SYSTEMS AND METHODS FOR IDENTIFYING LANDMARKS ON ORTHOPEDIC IMPLANTS

• US 20100152573A1
• Filed: 08/26/2009
• Published: 06/17/2010
• Est. Priority Date: 02/28/2007
• Status: Active Grant

• Current Assignee: Smith & Nephew Incorporated (Smith & Nephew PLC)
• Original Assignee: Smith & Nephew Incorporated (Smith & Nephew PLC)
• Inventors: Austin, Gene Edward, Grusin, Nathaniel K., Ritchey, Nicholas S., Rains, James K., Faber, Henry B., Schwägli, Tobias, Ricci, William M.
• Granted Patent: US 8,784,425 B2
• Time in Patent Office: Days
• US Class Current: 600/424
• CPC Class Codes: A61B 17/1707 using electromagnetic effects, e.g. with magnet and external sensors
• CPC Class Codes: A61B 17/1725 for applying transverse screws or pins through intramedullary nails or pins
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2034/2072 Reference field transducer attached to an instrument or patient
• CPC Class Codes: A61B 2090/0813 Accessories designed for easy sterilising, i.e. re-usable
• CPC Class Codes: A61B 5/05 Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves impedance plethysmography A61B5/0295; measuring movement of the entire body or parts thereof A61B5/11; detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof A61B5/24
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/062 using magnetic field
• CPC Class Codes: A61B 5/1127 using markers

Abstract

Systems (10, 110, 1010, 1110) for identifying landmarks (31, 131, 1028, 1128) on orthopedic implants (30, 130, 1024, 1124) are disclosed. The systems (10, 110, 1010, 1110) include a field generator (16, 116, 1016, 1116) for generating a magnetic field and an orthopedic implant (30, 130, 1024, 1124) located within the magnetic field. The implant (30, 130, 1024, 1124) includes at least one landmark (31, 131, 1028, 1128), an optional removable probe (1029, 1129) and a first magnetic sensor (32, 132, 1026, 1126). The systems (10, 110, 1010, 1110) further include a landmark identifier (18, 118, 1016, 1116) with an optional second magnetic sensor (20, 120, 1020, 1120) and a processor (12, 112, 1012, 1112) for comparing sensor data from the first sensor (32, 132, 1026,1126) and second sensor (20, 120, 1020, 1120) or data from the first sensor (32, 132, 1026,1126) and landmark identifier (18, 118, 1016, 1116) using the set distance to calculate the position of the landmark identifier (18, 118, 1016, 1116) relative to the at least one landmark (31, 131, 1028,1128). The disclosed systems (10, 110, 1010, 1110) allow for blind targeting of one or more landmarks (31, 131, 1028, 1128).

Claims

1. A system for identifying a landmark, the system comprising:

a field generator for generating a magnetic field;

an orthopedic implant located within the magnetic field, the orthopedic implant having at least one landmark and a longitudinal groove with a proximal end portion and a distal end portion;

a first magnetic sensor mounted to the orthopedic implant at the distal end portion of the longitudinal groove and spaced apart from the at least one landmark a set distance;

a landmark identifier; and

a processor for comparing sensor data from the first sensor that landmark identifier and using the set distance to calculate the position of the landmark identifier relative to the at least one landmark.

2. The system of claim 1, wherein the landmark is selected from the group consisting of a structure, a void, a boss, a channel, a detent, a flange, a groove, a member, a partition, a step, an aperture, a bore, a cavity, a dimple, a duct, a gap, a notch, an orifice, a passage, a slit, a hole, or a slot.

3. The system of claim 1, wherein the orthopedic implant is an intramedullary nail.

4. The system of claim 1, wherein the orthopedic implant has an outer surface, an inner surface forming a cannulation, and a wall there between, and the first magnetic sensor is mounted within the wall.

5. The system of claim 1, wherein the orthopedic implant further comprises a pocket and the first sensor is located within the pocket.

6. The system of claim 1, wherein the orthopedic implant further comprises a cover.

7. The system of claim 1, wherein the orthopedic implant further comprises a second opening adapted to receive a cover.

8. The system of claim 1, further comprising an insertion handle removably coupled to the orthopedic implant.

9. The system of claim 1, further comprising a monitor electrically coupled to the processor.

10. The system of claim 1, wherein the longitudinal groove is disposed along an outer surface of the implant.

11. The system of claim 1, wherein the orthopedic implant further comprises a cannulation, and the longitudinal groove is generally adjacent the cannulation.

12. The system of claim 11, further comprising a removable lead coupled to the first sensor.

13. The system of claim 1, wherein the landmark identifier comprises a drill sleeve.

14. The system of claim 1, wherein the landmark identifier further comprises a serrated tip.

15. The system of claim 1, wherein the processor provides feedback information to a user.

16. The system of claim 1, wherein the field generator and landmark identifier are disposed within a common handheld housing.

17. A method for identifying a landmark, the method comprising:

providing an orthopedic implant assembly having an orthopedic implant with a longitudinal groove and a removable lead having a magnetic sensor attached thereto situated within the longitudinal groove, the orthopedic implant having a proximal end portion, a distal end portion, and at least one landmark on the distal end portion;

implanting the orthopedic implant assembly in a patient;

installing transfixion elements in the proximal end portion;

identifying the at least one landmark using a landmark identifier;

installing a transfixion element in the at least one landmark in the distal end portion after first installing transfixion elements in the proximal end portion; and

removing the removable lead.

18. A graphical user interface, comprising:

a first portion indicating drill depth relative to an implant; and

a second portion indicating landmark identifier position relative to a landmark located on the implant.

19. A system for identifying a landmark, the system comprising:

a field generator for generating a magnetic field;

an orthopedic implant located within the magnetic field, the orthopedic implant having at least one landmark;

an insertion handle removably attached to the orthopedic implant;

a first magnetic sensor placed within the orthopedic implant at a distal end portion and spaced apart from the at least one landmark a set distance;

a landmark identifier; and

a processor for comparing sensor data from the first sensor and landmark identifier using the set distance to calculate the position of the landmark identifier relative to the at least one landmark, wherein the first magnetic sensor is coupled to the processor via the insertion handle.

20. The system of claim 19, wherein the field generator and landmark identifier are disposed within a common handheld housing.