title: Influence of low back pain status on pelvis-trunk coordination during walking and running.
abstract: METHODS
  Two-way repeated-measures analysis of variance.
  
  
  OBJECTIVE
  To assess pelvis and trunk three-dimensional segmental excursions and coordination differences during walking and running between runners with low back pain (LBP), runners with resolved LBP, and a control group with no history of LBP.
  
  
  BACKGROUND
  Studies have documented differences in pelvis and trunk coordination between those with moderate to severe LBP during walking. Few studies document pelvis and trunk mechanics in those with low to moderate LBP and individuals who recover from LBP even though these individuals comprise 80% of LBP cases and are at increased risk for re-injury.
  
  
  METHODS
  Recreational runners walked and ran on a treadmill at speeds including 0.8 to 3.8 m/s at 0.5 m/s increments. Pelvis and trunk kinematic data were collected during the last 20 s of each stage. Coordination analysis quantified the portion of gait cycle each group spent in trunk only motion, pelvis-only motion, in-phase, and antiphase relationships.
  
  
  RESULTS
  During walking, the LBP group spent more of the gait cycle in-phase in the frontal plane (P = 0.030). During running, the LBP group showed greater pelvis axial rotation than the control group (P = 0.014) and spent more of the gait cycle in-phase in the transverse plane (P = 0.019). Also during running, the LBP (P = 0.035) and the resolved LBP (P = 0.037) groups demonstrated reduced antiphase coordination compared to controls.
  
  
  CONCLUSIONS
  Coordination analysis demonstrates a reduction in relative motion between the pelvis and trunk despite low disability levels in our LBP group and no pain in our group with a history of LBP.
authors.affiliation: Department of Kinesiology, University of Massachusetts-Amherst, MA, USA. joseph.seay@us.army.mil
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Seay
authors.forename: Richard E A
authors.initials: RE
authors.lastname: Van Emmerik
authors.forename: Joseph
authors.initials: J
authors.lastname: Hamill
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001696:Biomechanical Phenomena; D005080:Exercise Test; D005260:Female; D005684:Gait / Q000502:physiology; D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology; D010147:Pain Measurement; D010388:Pelvis / Q000503:physiopathology*; D004856:Postural Balance / Q000502:physiology; D016059:Range of Motion, Articular; D012420:Running / Q000502:physiology*; D013131:Spine / Q000503:physiopathology; D016138:Walking / Q000502:physiology*; D055815:Young Adult