3d printed trans-modular scaffolds for grafting applications in segmental bone defects

Patent metadata

Field	Value
Publication number	US-2018177597-A1
Application number	US-201715658992-A
Country	US
Kind code	A1
Filing date	Jul 25, 2017
Priority date	Jul 25, 2016
Publication date	Jun 28, 2018
Grant date	—

Abstract

A bone repair scaffold having two moduli that match those of the cancellous and cortical bone in a patient receiving a bone graft/implant. The bone repair scaffold possesses increased mechanical properties to sustain physiological loading and biologically active capability to facilitate bone fusion. The bone repair scaffold may be 3D-printed, which allows for a variety of scaffold designs and configurations. Pore size, interconnected porosity, shape, and modulus of the bone repair scaffold may be modified for different bone graft applications, whether it is used as filler for bone cancer resections or trauma, or as a fusion device in cases of surgery. Depending on the defect location of the bone shaft, the relative porosity of the scaffold may be modified to account for changes in cortical bone thickness. A method for treating a bone defect using the bone repair scaffold is also disclosed.

First claim

We claim:

1 . A bone repair scaffold, comprising an inner core and an outer core circumferentially engaging said inner core, said inner core having a first porosity and a first modulus, and said outer core having a second porosity and a second modulus, wherein said second porosity is lower than said first porosity, whereby said second modulus is greater than said first modulus.

2 . The bone repair scaffold of claim 1 , wherein said first modulus is similar to that of cancellous bone, and wherein said second modulus is similar to that of cortical bone.

3 . The bone repair scaffold of claim 1 , wherein said first porosity, said second porosity and a transition between said first and second porosities constitute a pattern that emulates the porosity pattern of bone.

4 . The bone repair scaffold of claim 1 , further comprising a plurality of horizontal conduits and a plurality of vertical conduits, so as to emulate the internal architecture of bone.

5 . The bone repair scaffold of claim 4 , wherein said plurality of horizontal conduits includes a first set of horizontal conduits within said inner core, and a second set of horizontal conduits within said outer core, wherein said horizontal conduits of said second set are smaller than said horizontal conduits of said first set.

6 . The bone repair scaffold of claim 4 , wherein said plurality of vertical conduits includes a first set of vertical conduits within said inner core, and a second set of vertical conduits within said outer core, wherein said vertical conduits of said second set are smaller than said vertical conduits of said first set.

7 . The bone repair scaffold of claim 1 , wherein said scaffold has a compressive failure rate that is 1.25 times that of an adult human femur.

8 . The bone repair scaffold of claim 1 , wherein said scaffold has a compressive stiffness that is 6.3 times that of an adult human femur.

9 . The bone repair scaffold of claim 1 , further comprising a first end, a second end opposite said first end, and at least one inserter guide configured to engage one of said first or second ends of said scaffold, whereby said at least one inserter guide facilitates fixation of said scaffold to a bone.

10 . The bone repair scaffold of claim 9 , wherein said at least one inserter guide includes projections having teeth extending outward therefrom, said teeth being configured to engage the bone.

11 . The bone repair scaffold of claim 1 , wherein said scaffold is combined with one or more of a material selected from the group consisting of autograft bone, allograft bone, and bone marrow cells.

12 . The bone repair scaffold of claim 1 , wherein said scaffold is fabricated from polylactic acid (PLA).

13 . The bone repair scaffold of claim 12 , wherein said scaffold is fabricated via 3D printing.

14 . The bone repair scaffold of claim 1 , wherein said scaffold is fabricated from a biocompatible material selected from the group consisting of polymers, metals, ceramics, and combinations thereof.

15 . A method for repairing a bone defect, the method including the steps of
fabricating a bone repair scaffold sized and shaped so as to fit in the bone defect, the bone repair scaffold having an inner core and an outer core circumferentially engaging the inner core, the inner core having a first porosity and a first modulus, and the outer core having a second porosity and a second modulus, wherein the second porosity is lower than the first porosity, whereby the second modulus is greater than the first modulus; and implanting the bone repair scaffold in the bone defect.

Assignees

• Stevens Institute Of Technology
• The Trustees Of The Stevens Institute Of Tech Y

Inventors

• Chung Rebecca
• Valdevit Antonio
• Kalyon Dilhan

Classifications

• A61L27/3847

  Bones · CPC title

• B33Y80/00

  Products made by additive manufacturing · CPC title

• A61L2300/412

  Tissue-regenerating or healing or proliferative agents · CPC title

• A61L27/3821

  Bone-forming cells, e.g. osteoblasts, osteocytes, osteoprogenitor cells · CPC title

• A61L2300/64

  Animal cells · CPC title