(19)
(11)EP 3 359 208 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
05.01.2022 Bulletin 2022/01

(21)Application number: 16784677.3

(22)Date of filing:  07.10.2016
(51)International Patent Classification (IPC): 
A61L 27/12(2006.01)
A61L 27/46(2006.01)
A61L 27/42(2006.01)
A61L 27/56(2006.01)
(52)Cooperative Patent Classification (CPC):
A61L 27/46; A61L 2400/06; A61L 27/427; A61L 27/12; A61L 2400/08; A61L 27/56; A61L 2430/02; A61L 27/422; A61L 2430/24
 
C-Sets:
  1. A61L 27/46, C08L 5/04;
  2. A61L 27/46, C08L 1/28;

(86)International application number:
PCT/US2016/055940
(87)International publication number:
WO 2017/062737 (13.04.2017 Gazette  2017/15)

(54)

CURABLE CALCIUM PHOSPHATE COMPOSITIONS FOR USE WITH POROUS STRUCTURES AND METHODS OF USING THE SAME

HÄRTBARE CALCIUMPHOSPHATZUSAMMENSETZUNGEN ZUR VERWENDUNG MIT PORÖSEN STRUKTUREN UND VERFAHREN ZUR VERWENDUNG DAVON

COMPOSITIONS DE PHOSPHATE DE CALCIUM DURCISSABLES DESTINÉES À ÊTRE UTILISÉES AVEC DES STRUCTURES POREUSES, ET LEURS PROCÉDÉS D'UTILISATION


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 08.10.2015 US 201562238776 P

(43)Date of publication of application:
15.08.2018 Bulletin 2018/33

(73)Proprietor: Zimmer Knee Creations, Inc.
Exton, PA 19341 (US)

(72)Inventors:
  • ANGLE, Siddhesh
    Allston, Massachusetts 02134 (US)
  • STRUNK, Michael
    Exton, Pennsylvania 19341 (US)
  • CHANG, Tak Lung
    Exton, Pennsylvania 19341 (US)
  • COALE, Bradford J.
    Chester, New Jersey 07930 (US)
  • STEBBINS, Greg
    Hoboken, New Jersey 07030 (US)
  • LIEPINS, Imants
    Asbury, New Jersey 08802 (US)

(74)Representative: Mays, Julie et al
Venner Shipley LLP 200 Aldersgate
London, EC1A 4HD
London, EC1A 4HD (GB)


(56)References cited: : 
WO-A1-2013/106323
WO-A2-2009/097412
US-A1- 2007 128 245
WO-A2-2005/117919
US-A1- 2006 088 601
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    BACKGROUND



    [0001] Healthy trabecular or cancellous human bone has interconnected pores in the range of 100-600 microns in diameter and has a compressive strength of nominally 0.5-10 MPa. The structure of trabecular bone has an important role in the tolerance of skeletal tissue to mechanical stresses. Typical methods for implantation of orthopedic devices that mimic the biomechanical properties of trabecular bone leave regions of the remaining host bone not contacted to or interfaced with the orthopedic device, decreasing the security and rigidity with which the implant is seated in the remaining host bone, slowing healing and osteo-incorporation into the implant, and increasing the likelihood of revision surgery. WO2013/106323 discloses orthopaedic implants having an open porous metal portion and a bone cement portion for filling voids in bones.

    SUMMARY OF THE INVENTION



    [0002] The present invention provides an orthopedic implant or device comprising a porous metal structure comprising:

    a porous substrate comprising a plurality of ligaments that define pores of the porous substrate, and a biocompatible metal coating on the plurality of ligaments of the porous substrate;

    a curable calcium phosphate composition or a cured product thereof at least partially in contact with the porous metal structure, the curable calcium phosphate composition comprising:calcium phosphate, a perfusion modifier, and a physiologically acceptable fluid, wherein the perfusion modifier comprises 0.5 wt% to 10 wt% of the curable calcium phosphate composition, and wherein the perfusion modifier is sodium alginate and/or a cellulose selected from methylcellulose, carboxymethylcellulose, hydroxypropylmetylcellulose, hydroxyethylcellulose, a salt thereof, or a combination thereof.



    [0003] The present invention also provides a method of forming the claimed orthopedic implant or device, the method comprising injection-perfusing the curable calcium phosphate composition into the porous metal structure, to form the claimed orthopedic implant or device. In some embodiments, the biocompatible metal coating can include tantalum metal.

    [0004] Various embodiments of the present invention provide certain advantages over other compositions, apparatuses, and methods of using the same, at least some of which are unexpected. For example, in various embodiments, the orthopedic implant or device can provide increased contact between the host bone and an orthopedic implant. In some embodiments, by providing increased contact between the host bone and the implant, the orthopedic implant or device can provide a more rigid and secure connection between the host bone and the implant (e.g., decreasing the chance of implant loosening). In some embodiments, by providing increased contact between the host bone and the implant, the orthopedic implant or device can provide increased healing speed, increased speed of osteo-incorporation into the implant, and increased extent of osteo-incorporation into the implant. In some embodiments, by providing increased contact between the host bone and the implant, the orthopedic implant or device can provide a decreased chance that revision surgery will be needed, or can increase the time span between implantation and revision surgery.

    [0005] In various embodiments, the curable calcium phosphate composition can be a reactive precursor to a bone-remodelable solid (e.g., the cured product of the curable calcium phosphate composition). As used herein, "bone-remodelable" refers to a process including resorption of the material (e.g., removal) followed by ossification (e.g., new bone formation). In various embodiments, the cured product of the curable calcium phosphate composition can be more bone-remodelable than other compositions, such as other bone substitute materials, remodeling more quickly, more completely, or a combination thereof. In various embodiments (e.g., prior to hydration), the curable calcium phosphate composition can provide a stable intermediate for production of a reactive precursor to a bone-remodelable solid. In various embodiments, the stable intermediate can be more stable, can be stored for longer periods, or a combination thereof, as compared to other compositions for forming bone-remodelable solids. In various embodiments, the curable calcium phosphate composition can provide more controlled and predictable crystallization kinetics (e.g., to form the cured product of the composition) than other compositions. In various embodiments, the curable composition can provide reduced or no phase separation between reactive solids and carrier fluid during use. In various embodiments, the curable composition can provide reduced or no phase separation or premature crystallization of the cured product of the composition during use, as compared to other compositions that form bone-remodelable materials.

    [0006] In various embodiments, the curable calcium phosphate composition can enhance the biomechanical properties and eventual integration of a porous structure into bone. In various embodiments, the curable calcium phosphate composition can be used in contact with a porous structure to increase integration of new bone with porous surfaces of the porous structure. In various embodiments, the cured product of the curable calcium phosphate composition can provide a bone-remodelable conductive scaffold for integration of new bone with the surface of the porous structure. In various embodiments, the cured product of the curable calcium phosphate composition can form an uninterrupted or less interrupted conductive interface with the surrounding host bone and augment the porous structure. In various embodiments, the curable calcium phosphate composition can have a flowability and viscosity that is suitable for injecting not only around a porous structure but also at least partially within the porous structure (e.g., perfused within). In various embodiments, the curable calcium phosphate composition can at least partially be used inside the porous structure, causing increased speed and extent of bone interdigitation within the porous structure during the recovery process.

    [0007] The method of using the curable calcium phosphate composition, the cured product thereof, or the method of using or forming the apparatus including the porous structure and the curable composition or a cured product not falling within the scope of the claimed subject-matter, can be compatible with minimally invasive surgical techniques. In various embodiments, the curable calcium phosphate composition can accelerate osseous integration, such as of the porous structure, such as via osteoconductivity of the cured product thereof. The curable calcium phosphate composition can be conveniently injected with nominal digital (i.e., finger) pressure, but is not covered by the claims. In various embodiments, augmentation of implants with the curable calcium phosphate composition can enhance bone ingrowth and end-to-end fusion (e.g., with an ankle fusion implant).

