J. Shaperman et al., IS BODY POWERED OPERATION OF UPPER-LIMB PROSTHESES FEASIBLE FOR YOUNGLIMB DEFICIENT CHILDREN, Prosthetics and orthotics international, 19(3), 1995, pp. 165-175
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.