Influence of selected examination postures on shape of the spine and postural stability in humans.

AIMS The accuracy of non-radiographic measurement of the spinal shape is influenced by postural sway (PS). The aim of this study was to determine whether certain examination postures prevent PS without changing key spinal characteristics. METHODS We tested 1) natural standing position (posture A), 2) fixation postures standing with the support of the upper limbs against a wall (posture B) and 3) standing with the support of the head and chest against a wall (posture C). There were examined 60 subjects; the examination of each posture was repeated five times in each individual by DTP-3 microcomputer position system. The spinal shape changes resulting from tested postures were assessed using t-test. The role of PS was assessed using standard deviations, and the significance of differences between the individual postures was determined using the F-test. RESULTS Compared to posture A, the fixation posture B did not have any significant influence on the degree of PS, but it significantly influenced the shift of the spine from the ideal vertical and its slope, although this did not result in spine curve deformation. The fixation posture C significantly reduced the PS compared to posture A; however, there were significant changes in the spinal shape. This fixation posture shifted significantly the spine from the ideal vertical and slope characteristics. CONCLUSION PS plays a role in the examination of spinal shape. Positions B and C did not meet the required criteria. Therefore, it is necessary to search for another examination position.