    BRIEF DESCRIPTION OF THE FIGURES



    [0008] The drawings are not necessarily drawn to scale. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.

    FIG. 1 illustrates an implanted apparatus including a curable calcium phosphate composition and a porous structure, in accordance with various embodiments.

    FIGS. 2A-B illustrate an implanted apparatus including a curable calcium phosphate composition and a porous structure, in accordance with various embodiments.

    FIG. 3 illustrates an implanted apparatus including a curable calcium phosphate composition and a porous structure, in accordance with various embodiments.

    FIG. 4 illustrates an implanted apparatus including a curable calcium phosphate composition and a porous structure, in accordance with various embodiments.

    FIGS. 5A-D illustrate various views of a porous metal block, in accordance with various embodiments.

    FIG. 6 illustrates an extrusion testing set up, in accordance with various embodiments.

    FIGS. 7A-B illustrate penetration of a bone substitute material through a porous metal block, in accordance with various embodiments.


    DETAILED DESCRIPTION OF THE INVENTION



    [0009] The term "about" as used herein can allow for a degree of variability in a value or range, for example, within 10%, within 5%, or within 1% of a stated value or of a stated limit of a range, and includes the exact stated value or range.

    [0010] The term "substantially" as used herein refers to a majority of, or mostly, as in at least about 50%, 60%, 70%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or at least about 99.999% or more, or 100%.

    [0011] As used herein, the term "polymer" refers to a molecule having at least one repeating unit and can include copolymers.

    [0012] In various embodiments, salts having a positively charged counterion can include any suitable positively charged counterion. For example, the counterion can be ammonium(NH4+), or an alkali metal such as sodium (Na+), potassium (K+), or lithium (Li+). In some embodiments, the counterion can have a positive charge greater than +1, which can in some embodiments complex to multiple ionized groups, such as Zn2+, Al3+, or alkaline earth metals such as Ca2+ or Mg2+.

    [0013] In various embodiments, salts having a negatively charged counterion can include any suitable negatively charged counterion. For example, the counterion can be a halide, such as fluoride, chloride, iodide, or bromide. In other examples, the counterion can be nitrate, hydrogen sulfate, dihydrogen phosphate, bicarbonate, nitrite, perchlorate, iodate, chlorate, bromate, chlorite, hypochlorite, hypobromite, cyanide, amide, cyanate, hydroxide, permanganate. The counterion can be a conjugate base of any carboxylic acid, such as acetate or formate. In some embodiments, a counterion can have a negative charge greater than -1, which can in some embodiments complex to multiple ionized groups, such as oxide, sulfide, nitride, arsenate, phosphate, arsenite, hydrogen phosphate, sulfate, thiosulfate, sulfite, carbonate, chromate, dichromate, peroxide, or oxalate.

    [0014] The polymers described herein can terminate in any suitable way. In some embodiments, the polymers can terminate with an end group that is independently chosen from a suitable polymerization initiator, -H, -OH, a substituted or unsubstituted (C1-C20)hydrocarbyl (e.g., (C1-C10)alkyl or (C6-C20)aryl) interrupted with 0, 1, 2, or 3 groups independently selected from -O-, substituted or unsubstituted -NH-, and -S-, a poly(substituted or unsubstituted (Ci-C20)hydrocarbyloxy), and a poly(substituted or unsubstituted (C1-C20)hydrocarbylamino). Curable calcium phosphate composition, or cured product thereof.

    [0015] The present invention provides a curable calcium phosphate composition. The curable calcium phosphate composition includes calcium phosphate and a perfusion modifier. The curable calcium phosphate composition, in an unhydrated state, can be in the form of a powder, such as a flowable powder. In a hydrated state, the curable calcium phosphate composition can be in the form of a flowable paste or putty having a consistency and viscosity that is suitable for perfusion into and around a porous structure, and that can be suitable for injection through a needle. In a hydrated state, the curable calcium phosphate composition can be moldable and cohesive when applied to an implant site in vivo. The curable calcium phosphate composition, in a hydrated state, can cure (e.g., harden) to form a cured product of the curable calcium phosphate composition. The curable calcium phosphate composition can be self-curable, such that in a hydrated state, the composition cures to form a solid material without using any curing accelerators and without exposing the curable composition to particular conditions for curing.

    [0016] The cured product can have a different composition than the curable calcium phosphate composition (e.g., during curing, reaction products of the curable composition can form that are different than the components of the curable composition). The cured product of the calcium phosphate composition can approximate the chemical composition of natural bone. The cured product of the calcium phosphate composition can include calcium phosphate (e.g., any one or more materials that qualify as a calcium phosphate, and not necessarily the same one or more materials that were present in the curable composition). The cured product of the calcium phosphate composition can be suitable as a bone-substitute material, can be used to repair bone (e.g., damaged bone), can be bone-remodelable, and can be sufficiently strong and rigid to provide structural support to the surrounding regions of a host bone. The cured product of the calcium phosphate composition can be used as a delivery vehicle for biologically active materials (e.g., wherein the biologically active materials can be present in the curable composition, or can be added to the cured product after formation thereof). The cured product of the calcium phosphate composition can be formed outside a patient and then implanted, or the curable composition can be implanted in a patient and then allowed to cure in vivo.

    [0017] The curable calcium phosphate composition can be in an unhydrated state (e.g., a powder) or a hydrated state (e.g., a paste). When the curable calcium phosphate is in a hydrated state, at least some aqueous fluid is present in the curable calcium phosphate composition, such as water or saline. The amount of fluid in the composition can be adjusted to provide a desired consistency of the hydrated curable calcium phosphate composition (e.g., more or less viscous). The aqueous fluid can be about 0.001 wt% to about 99.999 wt% of the composition, about 30 wt% to about 60 wt%, about 40 wt% to about 50 wt%, or about 0.001 wt% or less, or less than, equal to, or more than 0.01 wt%, 0.1, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 32, 34, 36, 38, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 52, 54, 56, 58, 60, 65, 70, 75, 80, 82, 84, 86, 88, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 99.9, 99.99 wt%, or about 99.999 wt% or more. The aqueous fluid is a physiologically acceptable fluid. The physiologically acceptable fluid can include or can be water, saline, phosphate buffer, biological fluid, or a combination thereof. The biological fluid can include or can be blood (e.g., whole blood, warm or cold blood, and stored or fresh blood; treated blood, such as blood diluted with at least one physiological solution, including but not limited to saline, nutrient, or anticoagulant solutions, or a combination thereof), a blood component (e.g., platelet concentrate (PC), apheresed platelets, platelet-rich plasma (PRP), platelet-poor plasma (PPP), platelet-free plasma, plasma, serum, fresh frozen plasma (FFP), components obtained from plasma, packed red cells (PRC), buffy coat (BC), or a combination thereof), a blood product (e.g., blood products derived from blood or derived from bone marrow), milk, urine, saliva, seminal fluid, vaginal fluid, synovial fluid, lymph fluid, amniotic fluid, the fluid within a yolk sac of an egg, chorion of an egg, allantois of an egg, sweat, tears, or a combination thereof.

