title: The natural history of cardiac and pulmonary function decline in patients with duchenne muscular dystrophy.
abstract: METHODS
  Retrospective review of scoliosis progression, pulmonary and cardiac function in a series of patients with Duchenne Muscular Dystrophy (DMD).
  
  
  OBJECTIVE
  To determine whether operative treatment of scoliosis decreases the rate of pulmonary function loss in patients with DMD.
  
  
  BACKGROUND
  It is generally accepted that surgical intervention should be undertaken in DMD scoliosis once curve sizes reach 35° to allow intervention before critical respiratory decline has occurred. There are conflicting reports, however, regarding the effect of scoliosis stabilization on the rate of pulmonary function decline when compared to nonoperative cohorts.
  
  
  METHODS
  We reviewed spinal radiographs, echocardiograms, and spirometry, hospital, and operative records of all patients seen at our tertiary referral center from July 1, 1992 to June 1, 2007. Data were recorded to Microsoft Excel (Microsoft, Redmond, WA) and analyzed with SAS (SAS Institute, Cary, NC) and R statistical processing software (www.r-project.org).
  
  
  RESULTS
  The percent predicted forced vital capacity (PPFVC) decreased 5% per year before operation. The mean PPFVC was 54% (SD = 21%) before operation with a mean postoperative PPFVC of 43% (SD = 14%). Surgical treatment was associated with a 12% decline in PPFVC independent of other treatment variables. PPFVC after operation declined at a rate of 1% per year and while this rate was lower, it was not significantly different than the rate of decline present before operation (P = 0.18). Cardiac function as measured by left ventricular fractional shortening declined at a rate of 1% per year with most individuals exhibiting a left ventricular fractional shortening rate of more than 30 before operation.
  
  
  CONCLUSIONS
  Operative treatment of scoliosis in DMD using the Luque Galveston method was associated with a reduction of forced vital capacity related to operation. The rate of pulmonary function decline after operation was not significantly reduced when compared with the rate of preoperative forced vital capacity decline.
authors.affiliation: Department of Orthopedics, University of California, Davis, CA, USA. Rolando.Roberto@ucdmc.ucdavis.edu
authors.forename: Rolando
authors.initials: R
authors.lastname: Roberto
authors.forename: Anto
authors.initials: A
authors.lastname: Fritz
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Hagar
authors.forename: Braden
authors.initials: B
authors.lastname: Boice
authors.forename: Andrew
authors.initials: A
authors.lastname: Skalsky
authors.forename: Hosun
authors.initials: H
authors.lastname: Hwang
authors.forename: Laurel
authors.initials: L
authors.lastname: Beckett
authors.forename: Craig
authors.initials: C
authors.lastname: McDonald
authors.forename: Munish
authors.initials: M
authors.lastname: Gupta
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D006321:Heart / Q000503:physiopathology*; D006801:Humans; D008168:Lung / Q000503:physiopathology*; D008297:Male; D020388:Muscular Dystrophy, Duchenne / Q000150:complications*; D012189:Retrospective Studies; D012600:Scoliosis / Q000150:complications / Q000503:physiopathology / Q000601:surgery*; D013131:Spine / Q000503:physiopathology / Q000601:surgery; D016896:Treatment Outcome; D016277:Ventricular Function, Left; D014797:Vital Capacity; D055815:Young Adult