The diagnosis is in for Vance Worley, on the DL with arm soreness. Worley has bone chips in his throwing arm, reports Matt Gelb of the Inquirer.
The bone chips look like this:
Okay, maybe not like that. But, the news is somewhat good as this is something people can pitch through, though with some soreness. Gelb's piece mentions that Cole Hamels had them last year and had to undergo surgery to remove them.
What are bone chips? Healthinformatics.net explains:
The bone or cartilage in the elbow joint may be injured. Cartilage is tough, smooth tissue that lines and cushions the surface of the joints. Chips usually come from the upper arm bone (humerus). The fragments of bone or cartilage come loose and float around in the elbow joint. This condition is also called osteochondritis dissecans of the elbow. The fragments may also be referred to as a joint mouse or loose bodies.
They are caused by "trauma" to the joint. I'll say pitching can do it. Treatment in the interim is ice and pain relievers.