What is a simple option for pre-positioning the prosthetic elbow in flexion for a TH amputee using a body-powered prosthesis?

Moving the proximal base plate and retainer on the humeral section anterior is a simple option for pre-positioning the prosthetic elbow in flexion for a transhumeral (TH) amputee using a body-powered prosthesis. By adjusting the base plate and retainer anteriorly, the tension created by the harness system allows for greater flexion at the elbow joint when the user pulls on the cable or engages the system. This adjustment positions the elbow in a way that encourages flexion, making it easier for the user to operate the prosthetic arm effectively.

In body-powered systems, the orientation of the base plate directly influences the mechanical advantage of the cable and the joint’s position, allowing for more flexibility depending on the user’s functional requirements. Proper adjustment is essential for optimizing the range of motion and facilitating easier and more comfortable use of the prosthesis.

The other options either do not effectively promote flexion or pertain to factors that may not directly influence the positioning of the elbow in a way that meets the intended function and ease of use. For example, adjusting the elbow joint to a neutral position typically doesn't provide any pre-positioning in flexion. Similarly, changing the material for the humeral section may impact weight and comfort but does