Modeling of kinetic risk factors for exercise related lower leg pain in collegiate female track and field athletes

Abstract

Exercise related lower leg pain is a common problem among the physically active, occurring more often in women than men. The exact mechanism underlying the most common causes of this condition in physically active individuals is controversial. Exercise related lower leg pain (ERLLP) is a broad diagnosis representing the shared clinical manifestations of medial tibial stress syndrome, tibial stress fractures (TSF) and chronic exertional compartment syndrome. Previous ERLLP research has focused on identifying associated risk factors and is limited by retrospective research designs, using different methods of injury modeling that fail to consider dynamic free moment variables or changes due to exercise. Free moment (FM) has been associated with a history of TSF but has not been examined relative to ERLLP. Therefore, the purpose of this study was to examine kinetic risk factors associated with both previous or subsequent ERLLP in female, NCAA Division I intercollegiate track and field athletes using two different injury models. Subjects were 31 female athletes from the same NCAA division I track and field team. Kinetic analysis was performed prior to and following an exhaustive bout of treadmill exercise. Injury history was collected prior to testing and subjects were subsequently tracked through the three month competitive season for the development of ERLLP resulting in activity modification. Injury modeling using logistic regression was based on pre-exercise kinetic measures and fatigue-induced changes in kinetic variables. Injury probability was modeled using two separate injury classifications (retrospective vs. prospective) and two separate injury models (one leg per subject vs. two). Significant models, which included FM variables, were found for retrospective injury from both pre-exercise and fatigue-induced gait kinetics. No significant models for predicting prospective injury were found. While retrospective models were similarly effective using either injury model, these models were not effective for predicting the development of ERLLP. Consequently, while either injury model may be used effectively in predicting previous ERLLP in female track athletes, care should be taken when attempting to predict injury development based on retrospective modeling.