title: Focal amyotrophy in multiple sclerosis.
abstract: BACKGROUND
  The assumption that multiple sclerosis (MS) is purely a white matter disease has been challenged in recent years by observations of axonal damage and neuronal loss in gray matter of the cortex, subcortex, and spinal cord.
  
  
  METHODS
  We report the case of a 71-year-old man with primary progressive MS and longstanding right arm weakness who presented with intermittent right arm pain.
  
  
  RESULTS
  Neurological examination showed atrophy, weakness, and hyporeflexia, and electromyography (EMG) showed acute and chronic partial denervation in multiple segments of the right arm. Magnetic resonance imaging (MRI) demonstrated asymmetric volume loss and increased T2 signal in the right anterior spinal cord from C3 to C7, with no evidence of nerve root compression.
  
  
  CONCLUSIONS
  Lower motor neuron involvement of his right arm was caused by MS with involvement of either the anterior horn cells or the intraspinal motor nerve roots.
authors.affiliation: Department of Neurology, San Francisco VA Medical Center, University of California, 505 Parnassus Avenue, Box 0114, M-798, San Francisco, California, 94143, USA.
authors.forename: Rabia
authors.initials: R
authors.lastname: Malik
authors.forename: Viktoriya
authors.initials: V
authors.lastname: Irodenko
authors.forename: Lara
authors.initials: L
authors.lastname: Zimmermann
authors.forename: Ari
authors.initials: A
authors.lastname: Green
authors.forename: Robert
authors.initials: R
authors.lastname: Layzer
mesh_terms: D000368:Aged; D066193:Cervical Cord / Q000473:pathology; D004576:Electromyography; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009103:Multiple Sclerosis / Q000150:complications*; D009133:Muscular Atrophy / Q000209:etiology*; D009460:Neurologic Examination
keywords: amyotrophy; axonal; demyelination; multiple sclerosis; spinal cord