Stable Cartilage Defect Repair Plug

• US 20100286795A1
• Filed: 07/19/2010
• Published: 11/11/2010
• Est. Priority Date: 02/26/2007
• Status: Active Grant

• Current Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Biomet Sports Medicine LLC (Zimmer Biomet Holdings, Inc.)
• Inventors: Stone, Kevin T., Troxel, Karen
• Granted Patent: US 8,142,502 B2
• Time in Patent Office: Days
• US Class Current: 623/23.72
• 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 2/3859 Femoral components
• CPC Class Codes: A61F 2/4644 Preparation of bone graft, bone plugs or bone dowels, e.g. grinding or milling bone material bone material A61F2/28; disintegrating or milling devices B02C
• 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 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/2839 Bone plugs or bone graft dowels
• 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 2002/30011 differing in porosity
• CPC Class Codes: A61F 2002/30036 differing in release or diffusion time
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30113 circular
• CPC Class Codes: A61F 2002/30125 elliptical or oval
• CPC Class Codes: A61F 2002/30153 rectangular
• CPC Class Codes: A61F 2002/30156 triangular
• CPC Class Codes: A61F 2002/30179 X-shaped
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30233 Stepped cylinders, i.e. having discrete diameter changes
• CPC Class Codes: A61F 2002/30261 parallelepipedal
• CPC Class Codes: A61F 2002/3028 polyhedral different from parallelepipedal and pyramidal
• CPC Class Codes: A61F 2002/30327 : differing in diameter
• CPC Class Codes: A61F 2002/30332 : Conically- or frustoconically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30448 : using adhesives
• CPC Class Codes: A61F 2002/30459 : stapled
• CPC Class Codes: A61F 2002/30461 : sutured, ligatured or stitched
• CPC Class Codes: A61F 2002/30677 : Means for introducing or releasing pharmaceutical products, e.g. antibiotics, into the body
• CPC Class Codes: A61F 2002/30733 : Inserts placed into an endoprosthetic cavity, e.g. for modifying a material property
• CPC Class Codes: A61F 2002/30795 : Blind bores, e.g. of circular cross-section
• CPC Class Codes: A61F 2002/30971 : Laminates, i.e. layered products
• CPC Class Codes: A61F 2210/0004 : bioabsorbable
• CPC Class Codes: A61F 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2220/005 : using adhesives
• CPC Class Codes: A61F 2220/0066 : stapled
• CPC Class Codes: A61F 2220/0075 : sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/0006 : circular
• CPC Class Codes: A61F 2230/0008 : elliptical or oval
• CPC Class Codes: A61F 2230/0019 : rectangular
• CPC Class Codes: A61F 2230/0023 : triangular
• CPC Class Codes: A61F 2230/0058 : X-shaped
• CPC Class Codes: A61F 2230/0063 : Three-dimensional shapes
• 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 2250/0023 : differing in porosity
• CPC Class Codes: A61F 2250/0035 : differing in release or diffusion time
• CPC Class Codes: A61F 2250/0039 : differing in diameter
• CPC Class Codes: A61F 2310/00293 : containing a phosphorus-containing compound, e.g. apatite
• CPC Class Codes: A61F 2310/00341 : Coral, e.g. aragonite, porite
• CPC Class Codes: A61F 2310/00365 : Proteins; Polypeptides; Degradation products thereof

Abstract

An apparatus and method of distributing a load to a cartilage defect repair plug is provided. A load is applied to a first articulation layer. The load is distributed to a second layer and the load is transferred in the normal direction to the first density of subchondral bone. The load is distributed to a third layer and the load is transferred in the normal direction to a second density of subchondral bone. The load is then distributed to a fourth layer and the load is transferred in the normal direction to a third density of subchondral bone.

Claims

1. A cartilage defect repair plug that extends along a longitudinal axis for distributing a load at a cartilage defect site, comprising:

a first layer having a first width bound by a first wall defining a perimeter of the first layer, the first layer including a superior layer and an inferior layer each extending across the width of the first layer so as to form the perimeter of the first layer, the superior layer and inferior layer abutting each other in a stacked relationship along the longitudinal axis, the inferior layer defining a first shoulder having a first bearing surface perpendicular to the longitudinal axis, the first layer including a first thickness extending along the longitudinal axis that is configured to extend from a region of cartilage at the cartilage defect site to a region of underlying bone at the defect site; and

a second layer having a second width bound by a second wall defining a perimeter of the second layer, the second layer abutting the inferior layer of the first layer to form a stacked relationship along the longitudinal axis, the second width of the second layer being smaller than the first width of the first layer, the second layer defining a second shoulder having a second bearing surface perpendicular to the longitudinal axis, the second shoulder being spaced inward from the first shoulder in a direction towards the longitudinal axis.

2. The cartilage defect repair plug of claim 1, further comprising a third layer having a third width bound by a third wall defining a perimeter of the third layer, the third layer abutting the second layer to form a stacked relationship along the longitudinal axis, the third width of the third layer being smaller than the second width of the second layer, the third layer defining a third shoulder having a third bearing surface perpendicular to the longitudinal axis, the third shoulder being spaced inward from the second shoulder in a direction towards the longitudinal axis.

3. The cartilage defect repair plug of claim 1, wherein the inferior and superior layers of the first layer are each formed of different materials.

4. The cartilage defect repair plug of claim 3, wherein at least the superior layer of the first layer is formed from a synthetic resorbable material.

