Risk factors for musculoskeletal injuries for soldiers deployed to Afghanistan.

PURPOSE This study determined injury incidence and examined the association between musculoskeletal injuries and potential intrinsic and extrinsic risk factors. METHODS This retrospective cohort study involved a survey of 593 volunteers from two battalions of a Stryker Brigade Combat Team upon completion of a 12-mo deployment to Afghanistan. The survey included questions on physical characteristics, work duties, equipment worn, fitness training, and injuries experienced during the deployment. RESULTS Of the surveyed soldiers, 45% sustained an injury during the deployment. Total injuries resulted in 5049 d of limited duty, an average of 8.5 d per injury. The body regions with the largest numbers of injuries were the low back (17.4%), knee (12.7%), and shoulder (10.0%). The majority (65%) of injuries occurred while working. The most frequent activities soldiers reported as the cause of injury were lifting and carrying (9.8%), dismounted patrolling (9.6%), and physical training (8.0%). Older age, higher enlisted rank, female sex, months deployed, more time spent standing, longer strength training sessions, heaviest load worn, and heavier or more frequent lifting tasks were all associated with injury. DISCUSSION Tasks requiring physical energy expenditure such as load carriage, lifting, or standing resulted in an increased risk of musculoskeletal injury in this study. Lifting/carrying, dismounted patrols, and physical training were associated with 26% of musculoskeletal injuries. The weight of loads carried and lifting may be exceeding the work capacity of the soldiers, resulting in injury. These injuries in turn limit available work days for military units, reducing combat power.