title: The time to and determinants of first fractures in boys with Duchenne muscular dystrophy.
abstract: Boys with vertebral fractures (VF) identified through routine spine radiographs had milder, less symptomatic, and fewer VF compared to those diagnosed with VF following consultation for back pain. Spontaneous (i.e., medication-unassisted) reshaping of fractured vertebral bodies was absent. Long bone fractures were present even before Duchenne muscular dystrophy (DMD) diagnosis in some boys.
  
  
  
  The objective of the study was to determine the time to and characteristics of first fractures in Duchenne muscular dystrophy.
  
  
  
  This study was a retrospective longitudinal study of 30 boys with DMD <18 years. Boys were classified into four groups according to their first fracture: those with VF identified on routine lateral spine radiographs, those with VF diagnosed following consultation for back pain, those with long bone fractures, and those without fractures.
  
  
  
  Compared to boys diagnosed with VF as their initial fracture following consultation for back pain, those with VF surveillance radiographs had shorter durations of glucocorticoid (GC) therapy at the time of VF diagnosis (median 1.6 versus 5.3 years, p < 0.01), higher areal (mean ± standard deviation -1.4 ± 0.7 versus -3.1 ± 0.8, p = 0.01), and volumetric (-0.3 ± 0.5 versus -2.6 ± 0.8, p < 0.01) lumbar spine bone mineral density Z-scores, as well as fewer VF (median 1.4 versus 5.2 per person, p < 0.01) and a lower median spinal deformity index (median 1.5 versus 9.5, p < 0.01). Vertebral body reshaping following VF was not observed. Ten boys sustained a long bone fracture as their first fracture at a mean age of 8.9 ± 4.0 years; four of these boys later sustained a total of 27 incident VF.
  
  
  
  Routine lateral spine radiographs led to detection of VF in their earlier stages, vertebral body reshaping following VF was absent, and VF were frequent after the first long bone fracture. These results support the inclusion of a lateral spine radiograph starting at the time of GC initiation as part of routine bone health monitoring in DMD.
authors: Pediatric Bone Health Clinical Research Program, Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada.|School of Epidemiology, Public Health and Preventive Medicine, University of Ottawa, Ottawa, ON, Canada.
authors: J
authors: J
authors: Ma
authors: Department of Pediatrics, and Division of Neurology, Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, ON, Canada.
authors: H J
authors: HJ
authors: McMillan
authors: Department of Pediatric Endocrinology, Karadeniz Technical University School of Medicine, Trabzon, Turkey.
authors: G
authors: G
authors: Karagüzel
authors: Pediatric Bone Health Clinical Research Program, Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada.
authors: C
authors: C
authors: Goodin
authors: Pediatric Bone Health Clinical Research Program, Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada.
authors: J
authors: J
authors: Wasson
authors: Department of Medical Imaging, Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, ON, Canada.
authors: M A
authors: MA
authors: Matzinger
authors: Pediatric Bone Health Clinical Research Program, Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada.
authors: P
authors: P
authors: DesClouds
authors: Pediatric Bone Health Clinical Research Program, Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada.
authors: D
authors: D
authors: Cram
authors: Pediatric Bone Health Clinical Research Program, Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada.
authors: M
authors: M
authors: Page
authors: Pediatric Bone Health Clinical Research Program, Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada.
authors: V N
authors: VN
authors: Konji
authors: Department of Radiology, University of British Columbia, Vancouver, BC, Canada.
authors: B
authors: B
authors: Lentle
authors: Pediatric Bone Health Clinical Research Program, Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON, Canada. lward@cheo.on.ca.|Department of Pediatrics, and Division of Endocrinology and Metabolism, Children's Hospital of Eastern Ontario, University of Ottawa, 401 Smyth Rd, Ottawa, ON, K1H 8L1, Canada. lward@cheo.on.ca.
authors: L M
authors: LM
authors: Ward
mesh_terms: D000293:Adolescent; D015519:Bone Density / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D004334:Drug Administration Schedule; D005938:Glucocorticoids / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D006801:Humans; D008137:Longitudinal Studies; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000503:physiopathology; D008297:Male; D020388:Muscular Dystrophy, Duchenne / Q000150:complications* / Q000503:physiopathology; D058866:Osteoporotic Fractures / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D011859:Radiography; D012189:Retrospective Studies; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000503:physiopathology; D013997:Time Factors
chemical_list: D005938:Glucocorticoids
keywords: Duchenne muscular dystrophy; First fractures; Glucocorticoids; Osteoporosis