OrthoHand Flex: Design, Modeling and Evaluation of a 3D-Printed
Wrist-Hand Grasping Orthosis for Stroke Survivors
Abstract
To better comprehend the upper-limb needs and challenges stroke
survivors face, and the issues associated with existing technology, the
authors conversed with 153 members of the ecosystem (60 neuro patients,
30 caregivers, and 63 medical providers). Patients fell into two
populations depending on their upper-limb impairment: spastic (stiff,
clenched hands) and flaccid (limp hands). The authors chose to focus on
the second category and developed a set of design constraints based on
the information collected through customer discovery. With these in
mind, they designed and prototyped OrthoHand Flex, a 3D-printed powered
wrist-hand grasping orthosis (exoskeleton) to aid in recovery. The
orthosis is easily custom-sized based on two parameters and derived
anatomical relationships. The researchers tested the prototype on a
survivor of stroke and modeled the kinematic behavior of the orthosis
with and without load. The prototype neared or exceeded the target
design constraints and was able to grasp objects consistently and
stably, as well as exercise the patientsâ\euro™ hands. In particular,
donning time was only 42 seconds, as compared to the next fastest time
of 7 minutes reported in literature. This device has the potential to
revolutionize neurorehabilitation by making assistive devices accessible
to patients at home, and it lays the foundation for clinical trials and
further device development