Assessment of Abdominal Muscle Function During a Simulated Unilateral Weightbearing Task Using Ultra

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Assessment of Abdominal Muscle Function During a
Simulated Unilateral Weight-bearing Task Using
Ultrasound Imaging

• Hides, Wong, Wilson, Belavy Richardson, 2007

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SUMMARY

• Biomechanical model (Snijders, 1993)
• Tranversely oriented lumbopelvic mms stabilize
  joints of the pelvis for WBing
• These mms have been shown to contract by
  increasing in thickness of cross-section and by
  lateral sliding of the anterior portion of
  fascia.

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SUMMARY

• Cross-sectional design, pilot study on 19 healthy
  subjects
• Results
• Significant increase in TrA and IO mms thickness
  before and after WBing.
• Significant lateral mvmt of anterior abd fascia
  with WBing
• Both of these changes occurred symmetrically

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SUMMARY

• Conclusion
• Symmetrical activation of transversely oriented
  lumbopelvic mms occurs in healthy subjects in
  response to a unilateral functional WBing task.
• Overall impression mediocre study

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CRITIQUE

• JOSPT
• Title and Abstract Brief, informative and
  specific
• Intro Solid theoretical context based on the
  biological model and appropriate and
  comprehensive references.
• The established a sound rationale for their
  methods based on the literature.

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CRITIQUE

• Intro Exploratory research to measure changes
  across a whole group.
• No hypothesis explicitly stated but inferred from
  lit review
• Purpose clearly stated
• Never discuss question of symmetry in
  introduction

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CRITIQUE

• Subjects 19 healthy subjects, ages 15-25
• Small
• Healthy
• Sex, age, height exclusion criteria listed
• No description of selection process or from what
  population

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CRITIQUE

• Design
• Cross-sectional observations of different age or
  developmental groups at one point in time,
  providing basis for inferring trends over time.
• One measurement taken.
• described changes in muscles with specific task
  in only one group.

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CRITIQUE

• Instrumentation
• Described instruments some detail
• Description of each instrument
• Provided name and address of manufacturer
• However, we would like to know
• Are these standard pieces of equipment?
• Commercially available?

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CRITIQUE

• Instrumentation
• Reliability and Validity
• Provided some validity for Ultrasound
• In terms of comparing it to other equipment
• However, we would like to know
• Reliability and validity for each instrument
• Intrarater and Interrater reliability
• Reliability of instruments for specific
  population

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CRITIQUE

• Procedures
• No operational definitions of independent and
  dependent variables
• Threats to internal validity were not discussed

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CRITIQUE

• Procedures
• Patient performs single leg stance while laying
  supine on sliding board
• TA and IO observed and measured using Ultrasound
• The data collection procedures were described
• However there were some questions
• Who recorded the data (researcher, therapist?)
• How was the application of force and breathing
  synchronized?

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CRITIQUE

• Procedures
• No operational definitions of independent and
  dependent variables
• Threats to internal validity were not discussed

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CRTIQUE

• Data Analysis
• Two ANOVA statistical tests
• 1st measure thickness of the muscles and symmetry
• 2nd measured amount of slide in muscles
• The appropriate ANOVA statistical test used
• Alpha of less than .05 was used in statistical
  analysis

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CRITIQUE

• Results
• The results of the experiment were clear
• The table is clear, concise and accurate
• The hypothesis was not addressed
• Results statistically significant
• No discussion on how anthropometric covariates
  effected results

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CRITIQUE

• Discussion
• Interpreted results
• initial evidence that the lumbopelvic corset is
  automatically formed
• Bilateral and symmetrical contraction of TA and
  IO muscles

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CRITIQUE

• Discussion
• Results are supported by the literature
• Good discussion on how results are clinically
  relevant
• Good discussion on the limitations of the pilot
  study
• Would have liked to have seen
• Alternative explanations for obtained findings

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CRITIQUE

• Conclusion
• Gave a nice summery of the how the results fit
  into the biomechanical model that was discussed
  in the introduction.
• Study has clinical relevance

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CRITIQUE

• Overall Impression
• Good start, no follow through
• No discussion of reliability or validity
• No lead up to significance of symmetry in intro
• No description of results of arthropometric
  co-variants