title: Postural sway and motor control in trans-tibial amputees as assessed by electroencephalography during eight balance training tasks.
abstract: BACKGROUND
  The purpose of this study was to investigate the changes in the Power Spectral Density (PSD) of the electroencephalogram (EEG) during 8 common sensorimotor balance training tasks of varying difficulty in single-limb trans-tibial amputees.
  
  
  METHODS
  Eight sensorimotor balance exercises, including alteration in vision, base of support, and surface compliance, were used to test postural control and how it related to the electroencephalogram (EEG). A control group was compared to a group of people with trans-tibial amputation of 1 leg to see how the brain responds to loss of a single limb during progressively harder balance testing. Postural sway and EEG changes of the alpha, beta, and sigma wave bands were measured in 20 participants (10 controls, 10 amputees) during 8 balance tasks of varying difficulty with eyes open and closed, feet in tandem or apart, and on a foam or a firm surface.
  
  
  RESULTS
  The power of alpha, beta, and sigma bands increased significantly in most tests when comparing the amputees to the control subjects. Balance was significantly worse in the amputees even when standing on both legs. In amputees, balance required more cortical activity than in the controls.
  
  
  CONCLUSIONS
  This study demonstrated that amputees have considerably more difficulty in motor control for the brain during balance tasks. Balance was impaired even when standing feet apart on 2 legs and EEG showed more spectral power in all areas of the brain in the amputees.
authors.affiliation: Department of Physical Therapy, Program in Orthotics and Prosthetics, Loma Linda University, Loma Linda, CA, USA.
authors.forename: Jerrold Scott
authors.initials: JS
authors.lastname: Petrofsky
authors.affiliation: Department of Physical Therapy, Program in Orthotics and Prosthetics, Loma Linda University, Loma Linda, CA, USA.
authors.forename: Iman Akef
authors.initials: IA
authors.lastname: Khowailed
mesh_terms: D000328:Adult; D000674:Amputees; D016022:Case-Control Studies; D004566:Electrodes; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D009044:Motor Cortex / Q000503:physiopathology; D004856:Postural Balance / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D019736:Prostheses and Implants; D013647:Task Performance and Analysis; D013977:Tibia / Q000601:surgery*