As we found out over the weekend, Josh Johnson was placed on the 15-day DL with right shoulder inflammation. The first apparent sign was that Johnson’s velocity dropped to 91 mph in his previous start. He then felt discomfort during a bullpen session between starts, prompting the Fish to cautiously put him on the disabled list. Obviously Johnson’s stint on the DL is unrelated to his being pelted by a line drive in his right arm in that previous start against the New York Mets.
Johnson is hopeful that the damage is not too bad and that he can return in the minimum requisite two starts missed, but you can never be certain about any sort of injury to the shoulder. As Corey Dawkins and Ben Lindbergh pointed out in this latest edition of Baseball Prospectus’s Collateral Damage series (an injury article series that is almost worth the full BP subscription on its own), shoulder injuries, especially repetitive ones, can be very dangerous.
While it’s technically true that Johnson’s shoulder never forced him to the disabled list, he did miss almost a month at the end of the 2010 season with shoulder inflammation and a mid-back strain, and in 2009, he had a mild case of shoulder discomfort. Every pitcher experiences discomfort at some point, so we’re not going to crucify his shoulder for that, but the last two instances of shoulder problems have caused him to miss at least 15 days each.
With each bout of recurrent inflammation, the odds of an underlying injury—such as a rotator cuff or labral tear—increase. Hopefully this latest bout of inflammation is nothing, but we’re not quite sure we like Johnson’s chances.
It is certainly imaginable that repetitive motion of the shoulder, the sort of thing you would often see in a baseball pitcher, could cause shoulder inflammation. There’s a good chance this inflammation is actually subacromial bursitis, an inflammation of the bursa between one of the rotator cuff muscles of the shoulder and the above ligaments that structurally support the shoulder and clavicle. Over time, this motion can irritate and cause neurological symptoms in the arm and shoulder, including numbness, weakness, stiffness, or pain.
Bursitis itself is a manageable condition, but the problem causing the bursitis itself could be worse. Bursitis could be caused by damage to the surrouding structures, particularly tendons in contact with the bursa. That damage could lead to a rotator cuff tear, which would certainly be a more severe injury. If indeed there is a significant tear in one of the rotator cuff muscle tendons, surgical and non-surgical options are available for treatment, with lengths of recovery depending on the degree of shoulder damage.
Seeing as though this is not the first time Johnson has complained of shoulder stiffness or discomfort, you have to imagine that he may be having some difficulty with these issues. A comparative time table for a severe case of recovery from a shoulder injury would be Anibal Sanchez, who took just about two and a half seasons to fully recover from his torn labrum in 2007. Of course, Johnson could have a better outcome than this, and this injury could very well be nothing, but I do believe it is cause for alarm.