On-board microprocessor-controlled joints are making prosthetic arms and legs more responsive to environmental barriers and easier to control. CLAIRE RENCKEN explores the fascinating world of bionics.
Specialists in the fields of prosthetics, orthotics and mobility products now offer products to help amputees achieve independence and quality of life through the most advanced technologies.
Take microprocessor-controlled knees, for example. These knees are designed to help you walk with a much more stable and efficient gait, which more closely resembles a natural walking pattern. All microprocessor-controlled knees feature sensors, a microprocessor, software, a resistance system and a battery.
The knee’s internal computer (microprocessor) controls an internal fluid, which may be hydraulic or pneumatic. The internal computer monitors each phase of your walking pattern (gait cycle) using a series of sensors. The continuous monitoring and control of fluid allows the processor to make adjustments in resistance, so that you can walk more efficiently at various speeds and walk more safely down ramps and stairs.
Ottobock knee systems make adjustments in support as you speed up or slow down in real time. Both the Genium and the C-Leg also provide a high level of “stumble recovery” – they sense when you have tripped or stumbled and automatically increase resistance, so that you can catch yourself before you fall.
Another member of the Ottobock family is the Kenevo microprocessor knee – reportedly the first microprocessor knee designed specifically for the activities and challenges of K2 patients (these patients have the ability or potential for ambulation with the ability to traverse low-level environmental barriers such as kerbs, stairs or uneven surfaces). With Kenevo, K2 patients can feel more confident as they go about their daily activities or challenge themselves through the rehab process.
Another option is the Össur Power Knee. It works as an integrated extension of the user, replacing true muscle activity to bend and straighten the knee as required. Also in the Össur stable is the Rheo Knee 3, which again provides natural knee function, because it continuously adapts to the user and the environment.
Amputees in the market for an above-the-elbow prosthesis need look no further than the Dynamic Arm from Ottobock. It incorporates a powerful electric motor in combination with the Vario Drive clutch to help users both flex and extend their elbows – while holding up to as much as almost five kilograms.
When it comes to hands, patients have various options to choose from. Bebionic’s advanced myoelectric hand and Ottobock’s Michelangelo prosthetic hand are both transforming the lives of amputees.
So too is Touch Bionics’s I-Limb Ultra, which looks and moves like a natural hand. Motorised digits allow the hand to bend at the joints of each digit and individual stall out technology gives the hand a compliant grip so that the hand accurately conforms around the shape of the object being grasped. Using its pulsing and vari-grip features, the I-Limb Ultra allows the user to increase the strength of their grip around an object. This can be very useful in situations where a firmer grasp is required, such as when you are tying shoelaces firmly or opening a tightly closed jar of food.
It seems the sky is the limit when it comes to bionics! Watch this space…