Background: Alterations in postural sway have been reported in persons with LBP, and it is hypothesized that this might be due to disturbed lumbar proprioception. However, there is today no accepted clinical test to assess lumbar proprioception, especially when it comes to evaluation of the unconscious part of proprioception. The purpose of this study was to validate a new clinical test of lumbar proprioception in persons with mechanical nociceptive low back pain (LBP).

Aims: To preliminary validate a new test for clinical assessment of postural sway with lumbar spine in torsional position, designed to assess the unconscious part of lumbar proprioception.

Design: Cross-sectional study.

Method: Postural sway was evaluated on a Wii Balance Board (WBB) and with software WBB vibration program Julia Treleaven 1.3. 30 individuals with LBP and 28 controls participated. The outcome variables of center of pressure (COP) were path velocity, mediolateral (ML) amplitude and anteroposterior (AP) amplitude.

Results: No statistically significant difference was found between groups regarding any of the variables of postural sway (path velocity, ML and AP amplitude) in neutral, torsion right and torsion left. Statistically significant difference was found in torsion difference left AP amplitude (p=0.033), but not for any other of the variables in torsion difference left and torsion difference right. There was a small, non-significant correlation between index score of pain on movement questionnaire (POM) and postural sway in neutral, torsion right and left.

Conclusion: Participants with predominantly mechanical nociceptive LBP present with similar postural sway variables as controls. Postural sway with lumbar spine in a torsioned position could not identify those with LBP from controls. We suggest further evaluation of the lumbar torsion test when it is ascertained for that the torsion maneuver is biased to and retained in the lumbar spine.