title: Muscle strength does not explain standing ability in children with bilateral spastic cerebral palsy: a cross sectional descriptive study.
abstract: BACKGROUND
  In bilateral cerebral palsy (CP) muscle strength is considered important for development of gross motor functions, but its influence on standing ability has not been explored. Our aims were to examine muscle strength with respect to the ability to stand with (SwS) or without (SwoS) hand support, asymmetrical weight bearing (WB), and whether the ability to produce strength was influenced by different seated conditions.
  
  
  METHODS
  In this cross sectional descriptive study standing posture was recorded with 3D motion analysis, and muscle strength was measured with a hand-held dynamometer, in 25 children with bilateral CP, GMFCS levels II-III, SwS (n = 14, median age 11.4 years), or SwoS, (n = 11, median age 11.4 years). Strength measurements were taken in the hip flexors, knee extensors, dorsiflexors and plantarflexors, in two seated conditions; a chair with arm- and backrests, and a stool.
  
  
  RESULTS
  Compared to SwoS, children SwS stood with a more flexed posture, but presented with equal strength in the hip flexors, dorsiflexors and plantarflexors, and with somewhat more strength in the knee extensors. Despite asymmetric WB during standing, both limbs were equally strong in the two groups. No differences in strength were measured between the two seated conditions.
  
  
  CONCLUSIONS
  Despite challenges measuring muscle strength in CP, the lower limb muscle strength cannot be considered an explanatory factor for variations in standing in this group of children with bilateral CP. The findings rather strengthen our hypothesis that deficits in the sensory systems could be as determinant for standing as muscle weakness in children with bilateral spastic CP.
authors.affiliation: Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden. cecilia.lidbeck@ki.se.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Lidbeck
authors.affiliation: Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden. kristina.tedroff@ki.se.
authors.forename: Kristina
authors.initials: K
authors.lastname: Tedroff
authors.affiliation: Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden. asa.bartonek@ki.se.
authors.forename: Åsa
authors.initials: Å
authors.lastname: Bartonek
mesh_terms: D000293:Adolescent; D002547:Cerebral Palsy / Q000503:physiopathology*; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000503:physiopathology*; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D011187:Posture / Q000502:physiology*