INSTRUMENTED ORTHOPAEDIC IMPLANT FOR IDENTIFYING A LANDMARK

• US 20100145337A1
• Filed: 02/28/2007
• Published: 06/10/2010
• 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: Morgan, Robert L., Wilson, Darren James, Janna, Sied W.
• Granted Patent: US 8,814,868 B2
• Time in Patent Office: Days
• US Class Current: 606/67
• 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 17/72 Intramedullary pins, nails or other devices A61B17/744 takes precedence
• CPC Class Codes: A61B 2090/397 electromagnetic other than visible, e.g. microwave
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis

Abstract

A system (110, 150) for targeting a landmark (114, 160) is disclosed. The system includes an instrumented medical implant (112, 152), a control circuit (118, 153), a power supply (120, 157), and a landmark identifier (122, 154). The instrumented medical implant (112, 152) has one or more landmarks (114, 160) and each landmark (114, 160) has a corresponding coil (116, 162). The control circuit (118, 153) is electrically connected to the corresponding coil (116, 162), and the power supply (120, 157) is electrically connected to the control circuit (118,153). The landmark identifier (122, 154) has a magnetic sensor (124, 155) for sensing the corresponding coil (116, 162).

Claims

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

a. an instrumented medical implant, the instrumented medical implant having at least one landmark, and the at least one landmark having at least one corresponding coil;

b. a control circuit electrically connected to the at least one corresponding coil;

c. a power supply electrically connected to the control circuit; and

d. a landmark identifier having a magnetic sensor for sensing the at least one corresponding coil.

2. The system according to claim 1, wherein the instrumented medical implant further comprises at least one other landmark.

3. The system according to claim 1, wherein the at least one landmark is an opening.

4. The system according to claim 1, wherein the instrumented medical implant is at least one of a bone plate, a bone screw, a bone peg, a bone staple, an intramedullary nail, an intramedullary nail cap, an intramedullary nail and plate combination, an interference screw, a hip replacement stem, a hip replacement femoral neck, a hip replacement femoral head, a hip replacement acetabular liner, a hip replacement acetabular shell, a knee replacement tibial tray, a knee replacement tibial tray liner, a knee replacement femoral component, a knee replacement tibial tray shaft extension, a knee replacement patellar implant, a knee replacement wedge, a trochlear groove implant, a femoral canal restrictor, a shoulder replacement humeral stem, a shoulder replacement glenoid component, a shoulder replacement humeral head, an elbow replacement humeral component, an elbow replacement radial component, an elbow replacement ulnar component, an ankle replacement tibial component, and an ankle replacement talar component.

5. The system according to claim 1, wherein the control circuit is an oscillator.

6. The system according to claim 1, wherein the control circuit is a multiplexer.

7. The system according to claim 1, wherein the power supply and control circuit are comprised of a single unit.

8. The system according to claim 1, wherein the power supply includes at least one of a capacitor, an inductive coupling, a battery, a mechanically driven power generation unit, a piezoelectric device, and an energy scavenging device.

9. The system according to claim 1, wherein the landmark identifier is selected from the group consisting of a drill guide, a drill sleeve, a drill, a drill nose, a drill barrel, a drill chuck, and a fixation element.

10. The system according to claim 1, wherein the magnetic sensor is selected from the group consisting of a Hall effect sensor, a fluxgate magnetic field sensor, an inductive coil sensor, and a magneto-resistive sensor.

11. The system according to claim 1, wherein the power supply is an electromagnetic field generating coil.

12. The system according to claim 1, wherein the instrumented medical implant further comprises at least one other corresponding coil.

13. The system according to claim 12, wherein the at least one other corresponding coil is generally orthogonal to the at least one corresponding coil.

14. The system according to claim 12, wherein a relationship between the at least one other corresponding coil and the at least one corresponding coil is selected from the group consisting of generally oblique, offset, coplanar, parallel, collinear, and transverse.

15. A method of targeting fasteners relative to an instrumented orthopaedic implant, the method comprising:

a. installing an instrumented orthopaedic implant relative to a bone, the instrumented orthopaedic implant having a first driver coil and a second driver coil, the second driver coil generally orthogonal to the first driver coil;

b. activating the first driver coil;

c. activating the second driver coil;

d. sensing the first driver coil and the second driver coil;

e. transducing the sensed driver coil data;

f. aligning a drill guide with the transduced driver coil data; and

g. drilling an opening through the bone and the instrumented orthopaedic implant.

16. The method of claim 15, installing a fastener through the drilled opening.

17. The method of claim 15, wherein the instrumented orthopaedic implant is an intramedullary nail.

18. The method of claim 15, further comprising the step of affixing a portion of the instrumented orthopaedic implant manually.

19. The method of claim 15, further comprising the step of recording the sensor signals.

20. The method of claim 15, further comprising the step of activating at least one visual indicator.

21. The method of claim 20, wherein the at least one visual indicator is a light emitting diode.

22. A method of targeting a landmark relative to an instrumented orthopaedic implant, the instrumented orthopaedic implant having at least one landmark and at least one corresponding coil proximate to the at least one landmark, the method comprising:

a) inductively powering the instrumented orthopaedic implant;

b) energizing the at least one corresponding coil;

c) orienting a landmark identifier relative to the energized at least one corresponding coil;

d) sensing the energized at least one corresponding coil;

e) processing the sensed at least one corresponding coil data to detect proximity of the landmark identifier relative to the energized at least one corresponding coil; and

f) providing a user with feedback information on the proximity of the landmark identifier relative to the energized at least one corresponding coil.

23. A system for processing accelerometer data, the system comprising:

a) an accelerometer for measuring a physiological acceleration parameter;

b) a first processor operatively connected to the accelerometer, the first processor configured to receive the acceleration parameter from the accelerometer and configured to output machine readable acceleration data, the machine readable acceleration data comprising time domain accelerometer data;

c) a power supply electrically connected to the first processor; and

d) a second processor configured to receive the machine readable acceleration data and transform the time domain accelerometer data into frequency domain accelerometer data, wherein the antenna used to transmit the accelerometer data is also the inductive coupling element used to power the first processor and the accelerometer.