title: The relationship between spasticity and muscle volume of the knee extensors in children with cerebral palsy.
abstract: OBJECTIVE
  The purpose of this study was to examine the relationship between spasticity and muscle volume in children with cerebral palsy (CP), using isokinetic dynamometry and magnetic resonance imaging.
  
  
  METHODS
  A retrospective sample of 8 children with diplegic CP was analyzed. One set of 10 passive knee flexion movements was completed at a velocity of 180° per second with concurrent surface electromyography of the medial hamstrings (MH) and vastus lateralis (VL) to assess knee extensor spasticity. Magnetic resonance imaging was used to measure maximum cross-sectional area and muscle volume of the quadriceps femoris.
  
  
  RESULTS
  The quadriceps femoris muscle volume was positively correlated with MH reflex activity, VL reflex activity, MH/VL co-contraction, and peak knee extensor passive torque (P < .05).
  
  
  CONCLUSIONS
  The present findings suggest that higher levels of knee extensor muscle spasticity are associated with greater quadriceps muscle volume in children with spastic diplegic CP.
authors.affiliation: Institute for Physical Therapy Education, Widener University, Chester, Pennsylvania, USA. srpierce@mail.widener.edu
authors.forename: Samuel R
authors.initials: SR
authors.lastname: Pierce
authors.forename: Laura A
authors.initials: LA
authors.lastname: Prosser
authors.forename: Samuel C K
authors.initials: SC
authors.lastname: Lee
authors.forename: Richard T
authors.initials: RT
authors.lastname: Lauer
mesh_terms: D000293:Adolescent; D002547:Cerebral Palsy / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D002648:Child; D005260:Female; D006801:Humans; D007717:Knee / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D008297:Male; D009128:Muscle Spasticity / Q000175:diagnosis / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology*; D053580:Muscle Strength / Q000502:physiology*; D053581:Muscle Strength Dynamometer; D018482:Muscle, Skeletal / Q000473:pathology*; D009929:Organ Size; D016059:Range of Motion, Articular / Q000502:physiology; D012018:Reflex / Q000502:physiology; D012189:Retrospective Studies