title: Late-onset Becker muscular dystrophy: Refining the clinical features and electrophysiological findings.
abstract: BACKGROUND
  The aim of this study was to characterize a unique distribution of muscle involvement in sporadic Becker muscle dystrophy (BMD).
  
  
  METHODS
  Retrospective chart review, clinical examination, electrophysiological studies, cardiac testing, and genetic testing were performed in 5 patients.
  
  
  RESULTS
  Predominant weakness and atrophy of biceps brachii, hip adduction, and quadriceps muscles was noted along with calf and extensor forearm hypertrophy. Finger flexor muscles were severely weak in 3 of 5 patients, a feature that could lead to a misdiagnosis of inclusion body myositis. Creatinine kinase was only mildly elevated in most patients. Electromyography was abnormal in all patients. Muscle biopsy in 1 patient demonstrated normal immunostaining for dystrophin.
  
  
  CONCLUSIONS
  We found a unique and uniform distribution of muscle involvement in 5 sporadic cases of BMD. Recognizing these features is important for differentiating it from other myopathies that may have similar features and avoids unnecessary invasive procedures such as muscle biopsy.
authors.affiliation: Neuromuscular Disorders Section, Department of Neurology, The University of North Carolina at Chapel Hill, North Carolina, USA.
authors.forename: Tania
authors.initials: T
authors.lastname: Beltran Papsdorf
authors.affiliation: Neuromuscular Disorders Section, Department of Neurology, The University of North Carolina at Chapel Hill, North Carolina, USA.
authors.forename: James F
authors.initials: JF
authors.lastname: Howard
authors.affiliation: Neuromuscular Disorders Section, Department of Neurology, The University of North Carolina at Chapel Hill, North Carolina, USA.
authors.forename: Nizar
authors.initials: N
authors.lastname: Chahin
mesh_terms: D000328:Adult; D004576:Electromyography / Q000379:methods*; D055724:Electrophysiological Phenomena; D006801:Humans; D008297:Male; D008875:Middle Aged; D020388:Muscular Dystrophy, Duchenne / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology*; D012189:Retrospective Studies; D055815:Young Adult
keywords: Becker muscular dystrophy; EMG; finger flexor weakness; muscle biopsy; muscle disease [185]; quadriceps weakness