SYSTEMS AND METHODS FOR MEASURING PERFORMANCE PARAMETERS RELATED TO ORTHOPEDIC ARTHROPLASTY

• US 20160007909A1
• Filed: 09/21/2015
• Published: 01/14/2016
• Est. Priority Date: 03/20/2013
• Status: Active Grant

• Current Assignee: Mirus LLC
• Original Assignee: Polaris Surgical LLC
• Inventors: SINGH, Angad, FITZSIMONS, Philip Matthew
• Granted Patent: US 9,585,615 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 5/1121 Determining geometric values, e.g. centre of rotation or angular range of movement
• CPC Class Codes: A61B 5/1126 using a particular sensing technique
• CPC Class Codes: A61B 5/4585 Evaluating the knee
• CPC Class Codes: A61B 5/4851 Prosthesis assessment or monitoring
• 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 2002/4666 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61F 2002/4668 for measuring angles

Abstract

A knee balancing system for measuring performance parameters associated with an orthopedic articular joint comprises a force sensing module and one or more inertial measurement units. The force sensing module comprises a housing that includes an articular surface having a medial portion and a lateral portion, each of which is substantially mechanically isolated from the other. The force sensing module also includes first and second sets of sensors disposed within the housing. The first set of sensors is mechanically coupled to the medial portion of the articular surface and configured to detect information indicative of a first force incident upon the medial portion of the articular surface. The second set of sensors is mechanically coupled to the lateral portion of the articular surface and configured to detect information indicative of a second force incident upon a lateral portion of the articular surface. The inertial measurement unit is configured to detect information indicative of an orientation of at least one of a first bone and a second bone of a knee joint.

Claims

1. A computer-implemented method for tracking performance parameters associated with an orthopedic articular joint, the method comprising:

receiving, at a processor associated with a computer, first information indicative of a force detected at an articular interface between a first bone and a second bone of a patient;

receiving, at the processor, second information indicative of an orientation of at least one of the first bone and the second bone; and

estimating, by the processor, a location of a center of the force relative to a surface of the articular interface, the estimated location based, at least in part, on the first information;

estimating, by the processor, an orientation angle associated with at least one of the first bone and the second bone relative to a reference axis, the orientation angle based at least in part on the second information.

2. The method of claim 1, further comprising:

providing, by the processor, third information indicative of at least one of;

the estimated location of the center of the force relative to the surface of the articular interface or the orientation angle associated with the at least one of the first bone and the second bone relative to the reference axis;

estimating, by the processor, a magnitude at the location of the center of the force detected at the articular interface, the magnitude based, at least in part, on the first information; and

wherein the third information is further indicative of a magnitude of the force detected at the articular surface.

3. The method of claim 2, wherein receiving first information indicative of a force detected at the articular interface between the first and second bones of a patient includes:

receiving information indicative of a first force applied to a medial portion of the surface of the articular interface;

receiving information indicative of a second force applied to a lateral portion of the surface of the articular interface;

wherein the third information is indicative of at least one of;

a respective magnitude associated with each of the first force and the second force, a location of the first force relative to the medial portion of the surface of the articular interface, a location of the second force relative to the lateral portion of the surface of the articular interface, and an orientation angle associated with the at least one of the first bone and a second bone.

4. The method of claim 3, wherein providing third information includes causing display of information indicative of a respective magnitude associated with each of the first force and the second force, a location of the first force relative to the medial portion of the surface of the articular interface, and a location of the second force relative to the lateral portion of the surface of the articular interface.

5. The method of claim 4, wherein causing display of information indicative of a respective magnitude associated with each of the first force and the second force further includes causing display of information indicative of the respective magnitude associated with each of the first and second forces as a function of the orientation angle associated with the at least one of the first bone and the second bone.

6. The method of claim 1, wherein providing third information includes causing display of at least one of:

the estimated location of the force relative to the surface of the articular interface or the orientation angle associated with the at least one of the first bone and the second bone relative to the reference axis.

7. The method of claim 1, wherein receiving second information indicative of the orientation of at least one of the first bone and the second bone includes receiving information indicative of the rate of angular rotation of the at least one of the first bone and the second bone and information indicative of linear acceleration of the at least one of the first bone and the second bone, wherein estimating the orientation angle associated with at least one of the first bone and the second bone relative to a reference axis is based, at least in part, on the information indicative of the rate of rotation and the information indicative of the acceleration.

