title: The influence of passive wrist joints on the functionality of prosthetic hands.
abstract: BACKGROUND
  The addition of a passive wrist to a single degree of freedom prosthesis has an effect on its functionality. The amount of impact is undetermined.
  
  
  OBJECTIVE
  To measure the grasping function of a commercial single degree of freedom hands with and without two forms of passive wrist flexor.
  
  
  METHODS
  Form-board and timed tasks.
  
  
  METHODS
  Repeated measures with a single subject using a validated assessment tool. The test measured the function of one conventional, single axis, powered hand controlled by the same myocontroller format. It was used in conjunction with a passive three position wrist flexor, a wrist with compliance in the flex/extend and radial/ulnar deviation and compared with a hand without these axes.
  
  
  RESULTS
  The overall functional score of the hand alone was 80 out of 100. The use of a wrist flexion unit resulted in a higher score (83) and the compliant wrist achieved a score of 79. The addition of a wrist allowed improved performance in Power, Lateral and Tips grips for both wrist designs, in addition the Extension grip was improved with the compliant wrist.
  
  
  CONCLUSIONS
  Wrist flexion had a positive impact on the functional score. It enabled some tasks to be performed quicker and with less difficulty.
authors: University of New Brunswick, Canada. pkyberd@unb.ca
authors: Peter J
authors: PJ
authors: Kyberd
mesh_terms: D004867:Equipment Design; D006225:Hand; D018737:Hand Strength; D006801:Humans; D008422:Materials Testing / Q000295:instrumentation / Q000379:methods; D019736:Prostheses and Implants; D016059:Range of Motion, Articular; D013647:Task Performance and Analysis; D013673:Technology Assessment, Biomedical; D014955:Wrist Joint