Effect of multi-grip myoelectric prosthetic hands on daily activities, pain-related disability and prosthesis use compared with single-grip myoelectric prostheses : A single-case study

OBJECTIVE: To evaluate the effect of multi-grip myoelectric prosthetic hands on performance of daily activities, pain-related disability and prosthesis use, in comparison with single-grip myoelectric prosthetic hands. DESIGN: Single-case AB design. PATIENTS: Nine adults with upper-limb loss participated in the study. All had previous experience of single-grip myoelectric prostheses and were prescribed a prosthesis with multi-grip functions. METHODS: To assess the changes in daily activities, pain-related disability and prosthesis use between single-grip and multi-grip myoelectric prosthetic hands, the Canadian Occupational Performance Measure, Pain Disability Index, and prosthesis wearing time were measured at multiple time-points. Visual assessment of graphs and multi-level linear regression were used to assess changes in the outcome measures. RESULTS: At 6 months' follow-up self-perceived performance and satisfaction scores had increased, prosthesis wearing time had increased, and pain-related disability had reduced in participants with musculoskeletal pain at baseline. On average, 8 of the 11 available grip types were used. Most useful were the power grip, tripod pinch and lateral pinch. CONCLUSION: The multi-grip myoelectric prosthetic hand has favourable effects on performance of, and satisfaction with, individually chosen activities, prostheses use and pain-related disability. A durable single-grip myoelectric prosthetic hand may still be needed for heavier physical activities. With structured training, a standard 2-site electrode control system can be used to operate a multi-grip myoelectric prosthetic hand.