ABSTRACT
Sitting is the most common posture in today’s workplace; those who spend long periods of time sitting on the job range from office workers to vehicle drivers to assembly line workers. Pelvic orientation is integral to seated postures and lumbar spine position. Zacharkow maintains that the key to proper seat support is proper sacral and pelvic support, which prevents the posterior rotation of the pelvis and lumbar kyphosis. Adrichem and Korst tested 250 schoolchildren using the skin traction method described by Schober; this approach was found to produce accurate measurement of lumbar spinal flexion independent of age, body length, lumbar length and degree of lumbar lordosis. Additionally, the ability to measure the lumbar spine curvature and pelvic orientation of a seated subject would provide the basis for improving seating, particularly in the work environment. The measurement of lumbar curvature among seated subjects is particularly difficult when they are leaning against a backrest, since their backs cannot be observed or accessed.
