title: Peg Restrained Intrinsic Muscle Evaluator (PRIME): development, reliability, and normative values of a device to quantify intrinsic hand muscle strength in children.
abstract: OBJECTIVE
  There is a need for objective measures of pediatric intrinsic hand muscle strength as the current standard, the manual muscle test, lacks sensitivity to clinically important changes in muscle strength. We report the development, reliability, and normative values of the Peg Restrained Intrinsic Muscle Evaluator (PRIME), a device that quantifies intrinsic hand muscle strength.
  
  
  METHODS
  Typically developing children, ages 4 to 16 years (n = 119), established normative values of intrinsic strength for thumb palmar abduction, thumb opposition, and index and small finger abduction. A subset of 30 children (15 boys, 15 girls), ages 7 to 16 years, determined inter-rater and intra-rater reliability. We calculated mean, standard deviation, intraclass correlation coefficients, and smallest detectable differences.
  
  
  RESULTS
  Normative results indicate that gender and age were significant predictors of strength. Although the dominant hand generated higher strength measurements on average, differences were not statistically significant. Mean index and small finger abduction strength was significantly lower than thumb abduction and opposition in both genders. Intraclass correlation coefficients ranged from 0.85 to 0.94 for inter-rater reliability and 0.88 to 0.98 for intra-rater reliability. Bland-Altman plots showed an even distribution across the zero line.
  
  
  CONCLUSIONS
  The PRIME device is a reliable tool for the quantification of intrinsic hand muscle strength in children. Age-specific and gender-specific normative values in typically developing children can serve as a future resource for clinicians treating pediatric hand or neuromuscular conditions.
authors: Department of Bioengineering, Rice University, Houston, TX, USA.
authors: Shuai
authors: S
authors: Xu
authors: Adrianne M
authors: AM
authors: Morse
authors: Barbara
authors: B
authors: Lacy
authors: L Scott
authors: LS
authors: Baggett
authors: Gloria R
authors: GR
authors: Gogola
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002657:Child Development / Q000502:physiology; D004867:Equipment Design; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D053581:Muscle Strength Dynamometer; D018482:Muscle, Skeletal / Q000502:physiology; D012016:Reference Values; D015203:Reproducibility of Results; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D012737:Sex Factors