Calling in a specialist to help with an unusual injury  Fifteen-
year-old Justin Villard lies on the exam table and nervously
crosses and uncrosses his legs. His long, brown eyelashes bounce
slowly up from his ruddy cheeks as he tells what happened. His
voice is matter-of-fact, even though what he's talking about
sounds horrible.  "I picked up the staple gun to move it and
accidentally pulled the trigger. The safety was off and the
staple went into my arm. I didn't feel it for the first 30
seconds, but everyone was looking at me, saying 'Oh my gosh!
You've got a staple in your hand.'"  This isn't just any staple,
but an industrial, two-inch-long staple used to penetrate wood.
Justin's mother, Joanne, looks on, barely able to glance at the
painful-looking injury. Justin was helping a friend repair a
roof when the accident happened. Now, the staple has punctured
his arm clear from one side to the other. Two thick, steel
points protrude about a quarter-inch from his bloody inner
wrist.   Kathy Wussow, MD, a pedia