title: Stable muscle atrophy in long-term paraplegics with complete upper motor neuron lesion from 3- to 20-year SCI.
abstract: METHODS
  Unrandomized trial.
  
  
  OBJECTIVE
  To investigate the structural and functional relationships and the progression of muscle atrophy up to 20 years of spastic paraplegia.
  
  
  METHODS
  Clinical follow-up in Vienna, Austria; muscle biopsies analyzed by light microscopy in Padova and by electron microscopy (EM) in Chieti, Italy.
  
  
  METHODS
  Force was measured as knee extension torque; trophism by computer tomography scan; tissue composition and fiber morphology by histopathology and EM.
  
  
  RESULTS
  In the long-term group of patients (17.0+/-2.6 years), force and size of thigh muscles were only slightly different from those of mid-term subjects (2.2+/-0.5 years). Histology and ultrastructure confirm that the difference in average size of muscle fibers between long-term and mid-term paralyzed leg muscles is actually very small. In addition, muscle fibers maintain the striated appearance characteristic of normal skeletal fibers even after 14-20 years of paralysis. Ultrastructural alterations of the activating and metabolic machineries, and the presence of fibers with lower motor neuron denervation features, may explain the low-force output and the reduced endurance of paretic muscles.
  
  
  CONCLUSIONS
  The stable muscle atrophy that characterizes long-lasting spastic paraplegia suggests that there are no upper-time limits to begin a training program based on functional electrical stimulation.
authors.affiliation: Department of Physical Medicine, Ludwig Boltzmann Institute of Electrostimulation and Physical Rehabilitation, Wilhelminenspital, Vienna, Austria.
authors.forename: H
authors.initials: H
authors.lastname: Kern
authors.forename: C
authors.initials: C
authors.lastname: Hofer
authors.forename: M
authors.initials: M
authors.lastname: Mödlin
authors.forename: W
authors.initials: W
authors.lastname: Mayr
authors.forename: V
authors.initials: V
authors.lastname: Vindigni
authors.forename: S
authors.initials: S
authors.lastname: Zampieri
authors.forename: S
authors.initials: S
authors.lastname: Boncompagni
authors.forename: F
authors.initials: F
authors.lastname: Protasi
authors.forename: U
authors.initials: U
authors.lastname: Carraro
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000502:physiology; D009133:Muscular Atrophy / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D010264:Paraplegia / Q000150:complications* / Q000473:pathology* / Q000503:physiopathology; D052097:Quadriceps Muscle / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D011859:Radiography; D013119:Spinal Cord Injuries / Q000150:complications* / Q000473:pathology* / Q000503:physiopathology; D013904:Thoracic Vertebrae; D013997:Time Factors