    [0018] The calcium phosphate can be any one or more minerals that include at least one calcium ion (Ca2+) and a phosphate, such as an orthophosphate (PO43-), metaphosphate (PO31-), a pyrophosphate (P2O74-). The calcium phosphate can include a hydrogen or hydroxide ion. The calcium phosphate can include one calcium phosphate mineral or more than one calcium phosphate mineral. The calcium phosphate (e.g., the one or more calcium phosphate minerals) can form any suitable proportion of the curable calcium phosphate composition, such as about 0.001 wt% to about 99.999 wt% of the composition, about 40 wt% to about 99.999 wt%, about 40 wt% to about 70 wt%, or about 40 wt% to about 60 wt%, or about 0.001 wt% or less, or less than, equal to, or more than about 0.01 wt%, 0.1, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 32, 34, 36, 38, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 62, 64, 66, 68, 70, 75, 80, 82, 84, 86, 88, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 99.9, 99.99 wt%, or about 99.999 wt% or more. The calcium phosphate can include amorphous calcium phosphate, poorly crystalline calcium phosphate, hydroxyapatite, carbonated apatite (e.g., calcium-deficient hydroxyapatite), monocalcium phosphate, calcium metaphosphate, heptacalcium phosphate, dicalcium phosphate dihydrate, tetracalcium phosphate, octacalcium phosphate, calcium pyrophosphate, tricalcium phosphate, or a combination thereof. As used herein and applied to a calcium phosphate, the term "amorphous" means a calcium phosphate having no or only short range crystallographic order, e.g., crystallographic order over less than 100 nm. The calcium phosphate can include amorphous calcium phosphate and a second calcium phosphate including poorly crystalline calcium phosphate, hydroxyapatite, carbonated apatite (e.g., calcium-deficient hydroxyapatite), monocalcium phosphate, calcium metaphosphate, heptacalcium phosphate, dicalcium phosphate dihydrate, tetracalcium phosphate, octacalcium phosphate, calcium pyrophosphate, tricalcium phosphate, or a combination thereof. The calcium phosphate can include or can be a combination of amorphous calcium phosphate and dicalcium phosphate dihydrate, wherein the mass ratio of the amorphous calcium phosphate to the dicalcium phosphate dihydrate can be about 99:1 or more, or less than, equal to, or more than 19:1, 9:1, 8:1, 7:1, 6:1, 5:1, 4:1, 3:1, 2:1, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:19, or about 1:99 or less.

    [0019] The perfusion modifier is sodium alginate and/or a cellulose selected from methylcellulose, carboxymethylcellulose, hydroxypropylmethylcellulose, hydroxyethylcellulose, a salt therof, or a combination therof. The perfusion modifier improves the ability of the calcium phosphate composition to infiltrate the porous network of a porous structure (e.g., at least the parts of the porous network at and near the surface of the porous structure), such as a porous network similar to a trabecular network of cancellous bone. The perfusion modifier (e.g., the one or more perfusion modifier compounds) comprises 0.5 wt% to 10 wt%, of the curable calcium phosphate composition. The perfusion modifier can be a lyophilized perfusion modifier, wherein one or more compounds in the perfusion modifier are lyophilized. For example, the perfusion modifier can be a calcium carboxymethylcellulose sponge or fibers lyophilized from a dilute basic aqueous solution of a calcium salt and sodium carboxymethylcellulose. Calcium ions can be exchanged and sequestered as a carboxylate salt, available to precipitate in solution with phosphates, available to quench anticoagulants such as ACD-A, or available to initiate platelet activation and clotting. Thus, the curable composition can include a lyophilized perfusion modifier stabilized by sequestration of ionic elements and ligands.

    [0020] In some embodiments, the curable calcium phosphate composition includes a biologically active modifier. In some embodiments, the curable calcium phosphate composition is free of biologically active modifiers. The curable calcium phosphate composition can include one biologically active modifier or multiple biologically active modifiers. The one or more biologically active modifiers can form any suitable proportion of the curable calcium phosphate composition, such as about 0.001 wt% to about 40 wt% of the composition, about 0.001 wt% to about 10 wt%, or about 0.001 wt% or less, or less than, equal to, or more than about 0.01 wt%, 0.1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, or about 40 wt% or more of the composition. The biologically activate modifier can be at least one of an antibody, an antibiotic, a polynucleotide, a polypeptide, a protein (e.g., an osteogenic protein, such as BMP-2, BMP-3, BMP-3b, BMP-4, BMP-5, BMP-6, BMP-7, BMP-8, BMP-9, BMP-10, BMP-11, BMP-12, BMP-13, BMP-14, BMP-15, BMP-16, BMP-17, BMP-18, or a combination thereof), an anti-cancer modifier, a growth factor, a vaccine, or a combination thereof. Anti-cancer modifiers can include alkylating modifiers, platinum modifiers, antimetabolites, topoisomerase inhibitors, antitumor antibiotics, antimitotic modifiers, aromatase inhibitors, thymidylate synthase inhibitors, DNA antagonists, farnesyltransferase inhibitors, pump inhibitors, histone acetyltransferase inhibitors, metalloproteinase inhibitors, ribonucleoside reductase inhibitors, TNF alpha agonists, TNF alpha antagonists, endothelin A receptor antagonists, retinoic acid receptor agonists, immuno-modulators, hormonal modifiers, antihormonal modifiers, photodynamic modifiers, and tyrosine kinase inhibitors.

    [0021] In various embodiments, the curable calcium phosphate composition includes a binder. In some embodiments, the curable calcium phosphate composition is free of binders. The curable calcium phosphate composition can include one binder or more than one binder. The one or more binders can form any suitable proportion of the curable calcium phosphate composition, such as about 0.001 wt% to about 20 wt% of the composition, about 0.001 wt% to about 5 wt%, or about 0.001 wt% or less, or less than, equal to, or more than about 0.01 wt%, 0.1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18 wt%, or about 20 wt% or more. The binder can be at least one of a) a polysaccharide, a nucleic acid, a carbohydrate, a protein, a polypeptide, a poly(α-hydroxy acids), a poly(lactone), a poly(amino acid), a poly(anhydride), a poly(orthoester), a poly(anhydride-co-imide), a poly(orthocarbonate), a poly(α-hydroxy alkanoate), a poly(dioxanone), a poly(phosphoester), poly(L-lactide) (PLLA), poly(D,L-lactide) (PDLLA), polyglycolide (PGA), poly(lactide-co-glycolide (PLGA), poly(L-lactide-co-D, L-lactide), poly(D,L-lactide-co-trimethylene carbonate), polyhydroxybutyrate (PHB), poly(ε-caprolactone), poly(δ-valerolactone), poly(y-butyrolactone), poly(caprolactone), polyacrylic acid, polycarboxylic acid, poly(allylamine hydrochloride), poly(diallyldimethylammonium chloride), poly(ethyleneimine), polypropylene fumarate, polyvinyl alcohol, polyvinylpyrrolidone, a polyethylene, polymethylmethacrylate, a carbon fiber, poly(ethylene glycol), poly(ethylene oxide), poly(vinyl alcohol), poly(vinylpyrrolidone), poly(ethyloxazoline), a poly(ethylene oxide)-co-poly(propylene oxide) block copolymer, poly(ethylene terephthalate)polyamide, and copolymers thereof; b) a homo- or co-polymer having one or more monomers selected from the group consisting of acrolein potassium, (meth)acrylamides, (meth)acrylic acid and salts thereof, (meth)acrylates, acrylonitrile, ethylene, ethylene glycol, ethyleneimine, ethyleneoxide, styrene sulfonate, vinyl acetate, vinyl alcohol, vinyl chloride, and vinylpyrrolidone); c) a polyphenol complexing agent selected from a gallotannin, a ellagitannin, a taragallotannin, a caffetannin, a proanthocyanidin, catechin, epicatechin, chlorogenic acid, and arbutin; and d) an agent selected from alginic acid, arabic gum, guar gum, xanthan gum, gelatin, chitin, chitosan, chitosan acetate, chitosan lactate, chondroitin sulfate, N,O- carboxymethyl chitosan, a dextran (e.g., α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, or sodium dextran sulfate), fibrin glue, glycerol, hyaluronic acid, sodium hyaluronate, a cellulose (e.g., methylcellulose, carboxymethylcellulose, hydroxypropylmethylcellulose, hydroxyethylcellulose, a salt thereof, or a combination thereof), a glucosamine, a proteoglycan, a starch, lactic acid, a poly(ethylene oxide-co-propylene oxide), sodium glycerophosphate, collagen, glycogen, a keratin, and silk.