8. A force and orientation sensing system for measuring performance parameters associated with an orthopedic articular joint, comprising:

a force sensing module comprising;

a housing including an articular surface having a medial portion and a lateral portion, each of which is substantially mechanically isolated from the other;

a first set of sensors disposed within the housing, the first set of sensors being mechanically coupled to the medial portion of the articular surface and configured to detect information indicative of a first force incident upon the medial portion of the articular surface; and

a second set of sensors disposed within the housing, the second set of sensors being mechanically coupled to the lateral portion of the articular surface and configured to detect information indicative of a second force incident upon a lateral portion of the articular surface, and

an orientation sensing module comprising a first orientation sensor and a second orientation sensor, wherein the orientation sensing module is configured to detect, via the first and second orientation sensors, information indicative of an orientation of at least one bone associated with the articular joint.

10. The force and orientation sensing system of claim 8, further configured to estimate, based at least in part on the force values detected by the first set of sensors, a magnitude and a location of a center of force associated with the first force incident upon the medial portion of the articular surface.

14. The force and orientation sensing system of claim 8, wherein the second set of sensors includes a plurality of transducers, each transducer including:

a respective cantilever component at least a portion of which is configured to deform in response to the first force incident upon the lateral portion of the articular surface; and

a respective strain gauge coupled to the respective cantilever component and configured to measure the deformation in the respective cantilever component;

wherein at least a portion of each cantilever component associated with the plurality of transducers is mechanically supported at a proximal end by a central base component.

15. The force and orientation sensing system of claim 8, further comprising a wireless transceiver configured to wirelessly transmit the information indicative of the first and second forces to a remote processing module.

16. The force and orientation sensing system of claim 8, wherein at least one of the first and second orientation sensors is an inertial measurement unit.

35. The force and orientation sensing system of claim 8, wherein at least one of the first and second orientation sensors are located outside the articular joint.

36. The force and orientation sensing system of claim 8, wherein the inertial measurement unit is located outside the articular joint.

9. (canceled)

11. (canceled)

12. (canceled)

13. (canceled)

17. (canceled)

18. (canceled)

19. (canceled)

20. A knee balancing system for tracking performance parameters associated with an orthopedic articular joint that comprises an interface between a first bone and a second bone, the knee balancing sensing system comprising:

a force sensing module, at least a portion of which is configured for implantation within orthopedic articular joint, the force sensing module configured to detect information indicative of at least one force incident upon at least a portion of an articular surface of the force sensing module;

at least one inertial measurement unit configured to detect information indicative of an orientation of at least one of a first bone and a second bone;

a processing device, communicatively coupled to the force sensing module and the at least one inertial sensor and configured to;

estimate a location of the at least one force relative to the articular surface, the estimated location based, at least in part, on the information indicative of the at least one force incident upon the at least a portion of the articular surface of the force sensing module;

estimate an orientation angle associated with the at least one of the first bone and the second bone relative to a reference axis, the orientation angle, based, at least in part, on the information indicative of the orientation of the at least one of the first bone and the second bone; and

provide information indicative of at least one of;

the estimated location of the force relative to the surface of the articular interface or the orientation angle associated with the at least one of the first bone and the second bone relative to the reference axis.

21. The knee balancing system of claim 20, wherein the at least one inertial measurement unit is configured to detect an orientation angle of at least one of the first bone and the second bone.

22. The knee balancing system of claim 20, wherein

the force sensing module includes:

a first set of sensors that includes at least three transducers, each transducer configured to detect a respective force value associated with the first force incident upon the medial portion of the articular surface; and

a second set of sensors that includes at least three transducers, each transducer configured to detect a respective force value associated with the second force incident upon the lateral portion of the articular surface.

23. The knee balancing system of claim 22, wherein the processing device is further configured to:

estimate, based at least in part on the force values detected by the first set of sensors, a magnitude and a location of a center of force associated with the first force incident upon the medial portion of the articular surface; and

estimate, based at least in part on the force values detected by the second set of sensors, a magnitude and a location of a center of force associated with the second force incident upon the medial portion of the articular surface.

43. The knee balancing system of claim 20, comprising at least two inertial measurement units, wherein one of the at least two inertial measurement units is located outside of the articular joint.

24-34. -34. (canceled)

37. A system for determining the orientation of a joint comprising a first and second bone, comprising:

a first orientation sensor positioned within the joint;

a second orientation sensor positioned outside of the joint;

a processor associated with a computer configured to receive information from the first and second orientation sensors and determine an orientation angle of at least the first or second bone relative to the joint.

38. The system of claim 37, wherein at least one of the first and second orientation sensors is an inertial measurement unit.

39. The system of claim 37, wherein at least one of the first and second orientation sensors is a magnetometer.

40. The system of claim 37, further comprising a calibration fixture configured to provide a known relative orientation for calibration of the first and second orientation sensors.

41. The system of claim 37, further comprising a force detection sensor configured to detect at least one of a magnitude or direction of a force within the joint.

42. The system of claim 37, wherein the first and second orientation sensors are located on opposite sides of the joint, respectively.