The Effect of Resistance to Participant-Supported Reaching on Workspace of the Hand in Severe Chronic Stroke
Condition: Stroke
MeSH terms: Stroke
Study type: Interventional

Summary: 
      Disturbances in movement coordination are the least well understood but often the most
      debilitating with respect to functional recovery following stroke. These deficits in
      coordination are expressed in the form of abnormal muscle synergies and result in limited and
      stereotypic movement patterns that are functionally disabling. The result of these
      constraints in muscle synergies is an abnormal coupling between shoulder abduction and elbow
      flexion (i.e. the flexion synergy), which significantly reduces the reaching function of an
      individual with stroke when they lift up the weight of the impaired arm against gravity. The
      investigators previous neurotherapeutic research, supported by a NIDRR Field Initiated
      research grant, has shown that the abnormal synergy between shoulder abduction and elbow
      flexion can be significantly reduced thus increasing total reaching range of motion in
      individuals with severe stroke. The previous work established progressive abduction loading
      as a key element to the rehabilitation of reaching. Although individuals with severe stroke
      benefited from the investigators previous work, residual flexion synergy continued to hinder
      normal arm function in most participants with severe stroke. This study will utilize the
      ACT3D robot, developed as part of the investigators previous NIDRR project, to incorporate
      resistance to reaching while accounting for the known benefits of progressive abduction
      loading. The investigators propose to randomize forty participants with severe stroke into
      two closely related interventions. The groups will both practice reaching under abduction
      loading, however, the experimental group will also move against resistance while reaching.
      Rigorous and quantitative investigation of therapeutic elements such as resistance to
      reaching and progressive abduction loading is only possible with a device such as the ACT3D.
      the investigators will be able to standardize the delivery of each intervention using
      kinematic and kinetic parameters, which will allow for a clear identification of the
      therapeutic effect of resistance to reaching. the investigators hypothesize that resistance
      to reaching in combination with progressive abduction loading will further increase dynamic
      multi-joint strength, increase total reaching range of motion, and increase arm function thus
      enhancing actual amount of use of the arm, participation in life roles, and quality of life
      in individuals with severe stroke.
    


Intervention name(s): Impairment-based robotic intervention for reaching function
Intervention type(s): Behavioral
Intervention description(s): All participants will undergo 8 weeks of reaching practice in the ACT3D. Frequency and duration will be matched at three 1.5-hour sessions per week. All reaching practice will include abduction (gravity) loading standardized to the participant's motor abilities. The experimental group intervention will also include a horizontal viscous resistant element similar to pushing the arm through molasses.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Basic Science
Keywords: arm; strength; coordination; physical therapy; robotics; stroke; synergy