Characterizing Limb Loss and Absence in Military Health System Beneficiaries: Demographics, Causes, and Trends (2005-2023).

Introduction: An estimated 5.6 million individuals in the U.S. experience limb loss and absence, but national estimates exclude Military Health System (MHS) beneficiaries. The purpose of this study is to characterize MHS beneficiaries with limb loss and absence and estimate incidence and prevalence.

Material And Methods: We conducted a retrospective cohort study using data from the MHS Information Platform. Descriptive statistics were used to characterize the study population, including demographics, level of limb loss and absence, and etiology. Bivariate analyses between demographic characteristics and level of limb loss were conducted using analysis of variance and chi-square tests. The sample includes MHS beneficiaries diagnosed with limb loss or absence from 2005 to 2023. The study was determined exempt human subjects research by the Uniformed Services University of the Health Sciences Institutional Review Board.

Results: The cohort (118,587) was 64.6% male and 35.4% female, with mean age 58 years (SD = 23.4). Racial distribution included 49.8% White, 6.4% Black, and approximately 42.1% other or unknown. Service branches were Army (41.0%), Air Force (26.7%), Navy (19.7%), Marine Corps (7.0%), other (3.9%), Coast Guard (1.7%), and Space Force (0%). The majority were retired (46.2%) or other (32.0%), with a smaller portion active duty (12.0%) and dependents (9.9%). Levels of limb loss were 72% lower limb, 26.1% upper limb, and 2% unspecified. Causes included acquired absence (53.8%), traumatic amputation (34%), and congenital absence (12.1%). Bivariate analysis showed significant associations between demographics and limb loss levels (P = .000). Incidence (z = -2.43, P = .015) and prevalence (z = -13.69, P = .000) rates declined over 19 and 8 years, respectively.

Conclusion: This study highlights demographic characteristics, causes, and declining rates of limb loss and absence among MHS beneficiaries, providing a foundation for future research and informing clinical practices and policies to enhance care and resource allocation.