    [0022] In various embodiments, the curable calcium phosphate composition includes an effervescent agent. In some embodiments, the curable calcium phosphate composition is free of an effervescent agent. The curable calcium phosphate composition can include one effervescent agent or multiple effervescent agents. The one or more effervescent agents can form any suitable proportion of the curable calcium phosphate composition, such as about 0.001 wt% to about 40 wt% of the composition, or about 0.001 wt% or less, or less than, equal to, or more than about 0.01 wt%, 0.1, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, or about 40 wt% or more. In some embodiments, the effervescent agent includes a combination of at least two compounds. The effervescent agent can include a carbonate compound and a bicarbonate compound which can react to form CO2 gas upon hydration (or soon thereafter) of said composition. The carbonate and bicarbonate compounds can have a molar ratio of about 1:1 to about 1:9, or about 1:1 or less, or less than, equal to, or more than about 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, or about 1:9 or more. The carbonate and bicarbonate compounds can have any suitable counterion (e.g., the compounds can be sodium carbonate and sodium bicarbonate). The formed CO2 gas can form pores in the hardened material, such as pores having a size of about 1 micron to about 1000 microns, or about 10 microns to about 100 microns. The porosity of a cured product of the curable composition not including any effervescent compound can be about 0. The porosity of a cured product of the curable composition that includes an effervescent compound can be about 5% to about 60%, or 5% or less, or less than, equal to, or more than about 10%, 15, 20, 25, 30, 35, 40, 45, 50, 55%, or about 60% or more. In some embodiments, the effervescent agent produces a substantially continuous matrix of interconnected pores in the cured product of the curable calcium phosphate composition.

    [0023] In some embodiments, the curable calcium phosphate composition includes demineralized bone. The curable calcium phosphate composition can include any suitable proportion of demineralized bone, such as about 0.001 wt% to about 40 wt% of the composition, or about 0.001 wt% or less, or less than, equal to, or more than about 0.01 wt%, 0.1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38 wt%, or about 40 wt% or more. The demineralized bone can include or can be demineralized bone fibers.

    [0024] Also described herein, but not according to the invention, is the use of the curable calcium phosphate composition or a cured product thereof for treatment of a joint disorder or condition.

    Orthopedic implants or devices including a porous structure.



    [0025] The present invention provides an orthopedic implant or device as defined by the claims. Any suitable proportion of the porous structure can be contacted with the curable calcium phosphate composition. For example, about 0.001% to about 100% of the outer surface of the porous structure can be in contact with the curable calcium phosphate composition or a cured product thereof, or about 0.001% or less, or less than, equal to, or more than about 0.01%, 0.1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 82, 84, 86, 88, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 99.9, 99.99, or about 99.999% or more. In some embodiments, the inner volume (e.g., pore space) of the porous structure can include the curable calcium phosphate composition or a cured product thereof, wherein 0% or about 0.001% to about 100% of the outer surface of the porous structure is in contact with the curable calcium phosphate composition or a cured product thereof. Any suitable amount of the pore space of the porous structure can be filled with the curable calcium phosphate composition or a cured product thereof, such as 0%, or such as about 0.001% or less, or less than, equal to, or more than about 0.01%, 0.1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 82, 84, 86, 88, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 99.9, 99.99, or about 99.999%. The curable calcium phosphate composition or cured product thereof can extend into the pore space of the porous structure to any suitable depth from the surface, such as equal to, less than, or more than about 1 mm, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or about 100 mm or more. In some embodiments, the curable calcium phosphate composition can extend throughout the pore space of the porous structure.

    [0026] The porous structure can include any suitable material. In various embodiments, the porous structure includes a linear olefin polymer or copolymer, an acrylonitrile butadiene styrene (ABS) polymer, an acrylic polymer, a celluloid polymer, a cellulose acetate polymer, a cyclic olegin copolymer (COC), an ethylene-vinyl acetate (EVA) polymer, an ethylene vinyl alcohol (EVOH) polymer, an ethylene n-butyl acetate polymer (EnBA), a fluoroplastic, an ionomer, an acrylic/PVC alloy, a liquid crystal polymer (LCP), a polyacetal polymer (POM or acetal), a polyacrylate polymer, a polymethylmethacrylate polymer (PMMA), a polyacrylonitrile polymer (PAN or acrylonitrile), a polyamide polymer (PA or nylon), a polyamide-imide polymer (PAI), a polyaryletherketone polymer (PAEK), a polybutadiene polymer (PBD), a polybutylene polymer (PB), a polybutylene terephthalate polymer (PBT), a polycaprolactone polymer (PCL), a polychlorotrifluoroethylene polymer (PCTFE), a polytetrafluoroethylene polymer (PTFE), a polyethylene terephthalate polymer (PET), a polycyclohexylene dimethylene terephthalate polymer (PCT), a polycarbonate polymer (PC), a polyhydroxyalkanoate polymer (PHA), a polyketone polymer (PK), a polyester polymer, a polyethylene polymer (PE), a polyetheretherketone polymer (PEEK), a polyetherketoneketone polymer (PEKK), a polyetherketone polymer (PEK), a polyetherimide polymer (PEI), a polyethersulfone polymer (PES), a polyethylenechlorinate polymer (PEC), a polyimide polymer (PI), a polylactic acid polymer (PLA), a polymethylpentene polymer (PMP), a polyphenylene oxide polymer (PPO), a polyphenylene sulfide polymer (PPS), a polyphthalamide polymer (PPA), a polypropylene polymer, a polystyrene polymer (PS), a polysulfone polymer (PSU), a polytrimethylene terephthalate polymer (PTT), a polyurethane polymer (PU), a polyvinyl acetate polymer (PVA), a polyvinyl chloride polymer (PVC), a polyvinylidene chloride polymer (PVDC), a polyamideimide polymer (PAI), a polyarylate polymer, a polyoxymethylene polymer (POM), a styrene-acrylonitrile polymer (SAN), or a combination thereof. The linear olefin polymer or copolymer can be ultra high molecular weight polyethylene (UHMWPE), high-density polyethylene (HDPE), cross-linked polyethylene (PEX or XLPE), medium density polyethylene (MDPE), linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), very low-density polyethylene (VLDPE), a copolymer thereof, or a combination thereof. The linear olefin polymer or copolymer can be a polymer or copolymer of at least one of propene, butene, pentene, heptene, hexene, octene, nonene, decene, ethylene, a (C1-C10)alkylenoic acid, a vinyl (C1-C10)alkanoate ester, and a (C1-C10)alkyl(C1-C10)alkylenoate ester. Any one of more materials in this paragraph can independently form any suitable proportion of the porous structure, such as 0%, such as about 0.001 wt% to about 99 wt%, or about 0.001 wt% to about 50 wt%, or about 0.001 wt% or less, or equal to or less than about 0.01 wt%, 0.1, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, 99.9, 99.99 wt%, or about 99.999 wt% or more.

