A prospective study of 295 infantry recruits has shown that the mediolateral width of the tibia measured radiographically at each of three different levels in the bone had a statistically significant correlation with the total incidence of stress fractures as well as with those in the tibia alone or the femur alone. A narrow tibial width was shown to be a risk factor, but cortical thickness was not found to be significant.

In a prospective study of 295 male Israeli military recruits a 31% incidence of stress fractures was found. Eighty per cent of the fractures were in the tibial or femoral shaft, while only 8% occurred in the tarsus and metatarsus. Sixty-nine per cent of the femoral stress fractures were asymptomatic, but only 8% of those in the tibia. Even asymptomatic stress fractures do, however, need to be treated. Possible explanations for the unusually high incidence of stress fractures in this study are discussed.