Stroke participants' perceptions of robotic and electrical stimulation therapy: a new approach.

PURPOSE: User perceptions are critical, yet often ignored factors in the design and development of rehabilitation technologies. In this article, measures for collection of patient perceptions are developed and applied to a novel upper limb workstation that combines robotic therapy and electrical stimulation (ES). METHOD: Five participants with chronic upper limb hemiplegia post-stroke used a robotic workstation to undertake supported tracking tasks augmented by precisely controlled ES to their triceps muscle. Following a 6 week trial, a purpose designed set of questions was developed and individual interviews were conducted by an independent health psychologist. RESULTS: The simple, quick to administer question set showed that participants had a positive response to the system, and contributed valuable feedback with regard to its usability and effectiveness. Participants want a home-based system targeting their whole arm. CONCLUSION: This article demonstrates the value in assessing user perceptions of a rehabilitation system via a simple question set. While the results of this study have implications for a wider audience, our recommendations are for a qualitative study to develop a generic evaluation tool which could be used across the growing number of devices to provide feedback to enhance future development of any new technology for rehabilitation.

A model of the upper extremity using FES for stroke rehabilitation.

A model of the upper extremity is developed in which the forearm is constrained to lie in a horizontal plane and electrical stimulation is applied to the triceps muscle. Identification procedures are described to estimate the unknown parameters using tests that can be performed in a short period of time. Examples of identified parameters obtained experimentally are presented for both stroke patients and unimpaired subjects. A discussion concerning the identification's repeatability, together with results confirming the accuracy of the overall representation, is given. The model has been used during clinical trials in which electrical stimulation is applied to the triceps muscle of a number of stroke patients for the purpose of improving both their performance at reaching tasks and their level of voluntary control over their impaired arm. Its purpose in this context is threefold: Firstly, changes occurring in the levels of stiffness and spasticity in each subject's arm can be monitored by comparing frictional components of models identified at different times during treatment. Secondly, the model is used to calculate the moments applied during tracking tasks that are due to a patient's voluntary effort, and it therefore constitutes a useful tool with which to analyze their performance. Thirdly, the model is used to derive the advanced controllers that govern the level of stimulation applied to subjects over the course of the treatment. Details are provided to show how the model is applied in each case, and sample results are shown.