regarding 2010, Sue Dinem at NationalsProspects.com offered this:
http://nationalsprospects.com/2011/07/thursdays-news-notes-13/The injury was in his shoulder, that much I can confirm, per Byron Kerr and John Sickels. Whether or not he had surgery, I cannot.
Nearly every scouting report around his 2009 drafting referenced his poor mechanics. He’s been in XST and in the GCL for months now, so you have to think his mehanics have been “fixed.” Plus, if he’s been strong enough to go 4-5IP on six days’ rest, he might be ready for Auburn on his next turn (~7/19)