The Twins have moved 2013 first round pick Kohl Stewart to the disabled list with a right shoulder impingement. A shoulder impingement is a "common cause of shoulder pain" caused by bones in the shoulder. Here's more from WebMD:
[Shoulder impingement] occurs when there is impingement of tendons or bursa in the shoulder from bones of the shoulder. Overhead activity of the shoulder, especially repeated activity, is a risk factor for shoulder impingement syndrome. Examples include: painting, lifting, swimming, tennis, and other overhead sports. Other risk factors include bone and joint abnormalities.
With impingement syndrome, pain is persistent and affects everyday activities. Motions such as reaching up behind the back or reaching up overhead to put on a coat or blouse, for example, may cause pain.
Continued use of the shoulder could have resulted in a rotator cuff tear, with some experiencing a ruptured bicep as a secondary issue. As a pitcher, if you're having trouble working overhand, it could be a sign of a serious issue. It's unclear how serious of an issue this is for Stewart, but stopping Stewart from pitching is obviously the right thing to do.
Treatment of a shoulder impingement is typically rest and rehabilitation, combined with anti-inflammatory medication. The medication cycle "is six to eight weeks since it often takes that long to fully treat the problem." If a player does not respond to one type of anti-inflammatory, the doctor will try different one until he or she finds one that works. Stretching, avoiding lifting the elbow above shoulder height, and warm showers are recommended as part of a rehabilitation program, and it's common for some work with a physiotherapist as well.
If the issue persists, doctors may use a "cortisone-type injection." Should that not do the trick, doctors will perform other tests to rule out a tear of the rotator cuff. WebMD finishes by saying:
The vast majority of people who have impingement syndrome are successfully treated with medication, stretching exercises, and temporary avoidance of repetitive overhead activity until the condition settles down.
Stewart was probably pitching through some pain recently, but hopefully not for too long. If the diagnosis of a shoulder impingement matches the recommended course of action from WebMD, because of the timing of the injury and the time of year it is for Cedar Rapids it's unlikely that Stewart will return to action before fall or winter leagues start up. His season in Single-A saw him make 17 starts with 81.2 innings pitched, while allowing just 69 hits, striking out 58 and walking 23. He gave up just three home runs.
Considering Stewart will be just 20 in October, I imagine it would take a very strong performance from him over the winter to keep him from at least starting the 2015 season at Single-A again. Of course, with his talent and mentality, and considering Jose Berrios was in Advanced-A at age 20, you never know - Stewart could force the Twins' hands.
For now, let's just hope it's just a shoulder impingement. He'd be a fun one to watch in the off-season.