Preoperatively planning an arthroplasty procedure and generating a corresponding patient specific arthroplasty resection guide

Patent metadata

Field	Value
Publication number	US-9782226-B2
Application number	US-201314084255-A
Country	US
Kind code	B2
Filing date	Nov 19, 2013
Priority date	Dec 18, 2007
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

Methods of manufacturing a custom arthroplasty resection guide or jig are disclosed herein. For example, one method may include: generating MRI knee coil two dimensional images, wherein the knee coil images include a knee region of a patient; generating MRI body coil two dimensional images, wherein the body coil images include a hip region of the patient, the knee region of the patient and an ankle region of the patient; in the knee coil images, identifying first locations of knee landmarks; in the body coil images, identifying second locations of the knee landmarks; run a transformation with the first and second locations, causing the knee coil images and body coil images to generally correspond with each other with respect to location and orientation.

First claim

We claim:

1. A method of preoperatively planning an arthroplasty procedure in a computer environment, the method comprising:
a) access in the computer environment and via a network connection linked with a medical imaging system a first set of two dimensional medical images and a second set of two dimensional medical images, the first set of two dimensional images including a knee and at least one of a hip or ankle, the second set of two dimensional images including the knee, the first and second set of two dimensional medical images generated by the medical imaging system and being the result of separate medical imaging events, wherein the first set of two dimensional medical images includes a plurality of anatomical landmarks and the second set of two dimensional medical images also includes the plurality of anatomical landmarks;
b) locate first coordinate system points in the computer environment, the first coordinate system points approximating a knee center and at least one of a hip center or an ankle center, the locating of the first coordinate system points including an analysis of coronal two dimensional images of the first set of two dimensional medical images;
c) define in the computer environment a mechanical axis between the knee center and at least one of the hip center or the ankle center in the first set of two dimensional medical images;
d) locate in the computer environment first landmark references and second landmark references, the first landmark references locationally approximating the plurality of anatomical landmarks in the first set of two dimensional medical images, and the second landmark references locationally approximating the plurality of anatomical landmarks in the second set of two dimensional medical images;
e) computer generate a three dimensional knee computer model from the second set of two dimensional medical images; and
f) positionally matching the first and second landmark references so as to cause the three dimensional knee computer model and at least one of the defined mechanical axis or the first coordinate system points to be correlated relative to each other with respect to position and orientation in a global coordinate system of the computer environment.

2. The method of claim 1 , wherein the first landmark references include second coordinate system points in the computer environment and the second coordinate system points are employed with the first set of two dimensional medical images, and wherein the second landmark references include third coordinate system points in the computer environment and the third coordinate system points are employed with the second set of two dimensional medical images.

3. The method of claim 1 , wherein the first landmark references include second coordinate system points in the computer environment and the second coordinate system points are employed with the first set of two dimensional medical images, and wherein the second landmark references include third coordinate system points in the computer environment and the third coordinate system points are employed with the three dimensional knee computer model.

4. The method of claim 1 , wherein the first landmark references include first contours in the computer environment and the first contours are employed with the first set of two dimensional medical images, and wherein the second landmark references include second contours in the computer environment and the second contours are employed with the second set of two dimensional medical images.

5. The method of claim 4 , wherein at least one of the first contours or the second contours includes splines.

6. The method of claim 1 , wherein the first landmark references include first contours in the computer environment and the first contours are employed with the first set of two dimensional medical images, and wherein the second landmark references include second contours in the computer environment and the second contours are employed with the three dimensional knee computer model.

7. The method of claim 6 , wherein at least one of the first contours or the second contours includes splines.

8. The method of claim 1 , wherein the first landmark references include first image intensity variations in the first set of two dimensional medical images, and wherein the second landmark references include second image intensity variations in the second set of two dimensional medical images.

9. The method of claim 1 , wherein the first set of two dimensional medical images include body coil two dimensional images, and the second set of two dimensional medical images include knee coil two dimensional images.

10. The method of claim 9 , wherein the body coil two dimensional images encompasses at least patient hip, knee and ankle regions, and the knee coil two dimensional images encompasses at least the patient knee region, but not the patient ankle and hip regions.

11. The method of claim 9 , wherein the body coil two dimensional images are MRI body coil images, and the knee coil two dimensional images are MRI knee coil images.

12. The method of claim 1 , wherein the second set of two dimensional medical images includes a greater number of coronal images slices than the first set of two dimensional medical images.

13. The method of claim 1 , wherein the second set of two dimensional medical images includes a greater number of sagittal image slices than the first set of two dimensional medical images.

14. The method of claim 1 , wherein the second set of two dimensional medical images includes a greater number of axial image slices than the first set of two dimensional medical images.

15. The method of claim 1 , further comprising defining a resection plane parallel to, and offset a distance along the mechanical axis from, a reference plane that:
1) is orthogonal to the mechanical axis in a coronal view and
2) extends through a condylar point on the three dimensional knee computer model, wherein the condylar point is either a most distal femoral condyle point or a tibial condyle point.

16. A method of manufacturing a custom arthroplasty resection guide according to the method of claim 15 , further comprising: manufacture the custom arthroplasty resection guide by using data associated with the resection plane to define a resection guide in the custom arthroplasty resection guide.

17. The method of claim 1 , wherein the first landmark references and second landmark references are in a knee region.

18. The method of claim 1 , wherein the positionally matching the first and second landmark references employs an Iterative Closest Point algorithm or gradient descent optimization.

19. The method of claim 1 , wherein the three dimensional computer knee model includes at least one of a computer model of a distal femur region or a proximal tibia region.

20. The method of claim 1 , wherein the positionally matching the first and second landmark references causes at least one of the second set of two dimensional medical images or the three dimensional computer knee model to reposition in the global coordinate system to the location and orientation of the first set of two dimensional medical images.

21. The method of claim 1 , wherein the three dimensional computer knee model includes a three dimensional computer femur bone model and the mechanical axis is a femoral mechanical axis.

22. The method of claim 1 , wherein the three dimensional computer knee model includes a three dimensional computer tibia bone model and the mechani

Assignees

• Howmedica Osteonics Corp

Inventors

• Park Ilwhan
• Song keun
• Mishin Oleg
• Santarella Michael

Classifications

• G06F18/22

  Matching criteria, e.g. proximity measures · CPC title

• A61B17/122

  Clamps or clips, e.g. for the umbilical cord {(for the vas deferens A61F6/206)} · CPC title

• G06V10/751

  Comparing pixel values or logical combinations thereof, or feature values having positional relevance, e.g. template matching · CPC title

• A61F2002/4633

  for selection of endoprosthetic joints or for pre-operative planning · CPC title

• A61B17/1675

  for the knee · CPC title