A Study of Lumbosacral Orientation under Varied Static Loads

A predictable reorientation of the sacrum and lumbar spine for both men and women as a function of torso and knee angles is disclosed.

Abstract

This paper describes a study of lumbar and sacrum orientations in select standing postures with the patient holding different loads in the hands. Vertebral rotation data were gathered from two young, healthy men and two young, healthy women while they performed static lifts at two load levels and in postures ranging from erect standing to deep squatting. The results disclosed a predictable reorientation of the sacrum and lumbar spine for both men and women as a function of torso and knee angles. Nonlinear second-order regression models of torso angle and knee angle versus reorientation angle were fit to the data with resulting r2 values of about 0.89. Load was not found systematically to affect the sacrum/lumbar reorientation.