Tyler Southern awoke in his hospital bed at the Walter Reed National Military Medical Center in Bethesda, Md., and reality came flooding back. Both of his legs and his right arm were gone, blown off in Afghanistan two months earlier by an improvised explosive device so powerful that only bits of his legs and boots were ever found. The explosion left one remaining limb, his left arm, broken and mangled.
    A 22-year-old Marine Corps corporal, Southern is just one of a growing number of young Americans -- 16,000 or more, so far, out of 2.3 million American troops sent overseas -- who volunteered for Iraq or Afghanistan and came back alive but catastrophically wounded.
     In Iraq several years ago, an IED blast tore off both legs of a soldier and ripped open his...

...abdomen from sternum to pelvis. Trauma surgeons recorded a daunting list of other injuries: severe head injury, anoxic brain damage from lack of oxygen, spinal cord injury. Metal splinters and filth perforated his internal organs. His pelvis was shattered into more than 60 pieces. In a 24-hour period he lost 60 units of blood. He was 22 years old with a young, pregnant wife.  "It was one of the most gruesome things I've seen in medicine," said McNamee, at the VA Polytrauma Center in Richmond. Va. "He'd wake up every two or three hours and start shrieking, where are my fucking legs, who took my fucking legs?  "How do you fix a guy like that? You can't. There's so much loss, so much despair," he added. "It's a matter of resetting expectations, trying to pull the individual and the family back after such a catastrophe."     More Americans are being wounded in combat. And their wounds are more severe and complex, raising difficult issues for military medicine and for the nation on which disabled soldiers will depend for a lifetime of care. The number of American soldiers who lost at least one limb in combat doubled from 86 in 2009 to 187 last year, while the number with multiple limb loss tripled, from 23 in 2009 to 72 last year. Those in need of blood transfusions of 10 units of blood or more (the human body holds a total of 10 units of blood) rose during that 12-month period from 91 to 165.     And triple amputees like Tyler Southern are becoming more common. Their ranks have nearly doubled this year from the total of all triple amputees seen over the past eight years of war, the Army said in its report, "Dismounted Complex Blast Injury."