    [0027] The one or more materials in the porous structure includes a plurality of ligaments. The plurality of ligaments define the pores of the porous structure. The open spaces between the ligaments form a matrix of continuous channels having few or no dead ends, such that growth of soft tissue and/or bone through the porous structure is substantially uninhibited. The porous structure can be suited for contacting bone, soft tissue, or a combination thereof, and in this regard, can be useful as bone substitutes and other implants and implant components that are receptive to cell and tissue ingrowth, for example, by allowing bony tissue or other tissue to grow into the porous structure over time to enhance fixation (e.g., osseointegration) between the structure and surrounding bodily structures.

    [0028] The porous structure is an orthopedic implant, such as an orthopedic implant for implantation in a hip, knee, ankle, shoulder, spine, jaw, or elbow. The porous structure can include or can be a prosthetic acetabular component, a prosthetic proximal femoral component, a prosthetic distal femoral component, a prosthetic tibial component, a prosthetic humeral component, a prosthetic dental component, a prosthetic spinal component, or a combination thereof. The porous structure can include or can be an acetabular cup, a tibial cone, a glenoid implant, or a distal tibia-tallus fusion body.

    Porous metal structure.



    [0029] The porous structure is a porous metal structure. The porous metal structure can be any suitable proportion of the porous structure, such as about 0.001 wt% to about 100 wt%, or about 50 wt% to about 100 wt%, or about 0.001 wt% or less, or less than, equal to, or greater than about 0.01 wt%, 0.1, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 82, 84, 86, 88, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 99.9, 99.99, or about 99.999 wt% or more.

    [0030] The porous metal structure can include any suitable metal. The metal can be a biocompatible metal. The metal can be tantalum, titanium, niobium, hafnium, tungsten, an alloy thereof (e.g., a tantalum alloy, a titanium alloy, a niobium alloy, a hafnium alloy, a tungsten alloy, a tantalum niobium alloy), or a combination thereof. The porous metal structure can include tantalum metal.

    [0031] The porous metal structure includes a porous substrate including a plurality of ligaments. The plurality of ligaments define the pores of the porous substrate and of the porous metal structure. The porous metal structure includes a biocompatible metal coating on (e.g., applied to) the plurality of ligaments of the porous substrate.

    [0032] The porous substrate can have a lower density than the biocompatible metal thereon. The porous substrate can include or can be a foam having a lower density than the biocompatible metal thereon. The porous substrate can include or can be reticulated vitreous carbon foam. For example, the reticulated vitreous carbon (RVC) foam can have a plurality of vitreous carbon ligaments that define dodecahedron (12-sided) pores therebetween. RVC foam is commercially available in porosities ranging from 10 to 200 pores per cubic inch (i.e., about 0.61 to about 12 pores per cubic cm), and more specifically in porosities of 65, 80, and 100 pores per cubic inch (i.e., about 3.97, 4.88, or about 6.10 pores per cubic cm, respectively). Such RVC foam substrates may be formed by pyrolyzing an open-cell, polymer foam.

    [0033] The biocompatible metal on the porous substrate can be any suitable biocompatible metal. The biocompatible metal can include a Group IV-VI refractory metal. The biocompatible metal can be tantalum, titanium, niobium, hafnium, tungsten, an alloy thereof (e.g., a tantalum alloy, a titanium alloy, a niobium alloy, a hafnium alloy, a tungsten alloy, a tantalum niobium alloy), or a combination thereof. The biocompatible metal can be tantalum. The biocompatible metal can be deposited on the porous substrate, such as via chemical vapor deposition. The biocompatible metal can cover any suitable amount of the surface area of the porous substrate (e.g., including the outer surface and the inner surfaces that form the pores), such as about 10% to about 100%, or about 90% to about 100%, or about 10% or less, or less than, equal to, or more than about 15%, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 99.9, 99.99, or about 99.999% or more.

    [0034] The porous metal structure can be suited for contacting bone, soft tissue, or a combination thereof, and in this regard, can be useful as bone substitutes and other implants and implant components that are receptive to cell and tissue ingrowth, for example, by allowing bony tissue or other tissue to grow into the porous structure over time to enhance fixation (e.g., osseointegration) between the structure and surrounding bodily structures. Such structures can provide lightweight, yet strong porous implants. Certain porous metal structures, despite having such high porosities, are capable of withstanding extreme mechanical loads at the time of implantation and over long periods of time (for example, where a highly porous, three-dimensional metallic structure is forcefully impacted and press fit into a bone, by itself or connected to another implant, and maintains its shape during impaction and following many months or years of service in the body). Such structures can be manufactured according to any suitable technique or process. An example of a porous metal structure is produced using Trabecular Metal Technology available from Zimmer, Inc., of Warsaw, Indiana. Trabecular Metal is a trademark of Zimmer, Inc. Such a material may be formed from a reticulated vitreous carbon foam substrate which is infiltrated and coated with a biocompatible metal, such as tantalum, by a chemical vapor deposition ("CVD") process in the manner disclosed in detail in U.S. Patent No. 5,282,861 and in Levine, B.R., et al., "Experimental and Clinical Performance of Porous Tantalum in Orthopedic Surgery," Biomaterials 27 (2006) 4671-4681.

    [0035] In some instances, the porous metal structure can be a highly porous, three-dimensional metallic structure that is fabricated using a selective laser sintering (SLS) or other additive manufacturing-type process such as direct metal laser sintering or electron beam melting. In one example, a three-dimensional (3-D) porous article is produced in layer-wise fashion from a laser-fusible powder (e.g., a single-component metal powder), which is deposited one layer at a time. The powder is fused, remelted or sintered, by the application of laser energy that is directed to portions of the powder layer corresponding to a cross section of the article. After the fusing of the powder in each layer, an additional layer of powder is deposited, and a further fusing step is carried out, with fused portions or lateral layers fusing so as to fuse portions of previous laid layers until a three-dimensional article is complete. In certain embodiments, a laser selectively fuses powdered material by scanning cross-sections generated from a 3-D digital description of the article (e.g., from a CAD file or scan data) on the surface of a powder bed. Complex geometries can be created using such techniques, and in some instances, net shape and near net shape implants are constructed. In some embodiments, a non-porous or essentially non-porous base substrate will provide a foundation upon which a three-dimensional porous structure will be built and fused thereto using a SLS or other additive manufacturing-type process. Such substrates can incorporate one or more of a variety of biocompatible metals such as any of those disclosed herein.

    [0036] Generally, the porous metal structure includes a large plurality of ligaments that define open voids (e.g., pores) or channels between the ligaments. The open spaces between the ligaments form a matrix of continuous channels having few or no dead ends, such that growth of soft tissue and/or bone through the open porous metal is substantially uninhibited. According to some aspects of the present disclosure, exterior surfaces of an open porous metal structure can feature terminating ends of the above-described ligaments. Such terminating ends can be referred to as struts, and they can generate a high coefficient of friction along an exposed porous metal surface. Such features can impart an enhanced affixation ability to an exposed porous metal surface for adhering to bone and soft tissue. Also, when such highly porous metal structures are coupled to an underlying substrate, a small percentage of the substrate may be in direct contact with the ligaments of the highly porous structure; for example, approximately 15%, 20%, or 25%, of the surface area of the substrate may be in direct contact with the ligaments of the highly porous structure.

