Football Outsiders has a metric called "Adjusted Games Lost" (AGL). I have a difficult time figuring out why such a statistic would not correspond to the amount of losses teams had (i.e. the AGL numbers are in the tens to hundreds range), but here is their explanation of what it means:
To refresh memories, the key ideas underlying AGL are that all players don't affect winning and losing equally, and missing a game isn't the only way a player injury affects winning and losing. Injuries to starters, important situational reserves (e.g., nickel cornerbacks), and injury replacements (i.e., new permanent starters) count towards AGL, whereas injuries to benchwarmers don't. Similarly, injuries that land a player on injured reserve affect AGL more than injuries that force a player to be listed as "questionable," which in turn affect AGL more than injuries that lead to a "probable" game status.
In 2011, the Browns had an AGL of 71.8, which ranks them as the 10th most injured team in the league. That is an improvement from the 2010 season, when they were ranked as the most injured team in the league. You can assume that injuries to Peyton Hillis and T.J. Ward probably had the most significant impact on the team's ranking. Other injuries that might have been played a factor include Joshua Cribbs, Mohamed Massaquoi, Colt McCoy, Montario Hardesty, Scott Fujita, and Tony Pashos.