this situation, they have only 53 bodies to work with and if they don't use this guy, they have to find a replacement. Player A at 80% may still be a better answer than player B at 100%.
If the players association is truly interested in having players not play when a medical situation has a chance to effect the rest of the players life, then the decision has to be taken out of the players and coaches hands.
They have to set up some sort of independent medical evaluation process and set up rules on what types of injuries mean a player doesn't play, period.
The only way I can think of for this to be effective, is to have this independent group provide the team medical staff, and ensure that this staff has full access to all players for whatever evaluation they want to perform.
For the owners to go along with this, I think you would need to set up something similar to the 15 day, 30 day, and 60 day disabled list in baseball. The durations would probably be different. In addition, there would have to be some adjustment in how the salary cap works relative to players on these disabled lists.