Bioscience IP Limited v Howmedica Osteonics Corp - [2018] APO 40

IP AUSTRALIA
AUSTRALIAN PATENT OFFICE
Bioscience IP Limited v Howmedica Osteonics Corp. [2018] APO 40

Patent Application: 2010202320

Title:Orthopedic paek-on-polymer bearings

Patent Applicant:  Howmedica Osteonics Corp.
Opponent:  Bioscience IP Limited
Delegate:  Dr B. Akhurst
Decision Date:  20 June 2018
Hearing Date:  Written submissions completed on 1 November 2017.

Catchwords: PATENTS - opposition to an amendment – allowability under section 102(1) and 102(2) considered – amendment allowed.

Representation: Patent attorney for the applicant: Phillips Ormonde Fitzpatrick.
Patent attorney for the opponent: Madderns Patent and Trade Mark Attorneys.

IP AUSTRALIA
AUSTRALIAN PATENT OFFICE
Patent Application: 2010202320

Title:Orthopedic paek-on-polymer bearings

Patent Applicant: Howmedica Osteonics Corp.
Date of Decision: 20 June 2018
DECISION
The opposition is unsuccessful.
I allow the amendments.
I award costs according to Schedule 8 against Bioscience IP Limited.
REASONS FOR DECISION
Background

