title: Effect of feedback techniques for lower back pain on gluteus maximus and oblique abdominal muscle activity and angle of pelvic rotation during the clam exercise.
abstract: OBJECTIVE
  This study was conducted in order to determine the effect of feedback tools on activities of the gluteus maximus (Gmax) and oblique abdominal muscles and the angle of pelvic rotation during clam exercise (CE).
  
  
  METHODS
  Comparative study using repeated measures.
  
  
  METHODS
  University laboratory.
  
  
  METHODS
  Sixteen subjects with lower back pain.
  
  
  METHODS
  Each subject performed the CE without feedback, the CE using a pressure biofeedback unit (CE-PBU), and the CE with palpation and visual feedback (CE-PVF). Electromyographic (EMG) activity and the angles of pelvic rotation were measured using surface EMG and a three-dimensional motion-analysis system, respectively. One-way repeated-measures ANOVA followed by the Bonferroni post hoc test were used to compare the EMG activity in each muscle as well as the angle of pelvic rotation during the CE, CE-PBU, and CE-PVF.
  
  
  RESULTS
  The results of post-hoc testing showed a significantly reduced angle of pelvic rotation and significantly more Gmax EMG activity during the CE-PVF compared with during the CE and CE-PBU.
  
  
  CONCLUSIONS
  These findings suggest that palpation and visual feedback is effective for activating the Gmax and controlling pelvic rotation during the CE in subjects with lower back pain.
authors: Department of Physical Therapy, Masan University, Changwon, Republic of Korea. Electronic address: kohpt@masan.ac.kr.
authors: Eun-Kyung
authors: EK
authors: Koh
authors: Department of Physical Therapy, College of Medical Science, Jeonju University, Republic of Korea. Electronic address: knpark@jj.ac.kr.
authors: Kyue-Nam
authors: KN
authors: Park
authors: Department of Physical Therapy, College of Tourism & Health, Kinesiopathologic Science Institute, Joongbu University, Geumsan, Republic of Korea. Electronic address: ptsports@joongbu.ac.kr.
authors: Do-Young
authors: DY
authors: Jung
mesh_terms: D000009:Abdominal Muscles / Q000503:physiopathology*; D001676:Biofeedback, Psychology; D002081:Buttocks / Q000503:physiopathology*; D004185:Disability Evaluation; D004576:Electromyography; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology* / Q000534:rehabilitation; D008297:Male; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010388:Pelvis / Q000503:physiopathology*; D012399:Rotation; D055815:Young Adult
keywords: Clam exercise; Gluteus maximus; Lower back pain; Pelvic rotation