Evaluation of the Use of the Smart Phone as a Screening and Evaluation Tool to Identify Knee Valgus During Dynamic Activities.

Evidence supports the use of two dimensional video analysis to assess the presence of dynamic knee valgus during generally used screening tasks, however there is limited evidence to support the use of the various smart phone applications as a time and money saving option for clinic use . Subjects that present to the clinic and display dynamic valgus at the knee during the lateral step down test will be given the option to participate in the study. If they consent to the study they will be evaluated with 2-Dimensional video analysis to determine the amount of valgus present at the knee during the lateral step down test. The subject will also have the smart phone attached to their lower leg and the amount of valgus will be concurrently measured by the selected application. The primary objective of this study is to determine the validity of an application on the smart phone to provide an objective measure of dynamic knee valgus. The secondary objective of this study is to determine the possibility of the use of the application as a source of feedback during neuromuscular re-education training in order to decrease or eliminate a subject's dynamic valgus collapse and subsequently decreased their risk for future injury.