Patent application 2010202320 was filed on 3 June 2010 by Howmedica Osteonics Corp. (the applicant), claiming the priority date 4 June 2009. After examination prompted amendments to the specification, the application was accepted on 11 April 2014 and advertised as such on 8 May 2014.
On 8 August 2014, Thomas Laubenthal filed a notice of opposition to the grant of a patent and the matter was heard on 16 February 2016. In his decision dated 7 April 2016, the hearing officer found claims of the application did not satisfy the requirements for novelty, inventive step and/or clarity, and he allowed the applicant two months in which to file amendments to overcome these defects. The applicant proposed amendments to the specification on 2 June 2016 and, after Thomas Laubenthal commented that the amendments were not allowable under s102, an adverse examination report issued. The applicant responded with submissions after which the request for leave to amend the specification was advertised on 1 December 2016. Thomas Laubenthal did not oppose allowance of the amendments.
Bioscience IP Limited (the opponent) filed a notice of opposition to allowance of the amendments on 31 January 2017, followed by a statement of grounds and particulars on 28 February 2017. Evidence in support, answer and reply to the opposition was completed on 19 May 2017, 19 July 2017 and 21 August 2017, respectively. The matter was heard by way of written submissions filed by the opponent and applicant on 25 October 2017 and 1 November 2017, respectively.
The Law
The request for examination of the patent application was filed on 20 November 2012. As a consequence, the substantive amendments of the Patents Act 1990 (the Act) brought about by the Intellectual Property Laws Amendment (Raising the Bar) Act 2012 on 15 April 2013 do not apply to the present application. Instead, the relevant provisions of the Act in this matter are in section 102 as it existed prior to the introduction of the Raising the Bar Act, which are reproduced below.
(1) An amendment of a complete specification is not allowable if, as a result of the amendment, the specification would claim matter not in substance disclosed in the specification as filed.
(2) An amendment of a complete specification is not allowable after the relevant time if, as a result of the amendment:
(a) a claim of the specification would not in substance fall within the scope of the claims of the specification before amendment; or
(b) the specification would not comply with subsection 40(2) or (3).
The ‘relevant time’ in subsection 102(2) is after the specification has been accepted[1]. Subsections 40(2) and 40(3) of the Act as they apply to the present case are set out below:
(2) A complete specification must:
(a) describe the invention fully, including the best method known to the applicant of performing the invention; and
(b) ….
(3) The claim or claims must be clear and succinct and fairly based on the matter described in the specification.
[1] Subsection 102(2A) of the Act.
Subsection 102(1) requires a comparison between what would be claimed as a result of the proposed amendment and what is disclosed in the specification as filed[2]. When determining whether matter is in substance disclosed the courts have basically applied the test for fair basis. Thus, it is necessary to ask whether the specification as filed provides a “real and reasonably clear disclosure” of the matter in the claims as proposed to be amended.
[2] Bristol-Myers Squibb Company v Apotex Pty Ltd [2010] FCA 814 at [39].
Relevant to s 102(2)(b), the requirement of s 40(3) that a claim is clear will be satisfied if a third party could ascertain, without difficulty, whether or not what he or she proposes to do would fall within the ambit of the claim (Monsanto Co v Commissioner of Patents[3]). A claim does not lack clarity because it uses inexact language or is difficult to construe, as long as it provides a workable standard suitable to the intended use (Minnesota Mining & Manufacturing Co v Beiersdorf (Australia) Ltd[4]). To determine whether a claim is fairly based, the question is whether there is a real and reasonably clear disclosure in the body of the specification of what is then claimed, so that the alleged invention as claimed is broadly, that is to say in a general sense, described in the body of the specification (The High Court in Lockwood Security Products Pty Ltd v Doric Products Pty Ltd[5]).
[3] (1974) 48 ALJR 59 at 60
[4] [1980] HCA 9; (1980) 144 CLR 253 at 274 [46]
[5] [2004] HCA 58; (2004) 217 CLR 274 at [69] in which the High Court approved the words of Gummow J in Rehm Pty Ltd v Websters Security Systems (International) Pty Ltd [1988] FCA 162; (1988) 81 ALR 79 at 95 [54].
