Composite orthopedic prosthesis and method for making same
Patent Information
- Application Number
- JP2022527136
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2020-08-27
- Filing Date
- 2020-11-11
- Publication Date
- 2025-03-04
- Estimated Expiration
- 2040-11-11
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Abstract
Description
[Technical field]
[0001] This application claims priority to U.S. Provisional Application No. 62 / 934,278 (filed November 12, 2019), and U.S. Provisional Application No. 63 / 070,963 (filed August 27, 2020), the disclosures of each of which are incorporated by reference in their entireties.
[0002] FIELD OF THEINVENTION The present disclosure relates generally to orthopedic prostheses, and more particularly to composite orthopedic prostheses. [Background technology]
[0003] Arthroplasty is a well-known surgical procedure in which a diseased and / or damaged natural joint is replaced with an artificial joint. A typical knee prosthesis includes a patella prosthetic component, a tibial tray, a femoral component, and a bearing component positioned between the tibial tray and the femoral component. The femoral component is designed to be attached to a surgically-prepared distal end of the patient's femur. The tibial tray is designed to be attached to a surgically-prepared proximal end of the patient's tibia.
[0004] The femoral and tibial components are typically made from a biocompatible material, such as a metal alloy of cobalt chromium or titanium, and the bearing component disposed between them is typically formed from a plastic material, such as polyethylene. Summary of the Invention [Means for solving the problem]
[0005] The orthopaedic implant comprises a femoral component configured to be coupled to a distal end of a patient's femur, the femoral component including: (i) an articular layer curved in a sagittal plane and including an articular surface configured to engage the tibial component, and (ii) a support layer positioned opposite the articular surface and including a bone-facing surface configured to engage the distal end of the patient's femur. In some embodiments, the implant comprises a tibial component configured to be coupled to a proximal end of a patient's tibia, the tibial component including a concave surface shaped to engage the articular surface of the femoral component.
[0006] In some embodiments, the articular layer of the femoral component is constructed of a material comprising a homopolymer or copolymer, or a composite material comprising a blend of polymers.
[0007] In some embodiments, the support layer is comprised of a composite material including (i) a homopolymer, copolymer, or mixtures thereof, and (ii) reinforcing fibers.
[0008] Further embodiments, features, and advantages of the present disclosure will become apparent from the following Detailed Description and by practice of the disclosure. The compositions and materials of the present disclosure can be described as embodiments described in any one of the sections listed below. It will be understood that any of the embodiments described herein can be used in conjunction with any other embodiment described herein, unless the embodiments are mutually inconsistent.
[0009] 1. An orthopedic knee prosthesis system comprising: a tibial component configured to be implanted into a proximal end of a patient's tibia, the tibial component including a concave bearing surface; a femoral component configured to be implanted into a distal end of a patient's femur, the femoral component including: (i) an articular layer including an articular surface curved in a sagittal plane and configured to articulate with a concave bearing surface of the tibial component; and (ii) a support layer positioned opposite the articular surface and including a bone-facing surface configured to engage the distal end of the patient's femur; the articular layer of the femoral component comprises a polyetheretherketone (PEEK) homopolymer; An orthopaedic knee prosthesis system, wherein the support layer comprises: (i) reinforcing fibers; and (ii) a homopolymer, a copolymer, or a mixture thereof.
[0010] 2. The orthopedic prosthetic system of claim 1, wherein the articular layer further comprises a polysulfone, a polyimide, or a mixture thereof.
[0011] 3. The orthopedic prosthesis system according to item 1 or 2, wherein PEEK constitutes about 75% to about 95% by weight of the articular layer.
[0012] 4. The orthopedic prosthesis system according to any one of items 1 to 3, wherein the support layer comprises a polycyclic aromatic ether homopolymer.
[0013] 5. The orthopedic prosthesis system according to any one of claims 1 to 3, wherein the support layer comprises a polyacetal copolymer.
[0014] 6. The orthopedic prosthesis system of claim 5, wherein the polyacetal copolymer is a polyoxymethylene copolymer.
[0015] 7. The orthopedic prosthesis system of any one of paragraphs 1-3, 5, or 6, wherein the support layer comprises at least about 80% polyoxymethylene.
[0016] 8. The orthopedic prosthesis system according to any one of items 1 to 7, wherein the reinforcing fiber is glass fiber or carbon fiber.
[0017] 9. An orthopedic knee prosthesis comprising: a femoral component including: (i) an articular layer including an articular surface curved in a sagittal plane and configured to engage the tibial component; and (ii) a support layer including a femoral condyle positioned opposite the articular surface and including a bone-facing surface configured to engage a distal end of a patient's femur; the articular layer is comprised of a composite material including a blend of polyetheretherketone (PEEK) homopolymer with polysulfone, polyimide, or a mixture thereof; An orthopaedic knee prosthesis, wherein the articular layer has a yield strength of at least about 100 MPa.
[0018] 10. The orthopedic knee prosthesis of paragraph 9, wherein the articular layer is substantially free of fibers.
[0019] 11. The orthopedic knee prosthesis of claim 9 or 10, wherein the articular layer has a tensile modulus of at least about 4,000 MPa.
[0020] 12. The joint layer must be at least 5 J / m 2 Item 12. The orthopedic knee prosthesis according to any one of items 9 to 11, having an IZOD toughness of 1.
[0021] 13. The orthopedic knee prosthesis according to any one of paragraphs 9 to 12, wherein PEEK is about 75% to about 95% by weight of the articular layer.
[0022] 14. An orthopedic knee prosthesis comprising: a femoral component including: (i) an articular layer including an articular surface curved in a sagittal plane and configured to engage the tibial component; and (ii) a support layer including a femoral condyle positioned opposite the articular surface and including a bone-facing surface configured to engage a distal end of a patient's femur; The support layer comprises: (i) a homopolymer, a copolymer, or a mixture thereof; and (ii) reinforcing fibers; An orthopedic knee prosthesis, wherein the support layer has a tensile modulus of about 3,000 MPa to about 30,000 MPa.
[0023] 15. The orthopedic knee prosthesis of claim 14, wherein the support layer comprises a polyoxymethylene copolymer.
[0024] 16. The orthopedic knee prosthesis of paragraph 14, wherein the support layer comprises a polycyclic aromatic ether.
[0025] 17. An orthopedic knee prosthesis comprising: a femoral component including: (i) an articular layer including an articular surface curved in a sagittal plane and configured to engage the tibial component; and (ii) a support layer including a femoral condyle positioned opposite the articular surface and including a bone-facing surface configured to engage a distal end of a patient's femur; the articular layer of the femoral component comprises a homopolymer; The orthopaedic knee prosthesis, wherein the support layer comprises a copolymer and a reinforcing fiber.
[0026] 18. The orthopedic knee prosthesis of claim 17, wherein the homopolymer of the articular layer is a polycyclic aromatic ether or a polyacetal.
[0027] 19. The orthopedic knee prosthesis of claim 17 or 18, wherein the articular layer comprises a polyacetal copolymer.
[0028] 20. The orthopedic knee prosthesis according to claim 19, wherein the polyacetal copolymer is a polyoxymethylene copolymer.
[0029] 21. The orthopedic knee prosthesis of claim 20, wherein the articular layer comprises at least about 80% polyoxymethylene copolymer.
[0030] 22. The orthopedic knee prosthesis according to claim 18, wherein the polycyclic aromatic ether is polyetheretherketone (PEEK).
[0031] 23. The orthopedic knee prosthesis according to item 22, wherein PEEK is about 75% to about 95% by weight of the articular layer.
[0032] 24. A method of making an implantable component for an orthopedic prosthesis, comprising: molding a first layer of polymeric material to a second layer of polymeric material to form a composite material; forming the composite material into a predetermined shape of an implantable component, the implantable component having an articular layer and a support layer; The method, wherein the articular layer comprises a homopolymer and the support layer comprises a polymer and reinforcing fibers.
[0033] 25. The method of claim 24, wherein forming the implantable component is an acetabular bearing adapted to be implanted in the patient's acetabulum.
