Patent Grant
10543094
The present invention relates generally to orthopaedic medicine. More particularly, the present invention relates to an orthopaedic medicine where natural articulating joints such as knees, hips, shoulders, elbows, wrists, ankles, fingers and spinal elements are replaced by implanted mechanical devices to restore diseased or injured skeletal tissue.
When mechanical devices such as prosthetic knees, hips, shoulders, fingers, elbows, wrists, ankles, fingers and spinal elements are implanted in the body and used as articulating elements they are subjected to wear and corrosion. These prosthetic (orthopaedic) implants are usually fabricated in modular form with the individual elements manufactured from metallic materials such as stainless steels, Co—Cr—Mo alloys, Zr alloys, and Ti alloys (Ti—Al—V); plastics such as ultra high molecular weight polyethylene (UHMWPE); or ceramics such as alumina and zirconia.
As the articulating surfaces of these orthopaedic implants wear and corrode, products including polyethylene wear particles, metallic wear particles, and metallic ions are typically released into the body. Thereafter, these wear particles may be transported to and absorbed into bone, blood, lymphatic tissue, and other organ systems. In general, these wear particles have adverse effects. For example, the polyethylene wear particles have been shown to produce long-term bone loss and loosening of the implant. In addition, even very low concentrations of metallic wear particles and metallic ions may have adverse immunologic tissue reactions. Accordingly, it is desirable to provide an orthopaedic implant that is capable of overcoming the disadvantages described herein at least to some extent.
The foregoing needs are met, to a great extent, by the present invention, wherein in one aspect an orthopaedic implant is provided that in some embodiments provides reduced wear and increased fracture and fatigue resistance in comparison with some existing orthopaedic implants.
An embodiment of the present invention pertains to an orthopaedic implant to replace a joint in a patient. The orthopaedic implant includes a first component having a first component surface and a second component having a second component surface. The first component surface and the second component surface are configured to mate at an interface. The first component surface includes a metal substrate, a nanotextured surface, a ceramic coating, and a transition zone. The nanotextured surface is disposed directly upon the metal substrate and has surface features in a size of 10−9 meters. The ceramic coating conforms to the nanotextured surface and includes a plurality of bio-active sites configured to attract and retain calcium and phosphorous cations. The transition zone is disposed between the metal substrate and the ceramic coating. The transition zone includes a concentration gradient transitioning from the metal substrate to the ceramic coating and there is no distinct interface between the metal substrate and the ceramic coating. In some examples, the ceramic coating is imbedded to a depth of about 5 nanometers below the nanotextured surface.
Another embodiment of the present invention relates to an orthopaedic implant to replace a joint in a patient. The orthopaedic implant includes a first component and a second component. The first component has a first component surface. The second component has a second component surface. The first component surface and the second component surface are configured to mate at an interface. The first component surface includes: a metal substrate, a nanotextured surface, and a ceramic coating. The nanotextured surface is disposed directly upon the metal substrate having surface features in a size of 10−9 meters. The ceramic coating conforms to the nanotextured surface and includes a plurality of bio-active sites configured to attract and retain calcium and phosphorous cations. At least a portion of the ceramic coating is ballistically imbedded below the nanotextured surface with no distinct interface between the metal substrate and the ceramic coating. In some examples, the ceramic coating is imbedded to a depth of about 5 nanometers below the nanotextured surface.
Yet another embodiment of the present invention pertains to an orthopaedic implant. The orthopaedic implant includes a substrate, nanotextured surface, alloyed case layer, and conformal coating. The nanotextured surface is disposed upon the substrate. The nanotextured surface includes a plurality of bio-active sites. The alloyed case layer is ballistically imbedded on to and below the nanotextured surface. The conformal coating is disposed upon the alloyed case layer. The nanotextured surface, alloyed case layer, and the conformal coating are generated in the presence of a continuous vacuum.
