Posted : Sunday Jun 6, 2010
SAN DIEGO — Navy researchers are preparing to launch a study aimed at preventing injuries suffered by Marines who carry heavy rucksacks into combat.
“The intent is to see if we can identify indicators of imminent injury ... or the fact that you have reached the tolerance point for load carriage,” said James Hodgdon, a research physiologist at Naval Health Research Center in San Diego. Navy medical officials and researchers are finalizing details of the two-year study and expect it will begin in a couple of months, Hodgdon said.
The study likely will include two groups of Marines: students at the School of Infantry-West at Camp Pendleton, Calif., and members of an infantry company preparing for deployment.
Some troops carry packs and weapons in combat that weigh 135 pounds or more. All that weight can injure even the most physically fit. Back strains, stress fractures, muscle sprains, herniated discs and other injuries occur with some frequency.
Researchers intend to study men only at this point. “The current focus is on infantry because they are the ones that will directly carry loads,” Hodgdon said.
Large study group
Large study group
By following several groups of infantrymen, researchers hope to track any physiological changes to their bodies that may manifest, such as inflammation or a breakdown of connective tissues. Once they identify any “useful indicators,” Hodgdon said, research teams will conduct lab experiments to determine safe and tolerable weights.
“If we can show what the load carriage limits are, to establish points of strain, then we can use that to guide any physical training programs that are developed” to address the issue, he said. Preventing these injuries may be as simple as introducing new conditioning programs.
The Corps’ quest to replace its Individual Load Bearing Equipment pack began late last year. Approved in 2004, before the proliferation of roadside bombs prompted the development of beefier body armor, ILBE has been criticized for its many shortcomings. Marines surveyed by the Corps in 2009 said the pack doesn’t work well with their armor, noting also that it causes chafing and pain in their knees, backs and shoulders. Ultimately, the Marines surveyed graded it “completely unacceptable.”
Key to the Navy study’s data collection efforts will be a vertical MRI machine. Unlike standard MRI machines, which take images of the body while the person lies on his back, vertical machines provide images of the spine as it’s aligned under the effects of gravity. That will show researchers how a combat load affects compression on the spinal disks, Hodgdon said.
Researchers hope to capture these MRI images while the Marines are wearing combat packs. But that may be tricky because some packs and their attachments may contain metal, which cannot be placed in an MRI machine. Packs that use aluminum frames could be a viable alternative, Hodgdon said.