[0034] 26. The method of claim 24, wherein the implantable component is a glenoid bearing adapted to be implanted in the patient's glenoid cavity.
[0035] 27. The method of claim 24, wherein the implantable component is a tibial bearing adapted to be implanted in the patient's tibia.
[0036] 28. The method of any one of claims 24 to 27, wherein the articular layer comprises a polyetheretherketone (PEEK) homopolymer.
[0037] 29. The method of claim 28, wherein the articular layer further comprises polysulfone, polyimide, or a mixture thereof.
[0038] 30. The method according to item 28 or 29, wherein PEEK is about 75% to about 95% by weight of the articular layer.
[0039] 31. A method of making a femoral component of a knee prosthesis, comprising: molding a first layer of polymeric material to a second layer of polymeric material to form a composite material; forming the composite material into a predetermined shape of a femoral component, the femoral component having an articular layer and a bearing layer; The method, wherein the articular layer comprises a homopolymer and the support layer comprises a polymer and reinforcing fibers.
[0040] 32. A method of forming a femoral component of a knee prosthesis, comprising: Molding the articular layer and the support layer together to form a composite material; forming the composite material into a predetermined shape of the femoral component; The method, wherein the articular layer is comprised of a first polymeric material comprising a blend of homopolymers, and the support layer comprises a second polymeric material different from the first polymeric material and comprising reinforcing fibers.
[0041] 33. The method of claim 32, wherein the first polymeric material comprises a polysulfone, a polyimide, or a mixture thereof.
[0042] 34. The method according to item 32 or 33, wherein the homopolymer of the articular layer is a polycyclic aromatic ether or a polyacetal.
[0043] 35. The method according to claim 34, wherein the polycyclic aromatic ether is polyether ether ketone (PEEK).
[0044] 36. The method of any one of paragraphs 32 to 35, wherein the support layer comprises a copolymer and a reinforcing fiber.
[0045] 37. The method of claim 36, wherein the copolymer of the support layer is a polyacetal.
[0046] 38. The method according to item 37, wherein the polyacetal is polyoxymethylene.
[0047] 39. A method of forming a first component for an orthopaedic implant, comprising: co-molding a composite of a first polymeric material comprising a polycyclic aromatic ether and a second polymeric material comprising a polymer and reinforcing fibers; forming the composite material into a predetermined shape of the first component; A method, wherein a first polymeric material is configured to engage a second component of an orthopedic implant and a second polymeric material is configured to engage bone.
[0048] 40. The method of claim 39, wherein the first polymeric material comprises a homopolymer, a copolymer, or a mixture thereof.
[0049] 41. The method of claim 40, wherein the homopolymer of the first polymeric material is a polycyclic aromatic ether.
[0050] 42. The method of any one of paragraphs 39 to 41, wherein the first polymeric material further comprises a polysulfone, a polyimide, or a mixture thereof.
[0051] 43. The method according to any one of items 39 to 42, wherein the polycyclic aromatic ether is polyether ether ketone (PEEK).
[0052] 44. The method of any one of paragraphs 39 to 43, wherein the polymer of the second polymeric material comprises a copolymer.
[0053] 45. The method of claim 44, wherein the copolymer of the second polymeric material is polyacetal.
[0054] 46. The method according to item 45, wherein the polyacetal is polyoxymethylene.
[0055] 47. The method of any one of paragraphs 39 to 46, wherein forming the composite material includes molding the composite material into an acetabular bearing adapted to be implanted in the patient's acetabulum.
[0056] 48. The method of any one of paragraphs 39 to 46, wherein forming the composite material includes molding the composite material into a glenoid bearing adapted to be implanted in the patient's glenoid cavity.
[0057] 49. The method of any one of paragraphs 39 to 46, wherein forming the composite material includes molding the composite material into a tibial bearing adapted to be implanted in the patient's tibia.
[0058] 50. An orthopedic knee prosthesis comprising: a femoral component including a femoral condyle having an articular surface curved in a sagittal plane and configured to engage the tibial component, and a bone-facing surface positioned opposite the articular surface and configured to engage a distal end of the patient's femur; the femoral component comprises at least about 50% by weight of a homopolymer or a blend of a homopolymer with a polysulfone, a polyimide, or a mixture thereof; An orthopaedic knee prosthesis, wherein the femoral component has a yield strength of at least about 100 MPa.
[0059] 51. The orthopedic knee prosthesis according to paragraph 50, wherein the homopolymer is a polycyclic aromatic ether or a polyacetal.
[0060] 52. The orthopedic knee prosthesis according to claim 51, wherein the polycyclic aromatic ether is polyetheretherketone (PEEK).
[0061] 53. The orthopedic knee prosthesis of claim 52, wherein PEEK is about 75% to about 95% by weight of the femoral component.
[0062] 54. The orthopedic knee prosthesis according to paragraph 51, wherein the polyacetal is polyoxymethylene.
[0063] 55. An orthopedic prosthesis, comprising: a first component including an articular layer and a support layer, the articular layer configured to engage a second component of the prosthesis and the support layer configured to engage a bone of the patient; An orthopedic prosthesis, wherein the articular layer is comprised of a blend of a polyaryletherketone and a second polymer, and the support layer is comprised of a polymeric material.
[0064] 56. The orthopedic prosthesis according to paragraph 55, wherein the second polymer of the articular layer is a polysulfone or a polyimide.
[0065] 57. The orthopedic prosthesis according to paragraph 56, wherein the polysulfone is PPSU.
[0066] 58. The orthopedic prosthesis according to paragraph 56, wherein the polyimide is PEI.
[0067] 59. An orthopedic prosthesis according to any one of paragraphs 55 to 58, wherein the polyaryletherketone is at least about 80% by weight, preferably at least about 85% by weight.
[0068] 60. The orthopedic prosthesis of any one of paragraphs 55-59, wherein the second polymer is present in an amount of less than about 20% by weight, preferably less than about 15% by weight.
[0069] 61. The orthopedic prosthesis of any one of paragraphs 55 to 60, wherein the second polymer is present at about 5% to about 20% by weight.
[0070] 62. The orthopedic prosthesis according to any one of claims 55 to 61, wherein the support layer comprises reinforcing fibers or reinforcing particles.
[0071] 63. The orthopedic prosthesis according to any one of paragraphs 55 to 62, wherein the support layer comprises reinforcing fibers, preferably glass fibers or carbon fibers.
[0072] 64. The orthopedic prosthesis according to any one of paragraphs 55 to 62, wherein the support layer comprises reinforcing particles, preferably barium sulfate.
[0073] 65. The orthopedic prosthesis according to any one of paragraphs 55 to 62, wherein the support layer does not contain reinforcing fibers or reinforcing particles.
[0074] 66. An orthopedic prosthesis according to any one of paragraphs 55 to 65, wherein the articular layer does not contain reinforcing fibers or reinforcing particles.
[0075] 67. An orthopedic prosthesis according to any one of paragraphs 55 to 66, wherein the articular layer has a yield strength of at least about 100 MPa, preferably at least about 102 MPa.
[0076] 68. An orthopedic prosthesis according to any one of paragraphs 55 to 67, wherein the articular layer has a tensile modulus of at least 3,000 MPa, preferably at least 4,000 MPa.
[0077] 69. The orthopedic prosthesis of any one of paragraphs 55 to 68, wherein the articular layer has a compressive yield of at least about 100 MPa, preferably at least about 105 MPa, or more preferably at least about 110 MPa.
[0078] 70. The joint layer should be at least 5 J / m 2 or about 5.3 J / m 2 ~about 8J / m 2 Item 70. The orthopedic knee prosthesis according to any one of items 55 to 69, having an IZOD toughness of 100% or more.
[0079] 71. The orthopedic knee prosthesis of any one of paragraphs 55 to 70, wherein the wear rate of the articular layer is less than about 10, preferably less than about 6, or preferably less than about 4 mg / million cycles (MC).
[0080] 72. An orthopedic knee prosthesis according to any one of paragraphs 55 to 71, wherein the first component is an acetabular component adapted to be implanted in the patient's acetabulum.
