May 1, 2007: The widespread use of roadside bombs and rocket propelled grenades in Iraq is causing more injuries than it appears. As early as 2004, when army doctors checked out soldiers wounded in Iraq, they found 62 percent also had undiagnosed concussion injuries. Later studies found that 18 percent of all troops serving in Iraq suffered some damage from roadside bombs and other explosions. In order to identify those troops who might have injuries that show no symptoms now, but might turn into serious problems years from now, the U.S. Army is using a new brain scanner combines gamma rays and radioisotopes to identify subtle damage to the brain.

Normally, brain injuries (concussion) from the of nearbyexplosions, appear to wear off after a few hours, or days, of rest. What has been missed until now were the long term effects. Too many concussions has long been known to cause permanent and severe brain damage. Boxers who took too many blows to the head would, in their later years, become permanently disoriented and mentally disabled. This came to be called punch drunk. But as more professional football and hockey players suffered concussions, experts in sports medicine began to notice patterns in how a few concussions could cause serious, and delayed, long term damage. Better diagnostic tools (like MRI) made it possible to see the damage early on.

Progress in treating sports injuries, especially head concussions, have provided the U.S. Army with a large body of experience on how to spot, and treat concussions (from explosions) and the resulting brain injuries. The army developed guidelines for combat commanders to apply for troops who suffer concussions, giving them several days of rest, or sending them for MRI and other tests to make sure there is no serious damage. Like professional athletes, soldiers who have suffered a certain amount of concussion injury will be removed from combat duty. This in itself is nothing new. For decades, combat soldiers have been shifted to less strenuous jobs when they suffered permanent muscular or skeletal injuries from combat, or even peacetime, operations. Paratroopers, or even airmobile infantry who jump a few feet out of helicopters with carrying a hundred pounds of gear, often suffer permanent back or other injuries. Tank crews suffer similar risks jumping off their tanks, or overexerting themselves pulling maintenance on their armored behemoths. Just training for combat is a very physically demanding task.

Concussions, first encountered on a large scale during World War I, which gave rise to the term "shell shock," was the result of the increasing use of high explosive shells and hand grenades. This created large numbers of soldiers with no visible wounds, but who were definitely in a state of shock. Shell shock eventually came to be renamed combat fatigue, because it wasn't the numerous blast injuries that caused so many soldiers to go into a long term state of mental distress, but prolonged exposure to the stresses of combat.

These long term injuries are nothing new, and with thousands of World War II combat veterans studied for over half a century, there is more and more data to pinpoint what kind of injuries we are dealing with, and what their long term effects are. The big breakthrough has been the ability to spot these subtle injuries early on.