Stroke is one of the leading causes of
motor disability in the United States [1]. Although conventional
therapies involve
different forms of movement practice, technological advances have
allowed the development of interactive therapies using robotics and
other computer based interventions, such as virtual reality and computer
games. These approaches have the advantages of monitoring movement
features on a continuous and incremental basis, as well as providing
feedback to patients about instantaneous performance. To date, such
approaches have
overwhelmingly focused on patients with mild motor deficits [2]. This is
likely related to the fact that motor disabilities reduce a patient’s
ability to interact with such systems, and because patients with more
severe disorders show smaller responses to intervention. In fact, a
recent review by Coupar and colleagues suggested that the level of
initial severity of motor deficits is the most important predictive
factor for recovery of function in the upper limb [3]. Patients with
moderate to severe paresis tend to have limited active range of motion
due to decreased voluntary
control, abnormal synergies, and spasticity. However, movement range can
be systematically increased when the limb is supported against gravity
in patients with moderate to severe paresis [4-6]. We now combine the
approaches of supporting the arm against gravity with a virtual reality
interactive design that is tailored to the patients’ abilities in two
individuals with chronic and severe hemiparesis. The patients’ arms are
supported on a friction free air-sled system to remove the effects of
gravity and friction and optimize range of motion in the horizontal
plane. We present an interactive computer-game system using our custom
virtual reality display system, adjusting the gain of the feedback to
encourage maximal engagement in the game-like reaching task. We then
adjust feedback gains, in accord with improvements in movement
amplitude, in order to encourage continuous adaptation. We evaluate a
4-week training regime by assessing reaching performance during a
3-dimensional unsupported
reaching task, as well as, assessing changes in dysfunction level, using
the Fugl-Meyer Motor Assessment (FMA) protocol [7]. Following a 4-week
training protocol, involving 3 one-hour sessions per week, our results
show significant improvements in movement range and quality during
unsupported reaching and clinically significant improvements in the FMA
of sensorimotor dysfunction.
Does every single thing written about strokes start out by saying "stroke is one of the leading causes of disability...."
ReplyDelete