[0081] 73. The orthopedic knee prosthesis of any one of paragraphs 55 to 71, wherein the first component is a glenoid component adapted to be implanted in a glenoid cavity of a patient.
[0082] 74. The orthopaedic knee prosthesis of any one of paragraphs 55 to 71, wherein the first component is a tibial component adapted to be implanted into the patient's tibia.
[0083] 75. The orthopedic knee prosthesis of any one of paragraphs 55 to 71, wherein the first component is a femoral component adapted to be implanted into the patient's femur. [Brief description of the drawings]
[0084] The detailed description makes specific reference to the following drawings: [Figure 1] FIG. 1 is an exploded perspective view of an orthopaedic knee prosthesis. [Diagram 2] 2 is a cross-sectional view of the femoral component and tibial bearing of FIG. 1 generally taken along line 2-2 of FIG. 1 as viewed in the direction of the arrows. [Diagram 3] 1 is a graph showing the tensile strength of various compositions disclosed herein. [Figure 4] 1 is a graph showing the tensile modulus of various compositions disclosed herein. [Diagram 5] 1 is a graph showing the compressive strength of various compositions disclosed herein. [Figure 6] 1 is a graph showing the IZOD impact toughness of various compositions disclosed herein. [Figure 7] 1 is a graph showing the average wear rates of the pin and the disk after phase 1 ("as is") and phase 2 ("scratched"). [Figure 8] 1 is a graph showing the average roughness Sa (μm) of coupons containing different polymers in each interval of phase 1 (0.0-1.98 million cycles (MC)) and phase 2 (2.31-4.29 MC). [Figure 9] 1 is a graph showing the average cumulative pin wear per spacing for pins containing POM, PEEK, PEEK / 20% PEI, or PEEK / 10% PPSU. [Figure 10] 1 is a graph showing cumulative disk wear per interval for disks containing POM, PEEK, PEEK / 20% PEI, or PEEK / 10% PPSU. [Figure 11] 1 is a graph showing the counter surface roughness of various disks including POM, PEEK, PEEK / 20% PEI, or PEEK / 10% PPSU. [Figure 12] 1 is a graph showing the average cumulative pin wear per interval when the pin interacts with a disk containing POM, PEEK, PEEK / 20% PEI, or PEEK / 10% PPSU. [Figure 13] 1 is a graph showing the average cumulative disk wear per interval as each disk interacts with the pin. [Figure 14] 1 is a graph showing composite pin and disc wear rates. [Figure 15] 10 is a graph showing the facing surface roughness of the disk using an interferometer after subsequent cycle counts. [Figure 16] 1 is a graph showing fatigue testing of disks containing PEEK, PEEK / 10% PEI, or PEEK / 10% PPSU. [Figure 17] FIG. 2 is a perspective view of the glenoid component of a shoulder prosthesis. [Figure 18] 18 is a cross-sectional view taken along line 18-18 in FIG. 17, as viewed in the direction of the arrows. [Figure 19] FIG. 2 is a perspective view of the acetabular component of a hip joint prosthesis. [Figure 20] 20 is a cross-sectional view taken along line 20-20 of FIG. 19, as viewed in the direction of the arrows. [Figure 21]2 is a perspective view of another embodiment of the tibial component of FIG. 1. [Figure 22] 22 is a cross-sectional view taken along line 22-22 of FIG. 21, as viewed in the direction of the arrows. [Diagram 23] FIG. 1 is a perspective view of the head component of a hip or shoulder prosthesis; [Figure 24] 24 is a cross-sectional view taken along line 24-24 in FIG. 23, as viewed in the direction of the arrows. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0085] While the concepts of the present disclosure are susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that it is not the intention of this disclosure to limit the concepts of the present disclosure to the particular forms disclosed, but rather, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure and the appended claims.
[0086] Terms denoting anatomical references, such as anterior, posterior, medial, lateral, superior, inferior, etc., may be used throughout this specification with respect to the orthopedic implants or prostheses and surgical instruments described herein, as well as with reference to the patient's natural anatomy. Such terms have well-understood meanings both in the study of anatomy and in the field of orthopedic surgery. Use of such anatomical reference terms in the written description and claims is intended to be consistent with their well-understood meanings, unless otherwise specified.
[0087] 1, in one embodiment, an orthopaedic knee prosthesis 10 includes a femoral component 12, a tibial bearing 14, and a tibial tray 16. The femoral component 12 is configured to articulate with the tibial bearing 14, which is configured to couple with the tibial tray 16. In the exemplary embodiment of FIG. 1, the tibial bearing 14 is embodied as a rotating or mobile tibial bearing, such that the tibial bearing 12 is configured to rotate relative to the tibial tray 16 during use. However, in other embodiments, the tibial bearing 14 may be embodied as a fixed tibial bearing, whose rotation relative to the tibial tray 16 may be limited or inhibited.
[0088] The tibial tray 16 is configured to be secured to a proximal end of a patient's tibia (not shown) that has been surgically prepared. The tibial tray 16 may be secured to the patient's tibia using bone adhesive or other attachment methods. The tibial tray 16 includes a platform 18 having an upper surface 20 and a bottom surface 22. Illustratively, the upper surface 20 is generally planar. The tibial tray 16 also includes a stem 24 that extends downwardly from the bottom surface 22 of the platform 18. A cavity or bore 26 is defined in the upper surface 20 of the platform 18 and extends downwardly into the stem 24. The bore 26 is formed to receive a complementary stem of the tibial insert 14, as will be described in further detail below.
[0089] As discussed above, the tibial bearing 14 is configured to be coupled to the tibial tray 16. The tibial bearing 14 includes a platform 30 having an upper bearing surface 32 and a lower surface 34. In an exemplary embodiment in which the tibial bearing 14 is embodied as a rotating or mobile tibial bearing, the bearing 14 includes a stem 36 extending downwardly from the lower surface 32 of the platform 30. When the tibial bearing 14 is coupled to the tibial tray 16, the stem 36 is received within the bore 26 of the tibial tray 16. During use, the tibial bearing 14 is configured to rotate relative to the tibial tray 16 about an axis defined by the stem 36. In an embodiment in which the tibial bearing 14 is embodied as a fixed tibial bearing, the tibial bearing 14 may or may not include a stem 22 and / or may include other devices or features for securing the tibial bearing 14 to the tibial tray 16 in a non-rotating configuration.
[0090] The upper bearing surface 32 of the tibial bearing 14 includes a medial bearing surface 42 and a lateral bearing surface 44. The medial bearing surface 42 and the lateral bearing surface 44 are configured to receive or otherwise contact the medial and lateral condyles of the corresponding femoral component 12, as described in further detail below. Accordingly, each of the bearing surfaces 42, 44 has a concave contour.
[0091] The femoral component 12 is configured to be coupled to a surgically prepared surface of the distal end of the patient's femur (not shown). The femoral component 12 may be secured to the patient's femur through the use of bone bonding or other attachment methods. The femoral component 12 includes an outer articular surface 50 having a pair of medial and lateral condyles 52, 54. The condyles 52, 54 are spaced apart to define an intercondylar opening 56 therebetween. In use, the condyles 52, 54 replace the natural condyles of the patient's femur and are configured to articulate on corresponding bearing surfaces 42, 44 of the platform 30 of the tibial bearing 14.
[0092] 1 is embodied as a posterior cruciate ligament-retaining knee prosthesis, i.e., the femoral component 12 is embodied as a posterior cruciate ligament-retaining knee prosthesis and the tibial bearing 14 is embodied as a posterior cruciate ligament-retaining tibial bearing 14. However, in other embodiments, the orthopaedic knee prosthesis 10 may be embodied as a posterior cruciate ligament-sacrificing knee prosthesis.
[0093] 2, the femoral component 12 is configured to articulate on the tibial bearing 14 during use. Each condyle 52, 54 of the femoral component 12 includes a condylar surface that is convexly curved in the sagittal plane and configured to contact a respective bearing surface 42, 44.