Yet another embodiment of the present invention pertains to an orthopaedic implant. The orthopaedic implant includes a first component and second component. The first component has a first component surface and the second component has a second component surface. The first component and the second component are configured to replace a joint in a patient and the first component surface and the second component surface are configured to mate at an interface. Both the first component and the second component include a substrate, nanotextured surface, alloyed case layer, and conformal coating. The nanotextured surface is disposed upon the substrate. The nanotextured surface includes a plurality of bio-active sites. The alloyed case layer is ballistically imbedded on to and below the nanotextured surface. The conformal coating is disposed upon the alloyed case layer. The nanotextured surface, alloyed case layer, and the conformal coating are generated in the presence of a continuous vacuum.
Yet another embodiment of the present invention pertains to a method of coating a surface of an orthopaedic implant component. In this method, the component is placed into a vacuum chamber. The component has a substrate that is textured to create a nanotextured surface with a plurality of bio-active sites. The bio-active sites are configured to retain a lubricating layer in response to exposure to a bodily fluid and the texturing is accomplished by ion beam sputtering the substrate. In addition, the nanotextured surface is coated so that surface-related properties are made. In this coating step, ions are imbedded into the substrate to generate an alloyed case layer in the substrate and a conformal coating is generated on the alloyed case layer. The texturing and coating steps are performed while maintaining a continuous vacuum in the vacuum chamber.
There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
The performance of orthopaedic implants 10 of all types and particularly those that provide motion when implanted in the body can be improved dramatically through the use of embodiments of the present invention. The surface treatments described herein may reduce the generation of wear debris, corrosion products, and metal ion leaching when applied to orthopaedic implants 10 of various designs and made from a wide variety of materials. Thus, when so-treated, orthopaedic implants 10 used in patients to restore skeletal motion impaired by injury or disease may reduce or eliminate the osteolysis, inflammatory and toxic response, and carcinogenic effects that can adversely affect conventional implants. This reduction in generation of wear debris is achieved by applying coatings to the articulating counterfaces of the implants that are more wear-resistant, corrosion-resistant, and self-lubricating than the various metallic, ceramic, and plastic materials the implants themselves are made from.
According to various embodiments of the invention, surfaces of orthopaedic implants may be treated to reduce wear and improve lubrication. In general, modular orthopaedic implants suitable for use with embodiments of the invention are varied in design and may employ articulating surfaces having different combinations of materials. In some suitable designs, one element may be a metal alloy and the opposed articulating element may be a polymer. In other suitable designs one element may be a metal alloy and the opposed articulating element may be a similar metal alloy. In yet other suitable designs one element may be a ceramic material and the opposed articulating element may be a polymer. And in still another suitable design one element may be a ceramic material and the opposed articulating element may be a similar ceramic material. By treating mating surfaces of the orthopaedic implants as described herein, friction, wear, corrosion, and/or fatigue may be minimized, resulting in a reduced generation of wear debris and metal ion release; and improved lubricity.
Orthopaedic implants treated according to various embodiments of this invention exhibit reduced generation and release of wear particles, corrosion products, and metallic ions into the body. This reduction in non-biologic contaminants results in a reduced inflammatory response of the body to the implant which improves the longevity of the implant residing in the body. The various embodiments of this invention provide an orthopaedic implant that exhibits reduced generation and release of metallic, plastic, and ceramic wear particles; corrosion products; and metallic ions into the body thereby reducing the inflammatory response of the skeletal tissue to the implant. This results in reducing osteolysis leading to loosening of the orthopaedic implant in the bone into which it is implanted, and enhances its longevity.
As described herein, a surface treatment may be applied to either one or both of the articulating opposed surfaces of the implant. The surface treatment provides hardness, wear-resistance and corrosion-resistance, and has self-lubricating features that further help reduce the generation and release of wear debris. This surface treatment may be a coating that is initially alloyed into one or more of the articulating surfaces of the implant to form a transition zone starting below the surface of the substrate and then grown to a finite dimensional thickness from the alloyed surface. This transition zone includes a concentration gradient transitioning from the metal substrate to the ceramic coating that has no distinct interface between the metal substrate and the ceramic coating. This facilitates relatively greater adhesion of the coating to the articulating surfaces of the implant as compared to conventional coatings. As such, delamination of the coating from the treated articulating surfaces of the implant is reduced or eliminated. In addition, the surface treatment provides a self-lubricating property to further reduce wear between the articulating elements. This is achieved by providing biologically active sites on the surface of the coatings that attract and hold natural lubricants such as synovial fluid or other extracellular fluids present in the tissue around the articulating elements. These fluid retentive surfaces act to provide a continuous thin layer of lubrication between the treated articulating elements which reduces or eliminates physical contact between the surfaces of the elements thus reducing or eliminating the generation and release of metallic, plastic, and ceramic wear debris; corrosion products; and metallic ions into the body.
