I think some players are more prone to injury (just like with fouls it's not shown in ratings) and a good doctor can lessen the length but not prevent. I had two starters injury (once at the same time last season). Overall last season I had three injuries with two to the same guy. This season I just had my first injury... to the same guy who had two injuries last season.
I'd be interested if anyone else has found a trend in players being injury prone.
No matter where you go, there you are.