And unlike prosthetic arms and hands, which many patients find frustrating, the ones for legs are good. That makes the risks of a transplant not worth taking.
"It's premature" until there are better ways to help nerves regrow, Lee said.
Now Marrocco, who was the first soldier to survive losing all four limbs in the Iraq War, is looking forward to getting behind the wheel of his black 2006 Dodge Charger and hand-cycling a marathon.
Asked if he could one day throw a football, Dr. Jaimie Shores said sure, but maybe not like Baltimore Ravens quarterback Joe Flacco.
"Thanks for having faith in me," Marrocco interjected, drawing laughter from the crowd.
His mother said Marrocco has always been "a tough cookie."
"He's not changed that, and he's just taken it and made it an art form," Michelle Marrocco said. "He's never going to stop. He's going to be that boy I knew was going to be a pain in my butt forever. And he's going to show people how to live their lives."
Associated Press Chief Medical Writer Marilynn Marchione in Milwaukee and AP writer David Dishneau in Hagerstown, Md., contributed to this report.
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