Smart joint implant sensors

• US 20080065225A1
• Filed: 08/03/2007
• Published: 03/13/2008
• Est. Priority Date: 02/18/2005
• Status: Active Grant

• Current Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Inventors: Komistek, Richard, Mahfouz, Mohamed, Wasielewski, Ray
• Granted Patent: US 8,956,418 B2
• Time in Patent Office: Days
• US Class Current: 623/18.11
• CPC Class Codes: A61B 2562/028 Microscale sensors, e.g. electromechanical sensors [MEMS]
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/03 Detecting, measuring or recording fluid pressure within the body other than blood pressure, e.g. cerebral pressure; Measuring pressure in body tissues or organs A61B5/205 takes precedence
• CPC Class Codes: A61B 5/076 Permanent implantations telemetry using implanted circuitry A61B5/0031; implanted stimulators for therapy A61N1/3605, A61N1/362, A61N1/372
• 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: A61B 5/14507 specially adapted for measuring characteristics of body fluids other than blood devices for taking samples of body liquids A61B10/0045
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14539 for measuring pH
• CPC Class Codes: A61B 5/4528 Joints A61B5/4533, A61B5/4538 take precedence
• CPC Class Codes: A61B 5/4851 Prosthesis assessment or monitoring
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61F 2/38 for elbows or knees
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2/4657 Measuring instruments used for implanting artificial joints for surgical instruments A61B90/06
• CPC Class Codes: A61F 2/4684 Trial or dummy prostheses
• CPC Class Codes: A61F 2/488 Means for detecting or monitoring wear
• CPC Class Codes: A61F 2002/30133 kidney-shaped or bean-shaped
• CPC Class Codes: A61F 2002/3067 for data transfer
• CPC Class Codes: A61F 2002/30673 : Lubricating means, e.g. synovial pocket
• CPC Class Codes: A61F 2002/30878 : with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
• CPC Class Codes: A61F 2002/4632 : using computer-controlled surgery, e.g. robotic surgery
• CPC Class Codes: A61F 2002/4666 : for measuring force, pressure or mechanical tension
• CPC Class Codes: A61F 2230/0015 : Kidney-shaped, e.g. bean-shaped
• CPC Class Codes: A61F 2250/0002 : for data transfer
• CPC Class Codes: A61L 27/50 : Materials characterised by their function or physical properties , e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
• CPC Class Codes: G16H 40/20 : for the management or administration of healthcare resources or facilities, e.g. managing hospital staff or surgery rooms
• CPC Class Codes: G16H 40/63 : for local operation
• CPC Class Codes: G16H 40/67 : for remote operation

Abstract

A prosthesis for implantation into a mammalian body, the device comprising: (a) a prosthesis for implantation into a mammalian body that includes a sensor array comprising a plurality of sensors mounted to the prosthesis; and (b) an electronics structure for receiving signals from the sensor array and wirelessly transmitting representative signals to a remote receiver, where the plurality of sensors are operative to sense pressure, applied to the prosthesis by another object, in at least two axes generally perpendicular to one another.

Claims

1. A prosthesis for implantation into a mammalian body, the device comprising:

a prosthesis for implantation into a mammalian body that includes a sensor array comprising a plurality of sensors mounted to the prosthesis; and

an electronics structure for receiving signals from the sensor array and wirelessly transmitting representative signals to a remote receiver;

wherein the plurality of sensors are operative to sense pressure, applied to the prosthesis by another object, in at least two axes generally perpendicular to one another.

2. The prosthesis of claim 1, wherein the electronics structure includes a timing circuit configured to automatically activate the sensor array and to automatically deactivate the sensor array.

3. The prosthesis of claim 1, wherein the plurality of sensors include at least one of resistive microcantilevers, piezoelectric microcantilevers, and microcapacitor sensors.

4. The prosthesis of claim 1, wherein the prosthesis includes at least one of a knee replacement femoral prosthesis, a knee replacement tibial prosthesis, a knee replacement tibial tray prosthesis, a hip replacement femoral prosthesis, a hip replacement acetabular cup prosthesis, a hip replacement acetabular cup insert prosthesis, a trial knee replacement femoral prosthesis, a trial knee replacement tibial prosthesis, a trial knee replacement tibial tray prosthesis, a trial hip replacement femoral prosthesis, a trial hip replacement acetabular cup prosthesis, and a trail hip replacement acetabular cup insert prosthesis.

