Recordings of the movement at the intervertebral segment L5-S1: a technique for the determination of the movement in the L5-S1 spinal segment by using three specified postural positions.

The pathomechanism of low-back pain generation is not understood very well. Functional disturbances of motion at the individual segmental level appear to play a role in many cases. In this study a technique of numeric analysis of radiographic observations of the lumbar spine is developed by which the authors are able to assess the displacement of the two components of the L5-S1 motion segment in the sagittal plane when the subject assumes three specified standard postural positions.