METHODS FOR PATIENT-SPECIFIC SHOULDER ARTHROPLASTY

• US 20160157937A1
• Filed: 02/17/2016
• Published: 06/09/2016
• Est. Priority Date: 10/27/2011
• Status: Active Grant

• Current Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Inventors: Kehres, Clinton E., Hartman, William
• Granted Patent: US 10,426,549 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 17/1684 for the shoulder
• CPC Class Codes: A61B 17/1703 using imaging means, e.g. by X-rays
• CPC Class Codes: A61B 17/1739 specially adapted for particular parts of the body
• CPC Class Codes: A61B 17/1778 for the shoulder
• CPC Class Codes: A61B 2017/568 produced with shape and dimensions specific for an individual patient
• CPC Class Codes: A61B 2034/102 Modelling of surgical devices, implants or prosthesis
• CPC Class Codes: A61B 2034/108 Computer aided selection or customisation of medical implants or cutting guides
• CPC Class Codes: A61B 34/10 Computer-aided planning, simulation or modelling of surgical operations
• CPC Class Codes: A61F 2/4081 Glenoid components, e.g. cups

Abstract

A method of determining an optimal position of a glenoid implant. The method includes identifying a center point of a patient'"'"'s glenoid fossa based on an image of the patient'"'"'s glenoid fossa; determining the optimal position of the glenoid implant based on the location of the center point relative to a medial point of the patient'"'"'s scapula; and selecting orientation of an alignment pin based on the determined optimal glenoid implant position such that the glenoid fossa will be prepared to receive the glenoid implant at the optimal position when the glenoid fossa is prepared with a cutting device or guide coupled to the alignment pin.

Claims

1-20. -20. (canceled)

21. A method of determining a desired implantation position of a glenoid implant comprising:

identifying a center point of a glenoid fossa on a virtual model of a patient'"'"'s scapula using software run by a processor, the software identifying the center point using a best fit circle referenced off of three or more points of the glenoid fossa, at least the center point is visually displayed on the virtual model and the virtual model is created from an anatomical image of a patient'"'"'s scapula;

determining the desired implantation position of the glenoid implant as a line that passes through both the center point and a medial point of the virtual model of the patient'"'"'s scapula identified using the software; and

selecting an orientation of a virtual alignment pin using the software and visually displaying the orientation of the virtual alignment pin on the virtual model relative to the determined desired implantation position.

22. The method of claim 21, further comprising determining a version of the glenoid implant based on the location of the center point relative to a most medial point of the scapula.

23. The method of claim 22, wherein the version of the glenoid implant is determined based on a linear line extending from the center point toward the most medial point of the scapula identified using the software, the linear line visually displayed on the virtual model.

24. The method of claim 23, wherein the virtual alignment pin is oriented about 8°

inferior to the line.

25. The method of claim 23, further comprising designing a virtual guide customized to the glenoid fossa, the virtual guide including a receptacle configured to orient the virtual alignment pin relative to the linear line.

26. The method of claim 25, further comprising:

fabricating an alignment guide based upon the designed virtual guide customized to the patient'"'"'s glenoid fossa;

connecting a reamer to a physical alignment pin; and

reaming a patient'"'"'s glenoid fossa, the physical alignment pin positioned according to an orientation assigned virtually using the software and corresponding to the orientation assigned to the virtual alignment pin, the alignment guide configured to guide the reamer to prepare the glenoid to receive the implant at a physical position corresponding to the desired position.

27. The method of claim 21, wherein the desired position of the glenoid implant is determined based on the location of the center point relative to a most medial portion of a glenoid vault.

28. The method of claim 21, wherein the desired position of the glenoid implant is determined based on the location of the center point relative to an axis normal to a surface that passes through the center point.

29. The method of claim 21, wherein the desired position of the glenoid implant is determined based on the location of the center point relative to an inner cortex of the scapula.

30. The method of claim 21, further comprising:

determining the desired position assuming the glenoid implant is a reverse glenoid implant; and

orienting the virtual alignment pin at a tilt of about 18°

inferior to the line.

31. The method of claim 21, further comprising inserting a surgical alignment pin into the patient'"'"'s scapula, the surgical alignment pin positioned according to an orientation assigned virtually using the software and corresponding to the orientation assigned to the virtual alignment pin.

32. The method of claim 21, wherein the at least three points comprise three equally spaced points located at three of the following:

an anterior rim, a posterior rim, a superior rim, and an inferior rim.

33. A method of determining a desired implantation position of a glenoid implant comprising:

providing software run with a processor to create a virtual three-dimensional model of a scapula created from an anatomical image of a patient'"'"'s scapula;

identifying a center point of a glenoid fossa on the virtual three-dimensional model using the software, the software identifying the center point using a best fit circle referenced off of three or more points at a rim of the glenoid fossa, at least the center point is visually displayed on the virtual three-dimensional model;

determining the desired implantation position of the glenoid implant as a linear line extending between the center point and a most medial surface of the virtual model of the patient'"'"'s scapula identified using the software, wherein the linear line is visually displayed on the virtual three-dimensional model; and

selecting an orientation of a virtual alignment pin using the software and visually displaying the orientation of the virtual alignment pin on the virtual three-dimensional model at an angle from the desired implantation position.

34. The method of claim 33, wherein the angle of the virtual alignment pin is about 8°

inferior to the linear line.

35. The method of claim 33, further comprising determining an inclination of the glenoid fossa by orienting the virtual alignment pin perpendicular to a second line that extends between the inferior rim of the glenoid fossa and the superior rim of the glenoid fossa, wherein the second line is visually displayed on the three-dimensional model.

36. The method of claim 33, further comprising inserting a surgical alignment pin into the patient'"'"'s scapula, the surgical alignment pin positioned according to an orientation assigned virtually using the software and corresponding to the orientation assigned to the virtual alignment pin.

37. The method of claim 33, wherein, the at least three points comprise three equally spaced points located at three of the following:

an anterior rim, a posterior rim, a superior rim, and an inferior rim.

38. A method of determining a desired implantation position of a glenoid implant comprising:

determining the desired implantation position of the glenoid implant as a linear line extending between a first point and a second point of a virtual three-dimensional model of the patient'"'"'s scapula identified using software run by a processor, the linear line is visually displayed on the virtual three-dimensional model;

selecting an orientation of a virtual alignment pin using the software and visually displaying the orientation of the virtual alignment pin on the virtual three-dimensional model relative to the determined desired implantation position; and

inserting a surgical alignment pin into the patient'"'"'s scapula, the surgical alignment pin positioned according to an orientation assigned virtually using the software and corresponding to the orientation assigned to the virtual alignment pin.

39. The method of claim 38, further comprising:

fabricating a custom guide having a patient-specific surface that is formed as a negative of the patient'"'"'s glenoid fossa;

preparing the patient'"'"'s glenoid fossa to receive the glenoid implant by connecting a reamer to the surgical alignment pin; and

reaming the glenoid fossa, the surgical alignment pin guides the reamer such that the glenoid implant will provide predetermined glenoid version when connected to the patient'"'"'s glenoid fossa.

40. The method of claim 38, wherein one of the first and second points comprises a center point of the glenoid fossa identified on the virtual model, the software identifying the center point using a best fit circle referenced off of the rim of the glenoid fossa, at least the center point is visually displayed on the virtual three-dimensional model and the virtual three-dimensional model is created from an anatomical image of a patient'"'"'s scapula.