Anchored multi-phasic osteochondral construct

• US 8,475,531 B1
• Filed: 04/20/2010
• Issued: 07/02/2013
• Est. Priority Date: 04/21/2009
• Status: Active Grant

• Current Assignee: Clemson University
• Original Assignee: Clemson University
• Inventors: Burg, Karen J. L., Maxson, Scott A.
• Primary Examiner(s): Sweet, Thomas J
• Assistant Examiner(s): DUKERT, BRIAN AINSLEY
• Application Number:
  US12/763,515
• Time in Patent Office: 1,169 Days
• Field of Search: 623/23.51, 623/23.56
• US Class Current: 623/14.12
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/30756 Cartilage endoprostheses A61F2/3603 takes precedence
• CPC Class Codes: A61F 2002/30772 Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/30878 with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
• CPC Class Codes: A61L 2430/24 for joint reconstruction
• CPC Class Codes: A61L 27/18 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/20 Polysaccharides
• CPC Class Codes: A61L 27/3834 Cells able to produce different cell types, e.g. hematopoietic stem cells, mesenchymal stem cells, marrow stromal cells, embryonic stem cells
• CPC Class Codes: A61L 27/46 with phosphorus-containing inorganic fillers
• CPC Class Codes: A61L 27/52 Hydrogels or hydrocolloids
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: C08L 5/12 Agar or agar-agar , i.e. mixture of agarose and agaropectin; Derivatives thereof
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence
• CPC Class Codes: C08L 75/04 Polyurethanes

Abstract

Disclosed are osteochondral constructs that can be utilized to encourage both bone and articular cartilage tissue repair in synovial joints. Disclosed constructs are composites including a hydrogel portion for implant in a cartilage defect site and an adjacent portion for implant in a bone defect site. The portion to be implanted in a bone defect site can include a polymeric/ceramic composite material. Disclosed constructs also include a polymeric anchor that can secure the construct at the desired site. Disclosed constructs can also include capillary channeled fibers within the bone portion of the construct that can provide improved nutrient flow to and waste flow from cells growing and developing on and in the construct.

Claims

1. An osteochondral construct comprising:

a cartilage portion, the cartilage portion including a hydrogel comprising a polymeric matrix;

a bone portion comprising at least one capillary channeled fiber, the capillary channeled fiber having a non-circular cross section and including a plurality of co-linear channels extending the entire length of the exterior surface of the capillary channeled fiber, the capillary channeled fiber defining a fluid conduit within the bone portion, the bone portion being adjacent to the cartilage portion; and

a polymeric anchor adjacent to at least one of the bone portion and the cartilage portion, the polymeric anchor providing a pressure fit between the osteochondral construct and a surrounding structure.

2. The osteochondral construct of claim 1, the bone portion further comprising a polymer/ceramic composite material including a biocompatible polymer and a calcium phosphate ceramic.

3. The osteochondral construct of claim 2, wherein the calcium phosphate ceramic comprises at least one of hydroxyapatite and tricalcium phosphate.

4. The osteochondral construct of claim 2, the polymer/ceramic composite material comprising a polylactide copolymer.

5. The osteochondral construct of claim 1, the bone portion comprising multiple capillary channeled fibers, the bone portion defining a fluid conduit between adjacent capillary channeled fibers.

6. The osteochondral construct of claim 1, the bone portion being between the cartilage portion and the polymeric anchor.

7. The osteochondral construct of claim 1, wherein the polymeric anchor encircles a portion of the cartilage portion or the bone portion.

8. The osteochondral construct of claim 1, the bone portion comprising a bundle of capillary channeled fibers.

9. The osteochondral construct of claim 1, the bone portion comprising a plurality of bundles of capillary channeled fibers.

10. The osteochondral construct of claim 1, the polymeric matrix of the hydrogel comprising a hydrolyzable portion.

11. The osteochondral construct of claim 1, at least one of the cartilage portion and the bone portion comprising a cell.

12. The osteochondral construct of claim 11, wherein the cartilage portion comprises a cell and the cell is a chondrocyte or an undifferentiated mesenchymal stem cell.

13. The osteochondral construct of claim 11, wherein the bone portion comprises a cell and the cell is an osteoblast or an osteocyte.

14. The osteochondral construct of claim 1, wherein at least one of the bone portion, the cartilage portion, and the polymeric anchor further comprises a bioactive agent.

15. The osteochondral construct of claim 1, wherein the polymeric anchor comprises a polymer having a glass transition temperature of less than about 37°

C.