This happens often enough
see the full
http://www.cnn.com/2010/HEALTH/04/15/unexploded.shell.head.afghanistan/index.html?hpt=T2
"The projectile was part of the bomb that went off," explained Maj. John Bini, who oversees all trauma care at Bagram. "People will pack just about anything in to these things: rocks, nails, screws, explosives."
Bini and his team immediately summoned an explosive ordnance disposal team to assess how risky it would be to conduct the surgery. The doctors needed to minimize the risk of setting off the ordinance.
They were told not to drop the explosive, prick it with a scalpel or let it be exposed to any electricity.
"We knew that any electrical current possibly could cause detonation."