Conventional case hardening and coating methods often undesirably alter the bulk properties of the materials to which they are applied. Specifically, the hardness, toughness, fracture-resistance, and dimensionality may be altered in an undesirable manner by conventional hardening and coating techniques. Post-coating heat-treatments and/or machining may be employed to return the bulk properties to these conventionally treated articles. However, many materials cannot be heat-treated without detrimental effects. Particular examples of materials that cannot be heat treated without detrimental effects include: any of the family of stainless steels, Co—Cr—Mo alloys, Ti—Al—V alloys, Zr alloys; alumina and zirconia ceramics; and plastics. It is an advantage of embodiments of the invention that the bulk properties of the implant material are substantially unaffected by surface treatments as described herein. As such, post-coating heat-treating or machining may be avoided.
The coating provided by the various surface treatments described herein may be applied to a metal substrate. These coatings include hard ceramic material such as aluminum oxide (Al2O3, alpha phase), zirconium oxide (Zr2O), metallic nitrides (such as TiN, Si3N4, CrN, ZrN, TaN), and/or metallic carbides (such as Cr2C, TiC, WC). The use of these and other hard ceramic materials further reduces abrasion of the coating. In this manner, orthopaedic implants 10 that have high bulk fracture/fatigue-resistant properties characteristic of metallic materials, and also have the high surface wear- and corrosion-resistant properties characteristic of hard ceramic materials may be provided by various embodiments of the invention. This is achieved by applying a ceramic material to the articulating surface of a metallic implant which minimizes the chance of catastrophic failure of the implant due to fracture of the bulk material.
The method of treating one or both of the articulating opposed bearing surfaces of the implant as described herein produces a thin nanocrystalline or nearly-amorphous coating that may include multiple contiguous layers of different materials such as metals (Cr, Ni, Ti, Zr, Al, and others) and hard ceramics such as aluminum oxide (Al2O3, alpha phase), zirconium oxide (Zr2O), or metallic nitrides (such as TiN, Si3N4, CrN, ZrN, TaN), or metallic carbides (such as Cr2C, TiC, WC), each grown directly and sequentially from the previously grown layer. In general, this coating process may be carried out at a temperature of 600 degrees Fahrenheit or less. This reduces or eliminates temperature induced changes in bulk properties or dimensions of the treated element. In addition this coating process produces a thin nanocrystalline or nearly-amorphous coating on the articulating surface thereby minimizing the possibility that intergranular cracks or voids in the coating can allow corrosion and subsequent release of metal ions and/or particle wear debris into the patient. Furthermore, this thin nanocrystalline or nearly-amorphous coating on the articulating surface minimizes the possibility that intergranular cracks in the coating can propagate into the underlying substrate to cause it to fail prematurely, as by a fatigue mechanism. It is a further advantage that coating applied as described herein are resistant to the effects of gamma ray sterilization procedures. Thus, the treated implants can sterilized without degrading the wear-resistant, corrosion-resistant, and self-lubricating properties of the treated implant.
The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout.
A variety of combinations of materials are suitable for use with the contacting articulating surfaces of elements in modular orthopaedic hips, knees and other implants according to various embodiments of the invention. These combinations include metal-polymer, ceramic-polymer, metal-metal, and ceramic-ceramic. When treated or coated as described herein, these material combinations reduce friction, wear, and corrosion in modular articulating orthopaedic implants 10. It is an advantage of embodiments of the invention that undesirable particle debris may be reduced or eliminated by the treatments described herein. Particular examples of drawbacks associated with untreated conventional materials are described in Table I and highlight the innovative features of the current invention.