[0094] The femoral component 12 includes an articular layer 58 and a support layer 60, as shown in FIG. 2. The articular layer 58 is configured to form all or a portion of the articular surface 50. The support layer 60 is configured to form all or a portion of the bone-facing surface 62. The support layer 60 is configured to be coupled to a surgically-prepared surface of the distal end of a patient's femur (not shown). The articular layer 58 is secured to the support layer 60.
[0095] A polymer or blend of polymers is preferably used to construct layers 58, 60. As used herein, the term "polymer" is intended to mean any polymeric material that may be implanted in a patient. Specific examples of such polymers are polyaryletherketones (PAEKs), polysulfones, polyimides, and polyacetals. The term "polyaryletherketone" as defined herein includes polyetherketone (PEEK), polyetherketone, and polyetherketoneetherketoneketone, or any other type of polyaryletherketone used in the construction of prosthetic implants. The term "polymer" is also intended to include both homopolymers and copolymers.
[0096] It should be understood that the term "layer" as used herein is not intended to be limited to a "thickness" of material positioned proximate to another similarly dimensional "thickness" of material, but rather is intended to include numerous structures, configurations, and constructions of material. For example, the term "layer" may include a portion, region, or other structure of material positioned proximate to another portion, region, or structure of a different material. For example, an articular surface may define a first "layer" of material, while a support layer in contact with the articular layer may define a second "layer" of material.
[0097] In an exemplary embodiment, the articular layer 58 and the support layer 60 are molded together. In an exemplary embodiment, the articular layer 58 and the support layer 60 are combined to have a thickness of about 3 mm to about 8 mm. In an exemplary embodiment, the articular layer 58 and the support layer 60 are combined to have a thickness of about 5 mm. In an exemplary embodiment, the articular layer 58 has a thickness that is about 0.1 mm to 2 mm thick.
[0098] In exemplary embodiments, the articular layer 58, the support layer 60, or both the articular layer 58 and the support layer 60 are comprised of a polymeric material. In some embodiments, the articular layer 58 comprises a homopolymer, a copolymer, or a mixture thereof. In some embodiments, the articular layer 58 comprises two or more homopolymers. In some embodiments, the articular layer 58 consists of, or consists essentially of, homopolymers. In some embodiments, the articular layer 58 consists of, or consists essentially of, homopolymers and copolymers.
[0099] In some embodiments, the articular layer 58 is comprised of a composite material including a first polymer and a second polymer. In some embodiments, the first polymer is a homopolymer. In some embodiments, the second polymer is a homopolymer. In some embodiments, the articular layer 58 consists of, or consists essentially of, the first homopolymer and the second homopolymer. In an exemplary embodiment, the articular layer 58 does not include barium sulfate.
[0100] In some embodiments, the homopolymer of the articular layer 58 is a polyaromatic ether, a polyacetal, or a mixture thereof. An exemplary polyaromatic ether includes polyetheretherketone (or more commonly referred to as "PEEK"). In some examples, the articular layer 58 includes KETASPIRE KT-880 available from SOLVAY SPECIALTY POLYMERS. In some embodiments, the polyacetal is a polyoxymethylene (or more commonly referred to as "POM"). An exemplary polyoxymethylene homopolymer includes KEP H100 available from KEP Americas. In some embodiments, the polyacetal or polyaromatic ether is the first homopolymer.
[0101] In some embodiments, the articular layer 58 comprises a homopolymer present in a particular weight percentage. In exemplary embodiments, the articular layer 58 comprises at least about 50%, at least about 60%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, or at least about 95% by weight of a first homopolymer. In some embodiments, the homopolymer is about 100% by weight of the articular layer 58. In exemplary embodiments, the homopolymer is POM. In exemplary embodiments, the homopolymer is PEEK.
[0102] In some embodiments, the homopolymer of the articular layer 58 is a polyimide or polysulfone. In some embodiments, the polyimide can be a polyetherimide (commonly referred to as "PEI"). Exemplary PEIs include Ultem HU1000 from Sabic and COLORRX PEI-1600RX available from LTL COLOR COMPOUNDERS, LLC. In some embodiments, the polysulfone can be a polyphenylsulfone (commonly referred to as "PPSU"). Exemplary PPSUs include RADEL R-5800 NT available from SOLVAY SPECIALTY POLYMERS. In some embodiments, the polyimide or polysulfone is the second homopolymer.
[0103] In some embodiments, the articular layer 58 is comprised of a composite material including a homopolymer blend of at least two or at least three homopolymers. In some embodiments, the homopolymer blend includes a polyaromatic ether and a polyimide. In some embodiments, the homopolymer blend consists of, or consists essentially of, a polyaromatic ether, such as PEEK and PEI. In some embodiments, the homopolymer blend includes a polyaromatic ether and a polysulfone. In some embodiments, the homopolymer blend consists of, or consists essentially of, a polyaromatic ether, such as PEEK and PPSU.
[0104] In some embodiments, the articular layer 58 is comprised of a composite material including a homopolymer blend including a first homopolymer and a second homopolymer. In an exemplary embodiment, the articular layer 58 includes about 50% by weight of the first homopolymer and about 50% by weight of the second homopolymer, about 60% by weight of the first homopolymer and about 40% by weight of the second homopolymer, about 70% by weight of the first homopolymer and about 30% by weight of the second homopolymer, about 75% by weight of the first homopolymer and about 25% by weight of the second homopolymer, about 80% by weight of the first homopolymer and about 20% by weight of the second homopolymer, about 85% by weight of the first homopolymer and about 15% by weight of the second homopolymer, about 88% by weight of the first homopolymer and about 12% by weight of the second homopolymer, about 90% by weight of the first homopolymer and about 10% by weight of the second homopolymer, or about 95% by weight of the first homopolymer and about 5% by weight of the second homopolymer. In an exemplary embodiment, the first homopolymer can be a polycyclic aromatic ether and the second homopolymer can be a polysulfone or a polyimide. In an exemplary embodiment, the first homopolymer is PEEK. In an exemplary embodiment, the second homopolymer is PPSU or PEI. In some embodiments, the first homopolymer is PEEK and the second homopolymer is PPSU. In some embodiments, the first homopolymer is PEEK and the second homopolymer is PEI.
[0105] In some embodiments, the homopolymer is a blend of PEI and PEEK. This may be referred to as PEI / PEEK. In some embodiments, the PEI / PEEK homopolymer blend includes at least about 5% by weight or at least about 10% by weight PEI. In some embodiments, the PEI / PEEK homopolymer blend includes up to about 90% by weight or up to about 95% by weight PEEK. Some embodiments include about 5% PEI and about 95% PEEK, about 10% PEI and about 90% PEEK, about 12% PEI and about 88% PEEK, about 15% PEI and about 85% PEEK, and about 20% PEI and about 80% PEEK.
[0106] In some embodiments, the homopolymer blend is a combination of PPSU and PEEK. This may be referred to as PPSU / PEEK. In some embodiments, the PPSU / PEEK homopolymer blend includes at least about 5% by weight or at least about 10% by weight PPSU. In some embodiments, the PPSU / PEEK homopolymer blend includes less than about 20% by weight or less than about 15% by weight PPSU. In some embodiments, the PPSU / PEEK homopolymer blend includes up to about 85% by weight, up to about 90% by weight PEEK, or up to about 95% by weight PEEK. Some embodiments include about 5% PPSU and about 95% PEEK, about 10% PPSU and about 90% PEEK, about 12% PPSU and about 88% PEEK, about 15% PPSU and about 85% PEEK, and about 20% PPSU and about 80% PEEK.
[0107] In some embodiments, the articular layer 58 has a yield strength as measured by ASTM D638. In exemplary embodiments, the yield strength of the articular layer 58 is in the range of about 100 MPa to about 220 MPa. In some embodiments, the yield strength of the articular layer 58 is at least about 100 MPa, at least about 102 MPa, or at least about 103 MPa. In some embodiments, the yield strength of the articular layer 58 is at least about 100 MPa or at least about 125 MPa. In some embodiments, the yield strength is about 100 MPa to about 150 MPa or about 102 MPa to about 150 MPa. In some embodiments, the yield strength is about 115 MPa to about 220 MPa, about 150 MPa to about 220 MPa, or about 175 MPa to about 220 MPa. In some embodiments, the articular layer 58 has a yield strength of about 99 MPa to about 104.5 MPa, about 100 MPa to about 103.5 MPa, or about 102 MPa to about 104 MPa. In some embodiments, the articular layer 58 has a yield strength of about 189 MPa to about 191.5 MPa, about 189.5 MPa to about 191 MPa, or about 189.5 MPa to about 190.5 MPa. In some embodiments, the articular layer 58 has a yield strength of about 199 MPa to about 201 MPa, about 199.5 to about 200.5 MPa, or about 200 MPa.
