Apparatus, system, and method for transcutaneously transferring energy

1. A method for transcutaneously transferring an amount of energy to a secondary coil of an orthopaedic device implanted in a portion of a patient's body, the method comprising:

receiving the portion of the patient's body with an aperture defined by a primary coil such that the primary coil circumferentially surrounds the portion;

positioning the primary coil such that the primary coil is substantially coplanar with the orthopaedic device; and

supplying a power signal to the primary coil to cause the primary coil to generate an alternating magnetic field.

2. The method of claim 1 , wherein the positioning step includes positioning the primary coil such that the primary coil is spaced away from a skin surface of the portion of the patient's body.

3. The method of claim 1 , wherein the supplying step includes supplying a power signal having a frequency matched to a resonant frequency of the primary coil.

4. The method of claim 3 , wherein the supplying step includes supplying a power signal having a frequency of about 9 kilohertz or less.

5. The method of claim 1 , further comprising tuning a resonant frequency of the primary coil to match a resonant frequency of the secondary coil.

6. The method of claim 1 , further comprising receiving a wireless data signal from the orthopaedic device.

7. A system, comprising

an implantable orthopaedic device comprising a secondary coil having a resonant frequency, and

an apparatus to transcutaneously transfer an amount of electrical energy to the implantable orthopaedic device, the apparatus comprising a primary coil to transfer the amount of electrical energy to the secondary coil of the implantable orthopaedic device, the primary coil having (i) an aperture configured to receive a portion of a patient's body and (ii) a resonant frequency matched to the resonant frequency of the secondary coil of the implantable orthopaedic device.

8. The system of claim 7 , wherein the primary coil is a toroidal primary coil.

9. The system of claim 7 , wherein the aperture has an inner diameter greater than about 6 inches.

10. The system of claim 7 , wherein the primary coil is spaced away from a skin surface of the portion of the patient's body while the portion is received by the aperture.

11. The system of claim 7 , wherein the resonant frequency of the primary coil is adjustable to match the resonant frequency of a different secondary coil of another implantable orthopaedic device.

12. The system of claim 7 , wherein the resonant frequency of the primary coil is less than about 9 kilohertz.

13. The system of claim 7 , wherein resonant frequency of the primary coil is matched to the resonant frequency of the secondary coil using a capacitive device.

14. The system of claim 7 , wherein the primary coil is wound around a bobbin, the bobbin having a handle to facilitate positioning of the primary coil by a caregiver.

15. The system of claim 7 , wherein the implantable orthopaedic device includes an electrical circuit configured to receive power from the secondary coil.

16. The system of claim 15 , wherein the electrical circuit includes a transmitter configured to transmit sensory data in response to a power signal received from the secondary coil.

17. The system of claim 7 , wherein

the apparatus further comprises a power circuit configured to supply a power signal to the primary coil to cause the primary coil to generate an alternating magnetic field, and

the power circuit includes a measuring device and a display, the measuring device configured to measure an amount of power used by the primary coil and display the amount of power to a user of the apparatus via the display.