title: Physical function and mobility in children with congenital myotonic dystrophy.
abstract: Congenital myotonic dystrophy (CDM) occurs when symptoms of myotonic dystrophy present at birth. In this study we evaluated the relationship between physical function, muscle mass, and age to provide an assessment of the disease and help prepare for therapeutic trials.
  
  
  
  CDM participants performed timed functional tests (TFTs), the first 2 minutes of 6-minute walk tests (2/6MWTs), and myometry tests, and also performed dual-energy X-ray absorption (DEXA) scans. Healthy controls (HCs) performed TFTs, 6MWTs, and myometry.
  
  
  
  Thirty-seven children with CDM and 27 HCs (age range 3-13 years) participated in the study. There were significant differences in the 10-meter walk (11.3 seconds in CDM vs. 6.8 seconds in HC) and 2MWT (91 meters in CDM vs. 193 meters in HCs). DEXA lean mass of the right arm correlated with grip strength (r = 0.91), and lean mass of the right leg correlated with 6MWT (r = 0.62).
  
  
  
  Children with CDM have significant limitations in strength and mobility. The tests performed were reliable, and lean muscle mass may serve as a useful biomarker. Muscle Nerve 56: 224-229, 2017.
authors.affiliation: Eccles Institute of Human Genetics, Department of Neurology, University of Utah School of Medicine, 15N 2030 East, Salt Lake City, Utah, 84112, USA.
authors.forename: Evan M
authors.initials: EM
authors.lastname: Pucillo
authors.affiliation: Eccles Institute of Human Genetics, Department of Neurology, University of Utah School of Medicine, 15N 2030 East, Salt Lake City, Utah, 84112, USA.
authors.forename: Deanna L
authors.initials: DL
authors.lastname: Dibella
authors.affiliation: Department of Orthopedics, University of Utah, Salt Lake City, Utah, USA.|Division of Public Health, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Man
authors.initials: M
authors.lastname: Hung
authors.affiliation: Department of Orthopedics, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Jerry
authors.initials: J
authors.lastname: Bounsanga
authors.affiliation: Eccles Institute of Human Genetics, Department of Neurology, University of Utah School of Medicine, 15N 2030 East, Salt Lake City, Utah, 84112, USA.
authors.forename: Becky
authors.initials: B
authors.lastname: Crockett
authors.affiliation: Eccles Institute of Human Genetics, Department of Neurology, University of Utah School of Medicine, 15N 2030 East, Salt Lake City, Utah, 84112, USA.
authors.forename: Melissa
authors.initials: M
authors.lastname: Dixon
authors.affiliation: Department of Pediatrics, University of Utah, Salt Lake City, Utah, USA.
authors.forename: Russell J
authors.initials: RJ
authors.lastname: Butterfield
authors.affiliation: Department of Pediatrics, Clinical Neurological Sciences and Epidemiology, Western University, London, Ontario, Canada.
authors.forename: Craig
authors.initials: C
authors.lastname: Campbell
authors.affiliation: Eccles Institute of Human Genetics, Department of Neurology, University of Utah School of Medicine, 15N 2030 East, Salt Lake City, Utah, 84112, USA.
authors.forename: Nicholas E
authors.initials: NE
authors.lastname: Johnson
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D009223:Myotonic Dystrophy / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D018709:Statistics, Nonparametric; D013997:Time Factors; D016138:Walking / Q000502:physiology*
keywords: 6-minute walk test; congenital myotonic dystrophy; functional outcomes; myotonic dystrophy, mobility measures