According to, NFL insider Adam Schefter has been told by a league source that the injury suffered by Detroit Lions’ quarterback Matthew Stafford has been diagnosed as a grade II shoulder separation. Stafford was injured yesterday in a game against the Chicago Bears. He was injured while being sacked by the Bears’ defensive star Julius Peppers. He missed the rest of the game and was seen with his arm in a sling.

An acromioclavicular joint injury, which is commonly known as a shoulder separation, involves an injury to the ligaments between the acromion (the tip of the shoulder blade) and the end of the clavicle (collarbone). There are six grades of AC separations. If this report is correct, then Stafford’s grade II separation means that there is some mild vertical separation between the ends of the bones. There is not a complete tear of all of the ligaments around this joint, such that the end of the clavicle would be vertically separated 100% or more from the acromion.

According to Schefter’s report, the former Georgia quarterback will see orthopaedic surgeon Dr. James Andrews in the coming days to get a better sense of the time he will miss. Again, I am not involved in Stafford’s care, but I can provide some insight on the expected treatment if, in fact, Stafford does have a grade II AC separation. Typically this degree of AC joint injury is considered mild in severity, although by no means does that imply it is not a painful injury. Typically grade II separations do not require surgical treatment. The length of time a player with a grade II AC separation is expected to miss is variable, as it depends on several factors. Most importantly, the pain has to decrease to a level that the player can resume his sports activities. After the pain and swelling have subsided, the athlete will work to regain shoulder range of motion and strengthening. Normally this process can take anywhere from 2 to 4 weeks. In Stafford’s case, this may be difficult, as the injury reportedly involves his throwing shoulder. As such, it might take him even longer to regain full strength, range of motion, and full throwing mechanics to allow him to play at an NFL-caliber level.

Please see the sports injury locator for more information about acromioclavicular joint injuries.

As always, please see my media section for my disclaimer regarding injuries among famous athletes.