IS BODY POWERED OPERATION OF UPPER-LIMB PROSTHESES FEASIBLE FOR YOUNGLIMB DEFICIENT CHILDREN

The investigators measured efficiencies of body powered prehensors and cable control components of prostheses available for young children. Results indicated that the cable control systems and hook type prehens ors have moderate to high efficiencies, but children's body powered ha nds have very low efficiencies. Measures of arm and shoulder strength of 3-5 year-old limb deficient children, both on the limb deficient an d sound sides, were less than that reported in the literature for norm al findings were examined in children's strength available compared wi th prosthesis strength requirements. The comparison demonstrates a way to establish measurable efficiency targets for new prehensor designs. The article includes detailed findings on children's strength, and fi ndings on efficiencies of the prehensors and cable control systems of children's upper limb prostheses. Sample calculations may be useful to future designers of body powered prehensors for young children. A mor e efficient body powered hand is especially needed. Preliminary calcul ations indicate that the use of currently available children's volunta ry opening (VO), body powered hands is not feasible, given the low str ength of young limb deficient children and the low efficiencies of the VO hands. The use of voluntary closing (VC) hands may be feasible but remains to be tested.