The construction of s 102, particularly the effect of the phrase “as a result of the amendment” in ss 102(1) and 102(2), has been conveniently summarised by Moshinsky J in United States Gypsum Company v CSR Building Products Ltd[6]. Relevant to this opposition, the application of s 102(1) and s 102(2) involves a two-stage process. The first step is to identify precisely what is the amendment, by identifying the difference between the accepted specification and the specification as proposed to be amended - the key point to keep in mind is that the words “as a result of the amendment” are not to be confused with the expression “after the amendment” [7]. If by reason of the amendment proposed, and for no other reason, the specification or claims would not comply with the requirements of s 102(1) or s 102(2), the amendment will not be allowable[8].
[6] [2017] FCA 595.
[7] Moshinsky J in United States Gypsum Company v CSR Building Products Ltd [2017] FCA 595 at [34], referring to RGC Mineral Sands Pty Ltd v Wimmera Industrial Minerals Pty Ltd [1998] FCA 1358; (1998) 89 FCR 458 at 466 per Burchett, Carr and Goldburg JJ.
[8] Moshinsky J in United States Gypsum Company v CSR Building Products Ltd [2017] FCA 595 at [35], referring to Bristol-Myers Squibb Co v Apotex Pty Ltd [2010] FCA 814; (2010) 87 IPR 516 at [38] per Yates J.; Bodkin C, Patent Law in Australia (2nd ed, Thomson Reuters, 2014) at [13230].
Subsection 102(3) provides that s 102 does not apply to an amendment for the purpose of correcting a clerical error or obvious mistake made in, or in relation to, a complete specification. The applicant made no submissions relevant to this provision and I will not consider it further.
The opposition
The statement of grounds and particulars identifies the grounds of opposition as non-allowability of the amendments under ss 102(1) and 102(2)(b) of the Act. Each of these grounds was pressed at the hearing.
Specifically, the opponent identified proposed claims 1-3, 6-7 and 11-12 as contravening s 102(1) of the Act, and claims 1, 3 and 6 as contravening s 102(2)(b) with respect to full description (claims 1 and 6) and fair basis (claims 1, 3 and 6).
The evidence in support of the opposition consisted of a declaration by Stephen Trevor O’Brien (O’Brien#1) with exhibits STO-1 to STO-3. Evidence in answer consisted of a declaration by Adrian Crooks (Crooks) with exhibits AC-1 to AC-3. Evidence in reply consisted of a second declaration by Stephen Trevor O’Brien (O’Brien#2) with exhibits STO-4 and STO-5. Each of the declarants gave their evidence in their capacity as the representing Australian patent attorneys[9]. At no stage in their evidence did Mr Crooks or Mr O’Brien suggest that they are themselves persons skilled in the art to which the patent application relates, and I will consider their evidence accordingly.
[9] O’Brien#1 at [1]; Crooks at [1].
The specification and amendments
The specification relates to the use of polyaryl ether ketones (PAEK) on polymer bearing couples in orthopedic prosthetic joints[10]. One such PAEK is polyether ether ketone (PEEK). The inventors had found that PEEK-on-polymer bearing couples have lower wear rates and that they can be manufactured at a lower cost than typical orthopedic bearing couples[11]. The specification was accepted with 14 claims (the accepted claims) which were the subject of the substantive opposition by Thomas Laubenthal. The subsequently proposed amendments to the specification are confined to the claims and reduce their number to 12 - I will refer to these as the proposed claims. The accepted and proposed claims are set out in Annexes A and B to this decision, respectively.
[10] The specification as filed and accepted, at para [0008].
[11] The specification as filed and accepted, at paras [0009]-[0010].
The principles to be applied in construing the claims are well settled in law and were summarised by Bennett J in H Lundbeck A/S v Alphapharm Pty Ltd[12]. Most relevantly, the words in a claim should be read through the eyes of the skilled addressee in the context in which they appear. Words used in a specification, including the claims, are to be given the meaning which the person skilled in the art would attach to them, having regard to his or her own general knowledge and to what is disclosed in the body of the specification. While the claims define the monopoly claimed in the words of the patentee’s choosing, the specification should be read as a whole. It is not permissible to read into a claim an additional integer or limitation to vary or qualify the claim by reference to the body of the specification. However, terms in the claims which are unclear may be defined or clarified by reference to the body of the specification. The construction of a specification, including the claims, is ultimately a question of law for the Court.
[12] [2009] FCAFC 70, 81 IPR 228 [118]-[120].
Proposed independent claims 1 and 6
The most contentious amendments appear in proposed independent claims 1 and 6, which are presented below with deleted text struck-through and new text underlined:
