When Spc. Bryan Wagner is driving, he pushes the gas pedal with his right foot in spite of the fact that he doesn't have a right foot. "I drive with it," the 23-year-old said, referring to the prosthetic limb that replaced the real one he lost in Baghdad on Dec. 17, 2007, when the Humvee he was a gunner on ran over an improvised explosive device. But Wagner, an Exeter, Calif. native with a military buzz and the burly build of an offensive lineman, says vehicular matters aren't high on his to-do list. Neither is running a marathon, which he has somehow done, and snowboarding, which he still enjoys. What dogs him is the "phantom pain" he feels in the limb he lost, a common complaint among amputees dating back to previous wars and even showing up in literature. In David Guterson's novel "Snow Falling on Cedars", about the Japanese-American experience during and after World War II, the protagonist Ishmael Chambers complains of pain from his missing left arm. As of July 1, a total of 904 service members have undergone amputations resulting from the wars in Iraq and Afghanistan. Therapy helps limbs "see" But a new technique called "mirror image therapy" is using the reflection of the intact limb to trick Wagner's brain-in a good way. Wearing black shorts and sweating though a tan cut-off T-shirt, Wagner demonstrated the technique Thursday at a physical therapy hub for wounded soldiers at Walter Reed Army Medical Center. Dr. Jack Tsao, a staff neurologist at Walter Reed, oversaw <b>...</b>