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Abstract: Background: The dynamics behavior of patients with idiopathic scoliosis obviously requires some biomechanical compensatory strategies. Our objective is to analyze the ground reaction forces (GRF) exerted during gait initiation in order to determine the dynamic consequences of idiopathic scoliosis. Methods: Ten adolescent girls suffering from idiopathic scoliosis with a right thoracic curvature (Cobb>15°) and 15 healthy adolescents participated in this study. Two force plates were used to record the ground force evolution for the right and left limbs tested during gait initiation. Results: Whichever limb was used to initiate gait, gait initiation duration was found to be significantly longer in persons with scoliosis than in healthy subjects. In the scoliosis group (SG), the impulses, occurrences and forces values were also greater than in healthy subjects. Under the stance foot, the anteroposterior and vertical forces were always increased. Under the swing foot, the SG showed the same characteristics associated to decreased mediolateral impulses parameters. Even greater differences were observed between these two groups in terms of peak occurrences during left-limb gait initiation. The intragroup comparisons only unveiled very few differences between the two limbs for the control group (CG), whereas significantly higher values were recorded for the group of scoliosis patients when gait was initiated with the left limb rather than with the right one. Conclusion: For patients with scoliosis specific dynamic behavior adjustment are made during gait initiation patterns, for both limbs in order to maintain balance during gait to compensate for their spine deformation. Patients with scoliosis always showed slower dynamic patterns than healthy controls. These results show the importance of including specific evaluation and dynamic physical rehabilitation for patients with idiopathic scoliosis. [Copyright &y& Elsevier]

Abstract: Swimming fins are used for muscular training but we do not really know how fins affect muscular training. In this way, the purpose of this present study was to examine the influencing factors of fin designs and swimmer kinematics on the muscle activity. Eight individuals took part in this study which consists of eight tests, thereof one standard, four with prototyped fins and three with different kinematics. The surface electromyography (EMG) of lower limb superficial muscles was recorded. The muscle activity was significantly higher for highest frequency strokes. No EMG difference was found whilst comparing different amplitudes or different stiffness. Heavy fins significantly train the shank more, whereas short ones have more impact on the thigh and the buttocks. [Copyright &y& Elsevier]

Abstract: Introduction: Adolescent idiopathic scoliosis (characterized by a morphological deformation of the trunk) prompts the development of new postural control strategies. This adaptation has an influence on the dynamics of motor behaviour. The present study analysed ground reaction forces during lateral stepping in order to highlight the dynamic consequences of idiopathic scoliosis. Material and methods: Ten adolescents suffering from idiopathic scoliosis with right thoracic curvature (Cobb angle ≥15°) and 15 healthy adolescents participated in the study. We used two force platforms to record ground reaction forces for the right and left legs during large and small lateral steps (LSs). Results: Our results revealed intergroup and interlimb differences for both types of step. For small LSs, right-side (i.e. convexity side) initiation induced a significant increase in the ground reaction force impulse during the postural phase for the scoliotic group, when compared with the control group. For large LSs, left-side (i.e. concavity side) initiation induced a significant increase in ground reaction force impulse during the landing phase only. Patients always displayed slower dynamic behaviour than healthy controls. For both stepping sides, the asymmetry index (AI) was higher in the scoliotic group than in the control group (0.2≤AI≥85 in the scoliotic group versus 0.124.4 in the control group). Furthermore, the scoliotic group showed a significant increase in the variability of the dynamic parameters (>8%). Conclusion: In scoliotic subjects, lateral stepping prompts specific dynamic behaviour affecting both limbs, in order to maintain balance during movement despite spinal deformation. This stepping task could be used in future studies to identify specific motor strategies. [Copyright &y& Elsevier]

Résumé Objectifs L’objectif de cette revue était d’examiner, chez les enfants, l’influence des chaussures minimalistes sur la biomécanique de course et d’établir une analyse théorique de l’influence de ce type de chaussure sur le risque de blessure. Actualités Entre 8 et 15 ans, les stress répétés induits par la pratique sportive régulière et les poussées de croissance que connaissent les enfants sportifs les rendent enclins aux blessures de sur-sollicitation. Les plus communes pour le membre inférieur sont les maladies d’Osgood-Schlatter et de Sever. Le premier lien entre le corps et le sol étant la chaussure, cette dernière peut être de première importance concernant le risque d’apparition de ces pathologies. Il est suggéré que l’utilisation de chaussures minimalistes modifierait la biomécanique de course et donc potentiellement le risque de blessure. Perspectives et projets De futures investigations sont nécessaires pour identifier, au cours du temps, si les enfants adaptent ou non leur motricité à l’utilisation de chaussures minimalistes et si le port de ces dernières influence le risque de blessure de sur-sollicitation. Conclusion Par rapport aux chaussures conventionnelles, l’utilisation de chaussures minimalistes induit généralement un placement du pied plus à plat avec une cheville plus en flexion plantaire lors de l’impact avec le sol et une flexion du genou moins importante pendant la phase d’appui. Il semble que ces modifications conduisent à une réduction des forces de tension au niveau du genou et qu’elles pourraient diminuer le risque de maladie d’Osgood-Schlatter. Concernant la maladie de Sever, l’analyse biomécanique n’est pas concluante à cause de la complexité de sa patho-mécanique. Le port de chaussures minimalistes devrait diminuer les forces compressives sous le talon par une redistribution de la pression sur l’ensemble de la face plantaire ou sous l’avant-pied mais pourrait en contrepartie augmenter les forces de tension au niveau de l’insertion du tendon d’Achille sur le calcanéum. Summary Objective The objective of this review was to examine the influence of minimalist shoes on the running biomechanics of children and to establish a theoretical analysis of the influence of this type of shoes on the injury risk. News Between 8 and 15 years old, repeated stress induced by the regular practice of sports and growth spurts experienced by active children make them prone to overuse injuries. The most common for the lower body are Osgood-Schlatter and Sever's disease. The first link between the body and the ground being footwear, the latter can be of primary importance in the occurrence of these pathologies. It was suggested that the use of minimalist shoes would modify the running biomechanics and thus potentially the injury risk. Prospects and projects Further investigations are needed to identify whether, over time, children adapt or not their behaviour to the use of minimalist shoes and whether the wearing of this type of shoes influences the overuse injuries risk. Conclusion Compared with conventional shoes, the use of minimalist shoes generally induces a flatter foot placement, with a more plantar-flexed ankle at ground contact and less knee flexion during stance phase. It seems that these modifications lead to a reduction of tensile forces at the knee and may decrease the risk of Osgood-Schlatter disease. Concerning Sever's disease, the biomechanical analysis was not conclusive due to the complexity of its pathomechanics. The wearing of minimalist shoes should decrease heel compressive forces through a pressure redistribution under the whole plantar surface or under the forefoot but may in counterpart increase tensile forces at the Achilles tendon insertion site onto the calcaneus. [ABSTRACT FROM AUTHOR]