Method and apparatus for implant identification

• US 7,474,223 B2
• Filed: 04/18/2005
• Issued: 01/06/2009
• Est. Priority Date: 04/18/2005
• Status: Active Grant

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Inventors: Nycz, Jeffrey H., Varner, Robert, Tethrake, Steven M., Elliott, Paul, Pelo, Mark
• Primary Examiner(s): Bugg; George A
• Assistant Examiner(s): Mehmood; Jennifer
• Application Number:
  US11/108,130
• Publication Number:
  US 20060232408A1
• Time in Patent Office: 1,359 Days
• Field of Search: 3405681-5729, 600/424, 600/431, 600/325, 600/327, 600/332, 600/339, 600/423, 606 86 R-1055, 623/16.11, 623/23.63, 128/843
• US Class Current: 340/572.8
• CPC Class Codes: A61B 17/8605 Heads, i.e. proximal ends projecting from bone
• CPC Class Codes: A61B 90/90 Identification means for patients or instruments, e.g. tags
• CPC Class Codes: A61B 90/98 using electromagnetic means, e.g. transponders
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/34 Acetabular cups
• CPC Class Codes: A61F 2/3662 Femoral shafts
• CPC Class Codes: A61F 2/367 Proximal or metaphyseal parts of shafts trochanteric devices connected to said proximal parts A61F2/30739
• CPC Class Codes: A61F 2/38 for elbows or knees
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2/3877 Patellae or trochleae
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2/488 Means for detecting or monitoring wear
• CPC Class Codes: A61F 2002/3067 for data transfer
• CPC Class Codes: A61F 2002/3071 Identification means; Administration of patients
• CPC Class Codes: A61F 2002/3611 Heads or epiphyseal parts of femur
• CPC Class Codes: A61F 2002/4632 using computer-controlled surgery, e.g. robotic surgery
• CPC Class Codes: A61F 2250/0002 for data transfer
• CPC Class Codes: A61F 2250/0085 Identification means; Administration of patients
• CPC Class Codes: G16H 10/65 stored on portable record carriers, e.g. on smartcards, RFID tags or CD

Abstract

A method and apparatus for automatically identifying surgical implants by use of a radio-frequency tag (RFID) is disclosed. The method, apparatus, and system enable a radio-frequency tagged implant to receive an interrogation signal from a reader and to respond to the interrogation signal with identifying information about the tagged implants. The interrogation signal interrogates the implant to ascertain its information, and the RFID tag affixed on the implant in turn transmits a signal back to the reader. The method, apparatus, and system can track, inspect, and verify surgical implants, to assess, for example, any wear and tear on implants, and/or positional displacement of components of the implant.

Claims

1. A method for obtaining information concerning a surgical implant, comprising:

presenting a subject into a radio frequency field of a reader device, the subject having one or more surgical implants and corresponding fasteners, at least one of the fasteners having affixed thereto one or more radio frequency identification tags storing positional data including the axial position of the fastener relative to the one or more surgical implants;

transmitting an interrogation signal from the reader device;

receiving the interrogation signal by the one or more radio frequency tagged surgical instruments;

transmitting back to the reader device, an RF signal containing the positional data from the radio frequency tags of the one or more surgical implants; and

comparing the data received from the at least one radio frequency tag of the one or more surgical implants to a database.

2. The method of claim 1, wherein the one or more radio frequency identification tags are activated by an RF field transmitted by the reader device.

4. The method of claim 1, wherein the RF signal transmitted back from the one or more frequency identification tags is directly transmitted via a wireless protocol to the transceiver of the reader device.

5. The method of claim 1, wherein the at least one RFID tag is affixed on the implant at areas susceptible to wear, tear, and break.

6. The method of claim 5, wherein the at least one RFID tag is passive and employs a frequency having a propagation characteristics conducive to the transmission of radio signals within the human body.

7. The method of claim 5, wherein the at least one RFID tag is encased in glass.

8. The method of claim 1, wherein the reader device is connected to one or more components selected from the group consisting of a desk computer, a hand-held computer, a personal digital assistant, and combinations thereof.

