title: Evidence of altered lumbopelvic muscle recruitment in the presence of sacroiliac joint pain.
abstract: METHODS
  Cross-sectional study of electromyographic onsets of trunk and hip muscles in subjects with a clinical diagnosis of sacroiliac joint pain and matched control subjects.
  
  
  OBJECTIVE
  To determine whether muscle activation of the supporting leg was different between control subjects and subjects with sacroiliac joint pain during hip flexion in standing.
  
  
  BACKGROUND
  Activation of the trunk and gluteal muscles stabilize the pelvis for load transference; however, the temporal pattern of muscle activation and the effect of pelvic pain on temporal parameters has not been investigated.
  
  
  METHODS
  Fourteen men with a clinical diagnosis of sacroiliac joint pain and healthy age-matched control subjects were studied. Surface electromyographic activity was recorded from seven trunk and hip muscles of the supporting leg during hip flexion in standing. Onset of muscle activity relative to initiation of the task was compared between groups and between limbs.
  
  
  RESULTS
  The onset of obliquus internus abdominis (OI) and multifidus occurred before initiation of weight transfer in the control subjects. The onset of obliquus internus abdominis, multifidus, and gluteus maximus was delayed on the symptomatic side in subjects with sacroiliac joint pain compared with control subjects, and the onset of biceps femoris electromyographic activity was earlier. In addition, electromyographic onsets were different between the symptomatic and asymptomatic sides in subjects with sacroiliac joint pain.
  
  
  CONCLUSIONS
  The delayed onset of obliquus internus abdominis, multifidus, and gluteus maximus electromyographic activity of the supporting leg during hip flexion, in subjects with sacroiliac joint pain, suggests an alteration in the strategy for lumbopelvic stabilization that may disrupt load transference through the pelvis.
authors.affiliation: School of Exercise and Sport Science, University of Sydney, Australia.
authors.forename: Barbara
authors.initials: B
authors.lastname: Hungerford
authors.forename: Wendy
authors.initials: W
authors.lastname: Gilleard
authors.forename: Paul
authors.initials: P
authors.lastname: Hodges
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004576:Electromyography; D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000503:physiopathology*; D017773:Pelvic Floor; D017699:Pelvic Pain / Q000503:physiopathology; D012446:Sacroiliac Joint / Q000503:physiopathology*