Computer-Assisted Joint Replacement Surgery and Navigation Systems

• US 20130274633A1
• Filed: 04/12/2012
• Published: 10/17/2013
• Est. Priority Date: 04/12/2012
• Status: Active Grant

• Current Assignee: Intellijoint Surgical Inc.
• Original Assignee: Avenir Medical Inc.
• Inventors: Hladio, Andre Novomir, Fanson, Richard Tyler, Bakirtzian, Armen Garo
• Granted Patent: US 9,314,188 B2
• Time in Patent Office: Days
• US Class Current: 600/587
• CPC Class Codes: A61B 5/1072 measuring distances on the body, e.g. measuring length, height or thickness A61B5/1076 takes precedence
• CPC Class Codes: A61B 5/4887 Locating particular structures in or on the body

Abstract

The present invention generally relates to computer-assisted joint replacement surgery, and corresponding navigation systems. The systems and methods presented find particular use in performing hip replacement surgery. For example, in one embodiment, there is provided a system and method for: (a) measuring a pre-dislocation positional relationship between a patient'"'"'s pelvis and the patient'"'"'s femur; (b) performing a post-dislocation femoral registration of the femur; (c) tracking the position of the femur relative to the pelvis during a reduction procedure; (d) calculating a change in leg length and a change in offset, after the reduction procedure, based on the femoral registration and the pre-dislocation positional relationship between the pelvis and the femur; and (e) conveying the change in leg length and the change in offset.

Claims

1. A system for performing a computer-assisted hip replacement surgery, comprising:

a pelvis sensor unit configured to be coupled to a patient'"'"'s pelvis;

a broach sensor unit configured to be coupled to a broach;

a femur sensor unit configured to be coupled to the patient'"'"'s femur; and

a computer-readable storage medium having instructions executable, by at least one processing device,

(a) which when executed prior to a dislocation of the femur from the pelvis, wherein the pelvis sensor unit is coupled to the pelvis and the femur sensor unit is coupled to the femur, cause the processing device to measure a pre-dislocation positional relationship between the pelvis sensor unit and the femur sensor unit,

(b) and which when executed after the dislocation of the femur from the pelvis, wherein the broach sensor unit is coupled to the broach, the femur sensor unit is coupled to the femur, and the broach is inserted within the femur, cause the processing device to perform a femoral registration by measuring an orientation between the broach sensor unit and the femur sensor unit,

(c) and which when executed during a reduction procedure, wherein the pelvis sensor unit is coupled to the pelvis and the femur sensor unit is coupled to the femur, cause the processing device to display a fixed target frame and a track frame, wherein the track frame depicts a reduction orientation between the femur sensor unit and the pelvis sensor unit, and

(d) and which when executed after the femur has been positioned such that the track frame matches the target frame, cause the processing device to (1) measure a post-reduction translational distance between the pelvis sensor unit and the femur sensor unit and (2) calculate and display a change in leg length and a change in offset based the pre-dislocation positional relationship and the femoral registration.

2. The system of claim 1, wherein a coordinate system of the broach matches a coordinate system of the femur.

3. The system of claim 1, wherein the femur sensor unit includes an optical reader, and the pelvis sensor unit and the broach sensor unit include a beacon.

4. The system of claim 1, wherein the pelvis sensor unit and the broach sensor unit include an optical reader, and the femur sensor unit includes a beacon.

5. The system of claim 1, wherein the pre-dislocation positional relationship includes a translational component and an orientation component.

6. The system of claim 5, wherein the fixed target frame depicts the pre-dislocation orientation.

7. The system of claim 1, wherein the pre-dislocation positional relationship is defined by roll, pitch, yaw, and three perpendicular translational distances between the pelvis sensor unit relative to the femur sensor unit.

8. The system of claim 7, wherein the fixed target frame depicts the pre-dislocation roll, pitch, and yaw.

9. The system of claim 1, wherein the orientation between the broach sensor unit and the femur sensor unit is defined by three degrees of rotation.

10. The system of claim 1, wherein the computer-readable storage medium further includes instructions, which when executed, cause the processing device to calculate and display a change in anterior-posterior femur position based the pre-dislocation positional relationship and the femoral registration.

11. The system of claim 1, wherein the femoral registration defines a femoral coordinate system.

12. A computer-readable storage medium for performing a hip replacement surgery, comprising:

instructions executable by at least one processing device that, when executed, cause the processing device to

(a) measure a pre-dislocation positional relationship between a femur sensor unit coupled to the patient'"'"'s femur and a pelvis sensor unit coupled to the patient'"'"'s pelvis,

(b) perform a post-dislocation femoral registration by measuring an orientation between the femur sensor unit and a broach sensor unit coupled to a broach inserted within the patient'"'"'s femur,

(c) measure an orientation between the femur sensor unit and the pelvis sensor unit during a reduction procedure, and

(d) calculate a change in leg length and a change in offset, based on the pre-dislocation positional relationship and the femoral registration.

13. The computer-readable storage medium of claim 12, further comprising:

instructions executable by at least one processing device that, when executed, cause the processing device to

(e) convey the change in leg length and the change in offset.

14. A computer-readable storage medium for performing a hip replacement surgery, comprising:

instructions executable by at least one processing device that, when executed, cause the processing device to

(a) measure a pre-dislocation translational position and orientation between a pelvis sensor unit coupled to a patient'"'"'s pelvis and a femur sensor unit coupled to the patient'"'"'s femur,

(b) register the femur after the femur has been dislocated from the pelvis,

(c) display a graphic mapping the pre-dislocation orientation against a real-time orientation between the pelvis sensor unit and the femur sensor unit, during a reduction procedure, and

(d) calculate a change in leg length and a change in offset, after the reduction procedure, based on the pre-dislocation translational position and the registration of the femur.

15. The computer-readable storage medium of claim 14, further comprising:

instructions executable by at least one processing device that, when executed, cause the processing device to

(e) convey the change in leg length and the change in offset.

16. The computer-readable storage medium of claim 14, wherein the femur is registered by measuring an orientation between the femur sensor unit and a registration sensor unit coupled to a registration tool.

17. The computer-readable storage medium of claim 14, wherein the femur is registered by measuring an orientation between the femur sensor unit and a broach sensor unit coupled to a broach inserted within the patient'"'"'s femur.

18. A computer-readable storage medium for performing a hip replacement surgery, comprising:

instructions executable by at least one processing device that, when executed, cause the processing device to

(a) measure a pre-dislocation leg length and offset between a patient'"'"'s pelvis and the patient'"'"'s femur,

(b) register the femur after the femur has been dislocated from the pelvis,

(c) track the position of the femur relative to the pelvis during a reduction procedure, and

(d) calculate a change in leg length and a change in offset, after the reduction procedure, based on the registration of the femur and the pre-dislocation leg length and offset measurement.

19. The computer-readable storage medium of claim 18, further comprising:

instructions executable by at least one processing device that, when executed, cause the processing device to

(e) convey the change in leg length and the change in offset.

20. The computer-readable storage medium of claim 18, wherein the femur is registered by measuring an orientation between the femur and a registration tool.