Referring to Table I, it is seen that conventional polymeric materials such as UHMWPE are subject to abrasive, adhesive, and fatigue wear, all of which contribute to the release of polymeric particle debris. In addition the UHMWPE is soft and is subject to bulk plastic deformation and dimensional distortion. The surfaces of metallic components wearing against each other are also subject to abrasive, adhesive and fatigue failure. Abrasive rubbing of opposed metallic surfaces constantly removes passive oxide layers on both metal surfaces which release metal ions that are potentially toxic and carcinogenic. Adhesive wear between the opposed metal surfaces will produce galling and metal transfer with constant generation of particulate metallic particle debris. And under cyclic loading conditions the metal surfaces eventually show fatigue wear. Ceramic materials, when wearing against polymer and metal surfaces exhibit low coefficients of friction and generate relatively low levels of ceramic wear debris. Likewise ceramic elements wearing against each other produce relatively low levels of ceramic wear debris. However, bulk ceramic materials are brittle and subject to fatigue fracture producing large ceramic fragments and possible catastrophic failures.
Furthermore, the IBED process allows a high degree of control over the mechanical and metallurgical properties of the ceramic coatings 76 and 78. The metallurgical composition can be maintained in a highly uniform manner throughout the ceramic coatings. As a result, properties such as hardness and wear-resistance can be optimized to reduce or eliminate wear debris generation from the metallic surface beneath the ceramic coating. The coating grain sizes can further be maintained in the nanometer (1×10−9 meter) range allowing the coatings to grow substantially void- and pinhole-free thus eliminating corrosion and ion leaching from the metallic surface beneath the ceramic coating. The metallurgical composition can also be tailored to provide biologically active sites on the external surfaces (80 and 82) of the ceramic coating that attract and hold natural lubricants (synovial or other extracellular fluids) present in the tissue around the articulating elements. These fluid retentive surfaces provide a continuously forming thin layer of lubrication 58 between the treated articulating elements that reduces or eliminates physical contact between the surfaces of the elements. In this manner, the generation and release of wear debris, corrosion products, and metallic ions into the body is reduced or eliminated.
The IBED process used to form a ceramic coating in and on the surfaces of the metallic articulating elements proceeds as a continuous, uninterrupted, two-step process described in the following Table II:
As shown in
The IBED process used to form a ceramic coating in and on the surfaces of the metallic articulating elements proceeds as a continuous, uninterrupted, two-step process is outlined below in Table III:
If multiple layers of coating material are to be applied, the beam of texturing/augmenting 162 ions is simultaneously applied to the surface of the first coating layer and is used initially to mix or ballistically embed the coating material into the surface of the first coating layer forming an alloyed case layer in the first coating layer, and then used to control the composition and crystal structure of the second coating layer as it is grown out from the first coating layer. During both the cleaning and alloying/coating step, the part platen 154 may be rotated about its axis 156 and oscillated about its center 158 to facilitate uniform coverage of the articles. A thickness measuring gauge 168 is positioned near the part platen 154 in order to monitor the arrival of the evaporated coating material 166 and control formation of the alloyed surface layer and then the thicker coating grown from the alloyed surface layer.
Preferably, the two-step treatment process is carried out sequentially in the same vacuum chamber without releasing the high vacuum to atmospheric pressure between steps. If this occurs a latent oxide layer will form on the cleaned surface and will interfere with the formation of the coating. It is also preferable to accurately control the intensities of the cleaning/augmenting ion beam and the angular position of the articles to be treated relative to this directional beam such that the surface alloyed layer and coating are applied uniformly to the surface to be treated.
Embodiments of the invention are further illustrated by the following non-limiting four Examples in which examples of particular coating parameter and test data associated with the coated items is presented.
Samples of Co—Cr—Mo materials used to manufacture the orthopaedic implants 10 were prepared and coated with a ceramic coating as described herein. The samples were pins and disks utilized in the standard Pin-On-Disk wear test procedure (ASTM F732-00(2006) Standard Test Method for Wear Testing of Polymeric Materials Used in Total Joint Prostheses, American Society For Testing and Materials). The wear of the coated pin and disks was measured and compared to the wear found with uncoated pins and disks manufactured from the same Co—Cr—Mo material.
