Lumbar Spine Fractures Within a Complete American Cohort

Abstract

Retrospective database review. To describe the incidence of, and risk factors for, lumbar spine fractures within the population of the US military. SUMMARYOF BACKGROUND DATA: Fractures of the lumbar region are an important health concern; however, the epidemiology of this injury has not been extensively studied in the United States. International Classification of Diseases, Clinical Modification, Ninth Revision codes for lumbar spine fractures were used in a search of the Defense Medical Epidemiology Database, identifying all individuals who sustained such injuries between 2001 and 2010. The database was also used to obtain the complete number of individuals serving in the Armed Forces over the same time period. Information regarding race, rank, branch of service, sex, and age was obtained for all individuals identified as having lumbar spine fractures as well as for the whole military population. The incidence of lumbar spine fractures was determined for the cohort. Unadjusted incidence rates were derived for risk factors and multivariate Poisson regression analysis, controlling for all other risks, was used to obtain adjusted incidence rate ratios and identify statistically significant risks for lumbar fractures. Between 2001 and 2010, the overall incidence of lumbar fractures was 0.38 per 1000 person-years. Male sex, white race, enlisted ranks, service in the Army and Marines, and age were found to be significant predictors of lumbar spine fracture. Service in the Army demonstrated the highest rate of lumbar fractures (0.48 per 1000 person-years). This investigation is the first to document the incidence and postulate risk factors for lumbar spine fracture in an American population. In this study, males, whites, enlisted personnel, those serving in the Army and Marines, and individuals aged 20-24 or greater than 40 were found to be at an increased risk of lumbar fracture.