title: Measuring lumbar reposition accuracy in patients with unspecific low back pain: systematic review and meta-analysis.
abstract: METHODS
  Systematic review and meta-analysis.
  
  
  OBJECTIVE
  To evaluate if patients with nonspecific chronic low back pain (NSCLBP) show a greater lumbar reposition error (RE) than healthy controls.
  
  
  BACKGROUND
  Studies on lumbar RE in patients with NSCLBP present conflicting results.
  
  
  METHODS
  A systematic review and meta-analysis of the available literature were performed to evaluate differences in RE between patients with NSCLBP and healthy controls. Data on absolute error, constant error (CE), and variable error were extracted and effect sizes (ESs) were calculated. For the CE flexion pattern and active extension pattern, subgroups of patients with NSCLBP were analyzed. Results of homogeneous studies were pooled. Measurement protocols and study outcomes were compared. The quality of reporting and the authors' appraisal of risk of bias were investigated.
  
  
  RESULTS
  The original search revealed 178 records of which 13 fulfilled the inclusion criteria. The majority of studies showed that patients with NSCLBP produced a significantly larger absolute error (ES, 0.81; 95% confidence interval [95% CI], 0.13-1.49) and variable error (ES, 0.57; 95% CI, 0.05-1.09) compared with controls. CE is direction specific in flexion and active extension pattern subgroups of patients with NSCLBP (ES, 0.39; 95% CI, -1.09 to 0.3) and ES, 0.18; 95% CI, -0.3 to 0.65, respectively). The quality of reporting and the authors' appraisal of risk of bias varied considerably. The applied test procedures and instrumentation varied between the studies, which hampered the comparability of studies.
  
  
  CONCLUSIONS
  Although patients with NSCLBP seemed to produce a larger lumbar RE compared with healthy controls, study limitations render firm conclusions unsafe. Future studies should pay closer attention to power, precision, and reliability of the measurement approach, definition of outcome measures, and patient selection. We recommend a large, well-powered, prospective randomized control study that uses a standardized measurement approach and definitions for absolute error, CE, and variable error to address the hypothesis that proprioception may be impaired with CLBP.
authors.affiliation: *Department of Physiotherapy, Zurich University of Applied Sciences (ZHAW), Winterthur, Switzerland; and †Department of Physical and Rehabilitation Medicine, Tampere University Hospital, Tampere, Finland.
authors.forename: Anne-Kathrin
authors.initials: AK
authors.lastname: Rausch Osthoff
authors.forename: Markus J
authors.initials: MJ
authors.lastname: Ernst
authors.forename: Fabian M
authors.initials: FM
authors.lastname: Rast
authors.forename: Danica
authors.initials: D
authors.lastname: Mauz
authors.forename: Eveline S
authors.initials: ES
authors.lastname: Graf
authors.forename: Jan
authors.initials: J
authors.lastname: Kool
authors.forename: Christoph M
authors.initials: CM
authors.lastname: Bauer
mesh_terms: D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology*; D008159:Lumbar Vertebrae / Q000503:physiopathology*; D008161:Lumbosacral Region / Q000503:physiopathology*; D010147:Pain Measurement; D011187:Posture / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*