Apparatus, system, and method for transcutaneously transferring energy

• US 20070004994A1
• Filed: 06/30/2005
• Published: 01/04/2007
• Est. Priority Date: 06/30/2005
• Status: Active Grant

• Current Assignee: Depuy Products Incorporated (Johnson & Johnson)
• Original Assignee: Depuy Products Incorporated (Johnson & Johnson)
• Inventors: Sherman, Jason
• Granted Patent: US 7,780,613 B2
• Time in Patent Office: Days
• US Class Current: 602/26
• CPC Class Codes: A61B 5/0008 Temperature signals
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/145 Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissuemeasuring of blood pressure or blood flow A61B5/02; non-radiation detecting or locating of foreign bodies in blood A61B5/06
• CPC Class Codes: A61F 2/30 Joints
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2002/30668 Means for transferring electromagnetic energy to implants
• CPC Class Codes: A61F 2250/0001 Means for transferring electromagnetic energy to implants

Abstract

An apparatus for transcutaneously transferring an amount of energy to an implantable orthopaedic device includes a primary coil. The primary coil has a resonant frequency matched to a resonant frequency of a secondary coil, which may form part of the implantable orthopaedic device. The primary coil may have an aperture configured to receive a portion of a patient'"'"'s body or may include a substantially “C”-shaped core. A power circuit may be coupled with the primary coil to provide power to the coil. The apparatus may also include a wireless receiver, a measuring device, and/or a display.

Claims

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

2. The apparatus of claim 1, wherein the primary coil is a toroidal primary coil.

3. The apparatus of claim 1, wherein the aperture has an inner diameter greater than about 6 inches.

4. The apparatus of claim 3, wherein the inner diameter is about 8.5 inches.

5. The apparatus of claim 1, 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.

6. The apparatus of claim 1, wherein the primary coil includes a number of turns formed from Litz wire.

7. The apparatus of claim 6, wherein the Litz wire has a strand count of about 50 strands or greater.

8. The apparatus of claim 7, wherein the Litz wire has a strand count of about 100 strands or greater.

9. The apparatus of claim 1, wherein the resonant frequency of the primary coil is adjustable to match the resonant frequency of a different secondary coil of an implantable orthopaedic device.

10. The apparatus of claim 1, wherein the resonant frequency of the primary coil is less than about 9 kilohertz.

11. The apparatus of claim 10, wherein the resonant frequency of the primary coil is about 5 kilohertz.

12. The apparatus of claim 1, wherein resonant frequency of the primary coil is matched to the resonant frequency of the secondary coil using a capacitive device.

13. The apparatus of claim 1, wherein the primary coil is wound around a bobbin, the bobbin having a handle to facilitate positioning of the primary coil by a caregiver.

14. The apparatus of claim 1, wherein the implantable orthopaedic device includes an electrical circuit configured to receive power from the secondary coil.

15. The apparatus of claim 14, wherein the electrical circuit includes a transmitter configured to transmit sensory data in response to a power signal received from the secondary coil.

16. The apparatus of claim 1, wherein the primary coil is coupled with a knee brace, the knee brace being configured to be coupled to a leg of the patient.

17. The apparatus of claim 1, further comprising a power circuit configured to supply a power signal to the primary coil to cause the primary coil to generate an alternating magnetic field.

18. The apparatus of claim 17, wherein the power circuit includes a wireless receiver configured to receive data signals from the implantable orthopaedic device.

19. The apparatus of claim 17, wherein 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.

20. The apparatus of claim 17, wherein the power circuit includes a direct current power source configured to produce a direct current power signal and a converter configured to convert the direct current power signal to an alternating current power signal.

21. The apparatus of claim 20, wherein the power circuit and the primary coil are positioned in a portable housing.

22. 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.

23. The method of claim 22, 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.

24. The method of claim 22, wherein the supplying step includes supplying a power signal having a frequency matched to a resonant frequency of the primary coil.

25. The method of claim 24, wherein the supplying step includes supplying a power signal having a frequency of about 9 kilohertz or less.

26. The method of claim 22, further comprising tuning a resonant frequency of the primary coil to match a resonant frequency of the secondary coil.

27. The method of claim 22, further comprising receiving a wireless data signal from the orthopaedic device.

28. A limb brace comprising:

a brace structure configured to be coupled to a limb of a patient; and

a primary coil coupled to the brace structure and having a resonant frequency matched to a resonant frequency of a secondary coil of an implantable orthopaedic device.

29. The limb brace of claim 28, wherein the primary coil circumferentially surrounds a portion of the limb of the patient while the brace is coupled to the limb.

30. The limb brace of claim 28, wherein the primary coil is a toroidal primary coil.

31. The limb brace of claim 28, wherein the primary coil is wound around a portion of a “

C”

-shaped ferrite core.

32. The limb brace of claim 28, wherein the primary coil is inductively couplable with the secondary coil while the brace structure is coupled to the limb of the patient.

33. The limb brace of claim 28, wherein the primary coil is spaced away from a skin surface of the limb while the brace structure is coupled to the limb of the patient.

34. The limb brace of claim 28, wherein the resonant frequency of the primary coil is adjustable to match the resonant frequency of a different secondary coil of an implantable orthopaedic device.

35. The limb brace of claim 28, wherein the resonant frequency of the primary coil is less than about 9 kilohertz.

36. The limb brace of claim 35, wherein the resonant frequency of the primary coil is about 5 kilohertz.

37. The limb brace of claim 28, wherein the brace structure is configured to couple to a leg of the patient.