[Biomechanic study of sternal movements in adult man (author's transl)].

The study of the sternal movements by the use of biometry mensurations of 62 young adult men allows to precise the respiratory variations of the Louis's angle and sternal displacements in the sagittal plane. The sternal movements are successivly considered in standing and horizontal positions, at three respiratory moments corresponding to the respiratory rest, the forced inspiration and the forced expiration. The sternal displacements in the sagittal plane are the resultant of backward and forward movements and elevation and lowering movements. In standing position the amplitude of the forward movements can be compared to these of the backward movements while the amplitude of the elevation movements is four times more important than that of the lowering movements. In horizontal position the amplitude of the forward movements is twice more important than that of the backward movements and the amplitude of the elevation movements is twice more important than that of the lowering movements. The correlation research between the sternal movements and the vital capacity allows to precise that the vital capacity appears essentially in correlation with the maximum of the amplitude of the Louis's angle movements in horizontal position and with the forward and backward sternal movements in standing and horizontal positions.