Postural Sway as a Predictor of Lateral Ankle Joint Sprain in the Collegiate Soccer Athlete

This study was designed to determine if postural sway data could predict the incidence of lateral ankle injury in collegiate level soccer players. Postural sway data was collected using the Chattecx Balance System. At the beginning of the fall 2000 soccer season, 33 subjects were tested under sixteen different conditions. These test conditions involved single leg stance with both the dominant and non-dominant lower extremities, a static and dynamic force platform, eyes open and eyes closed, and shoes on and shoes off variables. The athletes were then followed throughout the soccer season and the incidence of ankle injury was recorded. At the conclusion of the playing season the postural sway data along with the injury data were analyzed using a stepwise discriminant analysis and a two-way analysis of variance with repeated measures. One testing condition was found to significantly predict ankle injury. Postural sway data recorded from that test condition which involved a dynamic platform, the dominant lower extremity, eyes open, and shoes off, (condition M) were found to have predictive characteristics for ankle injury. Under condition M, 72.7% of the 33 subjects were correctly classified as either injured or uninjured. During the season six athletes incurred lateral ankle injuries and of those six, 100% were classified correctly as injured under condition M. However, nine non-injured athletes were incorrectly classified as injured. Analysis of variance demonstrated significant interaction among conditions. When comparing eyes open to eyes closed conditions there was a significant difference as expected. In addition, a significant difference was demonstrated when comparing static and dynamic testing conditions. From our results we found evidence that it may be possible to predict those athletes at greater risk for ankle injury using specific single leg stance conditions to measure postural sway data. However, further research with greater numbers of participants is needed to determine why only a dynamic platform, dominant lower extremity, eyes open and shoes off test condition, (condition M) was found to be of significantly related to ankle injury