Design:  A cross-sectional observational study

Background: Low back pain (LBP) is a common cause for disability and a reported prevalence of over 70% in industrialized countries with high risk of recurrent episodes or development of chronic low back pain. Increasing knowledge about LBP-mechanisms and treatments are a priority.

Objective: This study evaluated joint positioning sense (JPS) CE, VE and AE differences between CLBP-individuals and healthy-controls using a new laser-pointer device and test it for its discriminating ability as a preliminary validation

Methods: 41 individuals with mechanical LBP and 41 healthy-controls were measured for lumbar spine repositioning error using a new low cost laser-pointer attached on L1 and S1 targeting a gitter. Active repositioning to a criterion position was tested in flexion, extension, right and left rotation in seated position. Constant error (CE), Variable error (VE) and Absolute error (AE) were calculated from the measurements. Group differences was analyzed with one-way analysis of covariance (ANCOVA) model

Results: The mean group differences of all 24 CE, VE and AE outcome scores were small, ranging from 0.0°-1.1°. Only one score was significantly different, S1 CE flexion score was 0.3° higher (p= 0.01) in the mechanical LBP-group after the analysis.

Conclusion: These findings could not confirm that mechanical chronic LBP- individuals had JPS impairment using a new low cost laser-pointer for measurement compared with healthy-controls. The new laser-pointer method testing JPS might not be sensitive enough or relevant to detect JPS impairment.