Method for producing a customised orthopaedic implant

Patent metadata

Field	Value
Publication number	US-10688726-B2
Application number	US-201515123024-A
Country	US
Kind code	B2
Filing date	Mar 4, 2015
Priority date	Mar 4, 2014
Publication date	Jun 23, 2020
Grant date	Jun 23, 2020

Abstract

A method for producing a customised orthopaedic implant is provided. The method involves scanning a bone from which a diseased region of bone will be resected to obtain a three dimensional digital image of an unresected volume of bone; scanning the bone after a diseased region of bone has been resected to obtain a corresponding three dimensional digital image of a resected volume of bone; and comparing the three dimensional digital image of the unresected volume of bone to the corresponding three dimensional digital image of the resected volume of bone to estimate a volume of bone that has been resected. The estimate of the volume of bone that has been resected is used to design a customised orthopaedic implant that substantially corresponds to the configuration of the resected volume of bone, the implant being configured to substantially restore a biomechanical function of the bone. Finally the customised orthopaedic implant is manufactured and provided for insertion into the resected region of bone.

First claim

The claims defining the invention are as follows:

1. A method for producing a customised orthopaedic implant formed of metal, the method comprising:
a. scanning a bone, the bone being a diseased bone from which a region of bone that is diseased is to be resected to obtain a three dimensional digital image of an unresected volume of the diseased bone;
b. resecting the region of bone that is diseased to leave a remaining volume of the bone from which the diseased region has been resected;
c. scanning the remaining volume of bone after the region of bone that is diseased has been resected to obtain a corresponding three dimensional digital image of the remaining volume of bone;
d. comparing the three dimensional digital image of the unresected volume of bone to the corresponding three dimensional digital image of the remaining volume of bone to estimate a volume of the region of bone that has been resected;
e. using the estimate of the volume of the region of bone that has been resected to generate a three dimensional computer model that substantially conforms to a configuration of the volume of the region of bone that was resected and is optimised to substantially restore a biomechanical function of the bone on implantation of a customised orthopaedic implant corresponding to the optimised three dimensional computer model; and
f. manufacturing the customised orthopaedic implant from the optimised three dimensional computer model, wherein the implant is configured for insertion into the region of the remaining bone from which the diseased region of bone has been resected in step b.
wherein the customised orthopaedic implant is substantially comprised of a lattice-type geometry that has a periodic arrangement and that is conformal to the resected volume of bone, and
wherein the optimisation to substantially restore the biomechanical function of the bone involves topological optimisation to provide the implant with an optimal conformal lattice-type geometry made in consideration of the anatomical function and of the properties of the bone type corresponding to the region of diseased bone that has been resected, together with patient-specific parameters and the anticipated loads to which the implant will be subjected during various typical activities and movements.

2. A method for producing a customised orthopaedic implant according to claim 1 , wherein the topological optimisation involves consideration of patient-specific maximum stress and deflection to which the bone type which corresponds to the bone will be subjected during said various typical activities and movements.

3. A method for producing a customised orthopaedic implant according to claim 1 , wherein the porosity of the lattice-type geometry is varied at a region of the implant configured to interface with the remaining volume of the bone so as to enhance bone ingrowth.

4. A method for producing a customised orthopaedic implant according to claim 1 , wherein said manufacture is conducted using additive technology.

5. A method for producing a customised orthopaedic implant according to claim 4 , wherein the additive technology involves selective laser melting.

6. A method for producing a customised orthopaedic implant according to claim 4 , wherein prior to said manufacturing, the optimised three dimensional computer model is assessed for suitability for additive manufacture, and if required, modified to meet additive manufacture constraints.

7. A method for producing a customised orthopaedic implant according to claim 6 , wherein said additive manufacture includes transmitting the three dimensional computer model to a three dimensional printer.

8. A method for producing a customised orthopaedic implant according to claim 1 , wherein the step of scanning to obtain a three dimensional digital image in steps a. and/or c. comprises obtaining a plurality of two dimensional digital images from which the respective three dimensional image is constructed.

9. A method for producing a customised orthopaedic implant according to claim 1 , wherein the diseased region of bone is affected by osteosarcoma.

10. A method for producing a customised orthopaedic implant according to claim 1 , wherein steps a. to f. occur consecutively during a period of time in which a patient is under anaesthesia.

Assignees

• Melbourne Inst Tech

Inventors

• Shidid Darpan
• Leary Martin
• Brandt Milan
• Choong Peter

Classifications

• A61F2250/0023

  differing in porosity · CPC title

• B29C64/153

  using layers of powder being selectively joined, e.g. by selective laser sintering or melting · CPC title

• B29L2031/7532

  Artificial members, protheses · CPC title

• A61F2/30942 Primary

  for designing or making customized prostheses, e.g. using templates, CT or NMR scans, finite-element analysis or CAD-CAM techniques · CPC title

• A61F2002/30948

  using computerized tomography, i.e. CT scans · CPC title