title: Swing phase resistance enhances flexor muscle activity during treadmill locomotion in incomplete spinal cord injury.
abstract: BACKGROUND
  This study investigated whether loading the legs during the swing phase of walking enhances flexor muscle activity in ambulatory patients with incomplete spinal cord injury (SCI).
  
  
  METHODS
  Nine patients had surface electromyography (EMG) and joint kinematics recorded from the lower extremities during treadmill walking. Swing phase loading of the legs was achieved by weights (1-3 kg) attached to each lower extremity or by a velocity-dependent resistance applied by the Lokomat robotic gait orthosis.
  
  
  RESULTS
  When patients walked with the weights, there was a consistent increase in the activity of the knee flexors and sometimes of hip or ankle flexor activity during swing. Similarly, when the robot applied the velocity-dependent resistance during walking, swing phase flexor EMG activity tended to be greater. Enhanced knee flexion was observed in all patients after the weights or the robot-generated resistance was removed.
  
  
  CONCLUSIONS
  Flexor muscle activity during swing can be enhanced through additional proprioceptive input in patients with incomplete SCI with brief aftereffects. Further testing of this strategy is necessary to determine if it can improve the gait of ambulatory patients.
authors.affiliation: University of British Columbia, Vancouver, Canada. tania.lam@ubc.ca
authors.forename: Tania
authors.initials: T
authors.lastname: Lam
authors.forename: Markus
authors.initials: M
authors.lastname: Wirz
authors.forename: Lars
authors.initials: L
authors.lastname: Lünenburger
authors.forename: Volker
authors.initials: V
authors.lastname: Dietz
mesh_terms: D000368:Aged; D004576:Electromyography; D005080:Exercise Test; D056228:Feedback, Sensory / Q000502:physiology*; D005260:Female; D006801:Humans; D007866:Leg; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000503:physiopathology*; D009989:Orthotic Devices; D016059:Range of Motion, Articular; D012371:Robotics; D013119:Spinal Cord Injuries / Q000503:physiopathology* / Q000534:rehabilitation*; D016138:Walking / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology