January 4, 2008: As part of the efforts to improve military medical care, 1,145 American paratroopers have had a six ounce sensor added to the back of their helmets. They will wear the device for over a year, until they complete a yearlong tour in Afghanistan. The tiny sensor package can record 527 different types of movement. In particular, U.S. Army medical researchers are interested in what happens when troops are hit by the blast of an explosion. There's been a lot of that in the last five years because of the wide use of roadside bombs by terrorists. The troops will download data from the device once a month. The battery lasts six months. This device is the first test of a long planned effort to equip troops with medical sensors, in order to assist in treatment for battlefield wounds. Sort of like a "black box" for those on the battlefield. These devices will ultimately hook into the battlefield Internet, and alert medics, and medical personnel in general, that someone is hurt, to what extent and where they are. These devices, as the current use shows, are also able to collect precise injury data for research on trends, and the details of the injury process. This makes it possible to build better protective devices (helmets and body armor) and develop more effective treatments.