Engineered Scaffolds for Intervertebral Disc Repair and Regeneration and for Articulating Joint Repair and Regeneration

• US 20080195211A1
• Filed: 10/29/2007
• Published: 08/14/2008
• Est. Priority Date: 10/30/2006
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Michigan (University of Michigan), Wisconsin Alumni Research Foundation (University of Wisconsin System)
• Original Assignee: Wisconsin Alumni Research Foundation (University of Wisconsin System)
• Inventors: Murphy, William L., Feinberg, Stephen E., Hollister, Scott J., Lin, Chia-Ying, LaMarca, Frank, Adox, James R.
• Granted Patent: US 8,275,594 B2
• Time in Patent Office: Days
• US Class Current: 623/17.16
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/2846 Support means for bone substitute or for bone graft implants, e.g. membranes or plates for covering bone defects nets or sleeves applied to surface of endoprostheses A61F2/30907; bone plates A61B17/80; bone regeneration in dental surgery A61C8/0006
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/30942 for designing or making customized prostheses, e.g. using templates, CT or NMR scans, finite-element analysis or CAD-CAM techniques
• CPC Class Codes: A61F 2/3662 Femoral shafts
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• CPC Class Codes: A61F 2002/2817 Bone stimulation by chemical reactions or by osteogenic or biological products for enhancing ossification, e.g. by bone morphogenetic or morphogenic proteins [BMP] or by transforming growth factors [TGF]
• CPC Class Codes: A61F 2002/30004 the prosthesis being made from materials having different values of a given property at different locations within the same prosthesis
• CPC Class Codes: A61F 2002/30014 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2002/30032 differing in absorbability or resorbability, i.e. in absorption or resorption time
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/3008 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30261 parallelepipedal
• CPC Class Codes: A61F 2002/30578 having apertures, e.g. for receiving fixation screws
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30599 stackable
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30761 : Support means for artificial cartilage, e.g. cartilage defect covering membranes
• CPC Class Codes: A61F 2002/30777 : Oblong apertures
• CPC Class Codes: A61F 2002/30785 : parallel
• CPC Class Codes: A61F 2002/30789 : perpendicular with respect to each other
• CPC Class Codes: A61F 2002/30838 : Microstructures
• CPC Class Codes: A61F 2002/30841 : Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30884 : Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
• CPC Class Codes: A61F 2002/30892 : parallel
• CPC Class Codes: A61F 2002/3092 : having an open-celled or open-pored structure
• CPC Class Codes: A61F 2002/30948 : using computerized tomography, i.e. CT scans
• CPC Class Codes: A61F 2002/30962 : using stereolithography
• CPC Class Codes: A61F 2002/30968 : Sintering
• CPC Class Codes: A61F 2002/3097 : using laser
• CPC Class Codes: A61F 2002/30991 : Mandibular components
• CPC Class Codes: A61F 2210/0004 : bioabsorbable
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2230/0082 : parallelepipedal
• CPC Class Codes: A61F 2250/0014 : having different values of a given property or geometrical feature, e.g. mechanical property or material property, at different locations within the same prosthesis
• CPC Class Codes: A61F 2250/0018 : differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0031 : made from both resorbable and non-resorbable prosthetic parts, e.g. adjacent parts
• CPC Class Codes: A61F 2250/0063 : Nested prosthetic parts
• CPC Class Codes: A61F 2250/0098 : radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61F 2310/00017 : Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 : Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/00293 : containing a phosphorus-containing compound, e.g. apatite
• CPC Class Codes: A61F 2310/00796 : Coating or prosthesis-covering structure made of a phosphorus-containing compound, e.g. hydroxy(l)apatite
• CPC Class Codes: A61F 2310/00976 : Coating or prosthesis-covering structure made of proteins or of polypeptides, e.g. of bone morphogenic proteins BMP or of transforming growth factors TGF
• CPC Class Codes: A61P 19/08 : for bone diseases, e.g. rachitism, Paget's disease
• CPC Class Codes: B33Y 50/00 : Data acquisition or data processing for additive manufacturing
• CPC Class Codes: B33Y 80/00 : Products made by additive manufacturing

Abstract

Methods for the engineering and preparation of intervertebral disc repair scaffolds and articulating joint repair scaffolds are disclosed. The methodology utilizes either magnetic resonance images or combined magnetic resonance and computed tomography images as a template for creating either the intervertebral scaffold or the joint repair scaffold (e.g., osteochondral scaffold) with fixation to the underlying bone. The disc scaffold design may include an outer annulus that may contain desired structures and a central nucleus pulposus region that could either contain a designed microstructure or a contained hydrogel. The osteochondral scaffold may include a bone compartment interface with a cartilage compartment. The bone compartment may interface with a cutout portion of the bone through fixation components. Different microstructure designs may be created for the bone and cartilage compartment to represent desired mechanical and mass transport properties. The scaffolds are designed with a microstructure that controls elastic and permeability property distribution within the scaffold.

