Editor's Note: Dr. Geier is director of MUSC sports medicine and an orthopaedic surgeon. He writes a sports medicine column for The Post and Courier.

For Clemson fans, the news brought the second sigh of relief of the day.

Shortly after Chandler Catanzaro made a 43-yard field goal as time expired to cap a comeback win over Wake Forest, Clemson coach Dabo Swinney told reporters that Sammy Watkins had a sprain of his AC joint and that his status against N.C. State was uncertain.

Midway through the third quarter, the freshman wide receiver was injured on a kickoff return. The team's medical staff examined Watkins' shoulder and ribs on the sideline before taking him to the locker room.

If the reports of his injury are true, the injury, diagnosis, and treatment are fairly straightforward. The acromio-clavicular joint, or AC joint, is the small joint on top of the shoulder between the tip of the shoulder blade (acromion) and the end of the collarbone (clavicle). It's the joint typically injured in a shoulder separation. These injuries typically occur when a player lands directly on his shoulder or is hit directly on his shoulder.

Usually with AC separations, a doctor can make the diagnosis by physical exam. If the injury is severe and there is vertical separation between the bones at this joint, one can see a bony prominence there. If there isn't a noticeable bump but the athlete has pain when the doctor presses directly at this joint, or when he positions the player's arm across his body, he likely diagnoses a mild AC separation.

X-rays are appropriate for these injuries to help make the diagnosis and determine the severity but also to rule out other injuries, such as clavicle fractures. Death Valley, like most stadiums, has X-ray capability for exactly this type of situation. The X-rays being negative suggests that this is a mild AC separation, where the ligaments stabilizing the joint are sprained instead of ruptured. The lack of vertical separation on X-ray suggests that the ligaments are not torn.

Swinney noted that Watkins won't need an MRI. Again, if the X-rays showed no displacement vertically between the end of the clavicle and the acromion, it is likely that most of the ligaments stabilizing the joint are intact. An MRI wouldn't change the treatment plan.

The problem with AC separations, even mild ones, is that they hurt. Often the pain at that joint makes lifting and using the arm painful. And it can be difficult to predict how long it will be until that pain subsides. Clemson athletic trainers and possibly physical therapists will work diligently to decrease his pain with ice, electrical stimulation, and ultrasound, and work to restore his muscle strength. As his pain decreases and strength improves, they will allow him to try to practice. They might try to pad that area for upcoming games, although if the injury hasn't fully healed, a direct blow there can still cause a good deal of pain. The team will wait and see if this process will take 3 or 4 days or 3 or 4 weeks.

I'm guessing by these reports that his recovery should be a quick one, but I would not be surprised if Swinney and the medical staff hold him out against N.C. State for precautionary reasons if he isn't 100 percent.

For more information about shoulder injuries and other sports medicine topics, please go to Dr. Geier's blog at drdavidgeier.com.