VASSTII: An Exploratory Clinical Study on a VASST IITreadmill System for Post Stroke Gait Rehabilitation.
Condition: Stroke; Hemiplegic Gait
MeSH terms: Stroke; Gait Disorders, Neurologic
Study type: Interventional

Summary: 
      An exploratory clinical study on a Variable Speed and Sensing Treadmill system(VASST) for
      hemiparetic gait rehabilitation after stroke.

      Building upon the positive results of VASST I conducted in 2012, VASST II will be an open
      label pilot trial of 11 subjects screened for eligibility by TTSH medical and rehabilitation
      team Study hypotheses : Training on VASST may result in a gain of +40% - 50% for distance
      walked and +10-20% of gait speed compared to baseline and response rate of 85% and serious
      adverse event rate of <10%.
    

Detailed description: 
      A recent collaboration with Ngee Ann Polytechnic's team from the Biomedical Engineering
      Centre, Electronic & Computer Engineering Division, School Of Engineering Singapore yielded
      the VASST I; an innovative product, the result of co development between NP and TTSH
      rehabilitation centre's CART (Centre for Advanced Rehabilitation Therapeutics) was supported
      by a competitive grant. (EMBC paper ref, SIRF)

      VASST I incorporates the following features which enhance manual treadmill training:

        1. Sensing mechanisms to track user's self-activated actions during exercise.

        2. Automated speed-control to adapt to a user's gait speed and pattern.

        3. Safety sensing to slow down the treadmill when the user is unable to sustain the
           treadmill speed in order to avert a potential fall.

        4. Overhead safety harness without body weight support for reduction of fall risk.

        5. Software tools to collect vital clinical data regarding ambulatory gait speed, distance
           and time walked during treatment.

      A recently completed proof of concept trial in June 2013 yielded encouraging results in 10
      chronic poststroke hemiplegic subjects. All subjects completed the trial without any adverse
      events. The clinical team was able to smoothly test-bed VASST in 10 subjects with good
      subjective feedback. Following 12 hour - long supervised training sessions over 4 weeks,
      there were significant gains from baseline for measures of gait quantity (+30.1%) and gait
      speed (+8.7%). These gains were maintained for up to 4 weeks after training ceased. The
      response rate was 80% and positive feedback was obtained in 80% of subjects. Objective
      measurements were obtained using independent kinematic gait analysis using the Gaitrite
      system.

      With these encouraging results, the combined TTSH and Ngee Ann medical and bioengineering
      teams have brought the co-development to a deeper level, leading to VASST II which is
      conceptualized as a pre-commercialisation prototype.

      Additional technological improvements include:

        1. Automated unweighting subsystem of up to 20% body weight support to benefit more
           severely impaired subjects in terms of reduction of physical fatigue during ambulation
           and to reduce destabilization or fall risk during higher gait training speeds.

        2. Hand grip sensors to intelligently guide progression of training speeds

        3. Instrumentation subsystem including sensors to record spatial and temporal gait
           measurements during gait training such as step and stride length, gait speed / distance
           walked. An anticipated sensor accuracy of +/- 1.27 cm similar to the Gaitrite system in
           measuring step length may potentially allow ambulatory gait monitoring, obviating the
           need for additional independent post-training analysis using a gait measurement
           instrument such as Gaitrite.

        4. Real-time feedback subsystem with graphical LCD display which is interactive and varied
           in order reduce boredom and motivate users.

        5. Wireless data transfer subsystem for data storage and analysis to a laptop computer for
           the treating therapist.

      Research objectives

        1. To provide clinical inputs into VASST II via systematic hazard analyses, in order to
           arrive at a prototype which may attract commercial interest for licensing and
           manufacture and eventual deployment to ambulatory rehabilitation clinics in hospitals
           and day rehabilitation centres.

        2. To conduct of a pilot clinical trial using VASST II for 11 subacute to chronic (>3
           months) hemiplegic stroke patients in an ambulatory setting.

        3. To obtain pre and post outcomes using standardized clinical scales and objective
           measurements of gait parameters during exercise. (gait speed, quantity, cadence, step
           length)

        4. To obtain subjective feedback with regards to their experience after using VASST II from
           research subjects and therapists.
    

Intervention name(s): VASST II treadmill
Intervention type(s): Device
Intervention description(s): Supervised treadmill training under physiotherapist
Other intervention name(s): Variable Automated Speed and Sensing Treadmill version II
Intervention model: Single Group Assignment
Intervention model description: 1 hour of VASST II training, total 15 sessions over 5 weeks continuously
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Stroke; Treadmill; Gait Speed