Article

Quantitative data on the mechanical performance of upper-limb prostheses are very
important in prostheses development and selection. The primary goal of this study
was to objectively evaluate the mechanical performance of adult-size voluntary
opening (VO) prosthetic terminal devices and select the best tested device. A
second goal was to see whether VO devices have improved in the last two decades.
Nine devices (four hooks and five hands) were quantitatively tested (Hosmer model
5XA hook, Hosmer Sierra 2 Load VO hook, RSL Steeper Carbon Gripper, Otto Bock
model 10A60 hook, Becker Imperial hand, Hosmer Sierra VO hand, Hosmer Soft VO
hand, RSL Steeper VO hand, Otto Bock VO hand). We measured the pinch forces,
activation forces, cable displacements, mass, and opening span and calculated the
work and hysteresis. We compared the results with data from 1987. Hooks required
lower activation forces and delivered higher pinch forces than hands. The
activation forces of several devices were very high. The pinch forces of all
tested hands were too low. The Hosmer model 5XA hook with three bands was the
best tested hook. The Hosmer Sierra VO hand was the best tested hand. We found no
improvements in VO devices compared with the data from 1987.

Langue : ANGLAIS