In this case a two-layer coating was deposited on the pins and disks using the inventive IBED process. The first (inner) layer was titanium nitride (TiN) and the second (outer) layer was aluminum oxide (Al2O3). The procedures and processing parameters utilized to deposit the two-layer coating on the pin and disk sample materials are as follows:
The test conditions and results of the Pin-On-Disk testing are seen in Table V. In this test, the pin and disk sample materials coated with a two layer TiN/Al2O3 coating. As a result of a run for 2,000,000 inches of wear travel in the Pin-On-Disk tester a volumetric loss of 0.25 mm3 is shown. This compares to a volumetric loss of 2.1 mm3 measured for 2,000,000 inches of wear travel for uncoated Co—Cr—Mo material.
A 5 micron thick single layer coating of chromium nitride (Cr2N) was deposited on a 304 stainless steel panel using the inventive process described in U.S. Ser. No. 11/042,150 and then tested for resistance to abrasive wear using a standard Taber Abraser Test. The test was applied using the procedure defined by Military Test Specification (MIL-A-8625F) in which an abrasive wheel (Taber, CS-10), impregnated with 50 micron diameter corundum grits, is rubbed against the coating surface with a loading of 2.2 pounds of force, and run for 10,000 abrasion cycles. The wear loss is measured and presented as the number of microns of coating lost per 10,000 wear cycles.
The procedures and processing parameters utilized to deposit the single layer Cr2N coating on the 304 stainless steel panel are described in Table VI as follows:
The result of the Taber Abrasive Wear Testing is seen in Table VII. The MED Cr2N coating, showed a loss of 0.15 microns (μ) in thickness for the 10,000 cycles of abrasive wear. This compares to a thickness loss of 2.82 microns measured for 10,000 cycles of abrasive wear on uncoated Co—Cr—Mo material with a Rockwell “C” Scale Hardness of 45, that typical of material used for orthopaedic hip and knee implant components.
A 5 micron thick single layer coating of aluminum oxide (Al2O3) was deposited on a 304 stainless steel panel as described herein and then tested for resistance to abrasive wear using a standard Taber Abraser Test. The test was applied using the procedure defined by Military Test Specification (MIL-A-8625F) in which an abrasive wheel (Taber, CS-10), impregnated with 50 micron diameter corundum grits, is rubbed against the coating surface with a loading of 2.2 pounds of force, and run for 10,000 abrasion cycles. The wear loss is measured and presented as the number of microns of coating lost per 10,000 wear cycles.
The procedures and processing parameters utilized to deposit the single layer Al2O3 coating on the 304 stainless steel panel are illustrated in Table VIII as follows:
The result of the Taber Abrasive Wear Testing is seen in Table IX. The IBED Al2O3 coating, showed a loss of 0.07 microns (μ) in thickness for the 10,000 cycles of abrasive wear. This compares to a thickness loss of 2.82 microns measured for 10,000 cycles of abrasive wear on uncoated Co—Cr—Mo material with a Rockwell “C” Scale Hardness of 45, that typical of material used for orthopaedic hip and knee implant components.
Pin and disk samples were prepared from Co—Cr—Mo material used to manufacture orthopaedic implants, and then coated with a ceramic coating as described herein in order to test the fluid retentive properties of the deposited ceramic. In this case a two-layer coating was deposited on the Co—Cr—Mo pin and disk using the inventive MED process. The first (inner) layer was titanium nitride (TiN) and the second (outer) layer was aluminum oxide (Al2O3). The procedures and processing parameters utilized to deposit the two-layer coating on the Co—Cr—Mo pin and disk samples are illustrated in Table X as follows:
An additional set of pin-on-disk samples was prepared from solid, single crystal, alpha phase Al2O3. The counter facing surfaces of this pin-on-disk set would not have the same surface nanostructure, and thus fluid-retentive properties, as would the Al2O3 coating deposited on the Co—Cr—Mo samples using the inventive process.