[0108] In some embodiments, the articular layer 58 has a tensile modulus measured by ASTM D638. In exemplary embodiments, the tensile modulus of the articular layer 58 is in the range of about 3,000 MPa to about 30,000 MPa or about 3,500 MPa to about 30,000 MPa. In some embodiments, the tensile modulus of the articular layer 58 is at least about 3,000 MPa, at least about 4,000 MPa, at least about 4,100 MPa, or at least about 4,300 MPa. In some embodiments, the articular layer 58 has a tensile modulus of about 3,000 MPa to about 30,000 MPa, about 3,000 MPa to about 10,000 MPa, about 4,000 MPa to about 10,000 MPa, about 4,100 MPa to about 10,000 MPa, about 4,200 MPa to about 10,000 MPa, or about 4,500 MPa to about 6,000 MPa. In some embodiments, the articular layer 58 has a tensile modulus of about 5,500 MPa to about 24,000 MPa, about 5,500 MPa to about 18,000 MPa, about 5,500 MPa to about 13,000 MPa, or about 5,500 MPa to about 10,800 MPa. In some embodiments, the articular layer 58 has a tensile modulus of about 6,800 MPa to about 10,500 MPa, about 6,900 MPa to about 7,900 MPa, or about 6,900 MPa to about 7,700 MPa.
[0109] In some embodiments, the articular layer 58 has an IZOD impact toughness as measured by ASTM D4812. Illustratively, the articular layer 58 has an IZOD impact toughness of at least 5 J / m 2 In an exemplary embodiment, the toughness of the articular layer 58 is about 5 J / m 2 ~about 10J / m 2 , about 5.2J / m 2 ~about 10J / m 2 , about 5.2J / m 2 ~about 8J / m 2 , or about 5.3 J / m 2 ~about 8J / m 2 is within the range.
[0110] In some embodiments, the articular layer 58 has a compressive yield as measured by ASTM D695. Illustratively, the articular layer 58 has a compressive yield of at least about 50 MPa, at least about 110 MPa, at least about 115 MPa, or at least about 120 MPa. In some embodiments, the compressive yield is between about 50 MPa and about 150 MPa, or between about 110 MPa and about 150 MPa.
[0111] In some embodiments, the articular layer 58 has fatigue behavior measured using ASTM D3479 / D3479M tensile-tensile fatigue test. In some embodiments, each cycle of the fatigue test at a given stress level is performed at 2 Hertz and 5 million cycles. In some embodiments, an articular layer 58 made of a blend of homopolymers or a blend of PEEK and another polymer performs better than an articular layer 58 made of a single homopolymer. In some embodiments, the fatigue strength is at least about 60 MPa or at least about 70 MPa.
[0112] The wear rate of the articular layer 58 can be measured by contacting the articular layer 58 with a material. In an exemplary embodiment, the wear rate of the articular layer 58 is measured by contacting the articular layer 58 with a polyethylene, such as cross-linked ultra-high molecular weight polyethylene available as XLK ultra-high molecular weight polyethylene. In some embodiments, the articular layer 58 has a wear rate of less than about 10, less than about 8, less than about 6, or less than about 4 mg / million cycles (MC). In some embodiments, the wear rate of the articular layer 58 is in the range of about 0.5 mg / MC to about 10 mg / MC. In some embodiments, the wear rate is about 1.5 mg / MC to about 7 mg / MC or about 1.5 mg / MC to about 4 mg / MC.
[0113] In the exemplary embodiment, the articular layer 58 is secured to a support layer 60. The support layer 60 is configured to extend between the articular layer 58 and the patient's surgically repaired femur.
[0114] In an exemplary embodiment, support layer 60 is comprised of a composite material including (i) a homopolymer, copolymer, or mixtures thereof, and (ii) reinforcing fibers.
[0115] In some embodiments, the support layer 60 comprises a homopolymer, a copolymer, or a mixture thereof. In some embodiments, the support layer 60 comprises a homopolymer. In some embodiments, the support layer 60 comprises a copolymer. In some embodiments, the support layer 60 comprises a composite material comprising a homopolymer and reinforcing fibers. In some embodiments, the support layer 60 comprises a composite material comprising a copolymer and reinforcing fibers. In some embodiments, the support layer 60 comprises a composite material consisting of, or consisting essentially of, a homopolymer and reinforcing fibers. In some embodiments, the support layer 60 comprises a composite material consisting of, or consisting essentially of, a copolymer and reinforcing fibers. In some embodiments, the support layer 60 comprises reinforcing particles, such as barium sulfate. In some embodiments, the supper layer 60 does not include reinforcing fibers or particles.
[0116] In some embodiments, the support layer 60 comprises a copolymer. In some embodiments, the support layer 60 comprises a polyacetal. In some embodiments, the support layer 60 comprises a polyacetal copolymer. In some embodiments, the copolymer polyacetal is a polyoxymethylene copolymer (or commonly referred to as "POM"). Exemplary POM copolymers include Hostaform, MT12U03, or MT2U06 available from CELANESE.
[0117] In exemplary embodiments, the support layer 60 comprises at least about 50%, at least about 60%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, or at least about 95% by weight of the copolymer. In these exemplary embodiments, the copolymer can be a polyacetal, such as POM.
[0118] In some embodiments, the support layer 60 comprises a homopolymer. In some embodiments, the support layer 60 comprises a polycyclic aromatic ether. In some embodiments, the support layer 60 comprises PEEK.
[0119] In exemplary embodiments, support layer 60 comprises at least about 50%, at least about 60%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, or at least about 95% by weight of a homopolymer. In these exemplary embodiments, the homopolymer can be a polycyclic aromatic ether, such as PEEK.
[0120] In some embodiments, the support layer 60 includes reinforcing fibers. The reinforcing fibers may be distributed throughout the support layer 60. Exemplary reinforcing fibers include glass fiber or carbon fiber. In some embodiments, the support layer 60 includes carbon fiber reinforced (CFR) PEEK. Exemplary CFR PEEK is available from SOLVAY SPECIALTY POLYMERS. In some embodiments, the support layer 60 includes glass fiber reinforced (GFR) polyacetal. In other embodiments, the support layer 60 does not include reinforcing fibers.
[0121] In some embodiments, the support layer 60 has a yield strength as measured by ASTM D 638. In exemplary embodiments, the yield strength of the support layer 60 is in the range of about 50 MPa to about 150 MPa. In some embodiments, the yield strength of the support layer 60 is at least about 50 MPa or at least about 75 MPa. In some embodiments, the yield strength is about 50 MPa to about 200 MPa, about 50 MPa to about 150 MPa, or about 50 MPa to about 125 MPa.
[0122] In some embodiments, the support layer 60 has a Young's modulus as measured by ASTM D 638. In exemplary embodiments, the Young's modulus of the support layer 60 is in the range of about 3,500 MPa to about 30,000 MPa. In some embodiments, the Young's modulus of the support layer 60 is at least about 3,000 MPa, at least about 5,000 MPa, at least about 10,000 MPa, or at least about 15,000 MPa. In some embodiments, the support layer 60 has a Young's modulus of about 3,500 MPa to about 30,000 MPa, about 5,500 MPa to about 25,000 MPa, or about 5,500 MPa to about 23,000 MPa.