9. The method of claim 8, wherein the one or more components are wireless fidelity local area network enabled.

10. The method of claim 8, wherein the reader device is a member of a mesh network that includes multiple sensors employing micro-electro-mechanical systems (MEMS).

11. The method of claim 1, wherein the at least one RFID tag includes information selected from one or more of the group consisting of axial dimensions, part number, name, manufacturer, age, positional data regarding the position of the implant and its component parts, and the number of times the implant has been diagnosed.

12. The method of claim 1, wherein transmitting the radio frequency signals comprises transmitting the radio frequency signals based upon propagating electromagnetic waves.

3. The method of clam 1, wherein the RF reader comprises at least an antenna and a transceiver, and wherein the RF signal transmitted back from the one or more frequency identification tags is picked up by the RF reader'"'"'s antenna and passed onto a transceiver.

13. A method for obtaining information concerning an implant, comprising:

acquiring positional information from a subject having one or more implants with at least one screw having an RFID-tag affixed thereto, the positional information including the axial position of the screw relative to the implant;

placing the subject in proximity to an RF reader;

acquiring current positional information of the RFID-tagged implant; and

comparing the current information of the RFID-tagged implant to the acquired positional information.

14. The method of claim 13, wherein the at least one RFID tag is affixed on or near the head of the screw.

15. The method of claim 13, wherein the at least one RFID tag is passive and employs a frequency having a propagation characteristics conducive to the transmission of radio signals within the human body.

16. The method of claim 13, wherein the at least one RFID tag is encased in glass.

17. The method of claim 13, wherein the at least one RFID tag transmits data to a reader that is part of a wireless fidelity network.

18. The method of claim 17, wherein the reader that is part of a wireless fidelity network is selected from a group consisting of a desk computer, a hand-held computer, a personal digital assistant, and combinations thereof.

19. The method of claim 17, wherein the RF reader is a member of a mesh network that includes multiple sensors employing micro-electro-mechanical systems (MEMS).

20. An apparatus for obtaining information concerning the status of an implant, comprising:

one or more surgical implants and one or more corresponding fasteners, at least one of the fasteners being tagged with one or more radio frequency identification tags storing positional information including an axial position of at least one of the fasteners relative to the one or more surgical implants;

a reader device capable of transmitting a signal to and receiving a signal from the one or more radio frequency identification tags a in a wireless radio frequency field;

a database connected to the reader device for storing information about the one or more tagged fasteners; and

a data decoder that compares data received by the reader device from the radio frequency identification tags of the fasteners to the database.

21. The apparatus of claim 20, wherein the one or more radio frequency identification tags are activated by an RF field transmitted by the reader device.

22. The apparatus of claim 20, wherein the reader device comprises an antenna that receives an RF signal from the one or more radio frequency identification tags and passes the signal onto a transceiver.

23. The apparatus of claim 20, wherein the one or more RFID tags affixed to the one or more implants are encased in glass.

24. The apparatus of claim 20, wherein the reader device is connected to one or more components selected from a group consisting of a desk computer, a hand-held computer, a personal digital assistant, and combinations thereof.

25. The apparatus of claim 20, wherein the reader device is a member of a mesh network.

26. The apparatus of claim 20, wherein the reader device transmits radio frequency signals based upon propagating electromagnetic waves.

27. An apparatus for obtaining information concerning the position of an orthopedic implant, comprising:

one or more RFID-tagged screws positioned in one or more implants;

a calculator for acquiring relative axial positional information of the RFID-tagged screw positioned in the one or more implants;

a memory for storing positional information of the one or more RFID-tagged implants;

an RF reader placed in proximity to the one or more tagged implants for acquiring current positional data; and

a data decoder for comparing the current positional information of the RFID-tagged implant to data in the memory.

28. The apparatus of claim 27, wherein the RF reader is selected from one or more of the group consisting of a fixed, wired and wireless reader.

29. The apparatus of claim 27, wherein the RF reader is a part of a wireless fidelity local area network.

30. The apparatus of claim 27, wherein the RF reader is connected to one or more of a group consisting of a desk-top computer, a lap-top computer, a personal digital assistant, and a sub-notebook.

31. The apparatus of claim 27, wherein the reader device is a member of a mesh network.