Ankle Robotics Training After Stroke
Condition: Seated Treadmill Training; Treadmill Locomotor-based Training; Treadmill Only
MeSH terms: Stroke
Study type: Interventional

Summary: 
      Veterans and other Americans who survive stroke often face disabling motor impairments that
      impede performance of activities of daily living and limit free-living activity. Prominent
      among these are diminished walking and balance functions, which not only foster a sedentary
      lifestyle and physical deconditioning, but also increase the risk of injuries due to falls.
      Recent research has demonstrated how motor learning based interventions can modify brain
      activity and improve motor functions in persons with stroke. Now there is a major research
      opportunity to advance the effectiveness of these interventions by applying new robotics
      technologies to improve control of essential functions such as gait and balance. One critical
      area for performance of walking and standing balance is the control of the ankles, as they
      are a major conduit of mechanical power in gait and also modulate torques affecting the
      motion of the whole body center of mass when balancing. Thus the current proposal is designed
      to investigate two approaches for using an impedance controlled ankle robot to improve gait
      and balance among stroke survivors with chronic lower extremity weakness. One approach uses
      the ankle robot in a seated visuomotor training program that focuses has subjects play video
      games with the weaker ankle to improve paretic ankle motor control that may carry over to
      gait and balance functions. The other approach uses task-specific gait training by
      integrating use of the ankle robot during treadmill exercise training to assess effects on
      the same functions. The effectiveness of both robotics approaches will be compared to that of
      a treadmill exercise program without robotics.
    

Detailed description: 
      Veterans and other Americans who survive stroke often face disabling motor impairments that
      impede performance of activities of daily living and limit free-living activity. Prominent
      among these are diminished locomotor function and impaired balance that not only foster a
      sedentary lifestyle and physical deconditioning, but also increase the risk injuries due to
      falls. Recent research has demonstrated how motor learning based interventions can modify
      brain activity and improve motor functions in persons with stroke. Now there is a major
      research opportunity to advance the effectiveness of these interventions by applying new
      robotics technologies to improve neuromotor control of essential functions such as gait and
      balance. One critical area for performance of walking and standing balance is the control of
      the ankles, as they are a major conduit of mechanical power in gait and also modulate torques
      affecting the motion of the whole body center of mass when balancing. Thus the current
      proposal is designed to investigate two approaches for using an impedance controlled ankle
      robot to improve gait and balance function among stroke survivors with chronic lower
      extremity hemiparesis. One approach uses the ankle robot in a seated visuomotor training
      program that focuses on improving paretic ankle motor control that may transfer to gait and
      balance functions. The other approach follows the dominant rehabilitation paradigm of
      task-specific training by integrating use of the ankle robot during treadmill exercise
      training to assess effects on the same outcomes. The effectiveness of both robotics
      approaches will be compared to that of a treadmill exercise program without robotics.

      The study tests the hypothesis that, in persons with chronic lower extremity hemiparesis, 6
      weeks of seated ankle robot training will improve paretic ankle motor control with major
      improvements in standing balance and moderate improvements in gait, whereas the same amount
      of training on the treadmill with the ankle robot will improve gait function more than
      balance. Both robot-trained groups will outperform the treadmill only group on balance, while
      the treadmill + robot group will make the greatest gains in gait and the seated robot group
      will make some improvement in gait but will show greater gains in ankle motor control and
      balance.

      Aims: In a 6-week intervention (18 sessions) with persons with chronic lower extremity
      hemiparesis 1) Compare effects of seated visuomotor ankle robot training vs. treadmill +
      robot training on paretic ankle impairments and motor control; 2) Compare effects of
      seated-robot vs. treadmill + robot training on functional mobility and balance outcomes; and
      3) Compare the effectiveness of both robotics approaches to a standard treadmill exercise
      protocol of the same duration. This proposal will establish the initial comparative efficacy
      of two motor learning based approaches using a modular impedance controlled ankle robot and
      contrast motor control and functional gait and balance outcomes among them. As a pilot study
      we also will establish initial deficit profiles for users that respond to each intervention
      across the 6-week period.
    

Intervention name(s): Seated Robot Training (SRT); Treadmill Locomotor-based Training (TMR); Treadmill Only (TMO)
Intervention type(s): Behavioral; Behavioral; Behavioral
Intervention description(s): Participants at least 6 mos. post-stroke will use the ankle robot in a seated visuo-motor training paradigm. They will train on the robot 3x weekly for 6-weeks (18 sessions) by playing videogames with the paretic ankle. They will be evaluated on outcomes at baseline, post-6 weeks training, and again after a 6-week retention period with no training.; Treadmill training with ankle robot group. Participants at least 6 mos. post-stroke will wear the ankle robot during treadmill locomotor training. They will walk on a treadmill with the ankle robot adjusted to promote paretic ankle engagement during 3 x weekly training sessions over 6 weeks (18 sessions). They will be evaluated on outcomes at baseline, post-6 weeks training, and again after a 6-week retention period with no training.; Treadmill only group. This group will consist of participants at least 6 mos. post-stroke who engage in treadmill training 3x weekly for 6 weeks without robotic support. They will be volunteers from another treadmill training study and evaluated on outcomes at baseline and post-6 weeks training. They will not receive retention testing at 12 weeks because they will be continuing with regular treadmill training beyond the 6-week period.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Keywords: Stroke; Robotics; Neurorehabilitation