    [0037] The porous metal structure can be fabricated such that it includes a variety of densities in order to selectively tailor the structure for particular orthopedic applications (for example, by matching the structure to surrounding natural tissue in order to provide an improved matrix for tissue ingrowth and mineralization). Such structures can be isotropic or anisotropic. In this regard, according to certain embodiments, an open porous metal structure may be fabricated to have a substantially uniform porosity, density, void (pore) size, pore shape, and/or pore orientation throughout, or to have one or more features such as porosity, density, void (pore) size, pore shape, and/or pore orientation being varied within the structure, or within a portion thereof. For example, a porous metal structure may have a different pore size, pore shape, and/or porosity at different regions, layers, and surfaces of the structure. The ability to selectively tailor the structural properties of the open porous metal enables, for example, tailoring of the structure for distributing stress loads throughout the surrounding tissue and promoting tissue growth into and within the open porous metal. In some instances, a highly porous, three-dimensional metallic structure, once formed, will be infiltrated and coated with one or more coating materials such as biocompatible metals such as any of those disclosed herein.

    [0038] The porous metal structure can have any suitable relative density, wherein the relative density of the porous metal structure is a percentage obtained by dividing an actual density of the porous metal structure (e.g., of the porous metal structure alone, without the curable calcium phosphate composition or cured product thereof therein) by a theoretical density of the biocompatible metal of the coating. The relative density can be about 12% to about 50%, or about 12% or less, or less than, equal to, or more than about 13%, 14, 15, 16, 17, 18, 19, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or about 50% or more.

    [0039] The porous metal structure can have any suitable specific compressive strength. For example, the porous metal structure (e.g., the porous metal structure alone, without the curable calcium phosphate composition or cured product thereof therein) can have a specific compressive strength of about 50 MPa to about 2,000 MPa, or about 200,000 psi, or about 100 MPa to about 500 MPa, or about 50 MPa or less, or less than, equal to, or more than about 60 MPa, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 165 (i.e., about 24,000 psi), 170, 175, 180, 185, 190, 195, 200, 225, 250, 275, 300, 350, 400, 450, 500, 600, 700, 800, 900, 1,000, 1,250, 1,500, 1,750, 2,000, 5,000, 10,000, 20,000, 50,000, 100,000, 150,000, or about 200,000 psi or more.

    Method of forming the orthopedic implant or device.



    [0040] The present invention provides a method of forming the orthopedic implant or device as claimed, the method comprising injection-perfusing the curable calcium phosphate composition into the porous metal structure, to form the claimed orthopedic implant or device.

    [0041] Also described herein, but not falling within the scope of the claimed subject-matter is that the method can be performed in vivo, such as including some steps in vivo (with other steps outside the body) or all steps performed in vivo. The method can include or can be a primary or revision surgery, such as of a hip implant, a leg implant, a shoulder implant, a jaw implant, a spine implant, or an ankle implant. The method can include treatment of osteolytic lesions (e.g., by implanting the curable composition, cured product thereof, porous structure, or any combination thereof, in contact therewith). The method can be a surgical method, such as wherein the curable calcium phosphate composition is placed in contact with the porous structure in vivo, or wherein the curable calcium phosphate composition is placed in contact with the porous structure outside the body and the apparatus is then implanted. The curable calcium phosphate composition can be allowed to cure before implantation or afterwards.

    [0042] Also described herin, but not falling within the scope of the claimed subject-matter, is a method that can include a primary implantation surgery or revision surgery for an acetabular cup implant, as illustrated in FIG. 1. The acetabular cup 100 can include a porous structure with a porosity similar to trabecular bone on the side that contacts the pelvis 105, and a smooth surface on the side that contacts the proximal femur 120 (not shown). The acetabular cup 100 can be used with cannulated fenestrated screws 115 to anchor the cup to the pelvis 105. The curable calcium phosphate composition 110 is placed in regions that facilitate augmentation of screw fixation. The curable calcium phosphate composition 110 is placed in regions that augment fixation of the acetabular cup 100 to the acetabulum of the pelvis 105. At least some of the curable calcium phosphate composition 110 penetrates the pores of the porous structure of the acetabular cup 100. The curable calcium phosphate composition 110 can reduce or eliminate loosening of the implanted cup due to poor quality of bone in the acetabulum. The curable calcium phosphate composition 110 can create a continuous osteoconductive region between the porous structure and the acetabulum.

    [0043] Also described herein, but not falling within the scope of the claimed subject-matter, is a method that can include a primary implantation surgery or revision surgery for a tibial cone implant, as illustrated in FIGS. 2A-B. FIG. 2A shows an end-on cutaway view of a proximal tibia 200 having a tibial cone implant 205 therein, wherein the tibial cone implant 205 is a porous structure. FIG. 2B shows a side cutaway view of the tibia 200 having the tibial cone implant 205 therein. The implant includes the curable calcium phosphate composition 210 between the porous structure 205 and the bone of the tibia 200. The tibial cone implant 205 has a porosity similar to trabecular bone. The curable calcium phosphate material at least partially penetrates the porous structure of the tibial cone implant 205. The curable calcium phosphate material 210 is placed in regions of the tibia to augment the fixation of the cone implant 205 and eliminate mismatch between the endosteal contour of the tibial metaphysis that accepts the tibial cone implant 205. The curable calcium phosphate material 210 reduces or eliminates loosening of the implanted tibial cone implant 205 due to poor quality of bone in the proximal tibia 200. The curable calcium phosphate material 210 creates a continuous osteoconductive region between the tibial cone implant 205 and the tibia 200.

    [0044] Also described herein, but not falling within the scope of the claimed subject-matter, is a method that can include a primary implantation surgery or revision surgery for a glenoid implant, as illustrated in FIG. 3. The scapula 300 includes a glenoid pegged implant 305 which includes the porous structure 306 and a smooth articulating surface 307. The implant includes the curable calcium phosphate composition 310 between the porous structure 306 and the bone 300. The porous structure 306 has a porosity similar to trabecular bone. The curable calcium phosphate composition 310 provides structural fixation of the pegged components of the implant 305 within the scapula 300 to augment fixation therein. The curable calcium phosphate composition 310 at least partially penetrates into the pores of the porous structure 306. The curable calcium phosphate composition 310 improves the seating of the implant 305 by filling out small spaces between the bone 300 and the implant 305, such as may result from irregularities after reaming. The fixation of pegged glenoid implant 305 has better chances of integrating if the holes are filled with an osteoconductive material. The curable calcium phosphate material 310 is a flowable material that can be delivered with a syringe or can be a moldable material which can be inserted with pure finger pressure. The curable calcium phosphate material 310 can reduce or eliminate loosening of the implant 305 due to poor quality of bone in the scapula 300 or due to gaps between the scapula 300 and the implant 305. The curable calcium phosphate material 310 can create a continuous osteoconductive region between the implant 305 and the bone 300.

    [0045] Also described herein, but not falling within the scope of the claimed subject-matter, is a method that can include a primary implantation surgery or revision surgery for a total ankle replacement spacer, as illustrated in FIG. 4. The distal tibia 400 and the talus 405 include tibiotalar porous fusion implant 410, which is a porous structure having porosity similar to trabecular bone. A curable calcium phosphate composition 415 is inside the implant 410 and is between the ends of the implant 410 and the distal tibia 400 and the talus 405. The curable calcium phosphate composition 415 can be placed in the implant 410 prior to implantation or the implant 410 can be filled with the composition 415 after implantation using a port or delivery hole in the implant 410 (not shown). The curable calcium phosphate composition 415 augments the fixation of the implant 410, and eliminates mismatch between the contour of the distal tibia 400 and the implant 410, such as resulting from irregularities after reaming distal tibia 400. The curable calcium phosphate composition 415 reduces or eliminates loosening of the implant 410 due to poor quality of bone in the fusion mass. The curable calcium phosphate composition 415 creates a continuous osteoconductive region between the implant 410 and the tibia 400 and talus 405. The curable calcium phosphate composition 415 can be inductive or conductive to facilitate formation of a fusion mass (not shown).

