Researchers have tested medical devices in animals which connect directly to the nervous system, transmitting data to external wireless health monitors without invasive procedures. Other advancements include bionic devices which, by plugging into the body's nerves, can receive orders from the brain and muscular system: "Once the device is inserted into the nerve, nerve fibres grow through it. Nerve signals associated with particular movements are then selected, and these signals transmitted wirelessly to a receiver in the prosthetic."
via bigthink.com
Another step...