Prosthetic knee joint measurement system including energy harvesting and method therefor

Patent metadata

Field	Value
Publication number	US-9259179-B2
Application number	US-201414295242-A
Country	US
Kind code	B2
Filing date	Jun 3, 2014
Priority date	Feb 27, 2012
Publication date	Feb 16, 2016
Grant date	Feb 16, 2016

Abstract

An orthopedic implant having an energy-harvesting device is disclosed. In one embodiment the orthopedic implant is a prosthetic component of a joint of the muscular-skeletal system. The orthopedic implant can include electronic circuitry, a power source, and one or more sensors for measuring a parameter of the muscular-skeletal system or a parameter of in proximity to the implant. The energy-harvesting device generates charge for powering the electronic circuitry using movement of the muscular-skeletal system. The energy-harvesting device comprises a piezo-electric element that converts changes in force into charge that is stored onto a storage device. The energy-harvesting device is coupled to the patella of a knee joint. Movement of the knee joint changes a force applied to the energy-harvesting device thereby generating charge that is coupled to circuitry in a prosthetic component of the knee joint.

First claim

What is claimed is:

1. An orthopedic measurement system comprising:
an energy-harvesting device coupled to a patella;
a storage device coupled to the energy-harvesting device where the energy-harvesting device is configured to produce energy as a knee joint is moved through a range of motion and where the storage device is configured to store energy generated by the energy-harvesting device; and
electronic circuitry coupled to the storage device.

2. The system of claim 1 where the energy-harvesting device comprises a piezo-electric element responsive an applied force.

3. The system of claim 2 where the energy-harvesting device is configured to couple to a region between condyles of a femoral prosthetic component.

4. The system of claim 3 where the energy-harvesting device is configured to convert a change in applied force to electrical energy and where movement of the knee joint is configured to produce a changing force on the piezo-electric element as it moves along the region between condyles of the femoral prosthetic component.

5. The system of claim 1 further including:
one or more sensors coupled to the electronic circuitry configured to measure a parameter; and
a remote system configured to receive quantitative measurement data transmitted by the electronic circuitry.

6. The system of claim 1 further including a button where the button includes a surface that couples to a prepared surface of the patella and where the energy-harvesting device is coupled to an exposed surface of the button.

7. The system of claim 6 where the energy-harvesting device is a piezo-electric element and where the piezo-electric element is encapsulated.

8. The system of claim 7 where the button is cemented to the patella and where the button comprises a polymer material.

9. The system of claim 1 where the energy-harvesting device and the electronic circuitry are coupled by flexible wires and where the electronic circuitry is housed in one or more of a tibial prosthetic component, a femoral prosthetic component, an insert, or the patella.

10. The system of claim 1 where the storage device is a battery or capacitor.

11. An orthopedic measurement system comprising:
a piezo-electric element coupled to a patella;
a storage device coupled to the piezo-electric element where a knee joint is configured to apply a non-constant force to the piezo-electric element as a knee joint moves through a range of motion and where the storage device is configured to store energy generated by the piezo-electric element; and
electronic circuitry coupled to the storage device.

12. The system of claim 11 further including a button where the button includes a surface that couples to a prepared surface of the patella and where the piezo-electric element is coupled to an exposed surface of the button.

13. The system of claim 12 where the piezo-electric element is encapsulated.

14. The system of claim 12 where the button is cemented to the patella and where the button comprises a polymer material.

15. The system of claim 12 where the piezo-electric element couples to a region between condyles of a femoral prosthetic component.

16. The system of claim 11 where the piezo-electric element and the electronic circuitry are coupled by flexible wires and where the electronic circuitry is housed in one or more of a tibial prosthetic component, a femoral prosthetic component, an insert, or the patella.

17. The system of claim 16 further including:
one or more sensors coupled to the electronic circuitry configured to measure a parameter; and
a remote system configured to receive quantitative measurement data transmitted by the electronic circuitry.

18. The system of claim 17 further including a regulator coupled between the storage device and the electronic circuitry.

19. The system of claim 18 where the storage device is a battery or capacitor.

20. A method of providing energy to electronic circuitry comprising the steps of:
moving a knee joint through a range of motion where an energy-harvesting device on a patella couples to a region between condyles of a femoral prosthetic component whereby a variable force is generated on the energy-harvesting device as the knee joint is flexed;
generating energy as the variable force is applied to the energy-harvesting device;
charging a storage device with the energy generated by the energy-harvesting device;
powering electronic circuitry in a prosthetic component with energy harvested from the energy-harvesting device.

Assignees

• Orthosensor Inc

Inventors

• Stein Marc

Classifications

• A61B5/01

  Measuring temperature of body parts {; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue} (clinical contact thermometers G01K13/20) · CPC title

• A61B5/0022

  Monitoring a patient using a global network, e.g. telephone networks, internet · CPC title

• A61B5/6846

  specially adapted to be brought in contact with an internal body part, i.e. invasive · CPC title

• A61B5/4851 Primary

  Prosthesis assessment or monitoring · CPC title

• A61B5/4509

  Bone density determination · CPC title