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Purpose The higher prevalence of knee injuries among adolescent females may be related to female pubertal development. The aim of this study was to determine whether girls exhibit higher triplanar knee and hip moments with more advanced pubertal development during a single-limb landing. Methods Lower-limb biomechanics of 93 females grouped according to prepubertal (n = 31), early/midpubertal (n = 31) and late/postpubertal (n = 31) development performed a single-limb drop lateral jump. Peak triplanar knee moments and hip moments at the time of peak knee moments were derived from a Vicon motion analysis system and concealed force plate. Joint moments were normalized to body mass (N·m·kg-1), height (N·m·kg-1·m-1) and body mass by height (N·m·kg-1·m-1). Between-group differences were analyzed using a one-way ANOVA with Pearson correlations used to explore relationships between joint moments and anthropometrics. Results Girls at latter stages of puberty landed with higher triplanar knee moments and hip flexion moment at time of peak knee flexion moment when normalized separately to body mass and to height (P < 0.05). In contrast, hip internal rotation moments at time of peak knee internal rotation moment normalized to body mass and to body mass by height were lower in late/postpubertal girls compared to their early/midpubescent (P = 0.01) and prepubescent (P = 0.01) counterparts. Positive correlations were identified between triplanar knee moments and body mass (r = 0.73-0.91, P < 0.001) and height (r = 0.61-0.89, P < 0.001) for all participants. Conclusions Higher triplanar knee and sagittal plane hip moments with more advanced pubertal stage is attributed to growth-related increases in body mass and height. Given that growth is a crucial element of puberty, further research is required to quantify the impact of pubertal growth-related changes on risk of adolescent female anterior cruciate ligament injury.

Purpose This study aimed to investigate whether knee and hip running moments differ across stages of female pubertal development. Methods This was a cross-sectional study comparing the barefoot running moments of 91 prepubertal (n = 31, Tanner stage I), early/midpubertal (n = 30, Tanner stages II and III), and late/postpubertal (n = 30, Tanner stages IV and V) girls. External peak moments for knee abduction (KAbM), knee adduction (KAM), knee flexion (KFM), and knee internal rotation (KIRM) were analyzed. Secondary measures of hip adduction moment at the time of peak KAbM and hip flexion moment at the time of peak KFM were also derived. Between-group differences were analyzed using a series of one-way ANOVAs and ANCOVAs. Results At the knee, the late/postpubertal girls displayed a higher peak KFM and KAM compared with the prepubertal group (P < 0.05), and the early/midpubertal group exhibited a higher peak KFM than the prepubertal group (P = 0.034). No between-group differences were found for peak KAbM or KIRM (P > 0.05). At the hip, both the late/postpubertal (P = 0.03) and early/midpubertal girls (P = 0.039) ran with a lower hip adduction moment at the time of peak KAbM than the prepubertal girls. The hip flexion moment at the time of peak KFM in late/postpubertal girls was also significantly lower than both the early/mid- and prepubertal girls (P < 0.001). Conclusion Girls at the latter stages of puberty exhibit higher peak external knee flexion and adduction moments, but not abduction or internal rotation moments. This may be partly attributed to a lower hip flexion but higher hip abduction moment at the time of peak knee moments. Future research should examine whether these differences in knee kinetics between pubertal stages have implications for knee injuries such as patellofemoral pain syndrome. © 2018 by the American College of Sports Medicine.

Microsoft Kinect for Windows v2 is a motion analysis system that features a markerless human pose estimation algorithm. Given its affordability and portability, Kinect v2 has potential for use in biomechanical research and within clinical settings; however, recent studies suggest high inaccuracy of the markerless algorithm compared to marker-based motion capture systems. A novel tracking method was developed using Kinect v2, employing custom-made colored markers and computer vision techniques. The aim of this study was to test the accuracy of this approach relative to a conventional Vicon motion analysis system, performing a Bland–Altman analysis of agreement. Twenty participants were recruited, and markers placed on bony prominences near hip, knee and ankle. Three-dimensional coordinates of the markers were recorded during treadmill walking and running. The limits of agreement (LOA) of marker coordinates were narrower than − 10 and 10 mm in most conditions, however a negative relationship between accuracy and treadmill speed was observed along Kinect depth direction. LOA of the surrogate knee angles were within − 1.8° 1.7° for flexion in all conditions and − 2.9° 1.7° for adduction during fast walking. The proposed methodology exhibited good agreement with a marker-based system over a range of gait speeds and, for this reason, may be useful as low-cost motion analysis tool for selected biomechanical applications. © 2018 IPEM

Dans la perspective de comprendre, d'aider et de soutenir davantage les personnes qui vivent avec une maladie mentale, de nombreux écrits théoriques et études empiriques ont été publiés sur le rétablissement au cours des deux dernières décennies. Toutefois, la définition de ce concept ne fait pas l'objet d'un consensus. Une autre limite concerne la documentation de l'expérience du rétablissement du point de vue des usagers au Québec, notamment à l'égard de son articulation avec le concept de santé mentale. Le but de cette étude est de comprendre l'articulation entre la santé mentale et la conception du rétablissement chez des adultes vivant avec une maladie mentale. Elle vise à déterminer la signification donnée à la santé mentale et au rétablissement et de même qu'à explorer le lien entre la santé mentale et la conception du rétablissement chez des adultes vivant avec une maladie mentale. L'approche théorique de la conception élargie du rétablissement de Provencher et Keyes (2010, 2011) est ici utilisée puisqu'elle fait état du rétablissement complet. La théorie intermédiaire du caring de Watson (1988; 1998; 1999; 2008) sert également de cadre disciplinaire afin d'orienter la disposition de l'étudiante, notamment à l'égard du lien chercheur-participant ainsi que pour guider l'exploration de la santé mentale et du rétablissement. L'échantillon de convenance est composé de 15 adultes vivant avec une maladie mentale (13 femmes et 2 hommes) et des entretiens en profondeur permettent d'explorer la signification donnée à la santé mentale et au rétablissement. L'analyse des données repose sur la méthode phénoménologique herméneutique proposée par Van Manen (1997, 2002). Les résultats mettent en évidence trois niveaux hiérarchiques, soit primaire, intermédiaire et supérieur, ce dernier étant le plus englobant. Ces niveaux se rapportent à la signification de la santé mentale d'une part, et la signification du rétablissement d'autre part. Chaque niveau correspond à un proces