Musculoskeletal Injury in U.S. Army Active Duty Soldiers: Examining Prevalence and Protective Factors

Introduction: Musculoskeletal injury (MSI) – including injuries to the bones, joints or muscles – is the largest health and disease burden facing military and civilian populations. This project examined the prevalence of non-combat musculoskeletal injuries (MSIs) and investigated the relationship between psychological strengths and non-combat related MSI in U.S. Army active duty Soldiers who served from 2009 to 2016.

Methods: We leveraged existing Global Assessment Tool (GAT), Defense Manpower Data Center (DMDC), and Military Health Systems Data Repository (MDR) data housed in the Person-Event Data Environment (PDE), a secure Army data repository and analysis environment. MSI-related healthcare encounters were quantified using diagnostic code data from Military Treatment Facilities. In order to better understand the nature of MSI encounters in the Army, we conducted a series of three studies. In Study 1, we examined the prevalence of MSIs among 1,080,622 active duty Army Soldiers, overall and by gender. In Study 2, we applied survival analysis techniques to a sample of 24,746 active duty Army Soldiers in order to investigate the relationship between baseline psychological strengths (Optimism, Positive Affect, Coping, and Adaptability) and MSI incidence (defined as an MSI-related encounter at a Military Treatment Facility). In Study 3, we examined a subset of 4,759 Soldiers from Study 2 who completed a second psychological strengths survey (i.e., GAT) approximately one year later and tested whether changes in psychological strengths over a one year period are associated with subsequent MSI risk.

Results: In Study 1, we found that over an 8-year study period, two-thirds (66.87%) of the Soldiers we examined had an MSI-related encounter at a Military Treatment Facility. Additionally, a higher percentage of female, compared to male, Soldiers sought treatment for an MSI during the study window (71.84% vs. 65.44%, respectively). In Study 2, we found that greater baseline psychological strengths (including Optimism, Positive Affect, Coping, and Adaptability) were associated with a small decreased risk (less than 10%) of incident MSI – related encounters. In Study 3, we found that increases in Optimism and Coping were also related to a decreased risk (less than 10%) of developing an MSI.

Conclusions: MSI remains a significant health issue for both male and female active duty Soldiers and is a substantial burden on Military Treatment Facilities. Future research should examine the extent to which increasing Optimism, Coping, Adaptability and Positive Affect through targeted interventions can also effectively reduce Soldiers’ MSI risk, thereby improving the readiness of our troops and reducing the Army’s MSI-related health care costs.