5. The cartilage defect repair plug of claim 1, wherein at least the one of the first and second layers includes an attachment feature associated with the respective first and second walls.

6. The cartilage defect repair plug of claim 2, wherein the first, second and third walls each include a cylindrical and smooth outer periphery.

7. The cartilage defect repair plug of claim 2, wherein the first, second and third layers are secured to each other using at least one of a mechanical attachment, an adhesive attachment, a chemical attachment, or combinations thereof.

8. The cartilage defect repair plug of claim 2, further comprising a bore formed through the first and second layers and partially into the third layer, the bore being centered about the longitudinal axis.

9. The cartilage defect repair plug of claim 8, further comprising a bioactive material deposited into the bore so as to have a top surface co-planar with a top surface of the superior layer of the first layer, the bioactive material being selected from the group consisting of:

chondrocytes, undifferentiated cells, differentiation media, growth factors, platelet concentrate, nutrients, bone morphogenic proteins, osteogenic factors, and combinations thereof.

10. The cartilage defect repair plug of claim 2, further comprising the first layer having a thickness greater than each of the second and third layers.

11. The cartilage defect repair plug of claim 2, further comprising the first, second and third layers each being formed of a different material.

12. The cartilage defect repair plug of claim 2, wherein the perimeters of the first, second and third walls are parallel to the longitudinal axis.

13. The cartilage defect repair plug of claim 2, wherein the perimeters of the first, second and third walls are tapered relative to the longitudinal axis.

14. The cartilage defect repair plug of claim 2, wherein the first, second and third walls define one of a circular, oval, polygonal or cruciform shape.

15. The cartilage defect repair plug of claim 1, wherein the superior layer includes a thickness configured to engage the region of cartilage and the inferior layer includes a thickness configured to engage the region of underlying bone.

16. A cartilage defect repair plug that extends along a longitudinal axis for distributing a load at a cartilage defect site, comprising:

first, second and third layers each having respective first, second and third diameters, where the second diameter is smaller than the first diameter and larger than the third diameter, each layer being bound by a wall defining a perimeter of the respective layer, the wall of each layer being parallel to the longitudinal axis, each of the first, second and third layers defining a shoulder having a bearing surface perpendicular to the longitudinal axis, the first, second and third layers being positioned relative to each other in a stacked relationship extending along the longitudinal axis to form a stepped cone geometry, the bearing surface of each respective layer being orthogonal to the respective wall of each layer;

wherein the first layer is formed of a different material than at least one of the second and third layers.

17. The cartilage defect repair plug of claim 16, wherein the first layer is formed of a synthetic resorbable material and the second and third layers are formed of a natural material.

18. The cartilage defect repair plug of claim 16, further comprising a bioactive agent absorbed into at least the first layer.

19. The cartilage defect repair plug of claim 16, wherein the first layer includes an upper portion and a lower portion each extending across the entire diameter of the first layer and being formed of different materials, the first layer having a thickness extending along the longitudinal axis greater than a thickness of the second and third layers.

20. The cartilage defect repair plug of claim 19, wherein the second and third layers are formed from a monolithic piece of material.

21. The cartilage defect repair plug of claim 16, further comprising a closed-end bore formed through the first layer and into at least a portion of the second layer, the bore being centered around the longitudinal axis and having a conical configuration with a greater diameter at an open end of the bore adjacent a top surface of the first layer.

22. The cartilage defect repair plug of claim 21, further comprising a bioactive material deposited into the bore so as to have a top surface co-planar with a top surface of the first layer.

23. The cartilage defect repair plug of claim 16, wherein each layer includes a smooth outer periphery.

24. The cartilage defect repair plug of claim 16, wherein the first layer includes a smooth outer periphery and the second and third layers include an attachment feature associated with an outer periphery of each layer, the attachment feature including at least one of a spike, a ridge, a thread, or combinations thereof.

25. A cartilage defect repair plug that extends along a longitudinal axis for distributing a load at a cartilage defect site, comprising:

a first layer having a first diameter bound by a first wall parallel to the longitudinal axis and defining a perimeter of the first layer, the first layer including a superior layer and an inferior layer each extending across the diameter of the first layer so as to form the perimeter of the first layer, the superior layer and inferior layer being formed of different materials and abutting each other in a stacked relationship along the longitudinal axis, the inferior layer defining a first shoulder having a first bearing surface perpendicular to the longitudinal axis, the first layer including a first thickness extending along the longitudinal axis that is configured to extend from a region of cartilage at the cartilage defect site to a region of underlying bone at the defect site;

second and third layers each having respective second and third diameters and being bound by respective second and third walls parallel to the longitudinal axis, the second and third walls each defining a perimeter of the respective second and third layers, the second layer having a diameter smaller than the first layer and greater than the second layer, the second layer abutting the inferior layer and the third layer abutting the second layer to form a stepped cone stacked geometry extending along the longitudinal axis;

a closed-end bore formed through the first layer and at least partially into the second layer, the closed-end bore being formed about the longitudinal axis; and

a bioactive material deposited into the bore so as to have a top surface co-planar with a top surface of the superior layer;

wherein the first layer includes a thickness greater than at least a thickness of the second or third layers.

26. The cartilage defect repair plug of claim 25, wherein the superior layer includes a thickness configured to engage the region of cartilage and the inferior layer includes a thickness configured to engage the region of underlying bone.