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EP-4013333-B1 - PRE-OPERATIVE PLANNING OF SURGICAL REVISION PROCEDURES FOR ORTHOPEDIC JOINTS

EP4013333B1EP 4013333 B1EP4013333 B1EP 4013333B1EP-4013333-B1

Inventors

  • CHAOUI, JEAN
  • MAYYA, Maximilien

Dates

Publication Date
20260506
Application Date
20200814

Claims (15)

  1. A method comprising: obtaining, by a computing system, image data of a joint of a patient that includes an implant, wherein the image data comprises a three-dimensional (3D) model of the joint with the implant; in the 3D model of the joint with the implant, identifying voxels that correspond to a bone; based on the voxels identified as corresponding to the bone, determining an initial shape estimate (900) for the bone; characterized in that the method comprises: determining a shape model (106, 902) for a morbid anatomical object; aligning the initial shape estimate to the shape model to form an aligned initial shape estimate; and deforming the shape model based on the aligned initial shape estimate to generate a pre-implant, morbid approximation (1000, 2912) of the bone.
  2. The method of claim 1, further comprising: outputting the pre-implant, morbid approximation of the bone to a display device.
  3. The method of claim 1 or 2, further comprising: in the 3D model of the joint with the implant, identifying voxels that correspond to the implant; removing the voxels that correspond to the implant from the 3D model of the joint with the implant to generate a 3D model of the joint without the implant; and optionally further comprising: outputting the 3D model of the joint without the implant to a display device.
  4. The method of claim 3, further comprising: segmenting the 3D model of the joint without the implant based on the pre-implant, morbid approximation of the bone; and optionally wherein segmenting the 3D model of the joint without the implant based on the pre-implant, morbid approximation of the bone comprises inputting the pre-implant, morbid approximation of the bone into a machine learning system.
  5. The method of claim 4, further comprising: outputting the segmented 3D model of the joint without the implant; and optionally wherein outputting the segmented 3D model of the joint without the implant comprises outputting a plurality of possible segmentations for the 3D model of the joint without the implant; or optionally further comprising: outputting a confidence value for the plurality of possible segmentations for the 3D model of the joint without the implant.
  6. The method of any of claims 1-3, further comprising: in the 3D model of the joint with the implant, identifying voxels that correspond to non-implant features; removing the voxels that correspond to the non-implant features from the 3D model of the joint with the implant to generate a 3D model of the implant; and optionally further comprising: outputting the 3D model of the implant to a display device.
  7. The method of claim 1, further comprising: in the 3D model of the joint with the implant, identifying voxels that correspond to the implant to determine a 3D model of the implant; based on the 3D model of the implant, determining one or more features for the implant; and aligning the initial shape estimate to the shape model to form the aligned initial shape estimate based on the determined one or more features for the implant; and optionally wherein aligning the initial shape estimate to the shape model further comprises performing an initial alignment of the initial shape estimate to the shape model and rotating the initial shape estimate relative to the shape model.
  8. The method of claim 1, wherein determining the shape model for the morbid anatomical object comprises receiving a classification of a pre-implant, morbid bone of the patient from a user.
  9. The method of claim 1, wherein identifying the voxels that correspond to bone comprises: classifying voxels in the 3D model as corresponding to one of bone, implant, soft tissue, or noise.
  10. The method of any of claims 1-9, wherein deforming the shape model based on the aligned initial shape estimate comprises performing one or both of iterative closest point registration or elastic registration; and/or wherein the image data comprises computed tomography (CT) images.
  11. A device comprising: a memory (104); and one or more processors implemented in circuitry (102) and configured to: obtain image data of a joint of a patient that includes an implant, wherein the image data comprises a three-dimensional (3D) model of the joint with the implant; in the 3D model of the joint with the implant, identify voxels that correspond to a bone; based on the voxels identified as corresponding to the bone, determine an initial shape estimate for the bone; characterized in that the one or more processors are configured to: determine a shape model (106, 902) for a morbid anatomical object; align the initial shape estimate (900) to the shape model (106, 902) to form an aligned initial shape estimate; and deform the shape model based on the aligned initial shape estimate to generate a pre-implant, morbid approximation of the bone.
  12. The device of claim 11, wherein the one or more processors are further configured to: in the 3D model of the joint with the implant, identify voxels that correspond to the implant; remove the voxels that correspond to the implant from the 3D model of the joint with the implant to generate a 3D model of the joint without the implant; and optionally wherein the one or more processors are further configured to: output the 3D model of the joint without the implant to a display device (112, 118).
  13. The device of claim 12, wherein the one or more processors are further configured to: segment the 3D model of the joint without the implant based on the pre-implant, morbid approximation of the bone.
  14. The device of claim 11, wherein the one or more processors are further configured to: in the 3D model of the joint with the implant, identify voxels that correspond to the implant to determine a 3D model of the implant; based on the 3D model of the implant, determine one or more features for the implant; and align the initial shape estimate to the shape model to form the aligned initial shape estimate based on the determined one or more features for the implant; and optionally wherein to align the initial shape estimate to the shape model, the one or more processors are further configured to perform an initial alignment of the initial shape estimate to the shape model and rotate the initial shape estimate relative to the shape model.
  15. The device of any of claims 11-14, wherein to deform the shape model based on the aligned initial shape estimate, the one or more processors are further configured to perform one or both of iterative closest point registration or elastic registration; and/or wherein the image data comprises computed tomography (CT) images.

