RISK-FACTORS FOR STRESS-FRACTURES IN TRACK AND FIELD ATHLETES - A 12-MONTH PROSPECTIVE-STUDY

The aim of this 12-month prospective study was to investigate risk fac tors for stress fractures in a cohort of 53 female and 58 male track a nd field athletes, aged 17 to 26 years. Total bone mineral content, re gional bone-density, and soft tissue composition were measured using d ual-energy x-ray absorptiometry and anthropometric techniques. Menstru al characteristics, current dietary intake, and training were assessed using questionnaires. A clinical biomechanical assessment was perform ed by a physical therapist. The incidence of stress fractures during t he study was 21.1%, with most injuries located in the tibia. Of the ri sk factors evaluated, none was able to predict the occurrence of stres s fractures in men. However, in female athletes, significant risk fact ors included lower bone density, a history of menstrual disturbance, l ess lean mass in the lower limb, a discrepancy in leg length, and a lo wer fat diet. Multiple logistic regression revealed that age of menarc he and calf girth were the best independent predictors of stress fract ures in women. This bivariate model correctly assigned 80% of the fema le athletes into their respective stress fracture or nonstress fractur e groups. These results suggest that it may be possible to identify fe male athletes most at risk for this overuse bone injury.