title: Relationship between ultrasonography and electromyography measurement of abdominal muscles when activated with and without pelvis floor muscles contraction.
abstract: OBJECTIVE
  The importance of the abdominal musculature in spine stability, has promoted the development of a variety of studies. Ultrasound imaging (UI) is a valuable tool which, when applied appropriately, has the potential to provide significant insight into abdominal muscle contraction. Limited studies have been taken place regarding the relationship between ultrasound measures of muscle thickening and electromyography (EMG) measures of activation. Inconsistent results, however, have been reported. Based on previous studies association between abdominal muscle activation and thickening may be affected by contraction level. The aims of this study were to measure the relationship between abdominal muscle thickness and abdominal muscles amplitude in different levels of abdominal muscles contraction.
  
  
  METHODS
  The research was carried on with a convenience sampling at the Physical Therapy Department of University of Social Welfare and Rehabilitation Sciences. Thirty healthy participants volunteered for this study. Muscle thickness right transversus abdominis (TrA) and obliqus internus (OI) muscles in abdominal hallowing maneuvers with and without pelvic floor muscle (PFM) contraction has been measured. Additionally, surface EMG of the right TrA/IO muscles was recorded. A hardware electrical part that acts as trigger system was used to record the activities of abdominal muscles in UI and EMG synchronously. Thickness change, normalized thickness and maximum amplitude abdominal muscles were used for statistical analysis.
  
  
  RESULTS
  Correlations between the thickness change and amplitude measures were -0.03 -- 0.38 for TrA/IO. The Correlations between the normalized thickness and amplitude measures were -0.04--0.26 for TrA/IO.
  
  
  CONCLUSIONS
  There is not clear relationship between increases in abdominal muscle activation and corresponding measures of thickening during abdominal muscle contraction. Changes in thickness of deep abdominal muscle cannot be used to indicate changes in the electrical activity in this muscle.
authors: Department of Physical Therapy, Faculty of Rehabilitation Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran2 Department of Physical Therapy, University of Social Welfar and Rehabilitation Sciences, Evin, Tehran, Iran - nahidta2431@gmail.com.
authors: N
authors: N
authors: Tahan
authors: A M
authors: AM
authors: Arab
authors: P
authors: P
authors: Arzani
authors: F
authors: F
authors: Rahimi
mesh_terms: D000009:Abdominal Muscles / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000502:physiology*; D000293:Adolescent; D000328:Adult; D004576:Electromyography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D017773:Pelvic Floor / Q000000981:diagnostic imaging / Q000502:physiology; D014463:Ultrasonography; D055815:Young Adult