[0123] In other embodiments, the femoral component 12 is comprised of a single composition such that the femoral component 12 is monolithic. In an exemplary embodiment, the femoral component 12 is comprised of a single composition including a homopolymer, a copolymer, or a mixture thereof. In some embodiments, the femoral component 12 is comprised of a single composition including a blend of at least two homopolymers. In some embodiments, the homopolymer is a polycyclic aromatic ether, preferably PEEK. In some embodiments, the homopolymer is a polyacetal, preferably POM. In some embodiments, the femoral component 12 is comprised of a single composition including a blend of a polycyclic aromatic ether, preferably PEEK, and a second homopolymer, preferably PPSU, PEI, or a mixture thereof. Illustratively, a femoral component comprised of a single composition does not include reinforcing fibers.
[0124] In an exemplary process, the femoral component 12 may be constructed by molding the articular layer 58 and the support layer 60 together. In some embodiments, the articular layer 58 is overmolded onto the support layer 60. The process may be injection molding or compression molding. Interfacial adhesion between the layers may be enhanced during the process by chemically exploiting a physical interlocking design and / or chemical compatibility between the polymers, for example, between PEEK and PEI.
[0125] In some embodiments, the process of forming the orthopaedic implant includes molding material to form a support layer 60. In an exemplary embodiment, the process further includes overmolding material and forming an articular layer 58 on the support layer 60 to form a molded blank. In an exemplary embodiment, the process further includes finishing the molded blank into an orthopaedic implant. In an exemplary embodiment, the process forms a femoral component of a knee implant. In some embodiments, the composite material forms an acetabular bearing adapted to be implanted in a patient's acetabulum. In another exemplary embodiment, the composite material forms a glenoid bearing adapted to be implanted in a patient's glenoid cavity. In another exemplary embodiment, the composite material forms a tibial bearing adapted to be implanted in a patient's tibia.
[0126] In one embodiment, the orthopedic implant includes an articular layer 58 and a support layer 60 arranged to contact the articular layer 58. The articular layer 58 is comprised of a blend of polyaryletherketone and polyimide, preferably a blend of PEEK and PEI. The polyaryletherketone, preferably PEEK, is present at least 80% by weight, and preferably at least 85% by weight, and the polyimide, preferably PEI, is present at less than 20% by weight, and preferably less than 15% by weight. The articular layer 58 has a yield strength of at least about 100 MPa, at least about 102 MPa. The articular layer 58 has a tensile modulus of at least 3,000 MPa, preferably at least 4,000 MPa, and preferably at least 4,100 MPa. The articular layer 58 has a compressive yield of at least about 110 MPa, preferably at least about 115 MPa, or more preferably at least about 120 MPa. The IZOD toughness is at least 5 J / m 2 or about 5.3 J / m 2 ~about 8J / m 2The wear rate is less than about 10, preferably less than about 6, or preferably less than about 4 mg / million cycles (MC). The support layer 60 is composed of a polymer such as polyacetal or polyaryletherketone, and optionally contains reinforcing fibers such as carbon or glass fibers, or reinforcing particles such as barium sulfate.
[0127] In one embodiment, the orthopedic implant includes an articular layer 58 and a support layer 60 arranged to contact the articular layer 58. The articular layer 58 is comprised of a blend of polyaryletherketone and polysulfone, preferably a blend of PEEK and PPSU. The polyaryletherketone, preferably PEEK, is present at least 80% by weight, and preferably at least 85% by weight, and the polysulfone, preferably PPSU, is present at less than 20% by weight, and preferably less than 15% by weight. The articular layer 58 has a tensile modulus of at least 3,000 MPa, preferably at least 3,500 MPa. The articular layer 58 has a compressive yield of at least about 100 MPa, preferably at least about 105 MPa, or more preferably at least about 110 MPa. The IZOD toughness is at least 5 J / m 2 or about 5.3 J / m 2 ~about 8J / m 2 The wear rate is less than about 10, preferably less than about 6, or preferably less than about 4 mg / million cycles (MC). The support layer 60 is composed of a polymer such as polyacetal or polyaryletherketone, and optionally contains reinforcing fibers such as carbon or glass fibers, or reinforcing particles such as barium sulfate. EXAMPLES
[0128] Example 1 Tensile properties Five different types of test coupons were prepared and their tensile properties were tested. The results are shown in Figures 3-6. The formulations are shown below. Percentages, if present, are weight percent. Ten coupons of each type of formulation were prepared and tested. Tensile testing was performed according to the method specified in ASTM D638 using Type 1 dog-bone specimens. The displacement rate was 5 mm / min until the displacement reached 0.5 mm, after which the specimens were tested to failure at a rate of 50.5 mm / min.
[0129] PEEK coupons were formed from molding Ketaspire KT-880 NT.
[0130] POM coupons were formed from molding Hostaform MT12U03.
[0131] 90% Ketaspire KT-880 NT and 10% ColorRX PEI 1600 RX were blended and molded to form a 90PEEK / 10PEI coupon.
[0132] 80% Ketaspire KT-880 NT and 20% ColorRX PEI 1600 RX were blended and molded to form an 80PEEK / 20PEI coupon.
[0133] A 90PEEK / 10PPSU coupon was formed by blending 90% Ketaspire KT-880 NT with 10% Radel R5800 NT.
[0134] 95% Ketaspire KT-880 NT and 5% ColorRX PEI 1600 RX were blended and molded to form a 95PEEK / 5PEI coupon.
[0135] The tensile strength of the coupons was measured according to ASTM D638, and the results are shown in Figure 3.
[0136] The tensile modulus of the coupons was measured according to ASTM D638, and the results are shown in FIG.
[0137] The compressive strength of the coupons was measured according to ASTM D695. The loading rate was 1.3 mm / min and the test was run until a strain of 20% was reached. The results are shown in Figure 5.
[0138] IZOD impact toughness was measured according to ASTM D4812. The pendulum weight was set to produce an impact energy of 11 Joules. The results are shown in Figure 6.
[0139] Example 2 The coupons were injection molded and tested for wear performance. The tests evaluated the wear performance of XLK pins on PEEK coupons, PEEK / PPSU coupons, PEEK / PEI coupons, and POM coupons with (phase 1) and without (phase 2) scratching of the coupons. The wear rates of the pins and coupons from both phase 1 and phase 2 are summarized in Figure 7. The wear rates of the XLK pins or coupons were not significantly different for each sample type (i.e., POM phase 1 vs. phase 2) before (phase 1) and after (phase 2) scratching of the coupons. Figure 8 summarizes the average roughness Sa of the four groups over the study period. The disks were scratched in phase 2 of the test after 1.98 MC intervals. The 2.31 MC interval data points are roughness measurements after scratching of the coupons and before phase 2 of the test.
[0140] Hostaform POM, KT-880-NT neat PEEK (Solvay), PEEK / 10% PPSU, and PEEK / 20% PEI coupons were injection molded. The coupons were used as-molded and not sterilized, except for the elimination of gates and flashing, and the addition of two through-holes to align with the test fixture. The coupons were approximately 1.38 inches in diameter and 0.17 inches thick, and were mounted in a custom fabricated POD fixture.
[0141] XLK polyethylene pins were used for the wear tests. The articulating end of each pin had a fly-cut surface topography machined into it. All pins had a diameter of 0.39 inches and a length of 0.9 inches. Eleven XLK pins were used for the wear tests and three were used as immersion controls (no load).
[0142] Testing was performed using a Paul type load with a maximum load of 330 N and 1.98 million cycles (MC) in fetal bovine serum lubricant. Gravimetric evaluation of the specimens was performed to calculate the wear at each interval using immersion controls according to WI-6071.
[0143] The pin was moved in a 10 mm x 10 mm (XY) square pattern. The Paul duty cycle (J. Paul, Proc. Inst. Mech. Eng., 181, 8-15, 1967) was applied with a peak of 330 N and a frequency of 1.6 Hz.
[0144] Each data collection interval was 0.33 million cycles (MC). At the end of each interval, the used lubricant was discarded and fresh lubricant was added.
[0145] Each sample pair (polypin+disk) was rotated at a new station for each interval.
[0146] Bovine serum (HyClone Laboratories Inc., Logan UT, Lot #AC10256479) was diluted to 90% (total protein concentration 62.1 mg / mL) according to WI-0536. Serum contained 0.2% sodium azide and 20 mM EDTA as a preservative and calcium phosphate stabilizer, respectively.
