The Tigers wasted no time in diagnosing Doug Fister's injury that caused him to leave in the 4th inning of today's 10-0 win over the Boston Red Sox, determining that Fister would miss at least 15 days with a "costochondral strain." With the masses on Twitter having absolutely no idea what the hell costochondral means, I figured I'd put my six figure loan debt to good use and drop some knowledge on the rest of you. Get ready, this might be the most intelligent thing we've ever posted here at D4L.
The cartilage that connects the ribs to the sternum (or breastbone) is called costochondral cartilage. Because of what the rib cage protects, this cartilage need to be pretty solid, but it has a little give to it in order to allow for chest expansion during breathing.
A costochondral strain is when the rib separates too much from the sternum, and the cartilage stretches beyond its capacity. For example, if you've ever sprained your ankle and it feels a little unstable afterward, this is the same idea. Depending on the severity of the strain, it can cause pain in a number of areas, but usually along the chest wall and into the abdomen. Other than rest, there isn't much that can be done to treat this in the early stages.
In Fister's case, expect him to be back in a few weeks, as long as he doesn't have any setbacks. With how quickly his injury occurred (it seemed as if he hurt himself two pitches before he came out of the game), I don't think that this will be something that nags at him throughout the season.