By Richard Lister
BBC News, Washington
Soldiers in combat bear heavy mental and physical loads
US soldiers in Iraq and Afghanistan are more likely to be withdrawn from the battlefield due to back or joint pain than combat injuries, a study says.
A survey in a UK medical journal of US evacuees treated at a military hospital in Germany from 2004 to 2007 shows that psychiatric disorders also increased.
The study, in the Lancet, looked at the injuries suffered by 34,000 US military personel in Iraq and Afghanistan.
It found only 14% percent of medical evacuations were due to combat wounds.
Back, joint and muscle pain were instead the leading medical problems suffered by soldiers, accounting for almost one-quarter of all injuries.
The analysis, carried out by researchers at the Johns Hopkins School of Medicine in Baltimore, said the bulk of the other evacuations were also caused by everyday medical problems like gastro-intestinal infections, respiratory diseases, chest and spinal pain.
But they also noted that the rate of psychiatric problems was increasing sharply - almost tripling in Iraq over the course of the study to 14%, and nearly doubling in Afghanistan, to 11%.
Non-combat injuries also caused most of the American medical evacuations during the wars in Vietnam and Korea.
But this study is prompting the US Department of Defence to look at the weight of equipment that soldiers are routinely required to carry, and the length of their tours of duty.