Method for producing a customised orthopaedic implant

Abstract

A customised orthopaedic implant is provided, the implant being formed of metal, the implant being substantially comprised of a lattice-type geometry that has a periodic arrangement and is conformal to a configuration of a region of bone that was resected to remove bone that is diseased and is optimised to substantially restore a biomechanical function of a bone from which the region of bone was resected on implantation of the customised orthopaedic implant in consideration of the anatomical function and of the properties of a bone type corresponding to the region of bone that was resected, together with patient-specific parameters and anticipated loads to which the implant will be subjected during various typical activities and movements.

The claims defining the invention are as follows: 
     
         1 . A customised orthopaedic implant formed of metal, the implant formed by a method comprising the following steps:
 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 topologically 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 is optimised to substantially restore the biomechanical function of the bone 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 customised orthopaedic implant according to  claim 1 , wherein a 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. 
     
     
         3 . A customised orthopaedic implant according to  claim 1 , wherein said implant is manufactured using additive technology. 
     
     
         4 . A customised orthopaedic implant according to  claim 3 , wherein the step of manufacturing using additive technology involves selective laser melting. 
     
     
         5 . A customised orthopaedic implant according to  claim 3 , wherein said implant is optimised to meet additive manufacturing constraints. 
     
     
         6 . A customised orthopaedic implant according to  claim 1 , wherein the diseased region of bone is affected by osteosarcoma. 
     
     
         7 . 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. 
     
     
         8 . A customised orthopaedic implant formed of metal, the implant being substantially comprised of a lattice-type geometry that has a periodic arrangement and is conformal to a configuration of a region of bone that was resected to remove bone that is diseased and is optimised to substantially restore a biomechanical function of a bone from which the region of bone was resected on implantation of the customised orthopaedic implant in consideration of the anatomical function and of the properties of a bone type corresponding to the region of bone that was resected, together with patient-specific parameters and anticipated loads to which the implant will be subjected during various typical activities and movements. 
     
     
         9 . A customised orthopaedic implant according to  claim 8 , wherein a porosity of the lattice-type geometry is varied at a region of the implant configured to interface with a volume of bone remaining after the region of bone has been resected to remove bone that is diseased so as to enhance bone ingrowth. 
     
     
         10 . A customised orthopaedic implant according to  claim 8 , wherein said implant is optimised to meet additive manufacturing constraints. 
     
     
         11 . A customised orthopaedic implant according to  claim 8 , wherein said implant is manufactured using additive technology. 
     
     
         12 . A customised orthopaedic implant according to  claim 11 , wherein manufacturing using additive technology involves selective laser melting.