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Manual Muscle Testing: A Method of Measuring Extremity Muscle Strength Applied to Critically Ill Patients
09:44

Manual Muscle Testing: A Method of Measuring Extremity Muscle Strength Applied to Critically Ill Patients

Published on: April 12, 2011

Objective evaluation of muscle strength in infants with hypotonia and muscle weakness

Linda Reus1, Leo A van Vlimmeren, J Bart Staal

  • 1Radboud University Nijmegen Medical Centre, Department of Rehabilitation, Pediatric Physical Therapy, Nijmegen, The Netherlands. l.reus@reval.umcn.nl

Research in Developmental Disabilities
|February 6, 2013
PubMed

Insights

Objective infant muscle strength measurement is now possible. This study provides reference values and confirms significantly decreased muscle strength in infants with Prader-Willi Syndrome (PWS), correlating with motor delay.

Area of Science:

  • Pediatric Neurology
  • Developmental Pediatrics
  • Clinical Measurement

Background:

  • Objective muscle strength assessment is crucial for evaluating infants with motor delay, hypotonia, or weakness.
  • Lack of standardized measurement methods and reference values hinders accurate clinical assessment in infants.

Purpose of the Study:

  • To develop and validate a reliable method for objectively measuring muscle strength in infants.
  • To establish normal reference values for infant muscle strength.
  • To assess muscle strength in infants with Prader-Willi Syndrome (PWS) and its correlation with motor development.

Main Methods:

  • A novel method for measuring infant muscle strength was developed and tested.
  • 81 typically developing infants (6-36 months) and 17 infants with PWS (24 months) participated.
  • Inter-rater reliability and convergent validity (correlation with age, height, weight) were assessed.

Main Results:

  • The measurement method demonstrated good inter-rater reliability (ICC=.84) and strong convergent validity (r=.79-.85).
  • A regression model predicted 73% of muscle strength variance based on age, height, and weight.
  • Infants with PWS exhibited significantly reduced muscle strength, with greater weakness correlating with more severe motor delay (r=.75).

Conclusions:

  • A reliable and valid method for objective infant muscle strength measurement has been established.
  • This method provides essential reference data for clinical evaluation.
  • Significantly decreased muscle strength and its association with motor delay in infants with PWS were confirmed.

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