    Examples


    Part I.


    Example 1-1.



    [0046] A low density lyophilized calcium carboxymethylcellulose is mixed in the dry state with a reactive calcium deficient (Ca:P ratio of less than 1.67) calcium phosphate (an amorphized 1:1 mixture by mass of amorphous calcium phosphate and dicalcium phosphate dihydrate), forming a mixture that is about 5.5 wt% calcium carboxymethylcellulose and about 94.5 wt% amorphous calcium phosphate. The dry powder mixture is then mixed with deionized water, forming a mixture that is 45 wt% deionized water. A flowable paste results which, upon dissociation of Ca2+ ions, hardens into a crystalline solid. The flowable paste perfuses porous trabecular structures without phase separation of the calcium phosphate from the aqueous cellulose derivative.

    Example 1-2.



    [0047] Sodium alginate is mixed in solution with a 1:1 by weight mixture of reactive amorphous calcium phosphate and a calcium deficient carbonate apatite (having a Ca:P molar ratio of less than 1.67 with CO32- ions occupying both A (OH- substitutions) and B (PO43- substitutions) sites in the apatite lattice), forming a mixture that has a weight ratio of sodium alginate to the mixture of reactive amorphous calcium phosphate and the calcium deficient carbonate apatite of 5.5:94.5. The mixture is lyophilized. The dry powder is then mixed with deionized water to form a mixture that is 45 wt% deionized water. A flowable paste results which, upon dissociation of Ca2+ ions from the carbonate apatite, hardens into a crystalline solid. The flowable paste perfuses porous trabecular structures without phase separation of the calcium phosphate from the aqueous sodium alginate.

    Example 1-3.



    [0048] Sodium carboxymethylcellulose is lyophilized with CaCO3 and mixed in the dry state with a reactive calcium deficient amorphous calcium phosphate (an amorphized 1:1 mixture by mass of amorphous calcium phosphate and dicalcium phosphate dihydrate) with a sodium carboxymethylcellulose to reactive calcium deficient amorphous calcium phosphate weight ratio of 5.5:94.5. The dry powder is then mixed with autologous blood to form a mixture that is 45 wt% autologous blood. A flowable paste results which, upon dissociation of Ca2+ and metal carbonate ions, hardens into a crystalline carbonate apatite solid. The flowable paste perfuses porous trabecular structures without phase separation of the calcium phosphate from the aqueous cellulose derivative.

    Part II.



    [0049] This Part compares the injectability and performance of various calcium phosphate bone substitute materials (BSMs) that were injected into a porous metal Trabecular Metal (TMT) block (1.614 in x 1.732 in). Performance characteristics included measurement of forces required to extrude the BSM into the TMT block in addition to qualitative assessment and gross histology. Mixing of BSMs was performed in PMDS (precision mixing and delivery system, P/N: 31-0001). For the purpose of this testing all materials were gamma irradiated at (25-35) KGy.

    [0050] Materials. The following materials were used in this Part: Physiological saline (0.9% NaCl, VWR®); 1 cc Medallion® syringes (P/N: 30-1098); Texture Technologies TA-HD plus (Stable Micro Systems); TMT blocks (1.614 in x 1.732 in); 24 x 14 cc PMDS (P/N: 31-0001); 4 funnels for MedMix AG (P/N: 30-1124); 6 Internal pin (P/N: 30-1125); 6 x 7.5 g Sample #2 powder in MedMix AG syringes (PMDS); and 6 x 5 cc Sample #1 powder in MedMix AG syringes (PMDS). Sample #1 was 100% CaP3. Sample #2 was 91.5% CaP3, 5 wt% EfferSoda® (a mixture of 10 wt% sodium carbonate and 90 wt% sodium bicarbonate), and 3.5 wt% carboxymethylcellulose. The CaP3 was a 1:1 (by weight) mixture of ball-milled amorphous calcium phosphate and dicalcium phosphate dehydrate. The ball-milling was performed using a 10 mm diameter high-density ZrO2 ball for 3 hours. The amorphous calcium phosphate was prepared using a low temperature double decomposition technique, by adding rapidly a calcium solution (0.36 M), to phosphate solution (0.16 M) in a basic (pH~13) media. The amorphous phase was then stabilized using three crystal growth inhibitor ions (CO32-, Mg2+, and P2O74-), freeze-dried, and heated (450 °C, 1 h) to remove additional moisture and some crystal growth inhibitors. The dicalcium phosphate dehydrate also prepared using wet chemistry by adding rapidly a calcium solution (0.30 M), to phosphate solution (0.15 M) in a slightly acidic (pH~5-6) media. During precipitation, the chemical composition of the dicalcium phosphate dehydrate was controlled to approximately 10 to 25% (w/w) apatite. The dicalcium phosphate dehydrate wet cake was then vacuum dried (6 h at 37 °C), and milled to achieve a particle size of less than 125 µm.

    [0051] Testing facilities. The testing facilities and the services provided by each test facility are described in Table 1.
    Table 1: Test facilities.
    Test facilityAddressTest method
    Isomedix 435 Whitney Street Northborough, MA 01532 Phone#(508)393-9323 Gamma Irradiation at 25-35 kGy
    Zimmer Biomet Etex 38 Sidney St. Cambridge, MA 02139 Extrusion (Injectability)
    Zimmer Biomet TMT Parsippany, NJ Sectioning and gross histology


    [0052] TMT blocks. FIGS. 5A-D illustrates the dimensions of the TMT block, which had a void in the middle. FIG. 5A illustrates a top view of the TMT block. FIG. 5B illustrates a cut-away view of the TMT block taken along line A-A from FIG. 5A. FIG. 5C illustrates a side view of the TMT block. FIG. 5D illustrates a cut-away view of the TMT block taken along line B-B from FIG. 5D.

    Example 2-1. Testing of Samples.



    [0053] All testing was conducted using sterile Samples. Each ETEX product was tested according to the schedule outlined in Table 2.
    Table 2. Testing schedule.
    Type of CannulaTest MethodNumber of BlocksMaterial
    11G Cannula Extrusion Force (Maximum and Average) 3 Sample #1
    11G Cannula Extrusion Force (Maximum and Average) 4 Sample #2


    [0054] Samples were hydrated with 0.9% sodium chloride USP saline according to the appropriate L/P ratio per each product (Sample 1 = 0.5 mL/g, Sample 2 = 0.4 mL/g) and mixed in MedMix AG syringes for approximately 60 seconds to achieve a paste with a smooth consistency. The BSM Samples were tested to measure injection force through an 8G cannula for EquivaBone and through an 11G cannula for all other products. The 1 cc Medallion® syringes (P/N: 30-1098) were attached with the 8G and 11G cannulas into the hole (0.020 in) of the TMT blocks. Each Sample paste was extruded into a TMT block from a 1 cc syringe, and the maximum filling force required to make the extrusion was measured. The extrusion testing set-up is illustrated in FIG. 6.

    Example 2-2. Results.



    [0055] The raw data is given in Table 3. A summary of the results is given in Table 4.

