Introduction: The use of prophylactic knee orthoses is very common among Swiss ice hockey players to prevent recurrent lesions of the medial collateral ligament (MCL) and the anterior cruciate ligament (ACL). However, their effects are still widely discussed in the literature. Purpose of the Study: The purpose of this study is to assess the feasibility of a given protocol (recruitment, resources, data management, surveys...) for a future national study and to present the preliminary results of the prophylactic orthotics effects on recurrent injuries. Methods: Retrospective epidemiological pilot study.