Anatomical and roentgenological basis for the study of the lumbar spine with the body in the suspended position.
Roentgenological investigation of the lumbar spine was done in the standing and suspended position in 100 healthy adult male volunteers. Spinal and external morphology were studied. The aim of this work was to identify eventual correlations between the modifications of shape and size of the suspended lumbar spine and external morphology. Such correlations were sought to establish a functional approach to anthropometry. The results of this study demonstrated that the suspended position led to lengthening of the spine in 70% of the subjects examined, shortening of the spine in 22% and mainly straightening of the spine in 8%. Extension of the lumbar spine resulting from the suspended position is dependent upon tonic muscle activity and the relations between the observed spinal modifications and external morphology are difficult to establish. Nevertheless, anthropometric profiles and spinal features allow identification of certain influential external morphological parameters. Furthermore, the results of this study confirm those of others devoted to elongation of the lumbar spine under horizontal traction or suspension and lead to practical conclusions.