1. An orthopedic prosthetic hip or knee joint comprising:
a first prosthetic bearing component mounted on a femur having a first component bearing surface made completely of a non-carbon fiber reinforced poly ether ketone (PEEK) ~~or a poly aryl ether ketone (PAEK) polymer that is non carbon fiber reinforced~~; and
a second prosthetic bearing component mounted on a proximal tibia or acetabulum having a second component bearing surface made of ultra-high molecular weight polyethylene (UHMWPE) cross-linked by irradiation, the first component and the second component bearing surfaces being in sliding engagement with one another, the PEEK ~~or PAEK~~ polymers having a shore D hardness higher than the UHMWPE cross-linked by irradiation and wherein the PEEK bearing comprises a layer of pure PEEK coated, molded or grafted onto a solid or porous substrate.
76. An orthopedic prosthetic hip or knee joint comprising:
a first hip or knee bearing surface formed of non-fiber reinforced PEEK; and
a second hip or knee bearing surface in sliding contact with the first hip or knee bearing surface, the second bearing surface formed of ultra-high molecular weight polyethylene (UHMWPE) wherein the PEEK bearing comprises a layer of pure PEEK coated, molded or grafted onto a solid or porous substrate.
What is the amendment proposed to claims 1 and 6?
In claim 1, the deletion of the option of a PAEK polymer on the first prosthetic bearing component limits this component to a single embodiment having a bearing surface made completely of a non-carbon fiber reinforced PEEK. This amendment was not contentious at the hearing.
A critical question in this opposition is the effect of introducing into proposed claims 1 and 6 a feature requiring “the PEEK bearing to comprise a layer of pure PEEK coated, molded or grafted onto a solid or porous substrate”. The parties’ disagreed on this point. The opponent considered it to result in the proposed claims contravening ss 102(1) and 102(2)(b). The applicant considered this amendment to narrow the scope of the proposed independent claims from that of the accepted independent claims and on this basis it concluded that no deficiencies arise as a result of this amendment to claims 1 and 6.
Accepted independent claims 1 and 7 each define an orthopedic prosthetic hip or knee joint in terms of the composition of the bearing surface on each of the two bearing components. Neither claim explicitly identifies the nature of the substrate material underlying these bearing surfaces. Turning to the proposed claims, I agree with the parties’ declarants that independent claims 1 and 6 impose no express limitation on the nature of the solid or porous substrate material[13]. Notwithstanding, given the breadth of accepted claims 1 and 7, the explicit limitation in proposed claims 1 and 6 that the pure PEEK layer is coated, molded or grafted to a “solid or porous substrate” must render the scope of the proposed claims either the same as, or narrower than, that of the corresponding accepted claims.
[13] O’Brien#1 [13]; Crooks [23].
Regarding the references in proposed claims 1 and 6 to a layer of ‘pure PEEK’, both the accepted and proposed claims refer to “a first component bearing surface made completely of a non-carbon fibre reinforced poly ether ketone (PEEK)” (emphasis added). This provides the antecedent for the additional reference in the proposed claims to a “pure PEEK” layer on the PEEK bearing substrate.
Do the amendments proposed to claims 1 and 6 result in the specification or claims failing to comply with the requirements of s102?
For the reasons provided above, properly construed, the subject matter encompassed by proposed independent claims 1 and 6 falls wholly within the scope of accepted claims 1 and 7, respectively. Consistent with this conclusion, the opponent has not opposed these claims under s 102(2)(a).
The opponent submitted that as a result of the amendment, proposed claims 1 and 6 fail to comply with subsections 102(1), and 102(2)(b) as it relates to s 40(2) sufficiency and s 40(3) fair basis. Specifically, the opponent submitted that there is no disclosure in the specification of “a layer of pure PEEK coated, molded, or grafted onto a solid or porous substrate” of any material type. Relevant to s 40(2), the opponent submitted that the specification does not identify with any clarity how to coat, mold or graft a layer of pure PEEK onto a solid or porous substrate of any material type.
The additional feature now explicitly present in proposed claims 1 and 6, that the PEEK bearing comprises a layer of pure PEEK applied in the specified manner to “a solid or porous substrate”, falls wholly within the scope of the accepted independent claims. If I accept the opponent’s argument that the claim as amended would claim matter not in substance disclosed in the specification as filed (section 102(1)), then this does not arise as a result of the amendment. Such a deficiency would have been present in the claims before amendment. Similarly, if the opponent is correct in their assertion that there is a lack of sufficiency and/or a lack of fair basis (section 102(2)(b)), then this also does not arise as a result of the amendment.
