Circular glenoid method for shoulder arthroplasty

1. A method of implanting a glenoid component having a concave articulating surface comprising:

accessing a scapula;

identifying an inferior glenoid circle center of the scapula by identifying an inferior point of a glenoid rim, identifying an anterior point of the glenoid rim, identifying a posterior point of the glenoid rim, and establishing a best fit circle based upon the identified inferior point, the identified anterior point, and the identified posterior point;

preparing a glenoid fossa of the scapula to receive the glenoid component;

selecting the glenoid component having the concave articulating surface; and

implanting the selected glenoid component based upon the identified inferior glenoid circle center in the prepared glenoid fossa.

2. The method of claim 1 , wherein selecting comprises:

selecting the glenoid component with a circular outer periphery.

3. The method of claim 2 , wherein the glenoid component includes a spherical articulating surface, the method further comprising:

aligning a nadir of the spherical articulating surface with the glenoid fossa based upon the identified inferior glenoid circle center.

4. The method of claim 3 , wherein implanting the selected glenoid component comprises:

implanting the selected glenoid component with the nadir aligned with the identified inferior glenoid circle center.

5. The method of claim 3 , wherein implanting the selected glenoid component comprises:

implanting the selected glenoid component with the nadir offset from the identified inferior glenoid circle center.

6. The method of claim 5 , wherein implanting the selected glenoid component comprises:

implanting the selected glenoid component with the nadir offset superiorly and posteriorly from the identified inferior glenoid circle center.

7. The method of claim 1 , wherein identifying the inferior glenoid circle center comprises:

obtaining an image of the scapula; and

using the obtained image to identify the inferior glenoid circle center.

8. The method of claim 7 , further comprising:

positioning a guide on the scapula based upon the obtained image.

9. The method of claim 8 , wherein positioning the guide comprises:

positioning the guide at the identified inferior glenoid circle center.

10. The method of claim 8 , wherein positioning the guide comprises:

positioning the guide at a location posterior and superior to the identified inferior glenoid circle center.

11. The method of claim 10 , wherein:

identifying the inferior point of the glenoid rim comprises identifying the most inferior point of the glenoid rim;

identifying the anterior point of the glenoid rim comprises identifying the most anterior point of the glenoid rim;

identifying the posterior point of the glenoid rim comprises identifying the most posterior point of the glenoid rim; and

establishing the best fit circle comprises establishing a bets fit circle based upon the identified most inferior point, the identified most anterior point, and the identified most posterior point.

12. The method of claim 1 , wherein:

identifying the inferior point of the glenoid rim comprises identifying the most inferior point of the glenoid rim;

identifying the anterior point of the glenoid rim comprises identifying the most anterior point of the glenoid rim;

identifying the posterior point of the glenoid rim comprises identifying the most posterior point of the glenoid rim; and

establishing the best fit circle comprises establishing a bets fit circle based upon the identified most inferior point, the identified most anterior point, and the identified most posterior point.

13. A method of implanting a glenoid component having a concave articulating surface comprising:

obtaining an image of a scapula;

identifying an inferior glenoid circle center of the scapula based upon the image by identifying an inferior point of a glenoid rim, identifying an anterior point of the glenoid rim, identifying a posterior point of the glenoid rim, and establishing a best fit circle based upon the identified inferior point, the identified anterior point, and the identified posterior point;

selecting the glenoid component having the concave articulating surface;

preparing a glenoid fossa of the scapula to receive a prosthesis; and

implanting the selected glenoid component in the prepared glenoid fossa based upon the identified inferior glenoid circle center.

14. The method of claim 13 , wherein selecting comprises:

selecting the glenoid component with a circular outer periphery.

15. The method of claim 13 , wherein the glenoid component includes a spherical articulating surface, the method further comprising:

aligning a nadir of the spherical articulating surface with the glenoid fossa based upon the identified inferior glenoid circle center.

16. The method of claim 15 , wherein implanting the selected glenoid component comprises:

implanting the selected glenoid component with the nadir aligned with the identified inferior glenoid circle center.

17. The method of claim 15 , wherein implanting the selected glenoid component comprises:

implanting the selected glenoid component with the nadir offset from the identified inferior glenoid circle center.

18. The method of claim 17 , wherein implanting the selected glenoid component comprises:

implanting the selected glenoid component with the nadir offset superiorly and posteriorly from the identified inferior glenoid circle center.

19. The method of claim 17 , further comprising:

identifying a spinning point of the scapula; and

determining an offset of the spinning point from the identified inferior glenoid circle center, wherein implanting the selected glenoid component comprises:

implanting the selected glenoid component with the nadir offset from the identified inferior glenoid circle center by the determined offset.

20. The method of claim 19 , further comprising:

positioning a guide on the scapula based upon the obtained image.