Upper Limb Prosthetics - Van Lunteren's Wallet

Kim Doolan
LIVINGSKIN®
Middletown, New York

In the hopes of learning more about the benefits and burdens of body-powered and electric prostheses, a group of researchers at Delft University of Technology studied 42 unilateral, upper limb amputees in the late 1970s. One particular finding that struck the current presenter as worthy of modern demonstration was the numerous approaches amputees took to remove money from a wallet and the subsequent conclusion that "direct use of the grasping function [of the terminal device] is an exception."

Unilateral, transhumeral and transradial amputees who wore a variety of terminal devices (TDs) were observed in their homes and found to engage their prostheses in various ways, whether or not their TDs provided active grasp. These ways, demonstrated through photographs, show that to remove money, amputees might:

  1. Hold a wallet in their TD and use their sound hand to remove money;

  2. Place a wallet on a counter top, stabilize it underneath their TD and use their sound hand to remove money;

  3. Sandwich a wallet between the forearm or upper arm of their prosthesis and their body, and use their sound hand to remove money;

  4. Balance a wallet on the surface of their TD or forearm, and use their sound hand to remove money;

  5. Place a wallet on a counter top, use only their sound hand to remove money and not involve the prosthesis at all;

  6. Ask someone else to remove money from their wallet;

  7. Avoid the use of a wallet altogether, carry money in their pocket, and use their sound hand to remove it.

None of the amputees in the older or newer studies used their TDs to pull bills or coins from their wallets, although some were taught how in clinic settings. All the amputees who completed the task in a natural manner reported teaching themselves and not having practitioners show them. Many reported that using their TDs in ways that didn't cause them to assume odd postures, actually made them feel more spontaneous and comfortable using their prostheses.

The presenter would like clinicians to better understand that while there may be multiple ways of completing a single task, the ways that appear most natural are typically the most repeated. And, more often than not, those ways do not involve the grasping function of the TD.

Bibliography: Van Lunteren, A, Van Lunteren-Gerritsen, GHM, Stassen, HG, Zuithoff, MJ, A field evaluation of arm prostheses for unilateral amputees. Prosthetics and Orthotics International, 1983, 7, pp 141-151.