Patent ID: 7195645

Claim:
A joint endoprosthesis system for use in a joint comprising two bones interfacing at a joint articulation in a patient's body, the joint endoprosthesis system comprising: a first prosthetic component; a second prosthetic component; a bearing component having a bearing surface to be placed against the first prosthetic component and a second surface to be placed against the second prosthetic component, the interface of the first prosthetic component and the bearing surface of the bearing component defining a joint articulation; a signal source received within one of the prosthetic components on one side of the joint articulation and being capable of generating a first signal selected from the group consisting of a magnetic field and a magnetic flux density; a sensor received within the other prosthetic component across the joint articulation from the signal source, the sensor being capable of producing a voltage, the magnitude of the voltage being dependent upon the magnitude of the first signal; a modulator received within one of the prosthetic components and connected to receive the voltage generated by the sensor and being capable of converting the voltage received into a transmitter signal having a characteristic that varies depending on the magnitude of the voltage generated by the sensor; and an internal transmitter received within one of the prosthetic components and connected to receive the transmitter signal from the modulator, the internal transmitter being capable of transmitting the transmitter signal from within the patient's body to a location outside of the patient's body.