Once in place they are activated by a radio signal from a coil worn by the patient. This controls the frequency and intensity of the electrical stimuli produced by each implant. Doctors can then download a set of exercise programs into a portable controller for the patient to take home. The muscles can be stimulated in other ways, but these require surgery or leave wires sticking out from the skin, increasing the risk of infection. Attaching electrodes to the skin can work, but makes targeting of specific muscle groups difficult, and can burn the skin.
Trials begin Trials of the BIONs began last month.
The implants stimulated these muscles, and the patient reported no ill effects. Lead researcher Dr Gerald Loeb said the BIONs were designed to emit a pulse that while strong enough to stimulate the muscles, would not damage the surrounding tissues. Dr Loeb said the ultimate aim was to design more sophisticated BIONs that can stimulate useful movement. This could, for example, enable a patient with a spinal cord injury or a debilitating stroke to grasp an object with their hand. However, this would require implants that can sense movement as well as stimulating muscle contraction.