User demands for sensory feedback in upper extremity prostheses

This paper presents the results of 108 responses to a survey asking users of electrical upper limb prostheses about sensory feedback. The survey aimed to identify whether sensory feedback was of interest to users, which kinds of information were important and what feedback modality would be suited for transfer of information. Moreover the situations in which sensory feedback would be most useful should be identified. To answer these questions we designed a survey which was sent by mail and was also available online. 88% of respondents placed different degree of importance on obtaining sensory feedback from their prosthesis. Grip force was most important followed by proprioceptive information. First contact during grasping and end of contact during release of an object was also of interest to respondents. Vibration, pressure and electrical stimulation were identified as appropriate means for transmission of sensory information from the prosthesis to the amputee, based on their acceptance and sensitivity at the residual limb. These findings allow conclusions for further development on what information has to be measured by feedback prostheses and how this information can be transmitted to the amputee. Investigation of perceptions respondents apply to control their current electrical prosthesis reveals that observation, listening and sensations at the residual limb are used and applied to gain certain information about the prosthesis. This could be the basis for a training of prosthesis users aiming at prosthesis control with less visual attention.