Musculoskeletal Spine Injuries in U.S. Active Duty Service Members: Prevalence/Incidence, Healthcare Utilization, and Cost Analysis Spanning Fiscal Years 2016-2021.

Background: Low back pain and musculoskeletal injuries (MSKIs) of the Spine are the most common reason for U.S. active duty service members (ADSMs) to seek medical care. The purposes of this descriptive study were to report the prevalence/incidence, health care utilization, and health care costs attributable to Spine (thoracic, lumbar, sacral, and pelvic) MSKIs across the four major branches of service from Fiscal Years (FY) 2016 to 2021.

Materials and methods: This was a retrospective, longitudinal population study, including ADSMs from the Air Force, Army, Marine Corps, and Navy. Prevalence and incidence rates for Spine MSKIs, associated health care utilization, and costs were obtained by querying electronic health records (EHRs) from military treatment facilities, private sector care (PC) claims, and theater medical data from the Military Health System Data Repository from October 1, 2015 to September 30, 2021 (FY16-21). Utilization associated with Spine MSKIs in both the direct care (DC) and PC settings was classified into mutually exclusive outpatient encounter categories and acute inpatient stays. PC costs related to Spine MSKIs were captured per year.

Results: In FY21, 269,301 ADSMs sought care for Spine MSKI, representing 18.0% of the U.S. Armed Forces. The prevalence of Spine MSKIs ranged from 17.4 to 19.5% during FY16-21, with the highest annual prevalence among the Army (20.7-22.9%) and Air Force (19.0-22.6%). Across the study period, Soldiers had the highest share (47.8-50.4%) of DC outpatient encounters for Spine MSKI (primary or secondary diagnosis). The Air Force relied most heavily on PC for outpatient Spine MSKI care across the study period, where in FY21 Airmen accounted for 36.5% of the outpatient PC Spine MSKI encounters totaling $21,140,935 in PC costs. In FY21, total PC costs for Spine MSKI totaled $99,317,832.

Conclusions: This retrospective, descriptive study establishes prevalence/incidence, health care utilization, and PC costs for Spine MSKIs across the Services from FY16-21 and highlights the burden of Spine MSKIs among the U.S. Armed Forces, with costs amounting to over $99 million in PC reliance in FY21 alone.