Abstract
Purpose
Individuals who require manual wheelchairs after stroke are typically taught to ambulate with compensatory propulsion (i.e., using their non-paretic arm and foot), risking disuse of the paretic arm. We investigated whether stroke survivors can instead ambulate in a bimanual, lever-driven wheelchair that requires the paretic arm to contribute half the propulsive input.
Materials and methods
Seventeen individuals with chronic stroke and severe hemiparesis (upper extremity Fugl–Meyer scores between 10 and 24) participated across two experiments. In the first experiment, participants (n = 12) ambulated in straight paths. In the second experiment, participants (n = 12) also performed turns, using an improved version of the wheelchair that incorporated handbrakes. Twelve unimpaired controls also completed the second experiment. Motion capture and EMG were used to compare biomechanics between groups.
Results
Altogether, 15 of 17 participants with stroke could ambulate 30 m in straight paths, and 9 of 12 could turn 1800° entirely under the power of their paretic arm. Participants with stroke exhibited largely healthy biomechanics, with minimal shoulder hiking/leaning or trunk inclination. Their arm muscle EMG patterns were similar to those used by unimpaired participants, excepting delayed elbow extensor activation.
Conclusions
Individuals with severe arm impairment in the chronic stage of stroke retain sufficient strength and coordination with their paretic arm to manoeuvre bimanual, lever-driven wheelchairs. We suggest bimanual, lever-driven propulsion should be explored in stroke rehabilitation practice as an alternative to compensatory wheelchair propulsion, as it has the potential to exercise healthy movement synergies, which may in turn help drive use-dependent motor recovery.
Severe arm impairment arising after stroke does not generally eliminate the motor dexterity needed to bimanually propel a manual wheelchair, provided that the wheelchair is modified to remove the requirement to grasp and release the push rim.
Such exercise appears a good candidate to facilitate rehabilitation outcomes because it depends on alternating muscle activity and improving elbow extension.
Such wheelchair propulsion involves largely normal biomechanics; shoulder hiking and leaning are absent and trunk inclination is rare.
Implications for rehabilitation
Acknowledgements
The authors thank Justin Rowe for his assistance writing the motion capture software and Vicky Chan for recruiting and coordinating all experimental participants.
Disclosure statement
Zondervan DK and Reinkensmeyer DJ are co-founders of and hold equity in Flint Rehabilitation Devices, a company that is commercializing rehabilitation technology. Zondervan DK is currently employed at Flint, and Reinkensmeyer DJ has received payment for consulting from Flint. Reinkensmeyer DJ holds equity in Hocoma, a manufacturer of rehabilitation technology. The terms of Reinkensmeyer DJ’s interests have been reviewed by the U.C. Irvine Conflict of Interest committee.