[0147] The polyethylene pins were cleaned before the start of the test and between each interval.
[0148] The pins and disks were not pre-soaked prior to testing. The pins and disks were stored in RO water at room temperature between Phase 1 and Phase 2 of the test.
[0149] Data collected after each testing interval: Gravimetric weighing of the pins was performed using an XPE205 balance (Mettler Toledo, Columbus OH, gauge #9009170060000) conforming to 103499701. Gravimetric weighing of the disks was performed using an XP205 balance (Mettler Toledo, Columbus OH, gauge #9009140060000) conforming to WI-6071.
[0150] Non-contact interferometric measurements were performed on the disks using a Zygo NewView 8300 (Middlefield CT, gage #2077520050000) at the start of the test and after each interval. Feedback data was collected and stored at each interval. Wear rates were calculated using best fit linear regression through the data excluding the 0 cycle, 0 wear data point. Exclusion of data from this analysis was accompanied by evidence supporting an assignable cause. Statistical comparison of XLK pin and disk average wear rates was performed using one-way ANOVA with Tukey comparison test (α=0.2).
[0151] Phase 1 Results Figures 9 and 10 summarize the average cumulative wear data. Figure 9 shows the pin wear rate. Figure 10 shows the disk wear rate. The disk counter surface roughness using a Zygo interferometer is summarized in Figure 11.
[0152] Phase 2 Results: Figures 12 and 13 summarize the average cumulative wear data. Figure 12 shows the wear of the pin on the disk. Figure 13 shows the wear of the disk. Figure 14 shows the total loss from the disk and pin pair. The facing surface roughness of the disk using a Zygo interferometer is summarized in Figure 15.
[0153] The wear rates (in mg / MC (MC=million cycles)) (±80% CI) and statistical results (commonalities=statistically equivalent) for the four sample groupings (mean ±80% CI) are provided in Table 1.
[0154] [Table 1]
[0155] Example 3 Fatigue Testing Tensile-tensile fatigue testing of the dogbone specimens described in Figure 1 was performed according to ASTM D3479 / D3479M. Each cycle at a given stress level was performed at 2 Hertz and 5 million cycles. Discs made from PEEK, PEEK with 10% PEI, and PEEK with 10% PPSU were analyzed. The results are shown in Figure 16.
[0156] As noted above, other orthopaedic components may be designed and fabricated in a manner similar to the femoral component 12. For example, as shown in Figures 17 and 18, a glenoid component 70 of a shoulder prosthesis may include an articular layer 58 and a support layer 60. Although not shown, a humeral component of a reverse shoulder prosthesis may also be designed and fabricated with an articular layer 58 and a support layer 60.
[0157] 19 and 20, the acetabular component 72 of the hip prosthesis may include an articular layer 58 and a support layer 60. It should be appreciated that such an acetabular cup 72 may be configured for implantation within a patient's acetabulum with or without the use of a separate acetabular shell.
[0158] 21 and 22 , the tibial component 14 may be designed and fabricated with an articular layer 58 and a bearing layer 60. It should be understood that such an embodiment of the tibial component 12 may be configured for implantation within a patient's tibia with or without the use of a tibial tray 16.
[0159] 23 and 24, the head component 74 of either the hip or shoulder prosthesis may be designed and fabricated with an articular layer 58 and a support layer 60. Although not shown, the glenosphere component of a reverse shoulder prosthesis may also be designed and fabricated with an articular layer 58 and a support layer 60.
[0160] Additional examples of orthopedic components that may be designed and fabricated using the articular layer 58 and support layer 60 are shown in Figures 17-24, although other orthopedic components may also be designed and fabricated in this manner including hip stems, humeral components of shoulder prostheses, ankle prosthesis components, distal prosthesis components, and the like.
[0161] While the present disclosure has been illustrated and described in detail in the drawings and foregoing description, it is understood that such illustration and description is merely illustrative in nature and should not be regarded as restrictive, and that merely illustrative embodiments have been shown and described, and that all changes and modifications that come within the spirit of the disclosure are desired to be protected.
[0162] There are several advantages of the present disclosure that derive from the various features of the devices, systems, and methods described herein. It should be noted that alternative embodiments of the devices, systems, and methods of the present disclosure may not include all of the features described, but still benefit from at least some of the advantages of such features. Those skilled in the art may readily devise their own implementations of the devices, systems, and methods that incorporate one or more of the features of the present invention and are within the spirit and scope of the present disclosure.
[0163] [Embodiment] (1) An orthopedic knee prosthesis system, comprising: a tibial component configured to be implanted into a proximal end of a patient's tibia, the tibial component including a concave bearing surface; a femoral component configured to be implanted into a distal end of a patient's femur, the femoral component including femoral condyles having (i) an articular layer including an articular surface curved in a sagittal plane and configured to articulate with the concave bearing surface of the tibial component, and (ii) a support layer positioned opposite the articular surface and including a bone-facing surface configured to engage the distal end of the patient's femur; the articular layer of the femoral component comprises a polyetheretherketone (PEEK) homopolymer; The orthopaedic knee prosthesis system, wherein the support layer comprises: (i) reinforcing fibers; and (ii) a homopolymer, a copolymer, or a mixture thereof. (2) The orthopedic prosthesis system of claim 1, wherein the articular layer further comprises a polysulfone, a polyimide, or a mixture thereof. (3) The orthopedic prosthesis system of claim 2, wherein the PEEK is about 75% to about 95% by weight of the articular layer. (4) The orthopedic prosthesis system of claim 1, wherein the support layer comprises a polycyclic aromatic ether homopolymer. (5) The orthopedic prosthesis system of claim 1, wherein the support layer comprises a polyacetal copolymer.
[0164] (6) The orthopedic prosthesis system of claim 5, wherein the polyacetal copolymer is a polyoxymethylene copolymer. (7) The orthopedic prosthesis system of claim 6, wherein the support layer comprises at least about 80% polyoxymethylene. (8) The orthopedic prosthesis system of claim 6, wherein the reinforcing fibers are glass fibers or carbon fibers. (9) An orthopedic knee prosthesis, comprising: a femoral component including femoral condyles having (i) an articular layer including an articular surface curved in a sagittal plane and configured to engage with a tibial component, and (ii) a support layer positioned opposite the articular surface and including a bone-facing surface configured to engage a distal end of a patient's femur; the articular layer is comprised of a composite material including a blend of polyetheretherketone (PEEK) homopolymer with polysulfone, polyimide, or a mixture thereof; An orthopaedic knee prosthesis, wherein the articular layer has a yield strength of at least about 100 MPa. (10) The orthopedic knee prosthesis of claim 9, wherein the articular layer is substantially free of fibers.
[0165] (11) The orthopedic knee prosthesis of claim 10, wherein the articular layer has a tensile modulus of at least about 4,000 MPa. (12) The articular layer has a resistance of at least 5 J / m 2 12. The orthopedic knee prosthesis of embodiment 11, having an IZOD toughness of 1. (13) The orthopedic knee prosthesis of claim 9, wherein the PEEK is about 75% to about 95% by weight of the articular layer. (14) An orthopedic knee prosthesis, comprising: a femoral component including femoral condyles having (i) an articular layer including an articular surface curved in a sagittal plane and configured to engage with a tibial component, and (ii) a support layer positioned opposite the articular surface and including a bone-facing surface configured to engage a distal end of a patient's femur; The support layer comprises: (i) a homopolymer, a copolymer, or a mixture thereof; and (ii) reinforcing fibers; The orthopedic knee prosthesis, wherein the support layer has a tensile modulus of about 3,000 MPa to about 30,000 MPa. (15) The orthopedic knee prosthesis of claim 14, wherein the support layer comprises a polyoxymethylene copolymer.
