Longitudinal Foot Arch Height And Risk Of Injury In Us Army Basic Combat Training

Abstract

A prior study (Cowan, Arch Fam Med, 2:773, 1993) suggested that high longitudinal foot arches were associated with injury incidence during military training; however, another study (Kaufman, Am J Sports Med, 27:585, 1999) using different methods showed little relationship between arch height and injury risk. PURPOSE: This study examined the relationship between a direct measurement of longitudinal foot arch height and injury incidence during United States Army Basic Combat Training (BCT). METHODS: Bilateral arch height was measured in 2,691 male and 1,270 female U.S. Army recruits prior to beginning BCT. Arch height was defined as the distance from the standing surface to the inferior border of the navicular tuberosity. Injuries occurring during the 9-week BCT cycle were obtained from medical records. Cox regression was used to examine injury risk among individuals with the highest 20% of arch heights (H) and individuals with the lowest 20% of arch heights (L) relative to the middle 60% of the arch height distribution (M). The M group was defined as baseline injury risk (equal to 1.00). Cox regression was used to determine hazard ratios (HRs) and 95% confidence intervals (95%CIs). RESULTS: For men, the L group was at slightly higher injury risk for the left arch height (HR (L/M)=1.13, 95%CI= 0.99-1.34) but not for right arch height (HR (L/M)=1.02, 95%CI= 0.87-1.20). The male H group showed injury risk similar to the M group for both the left (HR (H/M)=1.02, 95%CI= 0.87-1.19) and right foot (HR (H/M)=0.98, 95%CI= 0.84-1.15). For women, the L group showed little increased risk of injury relative to the M group for the left (HR (L/M)=1.11, 95%CI= 0.94-1.32) or right (HR (L/M)=1.09, 95%CI= 0.92-1.29) foot. The female H group also showed little increased risk relative to the M group for either the left (HR (H/M)=1.11, 95%CI= 0.94-1.32) or right (HR (H/M)=1.09, 95%CI= 0.92-1.29) foot. CONCLUSION: Direct measurement of the height of the longitudinal foot arch indicated that subjects with high and low arches were not at substantially elevated injury risk during Army BCT. These findings are in consonance with those of Kauffmann, et al. (Am J Sports Med, 27:585, 1999).