The fact that the hand is such a debilitating body part to lose has spurred researchers to develop a functional and aesthetically pleasing bionic replacement. While seemingly not as severe as the loss of an entire hand, the loss of fingers can be just as much of a hindrance and represents the largest group of arm amputees. Short of removing the remaining partial hand, there has been no bionic option available to replace missing fingers. Now, a developer of upper-limb bionic technologies has addressed this deficit with the launch of ProDigits, the world’s first powered-bionic finger.
Made by Touch Bionics, the same company responsible for the i-LIMB Hand, each ProDigits prosthetic build is unique; just as each partial-hand patient is unique. Sockets are custom-designed and fabricated by clinicians to suit the individual’s specific needs. The key to enabling the fitting of many different partial hand configurations lies in each finger (including thumbs) being capable functioning as a standalone unit.
There are two control strategies that can be employed to power ProDigits: either myoelectric sensors that register muscle signals from the residual finger or palm, or a pressure sensitive switch input in the form of a force sensitive resistor (FSR), or touch pad, which relies on the remnant digit or tissue surrounding the metacarpal bone to provide the necessary pressure to activate the finger. As with the i-LIMB Hand, a unique stall feature allows the device to detect when it has closed around an object, also allowing users to point single digits and configure the hand in various grip patterns.