Description |
Hyperpronation has been shown to cause increased internal tibial rotation which, when prolonged, is thought to place increased stress on the Anterior Cruciate Ligament (ACL) and lead to a higher incidence of non-contact ACL injuries in sports. To date, no research has attempted to examine the relationship between hyperpronation and ACL injuries in a longitudinal model, although strong associations have been found in cross-sectional studies involving injured subjects. The cross-sectional data are strong enough to suggest that individuals with a hyperpronated foot will have a significantly greater number of ACL injuries. The purpose of this research was to complete a prospective cohort study examining the relationship between non-contact ACL injuries and hyperpronation and to determine the incidence rate of such injuries. It was hypothesized that the hyperpronation group would sustain more non-contact ACL injuries than the control group. Participants consisted of 141 NCAA Division I athletes among nine different sports. Out of the eligible participants, 125 met the inclusion criteria, and were separated into either hyperpronator (?9mm) or control ( <9mm) based on their navicular drop measurement. Measurements were taken prior to the start of the competitive season. Athlete tracking was completed over the course of 10 months by the supervising athletic trainer and principal investigator, whereby all non-contact ACL injuries were to be recorded. The mean navicular drop overall with all subjects combined (n=192) was 9.624.14mm. When separated by group, the HP group (n=109) mean navicular drop was 12.163.38mm compared to 6.161.88mm in the control group (n=83). A two-way ANOVA was conducted to examine the effect of group and gender on the navicular drop. A statistically significant main effect for group, F(2,186) = 207.42, p<.001 was identified, but there were no significant gender or gender by group interactions (p?0.05). No non-contact ACL tears recorded. While no non-contact ACL injuries were noted, navicular drop data in the HP group are similar to values found in previous research. Further study over a longer injury tracking timeframe needs to be conducted to determine if hyperpronation can be classified as a predictor variable for non-contact ACL injuries. |