Claims

1. A method for designing a tissue scaffold for generating tissue in a patient, the method comprising:

creating a first set of databases representing a plurality of porous microstructure designs for the scaffold in image based format;

creating a second database representing scaffold exterior geometry desired to replace the native tissue in the patient in image based format;

creating a third database representing scaffold external fixation structure; and

merging the first set of databases representing the desired microstructure designs with the second database and the third database into an image-based design of the scaffold.

2. The method of claim 1 further comprising:

converting the image-based design to a fabrication geometry.

3. The method of claim 1 wherein:

the scaffold external fixation structure is designed to comprise at least one projection extending away from the scaffold.

4. The method of claim 3 wherein:

the projection is a peg or a spike or a plate.

5. The method of claim 1 wherein:

the scaffold is designed for intervertebral disc repair, or articulating joint repair, or total joint replacement.

6. A method for designing an intervertebral disc scaffold, the method comprising:

creating a first set of databases representing a plurality of porous microstructure designs for the scaffold in image based format;

creating a second database representing scaffold exterior geometry desired to replace the native disc in the patient in image based format; and

merging the first set of databases representing the desired microstructure designs with the second database into an image-based design of the scaffold.

7. The method of claim 6 further comprising:

converting the image-based design to a fabrication geometry.

8. The method of claim 6 wherein:

the image-based design of the scaffold includes an outer annulus having a first designed porous microstructure, and

the image-based design of the scaffold includes a central region having a second designed microstructure.

9. The method of claim 6 wherein:

at least one of the microstructure designs is a wavy fiber design.

10. The method of claim 6 wherein:

the image-based design of the scaffold is designed to include spherical or elliptical pores.

11. A method for designing an osteochondral scaffold for replacing native tissue in a patient, the method comprising:

creating a first set of databases representing a plurality of porous microstructure designs for the scaffold in image based format;

creating a second database representing scaffold exterior geometry desired to replace the native tissue in the patient in image based format; and

merging the first set of databases representing the desired microstructure designs with the second database into an image-based design of the scaffold,

wherein the image-based design includes a bone region designed to have a first physical or biochemical property and a cartilage region designed to have a second physical or biochemical property.

12. The method of claim 11 wherein:

the first physical or biochemical property is a mechanical property, and

the second physical or biochemical property is a mechanical property.

13. The method of claim 11 wherein:

the first physical or biochemical property is a mass transport property, and

the second physical or biochemical property is a mass transport property.

14. The method of claim 11 wherein:

the first physical or biochemical property is a biochemical property, and

the second physical or biochemical property is a biochemical property.

15. The method of claim 11 wherein:

the first physical or biochemical property is achieved by coating at least a portion of the bone region with an osteoconductive mineral comprising a calcium compound.

16. A method for designing a joint replacement for a patient, the method comprising:

creating a first set of databases representing a plurality of porous microstructure designs for the joint replacement in image based format;

creating a second database representing joint replacement exterior geometry in image based format; and

merging the first set of databases representing the desired microstructure designs with the second database into an image-based design of the joint replacement,

wherein the image-based design includes a bone region designed to have a first physical or biochemical property and a surface region designed to have a second physical or biochemical property.

17. The method of claim 16 wherein:

the first physical or biochemical property is a mechanical property, and

the second physical or biochemical property is a mechanical property.

18. The method of claim 16 wherein:

the first physical or biochemical property is a mass transport property, and

the second physical or biochemical property is a mass transport property.

19. The method of claim 16 wherein:

the first physical or biochemical property is a biochemical property, and

the second physical or biochemical property is a biochemical property.

20. The method of claim 16 wherein:

the first physical or biochemical property is achieved by coating at least a portion of the bone region with an osteoconductive mineral comprising a calcium compound.

21. An intervertebral disc repair and/or regeneration scaffold comprising:

a central core shaped to approximate the nucleus pulposus of a natural intervertebral disc, the central core having a first porous microstructure; and

an outer annulus shaped to approximate the annulus fibrosus of a natural intervertebral disc, the outer annulus connected to and surrounding the central core, the outer annulus having a second porous microstructure,

wherein the central core and the outer annulus have different permeability.

22. The scaffold of claim 21 wherein:

the central core and the outer annulus have different elasticity.

23. The scaffold of claim 21 wherein:

the central core includes a bioactive agent.

24. The scaffold of claim 23 wherein:

the bioactive agent is selected from undifferentiated chondrocyte precursor cells from periosteum, mesenchymal stem cells from bone marrow, chondrocytes, sclerosing agents, angiogenesis activators, angiogenesis inhibitors, and mixtures thereof.

25. The scaffold of claim 21 wherein:

the scaffold is formed from a biodegradable polymer.