INTRODUCTION: In recreational skiing, 40-64% of all injuries occur at the lower extremities, predominately at the knee (31%) (Klous, 2007). These high percentages clearly show the need for systematic research to determine joint loading on the lower extremities in skiing. So far, only rough estimations of joint loading in skiing are reported (Quinn & Mote, 1992). The present study is part of a larger project in which 3D joint loading on the lower extremities in carved and skidded ski and snowboard turns were determined using inverse dynamics. The purpose of the present study is to compare knee joint loading at the inside and outside leg in carved and skidded ski turns. It is supposed that knee joint loading is higher in carving than in skidding. METHOD: Four subjects participated in the study. Kinetic data were collected with mobile force plates (KISTLER), placed between riser and binding (200 Hz). Kinematic data of both legs, pelvis, and trunk were collected with five synchronized analogue panning, tilting and zooming cameras (50Hz). 3D marker positions were manually digitized and calculated with Simi Motion. Further analyses of kinetic and kinematic data and the inverse dynamics were carried out with specifically developed Matlab Software. To calculate segment inertial Parameters, an extended Version of Yeadon (1990) was developed. To compare knee joint loading between carving and skidding and the inside and outside leg, each run was divided in three equal phases that correspond to the functional aspects of the turning techniques. RESULTS: Table 1 show results for each force (Fmed-lat, Fant-post, Faxial) and moment component (Mflex-ext, Mab-ad, Mint-ext) for the inside (IN) and outside (OUT) leg in a carved (C) and skidded (S) ski turn for only the steering phase. DISCUSSION: Anterior-posterior and axial forces at the knee joint are the largest at the outside leg in carving. Medial-lateral forces as well as abduction-adduction and internal-external rotation moments are the highest at the outside leg in skidding. Flexion-extension moments are larger at the inside leg than at the outside leg in both carving and skidding. CONCLUSION: It can not be concluded that knee joint loading is higher in carving than in skidding. Differentiation between forces and moments and their components is required. Furthermore, knee joint loading in alpine skiing is considerably high in carved and skidded turns. Therefore, it seems that frequency and severeness of injury is not related to technique.
© Copyright 2007 4th International Congress on Science and Skiing. Julkaistu Tekijä University of Salzburg. Kaikki oikeudet pidätetään. / Kääntänyt https://www.DeepL.com/Translator