5. The prosthesis of claim 1, wherein at least one of the sensor array and the electronics structure is powered using at least one of electromagnetic induction, radio frequency induction, and battery power.

6. The prosthesis of claim 1, wherein the electronics structure includes a microcontroller and a transmitter.

7. The prosthesis of claim 1, wherein the electronics structure includes an application specific integrated circuit, which includes a filter for filtering out low frequency noise.

8. The prosthesis of claim 1, wherein the electronics structure includes an application specific integrated circuit, which includes an amplifier for amplifying signals from the sensor array.

9. The prosthesis of claim 1, wherein the electronics structure includes an application specific integrated circuit, which includes a multiplexer for multiplexing signals from the sensor array.

10. The prosthesis of claim 1, wherein the electronics structure includes an application specific integrated circuit, which includes an analog-to-digital converter for converting analog signals from the sensor array to digital signals.

11. The prosthesis of claim 1, wherein the electronics structure includes an application specific integrated circuit, which includes a processor for processing signals from the sensor array.

12. The prosthesis of claim 1, wherein at least one of the plurality of sensors is operative to sense temperature.

13. The prosthesis of claim 1, wherein the prosthesis includes a microchannel and a micropump in communication with the microchannel to pump mammalian bodily fluid bathing the joint through the microchannel, where an interior of the microchannel is in communication with at least one of the plurality of sensors.

14. A prosthesis for implantation into a mammalian body, the device comprising:

a prosthesis for implantation into a mammalian body that includes a sensor array comprising a plurality of sensors mounted to the prosthesis; and

an electronics structure for receiving signals from the sensor array and wirelessly transmitting representative signals to a remote receiver;

wherein at least one of the plurality of sensors is in fluid communication with fluids bathing the prosthesis.

15. The prosthesis of claim 14, wherein the sensor array includes sensors detecting at least one of a predetermined component, a predetermined contaminant, and a predetermined property.

16. The prosthesis of claim 14, wherein the electronics structure includes a timing circuit configured to automatically activate the sensor array and to automatically deactivate the sensor array.

17. The prosthesis of claim 14, wherein the plurality of sensors include at least one of resistive microcantilevers, piezoelectric microcantilevers, and microcapacitor sensors.

18. The prosthesis of claim 14, wherein the prosthesis includes at least one of a knee replacement femoral prosthesis, a knee replacement tibial prosthesis, a knee replacement tibial tray prosthesis, a hip replacement femoral prosthesis, a hip replacement acetabular cup prosthesis, a hip replacement acetabular cup insert prosthesis, a trial knee replacement femoral prosthesis, a trial knee replacement tibial prosthesis, a trial knee replacement tibial tray prosthesis, a trial hip replacement femoral prosthesis, a trial hip replacement acetabular cup prosthesis, and a trail hip replacement acetabular cup insert prosthesis.

19. The prosthesis of claim 14, wherein at least one of the plurality of sensors of the sensor array is operative to sense at least one of:

leukocyte concentration, neutrophil concentration, bacterial deoxyribonucleic acid concentration, antibody concentration, glucose concentration, excitatory amino acids concentration, lactate dehydrogenase concentration, hyaluronic acid concentration, uric acid concentration, calcium pyrophosphate concentration, beta-glucuronidase concentration, nerve growth factor concentration, insulin-like growth factor concentration, Caeruloplasmin concentration, and oxidase concentration.

20. The prosthesis of claim 14, wherein at least one of the sensor array and the electronics structure is powered using at least one of electromagnetic induction, radio frequency induction, and battery power.

21. The prosthesis of claim 14, wherein the electronics structure includes a microcontroller and a transmitter.

22. The prosthesis of claim 14, wherein the electronics structure includes an application specific integrated circuit, which includes a filter for filtering out low frequency noise.

23. The prosthesis of claim 14, wherein the electronics structure includes an application specific integrated circuit, which includes an amplifier for amplifying signals from the sensor array.

24. The prosthesis of claim 14, wherein the electronics structure includes an application specific integrated circuit, which includes a multiplexer for multiplexing signals from the sensor array.

25. The prosthesis of claim 14, wherein the electronics structure includes an application specific integrated circuit, which includes an analog-to-digital converter for converting analog signals from the sensor array to digital signals.

26. The prosthesis of claim 14, wherein the electronics structure includes an application specific integrated circuit, which includes a processor for processing signals from the sensor array.

