Bone registration methods for robotic surgical procedures

Patent metadata

Field	Value
Publication number	US-12433679-B2
Application number	US-202218076541-A
Country	US
Kind code	B2
Filing date	Dec 7, 2022
Priority date	Apr 1, 2019
Publication date	Oct 7, 2025
Grant date	Oct 7, 2025

Abstract

A computer-implemented method to improve the point collection process during registration of a bone for a computer-assisted surgical procedure is provided. Based on bone digitization data, a simulation is performed to confirm the accuracy of the registration for different digitization regions. Results are tested to identify which digitization regions meet a predefined accuracy requirement. The resulting information is used to perform a computer-assisted surgical procedure. A computerized simulation method for registration of a bone for a computer-assisted surgical procedure is also provided based on processor executing random stroking an expected exposed surface of a bone model with multiple of stroke curves to cover most of the bone model surface with uniform noise and a random sample consensus is applied to remove outlying point to yield the best registration results, to find the top subset as to overlap. A method to perform computer-assisted surgery is also provided.

First claim

The invention claimed is:

1. A computerized method for evaluating registration accuracy for different digitization regions on a bone model, the method comprising:
determining a first plurality of simulated registration points relative to a first digitization region on the bone model;
performing a first registration registering locations of the first plurality of simulated registration points to locations of a first plurality of predetermined registration points on a surface of the bone model;
determining a first accuracy of the first registration;
determining a second plurality of simulated registration points relative to a second digitization region on the bone model, wherein the first digitization region is different than the second digitization region;
performing a second registration registering locations of the second plurality of simulated registration points to locations of a second plurality of predetermined registration points on a surface of the bone model;
determining a second accuracy of the second registration; and
comparing the first accuracy and the second accuracy.

2. The method of claim 1 wherein the bone model is a patient-specific bone model, a cadaveric bone model, or a set of historical patient-specific bone models.

3. The method of claim 1 further comprising determining if the first accuracy or the second accuracy meets a predefined registration accuracy.

4. The method of claim 3 wherein the predefined registration accuracy is determined using translational errors and rotational errors, wherein the translational errors includes medial/lateral, proximal/distal and anterior/posterior errors and the rotational errors includes flexion/extension, valgus/varus, and internal/external errors.

5. The method of claim 1 wherein the bone model is a femoral bone model or a tibial bone model.

6. The method of claim 1 wherein the first registration is repeated for different positions and orientation (POSEs) of the surface of the bone model with respect to the locations of the first plurality of simulated registration points.

7. The method of claim 6 wherein the different POSEs for the surface of the bone model comprises rotation angles limited to −179 degrees to 180 degrees about all three coordinate axes (X, Y, Z) of the bone model, and translational movement limited to +/−500 mm with respect to a base coordinate system.

8. The method of claim 1 wherein the locations for the first plurality of simulated registration points is determined by adding random noise to the first plurality of predetermined registration points.

9. The method of claim 8 wherein the random noise simulates uncertainty introduced by a user when digitizing one or more of the first plurality of predetermined registration points.

10. The method of claim 8 wherein adding random noise to each of the first plurality of predetermined registration points comprises moving a predetermined registration point on a plane perpendicular to a first vector to a point 2 , determining a point 3 on the surface of the bone model closest to point 2 , moving point 3 along a second vector to point 4 , wherein the location of point 4 is a location for a simulated registration point from the first plurality of simulated registration points.

11. The computerized method of claim 1 further comprising:
determining a third plurality of simulated registration points relative to a third digitization region on the bone model, wherein the performing of the first registration further comprises registering locations of the third plurality of simulated registration points to locations of a third plurality of predetermined registration points on the surface of the bone model; and
determining a fourth plurality of simulated registration points relative to a fourth digitization region on the bone model, wherein the performing of the second registration further comprises registering locations of the fourth plurality of simulated registration points to locations of a fourth plurality of predetermined registration points on the surface of the bone model.

12. The computerized method of claim 1 further comprising storing the location of the first digitization region relative to the bone model for use to register the bone model to a bone.

13. A computerized method for evaluating registration accuracy for different digitization regions on a bone model, the method comprising:
determining a first plurality of simulated registration points relative to a first set of digitization regions on the bone model;
performing a first registration registering locations of the first plurality of simulated registration points to locations of a first plurality of predetermined registration points on a surface of the bone model;
determining a first accuracy of the first registration;
determining a second plurality of simulated registration points relative to a set of second digitization region on the bone model, wherein at least one digitization region in the second set of digitization regions is different than at least one digitization region in the first set of digitization regions;
performing a second registration registering locations of the second plurality of simulated registration points to locations of a second plurality of predetermined registration points on a surface of the bone model;
determining a second accuracy of the second registration; and
comparing the first accuracy and the second accuracy.

14. The method of claim 13 wherein the bone model is a patient-specific bone model, a cadaveric bone model, or a set of historical patient-specific bone models.

15. The method of claim 13 further comprising determining if the first accuracy or the second accuracy meets a predefined registration accuracy.

16. The method of claim 13 wherein the locations for the first plurality of simulated registration points is determined by adding random noise to the first plurality of predetermined registration points.

17. The method of claim 16 wherein the random noise simulates uncertainty introduced by a user when digitizing one or more of the first plurality of predetermined registration points.

18. The method of claim 13 wherein the first registration is repeated for different positions and orientation (POSEs) of the surface of the bone model with respect to the locations of the first plurality of simulated registration points.

19. The method of claim 13 wherein the bone model is a femoral bone model or a tibial bone model.

20. The computerized method of claim 13 further comprising storing the location of the first set of digitization regions relative to the bone model for use to register the bone model to a bone.

Assignees

• Think Surgical Inc

Inventors

• Tan Yiyong
• Hanson Randall
• Gummalla Aruna

Classifications

• A61B2034/105

  Modelling of the patient, e.g. for ligaments or bones · CPC title

• A61B2034/252

  indicating steps of a surgical procedure · CPC title

• A61B2090/3762

  using computed tomography systems [CT] · CPC title

• A61B2090/364

  Correlation of different images or relation of image positions in respect to the body · CPC title

• A61B17/1675

  for the knee · CPC title