Apparatus, system, and method for transcutaneously transferring energy
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.
1 . An apparatus for transcutaneously transferring an amount of energy to an implantable orthopaedic device, the apparatus comprising:
a core having a substantially “C”-shaped side profile; and
a primary coil wound around a portion of the core, the primary coil having 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 core is a ferrite core.
3 . The apparatus of claim 1 , wherein the core includes an elongated middle portion, a first end portion extending from one distal end of the elongated middle portion, and a second end portion extending from an opposite distal end of the elongated portion, the first and second end portions being coplanar with each other, the primary coil being wound around the elongated middle portion.
4 . The apparatus of claim 3 , wherein the first and second end portions extend substantially orthogonally from the elongated middle portion.
5 . The apparatus of claim 3 , wherein a length of the elongated portion is sized based on a length of the secondary coil of the implantable orthopaedic device.
6 . The apparatus of claim 3 , wherein the elongated middle portion, the first end portion, and the second end portion form a unitary core.
7 . The apparatus of claim 1 , wherein the core has a substantially circular cross-section profile.
8 . 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.
9 . The apparatus of claim 1 , wherein the resonant frequency of the primary coil is less than about 9 kilohertz.
10 . The apparatus of claim 9 , wherein the resonant frequency of the primary coil is about 5 kilohertz.
11 . The apparatus of claim 1 , wherein resonant frequency of the primary coil is matched to the resonant frequency of a secondary coil using a capacitive device.
12 . The apparatus of claim 1 , further comprising a bobbin having an aperture, the core being positioned in the aperture and the primary coil being wound around the bobbin and the core.
13 . The apparatus of claim 1 , wherein the implantable orthopaedic device includes an electrical circuit configured to receive power from the secondary coil.
14 . The apparatus of claim 13 , wherein the electrical circuit includes a transmitter configured to transmit sensory data in response to a power signal received from the secondary coil.
15 . 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.
16 . 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.
17 . The apparatus of claim 16 , wherein the power circuit includes a wireless receiver configured to receive data signals from the implantable orthopaedic device.
18 . The apparatus of claim 16 , 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.
19 . The apparatus of claim 16 , 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.
20 . The apparatus of claim 19 , wherein the power circuit and the primary coil are positioned in a portable housing.
21 . 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:
positioning a primary coil having a substantially “C”-shaped ferrite core near the portion of the patient's body 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.
22 . The method of claim 21 , 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.
23 . The method of claim 21 , wherein the supplying step includes supplying a power signal having a frequency matched to a resonant frequency of the primary coil.
24 . The method of claim 23 , wherein the supplying step includes supplying a power signal having a frequency of about 9 kilohertz or less.
25 . The method of claim 21 , further comprising tuning a resonant frequency of the primary coil to match a resonant frequency of the secondary coil.
26 . The method of claim 21 , further comprising receiving a wireless data signal from the orthopaedic device.
27 . A method for determining a location of an orthopaedic device implanted in a patient's body, the method comprising:
moving a primary coil over a portion of the patient's body having the orthopaedic device implanted therein;
measuring an amount of power used by the primary coil; and
determining the location of the orthopaedic device based on the measuring step.
28 . The method of claim 27 , wherein the moving step includes receiving the portion of the patient's body with an aperture defined by the primary coil such that the primary coil circumferentially surrounds the portion.
29 . The method of claim 27 , wherein the moving step includes positioning a primary coil having a substantially “C”-shaped ferrite core near the portion of the patient.
30 . The method of claim 27 , wherein the moving step includes positioning the primary coil such that the primary coil is coplanar with at least a portion of the orthopaedic device.
31 . The method of claim 27 , wherein the moving step includes positioning the primary coil such that the primary coil is inductively coupled with a secondary coil of the orthopaedic device.
32 . The method of claim 27 , wherein the moving step includes moving the primary coil until the amount of power used by the primary coil is at or above a predetermined threshold value.
33 . The method of claim 27 , wherein the determining step includes determining the location of the orthopaedic device when the amount of power used by the primary coil is at or above a predetermined threshold value.
34 . The method of claim 27 , further comprising tuning a resonant frequency of the primary coil to match a resonant frequency of a secondary coil of the orthopaedic device.
35 . The method of claim 27 , further comprising receiving a wireless data signal from the orthopaedic device.