External Rotation of the Hip

External rotation of the hip was found to have a statistically significant correlation with the incidence of stress fractures, in a prospective study among Israeli infantry recruits of possible anthropomorphic predictors of risk for stress fractures. Soldiers in whom hip external rotation was greater than 65° were at a higher risk for tibial and total stress fractures than those with external rotations of less than 65°. The mean hip external rotation in this study of 57° ± 9.3° was higher than in statistics reported in the American literature. The existence of a larger subpopulation with hip external rotation greater than 65° may partially explain why the reported incidence of stress fractures in the Israeli army is higher than that of the American army.