I find that proposed claims 1 and 6 comply with ss 102(1) and 102(2).
Proposed dependent claims 2, 7 , 11, 12
What is the amendment?
Although the words of dependent claims 2 and 12 are unchanged in the proposed claim set, the scope of these claims includes the features of proposed claim 1 to which they are appended. Proposed claim 2 specifies the nature of the cross-linked UHMWPE polymer identified in claim 1. Proposed claim 12 restricts the orthopedic prosthetic joint according to claim 1 to being “substantially as described herein with reference to the accompanying figures”.
Consequential amendments make proposed claims 7 and 11 dependent on proposed claim 6, otherwise the wording of these claims is identical to that of corresponding accepted claims 8 and 13.
Do the amendments result in the specification or claims failing to comply with the requirements of s102?
Any change in the scope of claims 2, 7, 11 or 12 is wholly dependent on the amendment proposed to claim 1 or claim 6. Given my findings above with respect to proposed claims 1 and 6, I conclude that proposed claims 2, 7, 11 and 12 are wholly within the scope of the corresponding accepted claims. Consistent with this conclusion and what I have said above, the opponent has not opposed these claims under s102(2)(a).
I have found above that the amendments proposed to claims 1 and 6 comply with ss 102(1) 102(2). It logically follows that the amendments proposed to claims 2, 7, 11 and 12 could not result in the specification contravening the allowability criteria in ss 102(1) or 102(2).
Proposed dependent claim 3
What is the amendment to claim 3?
Claim 3 in the accepted and proposed claims are identically worded as follows:
3.The orthopedic prosthetic joint as set forth in claim 1 wherein the PEEK bearing is a stand-alone component.
Claim 3 incorporates the features of proposed claim 1 to which it is appended. I accept the opponent’s submission that claim 3 defines an orthopedic prosthetic joint having all of the features (a)-(c) below, since this is explicit in the terms of claim 3 read together with proposed claim 1:
(a)   a first prosthetic bearing component having a bearing surface made completely of a non-carbon fiber reinforced poly ether ketone (PEEK);
(b)   the PEEK bearing comprises a layer of pure PEEK coated, molded or grafted onto a solid or porous substrate; and
(c)   the PEEK bearing is a stand-alone component.
For completeness, claim 3 also explicitly requires the prosthetic joint to comprise:
(d) a second prosthetic bearing component having a bearing surface of cross-linked UHMWPE.
In construing the term “stand-alone component” in claim 3, the parties’ declarants referred to the evidence of Jenny Elizabeth Burke, an expert witness in the substantive opposition, who construed it as follows:
“that the first prosthetic bearing component is a separate component of the orthopaedic prosthetic hip or knee joint made from bulk material” [14].
[14] Crooks at [30] & O’Brien#2 at [24], both declarants refer to an extract of the evidence of Jenny Elizabeth Burke dated 6 February 2015, in Annexure AC-2 to the Crooks declaration.
The opponent’s declarant concluded that the stand-alone PEEK bearing in claim 3 is an alternative embodiment to that identified in proposed claim 1, and accordingly he construed claim 1 as identifying a PEEK bearing comprising a PEEK layer on a solid or porous substrate material other than PEEK. The applicant’s declarant concluded that Ms Burke’s construction “does not appear to in any way preclude an embodiment in which a PEEK layer is coated, molded or grafted onto a solid or porous substrate of a relevant material”[15].
[15] Crooks at [28].
Recently, in Meat & Livestock Australia Limited v Cargill, Inc[16], Justice Beach stated:
“… a claim is to be construed from the perspective of how a person skilled in the art would have understood the patentee to be using the words, informed by the notional skilled addressee’s relevant general knowledge and what has been disclosed in the specification. But to consider such a perspective does not entail that the Court necessarily requires expert evidence to assist on construction. If it is clear that the claims are to be read according to their ordinary meaning with no special meaning given to any word or phrase, if the science or technical issues are easily comprehensible and if, more generally, the Court does not require expert assistance in understanding the context of the claims, then expert evidence on construction may not only be unnecessary, but unhelpful and distracting.”
[16] [2018] FCA 51 at [218].

