-Rule changes. With the NFL focusing more on hits to the head many rules have been changed to protect defenseless players and fines for the defender. While 3-5 of these injuries can be attributed to defenders going low during the tackle it seems that the rule change is not to blame for the increased number of injuries. Most of the incidents were non-contact.
- Grass Vs. Turf. All but 6 of the ACL injuries have occurred on grass fields this year. This may be due to players changing their shoes to give them more speed rather than full leg support. This may cause them to slip slightly on grass fields causing their knees to buckle.
- Lack of an offseason training program. With the new collective bargaining agreement there is a limit on how much a player can do to get in shape for the upcoming season. Most of these players are just like everybody else, if they don't have to do anything then they aren't going to do anything. Being unprepared for a grueling NFL season and improper conditioning may be a major cause in all of these injuries. If conditioning truly is the case we should see a drop off in knee injuries throughout the season.
Whatever the reason is for these ACL injuries it is imperative for these players and teams to take the utmost care with them. Far to often players are pushed to rush back just like Robert Griffin III. Not everyone is Adrian Peterson and we cannot expect players to be the same person after these types of injuries If they come back at all.