Novel Design of a Transradial Socket to Allow Independent Pro-Supination Control in a Myoelectric Prosthesis

Background/Objectives: Individuals with transradial limb loss or absence often retain the ability to pro-supinate their forearm, but the traditional design of the prosthesis precludes this motion from being used for direct prosthesis control. Methods: A prosthetic arm was created for a single user that employed a novel split inner socket to allow pro-supination of the residuum to control a powered prosthetic wrist rotator. A total of 14 subjects (13 able-bodied subjects and one prosthesis user) performed the Refined Clothespin Relocation Test. The user performed the test with their own and a novel research prosthesis, which allowed independent hand and wrist function. Movements of limb segments were recorded using a motion capture system and an analysis of limb segment angles and compensatory motion was made. Results: The research prosthesis reduced compensation in the trunk and head and reduced pain in some joints, while the time to complete the test increased. Conclusions: This method has the potential to create additional intuitive control channels for transradial prostheses.