In a Dec. 18, 2012 photo provided by Johns Hopkins Medical, a surgical team at Johns Hopkins Hospital in Baltimore works on a double arm transplant for U.S. Army infantryman Brendan Mar

 

              In a Dec. 18, 2012 photo provided by Johns Hopkins Medical, a surgical team at Johns Hopkins Hospital in Baltimore works on a double arm transplant for U.S. Army infantryman Brendan Mar
In a Dec. 18, 2012 photo provided by Johns Hopkins Medical, a surgical team at Johns Hopkins Hospital in Baltimore works on a double arm transplant for U.S. Army infantryman Brendan Marroco, 26, who lost all four limbs in Iraq. The transplants are only the seventh double-hand or double-arm transplant ever conducted in the United States. The infantryman was injured by a roadside bomb in 2009. (AP Photo/Johns Hopkins Medical)