Research article

Regional differences in lumbar spinal posture and the influence of low back pain

Tim Mitchell¹ , Peter B O'Sullivan¹ , Angus F Burnett^1,2 , Leon Straker¹ and Anne Smith¹

¹School of Physiotherapy, Curtin University of Technology, Kent St, Bentley, Western Australia, Australia

²School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Joondalup Drive, Joondalup, Western Australia, Australia

author email corresponding author email

BMC Musculoskeletal Disorders 2008, 9:152doi:10.1186/1471-2474-9-152

Published:	18 November 2008

Abstract

Background

Spinal posture is commonly a focus in the assessment and clinical management of low back pain (LBP) patients. However, the link between spinal posture and LBP is not fully understood. Recent evidence suggests that considering regional, rather than total lumbar spine posture is important. The purpose of this study was to determine; if there are regional differences in habitual lumbar spine posture and movement, and if these findings are influenced by LBP.

Methods

One hundred and seventy female undergraduate nursing students, with and without LBP, participated in this cross-sectional study. Lower lumbar (LLx), Upper lumbar (ULx) and total lumbar (TLx) spine angles were measured using an electromagnetic tracking system in static postures and across a range of functional tasks.

Results

Regional differences in lumbar posture and movement were found. Mean LLx posture did not correlate with ULx posture in sitting (r = 0.036, p = 0.638), but showed a moderate inverse correlation with ULx posture in usual standing (r = -0.505, p < 0.001). Regional differences in range of motion from reference postures in sitting and standing were evident. BMI accounted for regional differences found in all sitting and some standing measures. LBP was not associated with differences in regional lumbar spine angles or range of motion, with the exception of maximal backward bending range of motion (F = 5.18, p = 0.007).

Conclusion

This study supports the concept of regional differences within the lumbar spine during common postures and movements. Global lumbar spine kinematics do not reflect regional lumbar spine kinematics, which has implications for interpretation of measures of spinal posture, motion and loading. BMI influenced regional lumbar posture and movement, possibly representing adaptation due to load.