This prosthesis is a reality the brainchild of Michael Tompkins of Animated Prosthetics Inc., Greensboro, North Carolina. Collaborating with C. Michael Schuch, C.P.O., Director of the Prosthetics and Orthotics Department, Duke University, Durham, North Carolina, Tompkins began designing the device in 1994. Clinical trials began in early 1996, and since then, about 35 patients, both children and adults, have been fitted with the electronic arm.

     The prosthesis can "grow" with the patient without being re- built. How? As Tompkins and Schuch explain in their paper presented during the 1997 Annual Meeting of the American Academy of Orthotists and Prosthetists, an on-board microcomputer, the ACS (Animation Control System) features many unique methods of monitoring the patient sensors and then controlling the hand and wrist devices. The ACS module, pre-programmed with a power profile which controls the hand accurately and efficiently, is designed to operate most externally powered hands and wrist rotation devices.

Matching Componentry, Skills
Its modes of operation, called TASCs (Techniques, Algorithms, and Strategies of Control), match the components in the prosthesis to the skills of the patient. Two typical TASCs include Voluntary Open Auto Close also known as "cookie cruncher" and Voluntary Open Voluntary Close, using a single myo signal, also known as single site dual function. "The prosthetist simply tells the ACS which devices are connected to it, such as the number and type of myoelectrodes, the type of battery and hand, and it does the rest," Tompkins and Schuch noted in their paper. "The ACS even allows fine-tuning to match the requirements of special applications. Any TASC can work on any hand." The system is compatible with Otto Bock and VASI hands, wrist units, and electrodes, and Centri Ultralite hands, among others.

     The ACS also stores diagnostic information, such as the number of open/close cycles and battery recharges, so the prosthetist can tell exactly how much and how effectively the limb is being used a valuable source of documented outcomes information for third- party payors. The ACS controls the charging of the battery for maxi- mum performance and optimal life.

     The ACS series is currently available in two models: the ACS-1000 and the ACS-1010, which has the features of the ACS-1000, except that it is thin and flat rather than round and may be more suited to patients with longer arms and limited space in the forearm.

     Integral to the system is a device named the PCU (Prosthesis Configuration Unit) which is used to configure and monitor the pros- thesis. The PCU is linked by a radio transceiver to the ACS; through its video screen, the prosthetist can view and modify the prosthesis even as it is being worn. Because of the telemetry link, the PCU does not need to accompany the patient. "Many parameters associated with the arm operation, such as myoelectric signal Ievel, hand speed, proportional or on/off control, maximum grip, number of cycles of operation, etc., can be viewed and modified using this communications link," Tompkins and Schuch reported. Data is presented both graphically and numerically to allow exact tracking of the patient's progress. The prosthesis can be easily adapted to users as they increase in strength and skills, saving money and the prosthetist's time. The PCU also can be used for initial patient myo signal evaluation, eliminating the need for other myo-tester devices.

Configuring and Monitoring the Prosthesis
The PCU is available in two versions: the PCU-705, which is a self- contained system with a five-inch color video monitor; and the PCU- 700, which is a much smaller version using an external video monitor. The video can be attached to any size monitor or VCR. When the keypad is detached, no changes can be made to the arm parameters, and the PCU can go home with the patient to allow biofeedback training. Although the initial cost of the control module is somewhat more than for a pediatric myoelectric unit, the overall system cost is com- parable to others on the market, according to Tompkins. The company sells its products only to "animation specialists" prosthetists who have completed its training course. The learning curve is not extensive, says Tompkins; prosthetists can learn how to use the diagnostic equipment for design and modification in just a few hours.

For more information, contact:
Animated Prosthetics, Inc.
2907 Pacific Avenue
Greensboro, North Carolina 27406
(336) 691-9000
fax: (336) 691-9095
e-maiI: info@animatedprosthetics.com
website: www.animatedprosthetics.com

Page 40
0 & P Business News
December 1, 1999

Reprinted with permission
O&P Business News