title: Can altering motions, postures, and loads provide immediate low back pain relief: a study of 4 cases investigating spine load, posture, and stability.
abstract: METHODS
  A quantitative biomechanical analysis of mechanism of pain alteration in 4 cases of low back pain.
  
  
  OBJECTIVE
  To investigate the contributions of a number of biomechanical factors associated with pain alteration.
  
  
  BACKGROUND
  Some clinicians use mechanically based manual interventions in attempt to reduce low back pain. However, the mechanism of pain alteration remains unknown.
  
  
  METHODS
  A sample was formed with 4 patients with low back pain seeking consults for pain relief. All could produce "catches" of pain with movement. Manual interventions involving coached changes in motion and muscle activation attempted to reduce pain. Electromyographic and kinematic data were collected before and after intervention. These data were input to an anatomically detailed spine model that calculated muscle force, joint compression and shear, and spine stability.
  
  
  RESULTS
  Using a clinically significant criterion of pain reduction of 2 or more, 3 of 4 subjects reduced pain immediately upon the intervention. Using a change of 10% as a criterion for biological significance for kinematic and kinetic variables, each subject demonstrated a different reaction. For example, subject 1 demonstrated increased stability, subject 2 increased mediolateral shear, subject 3 increased mediolateral shear and decreased spine flexion, and subject 4 increased stability. The pain-reducing interventions required to obtain these results were also different for each individual.
  
  
  CONCLUSIONS
  Immediate pain reduction can be achieved by altering muscle-activation and movement patterns. However, the combination for optimal success seems to be different for every individual. Pain provocation tests help to "tune" the intervention. This also suggests that patient-classification schemes may need more refinement to address this heterogeneity.
authors.affiliation: Spine Biomechanics Laboratory, Department of Kinesiology, Faculty of Applied Health Sciences, University of Waterloo, Waterloo, Ontario, Canada.
authors.forename: Dianne M
authors.initials: DM
authors.lastname: Ikeda
authors.forename: Stuart M
authors.initials: SM
authors.lastname: McGill
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D004576:Electromyography; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology / Q000628:therapy; D017116:Low Back Pain / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009068:Movement; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010147:Pain Measurement; D026741:Physical Therapy Modalities; D011187:Posture; D016059:Range of Motion, Articular; D013131:Spine / Q000503:physiopathology*; D016896:Treatment Outcome; D016474:Weight-Bearing; D055815:Young Adult