Systems and methods for implantable leadless bone stimulation

• US 8,494,644 B2
• Filed: 11/09/2011
• Issued: 07/23/2013
• Est. Priority Date: 06/20/2006
• Status: Active Grant

• Current Assignee: EBR Systems, Inc.
• Original Assignee: EBR Systems, Inc.
• Inventors: Cowan, Mark W., Riley, Richard E., Brisken, Axel F., Echt, Debra S.
• Primary Examiner(s): Bertram, Eric D.
• Application Number:
  US13/292,854
• Publication Number:
  US 20120059433A1
• Time in Patent Office: 622 Days
• Field of Search: 607/51
• US Class Current: 607/51
• CPC Class Codes: A61N 1/326 for promoting growth of cells, e.g. bone cells
• CPC Class Codes: A61N 1/36007 of urogenital or gastrointestinal organs, e.g. for incontinence control
• CPC Class Codes: A61N 1/36021 for treatment of pain
• CPC Class Codes: A61N 1/36038 Cochlear stimulation
• CPC Class Codes: A61N 1/3604 for correcting spinal deformities, e.g. scoliosis
• CPC Class Codes: A61N 1/36071 Pain
• CPC Class Codes: A61N 1/37217 characterised by the communication link, e.g. acoustic or tactile
• CPC Class Codes: A61N 1/37288 Communication to several implantable medical devices within one patient
• CPC Class Codes: A61N 1/3756 Casings with electrodes thereon, e.g. leadless stimulators
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

Systems and methods are disclosed to enhance bone growth by stimulating bone sites for bone regrowth, fusion, or grafts. The invention uses electrical stimulation of the bone site, where vibrational energy from a source is received by an implanted device and converted to electrical energy and the converted electrical energy is used by implanted electrodes to stimulate the bone site. The vibrational energy is generated by a controller-transmitter, which could be located either externally or implanted. The vibrational energy is received by a receiver-transmitter, which could be incorporated into an orthopedic device, such as pin, cage, plate or prosthetic joint used for bone healing.

Claims

1. A system for bone stimulation therapy comprising:

an implantable acoustic controller-transmitter, wherein the controller-transmitter comprises acoustic transducers disposed in a housing and one or more sensors disposed on an external surface of the housing, and wherein the one or more sensors are configured to detect an electrical stimulation output; and

an implantable acoustic receiver-stimulator having an electrode assembly adapted to be in electrical communication with bone, wherein the controller-transmitter is adapted to transmit acoustic energy and the receiver-stimulator is adapted to receive acoustic energy and the controller-transmitter provides energy and signal information to the receiver-stimulator to provide electrical stimulation energy to bone;

wherein the controller-transmitter is configured to sense the electrical stimulation energy using one or more of the sensors, and wherein the controller-transmitter is configured to adjust the transmitted acoustic energy to compensate for changes in the electrical stimulation energy.

2. A system of claim 1, wherein the receiver-stimulator comprises an acoustic receiver which receives acoustic energy and generates alternating current means for converting the alternating current to a pre-determined waveform, and electrodes adapted to deliver the pre-determined waveform to stimulate the bone.

3. A system of claim 2, wherein the implantable receiver-stimulator is adapted to be located in close proximity to a bone stimulation site.

4. A system of claim 3 wherein the predetermined bone stimulation site is selected for bone regrowth, bone repair, fusion of bones, or fusion of bone grafts.

5. A system of claim 4, wherein the implantable receiver-stimulator is adapted to be placed and secured to the bone stimulation site effective in healing bone.

6. A system of claim 5 wherein the transmitted acoustic energy is applied to the general area of the bone stimulation site as well as the implanted receiver-stimulator to provide simultaneous ultrasonic therapy and electrical stimulation therapy through the receiver-stimulator.

7. A system of claim 4, further comprising two or more receiver-stimulator devices.

8. A system of claim 7, wherein the system is programmed to activate the receiver stimulator devices sequentially.

9. A system of claim 7, wherein the system is programmed to activate the receiver stimulator devices simultaneously.

10. A system of claim 1, wherein the controller-transmitter comprises a power source, control and timing circuitry to provide a stimulation signal, means for converting the stimulation signal to an acoustic energy signal, and means for transmitting the acoustic energy signal to the receiver-stimulator.

11. A system of claim 10, wherein the control circuitry included one or more means for sensing physiologic variables to vary the stimulation signal.

12. A system of claim 1, adapted to transmit and receive acoustic energy wherein the frequency of the acoustic energy is between 20 kHz and 10 MHz, the burst length is between 3 cycles and a continuous burst, the duty cycle is between 0.01% and 100.00%, and the mechanical index is less than 1.9.

13. A system for bone healing therapy comprising:

an externally applied acoustic controller-transmitter, wherein the controller-transmitter comprises acoustic transducers disposed in a housing and one or more sensors disposed on an external surface of the housing, and wherein one or more of the sensors are configured to detect an electrical stimulation output; and

an implantable acoustic receiver-stimulator housed within a bone attachment device having, an electrode assembly adapted to be in electrical communication with bone, wherein the controller-transmitter is adapted to transmit acoustic energy, the receiver-stimulator is adapted to receive the acoustic energy and convert the received acoustic energy into electrical stimulation energy, and the controller-transmitter provides both energy and signal information to the receiver-stimulator sufficient to provide electrical stimulation to bone;

wherein the controller-transmitter is configured to sense the electrical stimulation energy using one or more of the sensors, and wherein the controller-transmitter is configured to adjust the transmitted acoustic energy to compensate for changes in the electrical stimulation energy.

14. A system of claim 13, wherein the receiver-stimulator comprises an acoustic receiver which receives acoustic energy and generates alternating current, means for converting the alternating current to a to a pre-determined waveform, and electrodes adapted to deliver the pre-determined waveform to stimulate the bone.

15. A system of claims 14, wherein the bone attachment device is adapted to be placed and secured to stimulate bone sites effective in healing bone.

16. A system of claim 15, wherein the transmitted acoustic energy is externally directed to the general area of the bone fracture as well as the implanted receiver-stimulator to provide simultaneous ultrasonic therapy and electrical stimulation therapy through the receiver-stimulator.

17. A system of claim 13, wherein the bone attachment device is adapted to be located at a location in close proximity to a bone stimulation site.

18. A system of claim 13, wherein the predetermined bone stimulation site is selected for bone regrowth, bone repair, fusion of bones, or fusion of bone grafts.

19. A system of claim 18, further comprising two or more receiver-stimulator device.

20. A system of claim 19, wherein the system is programmed to activate the receiver stimulator devices sequentially.

21. A system of claim 19, wherein the system is programmed to activate the receiver-stimulator devices simultaneously.

22. A system of claim 13, wherein the externally applied controller-transmitter comprises a power source, control and timing circuitry to provide a stimulation signal, means for converting the stimulation signal to an acoustic energy signal, and means for transmitting the acoustic energy signal to the receiver-stimulator.

23. A system of claim 22, wherein control circuitry includes one or more means for sensing physiologic variables to vary the stimulation signal.

24. A system for stimulating bone as in claim 13, adapted to transmit and receive acoustic energy wherein the frequency of the acoustic energy is between 20 kHz and 10 MHz, the burst length is between 3 cycles and a continuous burst, the duty cycle is between 0.01% and 100,00%, and the mechanical index is less than 1.9.