Both sample pin and disk sets were tested according to the standard pin-on-disk wear test procedure (ASTM F732-00(2006) “Standard Test Method for Wear Testing of Polymeric Materials Used in Total Joint Prostheses, American Society for Testing and Materials”). The samples were immersed in defined bovine calf serum as a lubricant (Hyclone Labs: Cat. No. SH30073.04) during the entirety of the test. After completion of 2,000,000 cycles in the pin-on-disk test, both sample sets were carefully dried and the surface the pins imaged using scanning electron microscopy (SEM), and the surface composition analyzed with energy dispersive X-ray analysis (EDAX).
No residue was detected by either SEM imaging or EDAX analysis on the surface of the single crystal, alpha phase, pin indicating that the surface of the solid Al2O3 pin did not have the properties of a fluid-retentive surface. The IBED-coated Co—Cr—Mo pin surface did however show remnants of a film that had been retained on the surface of the Al2O3 coating.
Conclusions:
The orthopaedic implants 10 with surface treatments provided by this invention will generate less debris in the form of wear products, corrosion products, and metallic ion leaching which are liberated and transported to bone, blood, the lymphatic system, and other internal organs. This will result in less inflammation, toxicity, and immune response resulting in increased longevity of the orthopaedic implant 10 and less adverse effects on the patient. The surface treatments can be applied to a variety of the materials used to fabricate the articulating elements of the modular orthopaedic implants 10, and are useful for a variety of combinations of metal, ceramic, and polyethylene articulating elements.
In addition to orthopedic implants where the inventive process is applied to both mating surfaces of an articulating joint there are other devices which articulate in which it is appropriate to apply the inventive process to only one mating surface. These devices include, and are not be limited to, the knee, the hip, the shoulder, the elbow (ulna), the wrist, the ankle, spine disc, spine facet, the finger, and the toe.
The design of another typical modular articulating orthopaedic implant, for example an artificial shoulder, is shown in
The design of another typical modular articulating orthopaedic implant, for example an elbow, is shown in
The design of another typical modular articulating orthopaedic implant, for example a wrist, is shown in
The design of another typical modular articulating orthopaedic implant, for example an ankle, is shown in
The design of another typical modular articulating orthopaedic implant, for example a facet joint replacement, is shown in
The design of another typical modular articulating orthopaedic implant, for example a lumbar disc replacement, is shown in
The design of another typical modular articulating orthopaedic implant, for example a finger, is shown in
The design of another typical modular articulating orthopaedic implant, for example a toe, is shown in
The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
This application is a Continuation-in-Part of and claims priority to U.S. patent application Ser. No. 12/059,553, now U.S. Pat. No. 9,523,144, filed on Mar. 31, 2008, titled “ORTHOPEDIC IMPLANTS HAVING SELF-LUBRICATED ARTICULATING SURFACES DESIGNED TO REDUCE WEAR, CORROSION AND ION LEACHING,” which claims priority to U.S. patent application Ser. No. 11/042,150, filed on Jan. 26, 2005, now U.S. Pat. No. 7,374,642 issued May 20, 2008, titled “TREATMENT PROCESS FOR IMPROVING THE MECHANICAL, CATALYTIC, CHEMICAL, AND BIOLOGICAL ACTIVITY OF SURFACES, AND ARTICLES TREATED THEREWITH,” which claims priority to U.S. Provisional Application Ser. No. 60/539,996, filed on Jan. 30, 2004, titled “TREATMENT PROCESS FOR IMPROVING THE MECHANICAL, CATALYTIC, CHEMICAL, AND BIOLOGICAL ACTIVITY OF SURFACES, AND ARTICLES TREATED THEREWITH,” the disclosures of which are incorporated herein by reference in their entireties.
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| Number | Date | Country | |
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| 20170258597 A1 | Sep 2017 | US |
| Number | Date | Country | |
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| 60539996 | Jan 2004 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12059553 | Mar 2008 | US |
| Child | 15385061 | US | |
| Parent | 11042150 | Jan 2005 | US |
| Child | 12059553 | US |