Description

This application claims the benefit of U.S. Provisional Patent Application 62/887,838, filed 16 August 2019. BACKGROUND Surgical joint repair procedures involve repair and/or replacement of a damaged or diseased joint. A surgical joint repair procedure, such as joint arthroplasty as an example, may involve replacing the damaged joint or a damaged implant with a prosthetic that is implanted into the patient's bone. Proper selection or design of a prosthetic that is appropriately sized and shaped and proper positioning of that prosthetic are important to ensure an optimal surgical outcome. A surgeon may analyze damaged bone to assist with prosthetic selection, design and/or positioning, as well as surgical steps to prepare bone or tissue to receive or interact with a prosthetic. US 2013/188848 A1 describes an automatic implant detection from image artifacts. WO 2009/106816 A1 describes a customised surgical apparatus. US 2012/192401 A1 describes a system and method for image segmentation. WO 2019/046579 A1 describes an intraoperative implant augmentation. Abler Daniel et al (Journal of shoulder and elbow surgery, Mosby, Amsterdam, NL, vol. 27, no. 10, 27. June 2018, pages 1800-1808) describes "A statistical shape model to predict the premorbid glenoid cavity". SUMMARY This disclosure describes techniques for determining a pre-implant, morbid approximation of a bone of an orthopedic joint in which one or more implant components have been placed. This disclosure also describes techniques determining a type of implant implanted into the orthopedic joint. According to one example, a method includes determining a shape model for a morbid anatomical object; obtaining, by a computing system, image data of a joint of a patient that includes an implant, wherein the image data comprises a 3D model of the joint with the implant; in the 3D model of the joint with the implant, identifying voxels that correspond to a bone; based on the voxels identified as corresponding to the bone, determining an initial shape estimate for the bone; aligning the initial shape estimate to the shape model to form an aligned initial shape estimate; and deforming the shape model based on the aligned initial shape estimate to generate a pre-implant, morbid approximation of the bone. According to another example, a method includes obtaining, by a computing system, image data of a joint of a patient that includes an implant, wherein the image data comprises a 3D model of the joint with the implant; identifying a first object in the 3D model, wherein the first object corresponds to a first component of the implant; determining a first vector based on the first object; identifying a second object in the 3D model, wherein the second object corresponds to a second component of the implant; determining a second vector based on the second object; determining a third vector that is normal to a plane defined by the first vector and the second vector; determining a patient coordinate system based on the first vector, the second vector, and the third vector; identifying an anatomical object in the 3D model; generating an initial aligned shape that initially aligns the anatomical object from the image data to a shape model based on the determined patient coordinate system; and generating information indicative of a morbid, pre-implant shape of the anatomical object based on the initial aligned shape. According to another example, a method includes obtaining, by a computing system, image data of a joint of a patient; determining, by the computing system, that the joint includes an existing implant; segmenting the image data of the joint; and generating an identification of a type for the existing implant. According to another example, a method includes obtaining, by a computing system, image data of a joint of a patient with an existing implant; identifying, by the computing system in the image data of the joint of the patient with the existing implant, an image of the existing implant; accessing, in a memory device, a database that associates a plurality of implant products with images for the plurality of implant products, each implant product of the plurality of implant products being associated with at least one image; and identifying, based on a comparison of the image of the existing implant to the images for the plurality of implant products, at least one implant product that corresponds to the existing implant. According to another example, a method includes obtaining, by a computing system, image data of a joint of a patient with an existing implant; identifying, by the computing system, portions of the image corresponding to cement affixing a portion of the existing implant to bone; based on the portions of the image corresponding to cement, determining a cement intensity for the joint of the patient with the existing implant; and generating an output based on the determined cement intensity. According to another example, a device includes a memor