[0166] (16) The orthopedic knee prosthesis of claim 14, wherein the support layer comprises a polycyclic aromatic ether. (17) An orthopedic knee prosthesis, comprising: a femoral component including femoral condyles having (i) an articular layer including an articular surface curved in a sagittal plane and configured to engage with a tibial component, and (ii) a support layer positioned opposite the articular surface and including a bone-facing surface configured to engage a distal end of a patient's femur; the articular layer of the femoral component comprises a homopolymer; The orthopaedic knee prosthesis, wherein the support layer comprises a copolymer and a reinforcing fiber. (18) The orthopedic knee prosthesis of claim 17, wherein the homopolymer of the articular layer is a polycyclic aromatic ether or a polyacetal. (19) The orthopedic knee prosthesis of embodiment 18, wherein the articular layer comprises a polyacetal copolymer. (20) The orthopedic knee prosthesis of claim 19, wherein the polyacetal copolymer is a polyoxymethylene copolymer.
[0167] (21) The orthopedic knee prosthesis of claim 20, wherein the articular layer comprises at least about 80% polyoxymethylene copolymer. (22) The orthopedic knee prosthesis of claim 18, wherein the polycyclic aromatic ether is polyetheretherketone (PEEK). (23) The orthopedic knee prosthesis of claim 22, wherein the PEEK is about 75% to about 95% by weight of the articular layer. (24) A method of making an implantable component for an orthopedic prosthesis, comprising the steps of: molding a first layer of polymeric material to a second layer of polymeric material to form a composite material; forming the composite material into a predetermined shape of the implantable component, the implantable component having an articular layer and a support layer; The method, wherein the articular layer comprises a homopolymer and the support layer comprises a polymer and reinforcing fibers. (25) The method of embodiment 24, wherein forming the implantable component is an acetabular bearing adapted to be implanted in the patient's acetabulum.
[0168] (26) The method of embodiment 24, wherein the implantable component is a glenoid bearing adapted to be implanted in the patient's glenoid cavity. (27) The method of embodiment 24, wherein the implantable component is a tibial bearing adapted to be implanted in the patient's tibia. 28. The method of claim 24, wherein the homopolymer of the articular layer comprises a polyetheretherketone (PEEK) homopolymer. 29. The method of claim 28, wherein the articular layer further comprises a polysulfone, a polyimide, or a mixture thereof. (30) The method of embodiment 29, wherein the PEEK is about 75% to about 95% by weight of the articular layer.
[0169] (31) A method for making a femoral component of a knee prosthesis, comprising: molding a first layer of polymeric material to a second layer of polymeric material to form a composite material; forming the composite material into a predetermined shape of the femoral component, the femoral component having an articular layer and a bearing layer; The method, wherein the articular layer comprises a homopolymer and the support layer comprises a polymer and reinforcing fibers. (32) A method of forming a femoral component of a knee prosthesis, comprising: Molding the articular layer and the support layer together to form a composite material; forming the composite material into a predetermined shape of the femoral component; The method of claim 1, wherein the articular layer is comprised of a first polymeric material comprising a blend of homopolymers, and the support layer comprises a second polymeric material different from the first polymeric material and comprising reinforcing fibers. 33. The method of claim 32, wherein the first polymeric material comprises a polysulfone, a polyimide, or a mixture thereof. 34. The method of claim 32, wherein the homopolymer of the articular layer is a polycyclic aromatic ether or a polyacetal. (35) The method of embodiment 34, wherein the polycyclic aromatic ether is polyetheretherketone (PEEK).
[0170] 36. The method of claim 32, wherein the support layer comprises a copolymer and a reinforcing fiber. 37. The method of claim 36, wherein the copolymer of the support layer is a polyacetal. 38. The method of claim 37, wherein the polyacetal is polyoxymethylene. (39) A method of forming a first component for an orthopedic implant, comprising the steps of: co-molding a composite of a first polymeric material comprising a polycyclic aromatic ether and a second polymeric material comprising a polymer and reinforcing fibers; forming the composite material into a predetermined shape of the first component; The method, wherein the first polymeric material is configured to engage a second component of the orthopedic implant and the second polymeric material is configured to engage bone. 40. The method of claim 39, wherein the first polymeric material comprises a homopolymer, a copolymer, or a mixture thereof.
[0171] 41. The method of claim 40, wherein the homopolymer of the first polymeric material is a polycyclic aromatic ether. 42. The method of claim 41, wherein the first polymeric material further comprises a polysulfone, a polyimide, or a mixture thereof. (43) The method of embodiment 42, wherein the polycyclic aromatic ether is polyetheretherketone (PEEK). 44. The method of claim 43, wherein the polymer of the second polymeric material comprises a copolymer. 45. The method of claim 44, wherein the copolymer of the second polymeric material is a polyacetal.
[0172] (46) The method of embodiment 45, wherein the polyacetal is polyoxymethylene. (47) The method of embodiment 39, wherein forming the composite material includes molding the composite material into an acetabular bearing adapted to be implanted in the patient's acetabulum. (48) The method of embodiment 39, wherein forming the composite material includes molding the composite material into a glenoid bearing adapted to be implanted in a glenoid cavity of the patient. (49) The method of embodiment 39, wherein forming the composite material includes molding the composite material into a tibial bearing adapted to be implanted in the patient's tibia. (50) An orthopedic knee prosthesis, comprising: a femoral component including a femoral condyle having an articular surface curved in a sagittal plane and configured to engage the tibial component, and a bone-facing surface positioned opposite the articular surface and configured to engage a distal end of a patient's femur; the femoral component comprises at least about 50% by weight of a homopolymer or a blend of a homopolymer with a polysulfone, a polyimide, or a mixture thereof; An orthopaedic knee prosthesis, wherein the femoral component has a yield strength of at least about 100 MPa.
[0173] (51) The orthopedic knee prosthesis of embodiment 50, wherein the homopolymer is a polycyclic aromatic ether or a polyacetal. (52) The orthopedic knee prosthesis of embodiment 51, wherein the polycyclic aromatic ether is polyetheretherketone (PEEK). (53) The orthopedic knee prosthesis of claim 52, wherein the PEEK is about 75% to about 95% by weight of the femoral component. (54) The orthopedic knee prosthesis of embodiment 51, wherein the polyacetal is polyoxymethylene.
Claims
1. 1. An orthopaedic knee prosthesis system comprising: a tibial component configured to be implanted into a proximal end of a patient's tibia, the tibial component including a concave bearing surface; a femoral component configured to be implanted into a distal end of a patient's femur, the femoral component including femoral condyles having: (i) an articular layer including an articular surface curved in a sagittal plane and configured to articulate with the concave bearing surface of the tibial component; and (ii) a support layer positioned opposite the articular surface and including a bone-facing surface configured to engage the distal end of the patient's femur; the articular layer of the femoral component comprises: (i) a polyetheretherketone (PEEK) homopolymer; and (ii) a polysulfone, a polyimide, or a mixture thereof; The orthopaedic knee prosthesis system, wherein the support layer comprises: (i) reinforcing fibers; and (ii) a homopolymer, a copolymer, or a mixture thereof.
2. The orthopedic knee prosthesis system of claim 1, wherein the articular layer comprises a polyetheretherketone (PEEK) homopolymer and a polyetherimide.
3. The orthopaedic knee prosthesis system of claim 1 , wherein the PEEK is about 75% to about 95% by weight of the articular layer.
4. The orthopaedic knee prosthesis system of claim 1 , wherein the support layer comprises a polycyclic aromatic ether homopolymer.
5. The orthopaedic knee prosthesis system of claim 1 , wherein the support layer comprises a polyacetal copolymer.
6. The orthopaedic knee prosthesis system of claim 5 , wherein the polyacetal copolymer is a polyoxymethylene copolymer.
7. The orthopaedic knee prosthesis system of claim 6 , wherein the support layer comprises at least about 80% polyoxymethylene.
8. The orthopaedic knee prosthesis system of claim 6 , wherein the reinforcing fibers are glass fibers or carbon fibers.
9. The orthopedic knee prosthesis system of claim 2, wherein the articular layer is overmolded onto the support layer.
10. The orthopedic knee prosthesis system of claim 9, wherein the articular layer is injection molded or compression molded onto the support layer.
Citation Information
Patent Citations
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