27. The prosthesis of claim 14, wherein the prosthesis includes a microchannel and a micropump in communication with the microchannel to pump mammalian bodily fluid bathing the joint through the microchannel, where an interior of the microchannel is in communication with at least one of the plurality of sensors.

27-1. (canceled)

28. A method of monitoring a prosthetic implant and its host mammalian body, the method comprising the steps of:

implanting a sensor array into the mammalian body, the sensor array mounted to a prosthesis also implanted into the mammalian body;

sensing pressure applied to the prosthesis in at least two axes generally perpendicular to one another;

generating signals responsive to the sensed pressure applied to the prosthesis by another object; and

wirelessly transmitting signals to a remote receiver outside of the mammalian body, the transmitted signals being representative of signals generated by the sensor array in response to sensing the pressure.

29-43. -43. (canceled)

44. A method of monitoring a prosthetic implant and its host mammalian body, the method comprising the steps of:

implanting a sensor array into the mammalian body, the sensor array mounted to a prosthesis also implanted into the mammalian body, where at least one sensor of the sensor array is in fluid communication with fluids bathing the prosthesis;

sensing a condition of at least one of a predetermined component, a predetermined contaminant, and a predetermined property using the sensor array;

generating signals responsive to the sensed condition; and

wirelessly transmitting signals to a remote receiver outside of the mammalian body, the transmitted signals being representative of signals generated by the sensor array in response to sensing the condition.

45-59. -59. (canceled)

60. A method of fabricating a prosthesis, the method comprising:

fabricating a prosthesis with a fluid conduit adapted to be in fluid communication with a mammalian bodily fluid bathing the prosthetic joint; and

orienting a plurality of sensors into fluid communication with the interior of the fluid conduit, where the sensors are operative to detect at least one of a predetermined component, a predetermined contaminant, and a predetermined property.

61. A sensor array comprising:

a first capacitive sensor comprising conductive plates separated by a dielectric material, the capacitive plates of the first capacitive sensor lying along a first X-Y and operative to detect pressure along the X axis;

a second capacitive sensor comprising conductive plates separated from one another, the capacitive plates of the second capacitive sensor lying along the first X-Y plane and operative to detect pressure along the Y axis; and

a third capacitive sensor comprising conductive plates separated from one another, the capacitive plates of the third capacitive sensor lying along the first X-Y plane and operative to detect pressure along a Z plane orthogonal to the first X-Y plane.

62. A prosthetic implant comprising:

a prosthetic sensor array mounted to a prosthesis, the sensor array including at least one sensor in fluid communication with a fluid surrounding the prosthesis subsequent to implanting the prosthesis into a mammalian body, where the at least one sensor is operative to detect at least one of the following properties;

viscosity of the synovial fluid;

pH of the synovial fluid;

cell count within the synovial fluid;

protein within the synovial fluid;

phospholipids within the synovial fluid;

hyaluronic acid within the synovial fluid;

leukocytes within the synovial fluid;

neutrophils within the synovial fluid;

bacterial deoxyribonucleic acid within the synovial fluid;

antibodies within the synovial fluid;

glucose concentration within the synovial fluid;

lactate dehydrogenase (LDH) within the synovial fluid;

uric acid crystals within the synovial fluid;

MMP-9 antigens (gelatinase-B) within the synovial fluid;

nerve growth factor within the synovial fluid;

excitatory amino acids (EAA) glutamate and aspartate within the synovial fluid;

insulin-like growth factor I (IGF-I) and its binding proteins (IGFBP) 3 and 4 within the synovial fluid;

oxidase activity within the synovial fluid;

polyamine oxidases within the synovial fluid;

caeruloplasmin (Cp) concentration within the synovial fluid;

beta-glucuronidase content within the synovial fluid;

S100A8/A9 within the synovial fluid;

C reactive protein within the synovial fluid;

rheumatoid factor within the synovial fluid;

C3 and C4 within the synovial fluid;

metal particulate within the synovial fluid;

polyethylene particulate within the synovial fluid;

bone particulate within the synovial fluid;

cement particulate within the synovial fluid;

osteolytic enzymes within the synovial fluid;

genetic markers within the synovial fluid;

antibody markers within the synovial fluid;

temperature of the synovial fluid;

specific gravity of the synovial fluid; and

white cells (and differential cell type) within the synovial fluid; and

a transmitter in electrical communication with the at least one sensor of the sensor array and operative to transmit data to a remote receive indicative of at least one sensed property.