I believe this principle is applicable in this case. Claim 3 requires the PEEK bearing to be a stand-alone component and consequently it defines what the PEEK bearing is, not what it is made of. Therefore, while I accept Ms Burke’s evidence that the PEEK bearing is a separate component of the orthopedic prosthetic hip or knee joint, I do not accept that claim 3 necessarily requires it to be made of bulk material.
Do the amendments result in the specification or claims failing to comply with the requirements of s102?
In accepted and proposed claim 1, both the first and second prosthetic bearing components are separate components of the prosthetic joint. Therefore, in the proposed claim set, claim 3 adds little to claim 1. Accordingly, I find the amendment to claim 3 does not result in the specification claiming matter not in substance disclosed in the specification as filed.
Even if I am wrong on this point, I have been able to construe claim 3 and give it a meaning, and as a consequence I am satisfied that it provides a workable standard suitable to the intended use in that the skilled addressee could determine what would fall within the scope of the claim. Therefore, proposed claim 3 is clear. Furthermore, the body of the specification at para [0008], provides a real and reasonably clear disclosure of the PEEK bearing of claim 3 as I have construed it and consequently claim 3 is fairly based.
Proposed dependent claims 4, 5 and 8-10
What is the amendment?
In the proposed claim set, claims 4 and 5 are each dependent on claim 1, and claims 8-10 are dependent on claim 6. Reflecting the amendments proposed to the independent claims, proposed claims 4, 5 and 8-10 omit the reference to “the PEEK bearing comprising a layer of pure PEEK coated, molded or grafted onto a solid or porous substrate”. As they did prior to the amendment, these claims specify the nature of the solid or porous substrate in the claims to which they are appended. The amendments proposed to these claims were not contentious at the hearing and I will not consider them further.
Conclusion
The opposition fails on all grounds. It follows that the amendment request should be allowed.
Costs
Both parties claimed costs in the opposition. Ordinarily in proceedings such as these, costs follow the event, and I see no reason to vary the usual practice. Costs according to Schedule 8 should be awarded against the opponent Bioscience IP Limited.
B. Akhurst
Delegate of the Commissioner of Patents
ANNEX A: The accepted claims
1.An orthopedic prosthetic hip or knee joint comprising:
a first prosthetic bearing component mounted on a femur having a first component bearing surface made completely of a non-carbon fiber reinforced poly ether ketone (PEEK) or a poly aryl ether ketone (PAEK) polymer that is non-carbon fiber reinforced; and
a second prosthetic bearing component mounted on a proximal tibia or acetabulum having a second component bearing surface made of ultra-high molecular weight polyethylene (UHMWPE) cross-linked by irradiation, the first component and the second component bearing surfaces being in sliding engagement with one another, the PEEK or PAEK polymers having a shore D hardness higher than the UHMWPE cross- linked by irradiation.
2. The orthopedic prosthetic joint as set forth in claim 1 wherein the UHMWPE polymer may be mono-polymer, co-polymer, polymer with surface grafting or coating.
3. The orthopedic prosthetic joint as set forth in claim 1 wherein the PEEK bearing is a stand-alone component.
4. The orthopedic prosthetic joint as set forth in claim 1 wherein the PEEK bearing comprises a layer of pure PEEK coated, molded or grafted onto a solid or porous polymer substrate.
5. The orthopedic prosthetic joint as set forth in claim 1 wherein the PEEK bearing comprises layer of pure PEEK coated, molded or grafted onto a solid or porous ceramic substrate.
6. The orthopedic prosthetic joint as set forth in claim 1 wherein a bone contacting surface comprises a porous PEEK layer for bone ingrowth.
7. An orthopedic prosthetic hip or knee joint comprising:
a first hip or knee bearing surface formed of non-fiber reinforced PEEK; and
a second hip or knee bearing surface in sliding contact with the first hip or knee bearing surface, the second bearing surface formed of ultra-high molecular weight polyethylene (UHMWPE)
8. The orthopedic implant as set forth in claim 7, wherein the UHMWPE is cross-linked at least three times by irradiation, heating after irradiation and cooling after each heating.
9. The orthopedic prosthetic joint as set forth in claim 7 wherein the PEEK bearing comprises a layer of pure PEEK coated, molded or grafted onto a solid or porous polymer composite substrate.
10. The orthopedic prosthetic joint as set forth in claim 7 wherein the PEEK bearing comprises a layer pure PEEK coated, molded or grafted onto a solid or porous metallic substrate.
11. The orthopedic prosthetic joint as set forth in claim 7 wherein the PEEK bearing comprises a layer of pure PEEK coated, molded or grafted onto a solid or porous ceramic or ceramic composite substrate.
12. The orthopedic prosthetic joint as set forth in claim 7 wherein a bone contacting surface has a porous PEEK layer for bone ingrowth.
13. The orthopedic prosthetic joint as set forth in claim 7 wherein the polyethylene has been cross-linked by irradiation.
14. An orthopedic prosthetic joint according to claim 1, substantially as described herein with reference to the accompanying figures.
ANNEX B: The proposed claims
1. An orthopedic prosthetic hip or knee joint comprising:
a first prosthetic bearing component mounted on a femur having a first component bearing surface made completely of a non-carbon fiber reinforced poly ether ketone (PEEK); and
a second prosthetic bearing component mounted on a proximal tibia or acetabulum having a second component bearing surface made of ultra-high molecular weight polyethylene (UHMWPE) cross-linked by irradiation, the first component and the second component bearing surfaces being in sliding engagement with one another, the PEEK polymers having a shore D hardness higher than the UHMWPE cross-linked by irradiation and wherein the PEEK bearing comprises a layer of pure PEEK coated, molded or grafted onto a solid or porous substrate.
2. The orthopedic prosthetic joint as set forth in claim 1 wherein the UHMWPE polymer may be mono-polymer, co-polymer, polymer with surface grafting or coating.
3.The orthopedic prosthetic joint as set forth in claim 1 wherein the PEEK bearing is a stand-alone component.
4. The orthopedic prosthetic joint as set forth in claim 1 wherein the solid or porous substrate is a polymer substrate.
5. The orthopedic prosthetic joint as set forth in claim 1 wherein the solid or porous substrate is a ceramic substrate.
6. An orthopedic prosthetic hip or knee joint comprising:
a first hip or knee bearing surface formed of non-fiber reinforced PEEK; and
a second hip or knee bearing surface in sliding contact with the first hip or knee bearing surface, the second bearing surface formed of ultra-high molecular weight polyethylene (UHMWPE) wherein the PEEK bearing comprises a layer of pure PEEK coated, molded or grafted onto a solid or porous substrate.
7. The orthopedic implant as set forth in claim 6, wherein the UHMWPE is cross-linked at least three times by irradiation, heating after irradiation and cooling after each heating.
8. The orthopedic prosthetic joint as set forth in claim 6 wherein the solid or porous substrate is a polymer composite substrate.
9. The orthopedic prosthetic joint as set forth in claim 6 wherein the solid or porous substrate is a metallic substrate.
10. The orthopedic prosthetic joint as set forth in claim 6 wherein the solid or porous substrate is a ceramic or ceramic composite substrate.
11. The orthopedic prosthetic joint as set forth in claim 6 wherein the polyethylene has been cross-linked by irradiation.
12. An orthopedic prosthetic joint according to claim 1, substantially as described herein with reference to the accompanying figures.