title: Is there a subgroup of patients with low back pain likely to benefit from mechanical traction? Results of a randomized clinical trial and subgrouping analysis.
abstract: METHODS
  Randomized Clinical Trial.
  
  
  OBJECTIVE
  To identify a subgroup of patients with low back pain who are likely to respond favorably to an intervention including mechanical traction.
  
  
  BACKGROUND
  Previous research has failed to find evidence supporting traction for patients with low back pain. Previous studies have used heterogeneous samples, although clinical experts tend to recommend traction for a more limited subgroup of patients with low back pain.
  
  
  METHODS
  Sixty-four subjects (mean age 41.1 year, 56.3% female) with low back and leg pain and signs of nerve root compression were randomized to receive a 6-week extension-oriented intervention with or without mechanical traction during the first 2 weeks. Between-group comparisons were conducted for changes in pain, disability, and fear-avoidance beliefs. Baseline variables were explored for potential as subgrouping criteria defining a subgroup of subjects likely to benefit from traction.
  
  
  RESULTS
  The group receiving traction showed greater improvements in disability (adjusted mean difference in Oswestry change 7.2 points) and fear-avoidance beliefs (adjusted mean difference in FABQPA change 2.6 points) after 2 weeks. There were no between-group differences after 6 weeks. Two baseline variables were associated with greater improvements with traction treatment; peripheralization with extension movements and a crossed straight leg raise.
  
  
  CONCLUSIONS
  A subgroup of patients likely to benefit from mechanical traction may exist. The results of this study suggest this subgroup is characterized by the presence of leg symptoms, signs of nerve root compression, and either peripheralization with extension movements or a crossed straight leg raise. Further research is needed to validate this finding.
authors: Intermountain Healthcare, Salt Lake City, UT, USA. Julie.fritz@hsc.utah.edu
authors: Julie M
authors: JM
authors: Fritz
authors: Weston
authors: W
authors: Lindsay
authors: James W
authors: JW
authors: Matheson
authors: Gerard P
authors: GP
authors: Brennan
authors: Stephen J
authors: SJ
authors: Hunter
authors: Steve D
authors: SD
authors: Moffit
authors: Aaron
authors: A
authors: Swalberg
authors: Brian
authors: B
authors: Rodriquez
mesh_terms: D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D017116:Low Back Pain / Q000145:classification* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D016037:Single-Blind Method; D014143:Traction / Q000379:methods*