    [0056] Injection of Sample #1 into the TMT block showed forces higher than the accepted standard of 10 kgf. This was due to a complete fill of the simulated void and inability of the material to intrude the porous structure any further. On the contrary, the Sample #2 material consistently showed injection forces significantly lower than the accepted standard, even after the void was filled. One block was tested with 10 cc of Sample #2 and it continued to show lower injection forces in spite of the excess material injected into the block.
    Table 3. Raw data.
    SampleSize1 cc syringe #TMT block #L/P (mL/g)Mean force (kg)Maximum injection force (kg)Comments
    1-1 5 cc 1 1 0.5 0.071 0.30 Injected through 11 G cannula
    2 0.21 0.72
    3 0.31 1.60
    4 0.554 2.71
    5 3.388 9.83 Hard to plunge paste by hand due to phase
    1-2 5 cc 1 2 0.5 0.047 0.10 Injected through 11 G cannula
    2 0.221 1.10
    3 0.296 1.03
    4 3.517 22.62
    5 n/a n/a Hard to plunge paste by hand due to phase
    1-3 5 cc 1 3 0.5 0.053 0.42 Injected through 11 G cannula
    2 0.072 0.42
    3 0.198 0.71
    4 0.366 1.06
    5 3.309 12.67 Easy to plunge
    2-1 5 cc 1 4 0.5 1.62 2.57 Injected through 11 G cannula
    2 2.945 3.76
    3 2.529 3.36
    4 3.132 4.01
    5 2.733 3.61 Easy to plunge
    2-2 5 cc 1 5 0.4 1.721 2.92 Injected through 11 G cannula
    2 2.695 3.47
    3 2.774 3.76
    4 2.702 3.78
    5 2.688 3.7
    6 0.706 3.1 Only plunged by instrument (Texture)
    2-3 5 cc 1 6 0.4 1.73 3.05 Injected through 11 G cannula
    2 1.852 2.54
    3 2.473 3.30
    4 2.903 3.95
    5 3.221 4.24
    6 0.681 5.69 Only plunged by instrument (Texture)
    2-4 10 cc 1 7 0.4 2.481 4.195 Injected through 11 G cannula. On syringe #9, paste was injected but after 9 cc the paste came out from the block.
    2 3.342 4.504
    3 3.406 4.560
    4 3.479 4.635
    5 4.034 5.357
    6 4.409 5.809
    7 4.34 6.110
    8 4.733 7.513
    9 3.783 5.485
    10 6.932 8.846 Only plunged by instrument (Texture)
    Table 4. Summary of results.
    BSMSeqMean Force (kgf)Maximum Force (kgf)Comments
    Sample #1 5 cc N=3 1 0.06 ± 0.01 0.28 ± 0.16  
    2 0.17 ± 0.08 0.74 ± 0.34  
    3 0.27 ± 0.06 1.11 ± 0.45  
    4 1.48 ± 1.77 8.80 ± 12.00 High maximum force due to complete defect fill and limited intrusion.
    5 3.35 ± 0.06 11.25 ± 2.01 High maximum force due to complete defect fill and limited intrusion.
    Sample #2 5 cc N=3 1 1.67 ± 0.07 2.87 ± 0.27  
    2 2.46 ± 0.64 3.43 ± 0.35  
    3 2.39 ± 0.48 3.22 ± 0.62  
    4 2.77 ± 0.33 3.70 ± 0.37  
    5 2.77 ± 0.11 3.75 ± 0.17  
    Sample #2 10 cc N=1 1 2.48 4.20  
    2 3.34 4.50  
    3 3.45 4.56  
    4 3.48 4.64  
    5 4.03 5.36  
    6 4.41 5.81  
    7 4.34 6.11  
    8 4.73 7.51  
    9 3.78 5.49  
    10 6.93 8.85  


    [0057] FIGS. 7A-B illustrate photographs of Sample #2 after infusion thereof through into the TMT block. The TMT block was cut in order to better show the Sample in the block. The block sections showed penetration of Sample #2 through porous TMT block. The material showed intrusion and inter-digitation with the metal surrounding the void at the center of the TMT block.

    Example 2-3. Analysis.



    [0058] Sample #2 showed qualitative intrusion into the porous TMT block. The injection forces for Sample #2 were also below the accepted standard of 10 kgf, the approximate capability of an average human hand. In comparison, injection forces for Sample #1 were higher due to limited intrusion.


    Claims

    1. An orthopedic implant or device comprising:

    a porous metal structure comprising:

    a porous substrate comprising a plurality of ligaments that define pores of the porous substrate; and

    a biocompatible metal coating on the plurality of ligaments of the porous substrate;

    a curable calcium phosphate composition or a cured product thereof at least partially in contact with the porous metal structure, the curable calcium phosphate composition comprising:

    calcium phosphate;

    a perfusion modifier; and

    a physiologically acceptable fluid,

    wherein the perfusion modifier comprises 0.5 wt% to 10 wt% of the curable calcium phosphate composition, and

    wherein the perfusion modifier is sodium alginate and/or a cellulose selected from methylcellulose, carboxymethylcellulose, hydroxypropylmethylcellulose, hydroxyethyl cellulose, a salt thereof, or a combination thereof.


     
    2. The orthopedic implant or device of claim 1, wherein the porous metal structure comprises a linear olefin polymer or copolymer, an acrylonitrile butadiene styrene (ABS) polymer, an acrylic polymer, a celluloid polymer, a cellulose acetate polymer, a cyclic olegin copolymer (COC), an ethylene-vinyl acetate (EVA) polymer, an ethylene vinyl alcohol (EVOH) polymer, an ethylene n-butyl acetate polymer (EnBA), a fluoroplastic, an ionomer, an acrylic/PVC alloy, a liquid crystal polymer (LCP), a polyacetal polymer (POM or acetal), a polyacrylate polymer, a polymethylmethacrylate polymer (PMMA), a polyacrylonitrile polymer (PAN or acrylonitrile), a polyamide polymer (PA or nylon), a polyamide-imide polymer (PAI), a polyaryletherketone polymer (PAEK), a polybutadiene polymer (PBD), a polybutylene polymer (PB), a polybutylene terephthalate polymer (PBT), a polycaprolactone polymer (PCL), a polychlorotrifluoroethylene polymer (PCTFE), a polytetrafluoroethylene polymer (PTFE), a polyethylene terephthalate polymer (PET), a polycyclohexylene dimethylene terephthalate polymer (PCT), a polycarbonate polymer (PC), a polyhydroxyalkanoate polymer (PHA), a polyketone polymer (PK), a polyester polymer, a polyethylene polymer (PE), a polyetheretherketone polymer (PEEK), a polyetherketoneketone polymer (PEKK), a polyetherketone polymer (PEK), a polyetherimide polymer (PEI), a polyethersulfone polymer (PES), a polyethylenechlorinate polymer (PEC), a polyimide polymer (PI), a polylactic acid polymer (PLA), a polymethylpentene polymer (PMP), a polyphenylene oxide polymer (PPO), a polyphenylene sulfide polymer (PPS), a polyphthalamide polymer (PPA), a polypropylene polymer, a polystyrene polymer (PS), a polysulfone polymer (PSU), a polytrimethylene terephthalate polymer (PTT), a polyurethane polymer (PU), a polyvinyl acetate polymer (PVA), a polyvinyl chloride polymer (PVC), a polyvinylidene chloride polymer (PVDC), a polyamideimide polymer (PAI), a polyarylate polymer, a polyoxymethylene polymer (POM), a styrene-acrylonitrile polymer (SAN), or a combination thereof.
     
    3. The orthopedic implant or device of either of claims 1 or 2, wherein the porous metal structure comprises at least one of tantalum, titanium, niobium, hafnium, tungsten, an alloy thereof, or a combination thereof.
     
    4. The orthopedic implant or device of any one of claims 1-3, wherein the porous substrate comprises a foam having lower density than the biocompatible metal coating thereon.
     
    5. The orthopedic implant or device of any one of claims 1-4, wherein the relative density of the porous metal structure is 12% to 50%, the relative density being a percentage obtained by dividing an actual density of the porous metal structure by a theoretical density of the biocompatible metal of the coating.
     
    6. The orthopedic implant or device of any one of claims 1-5, wherein the specific compressive strength of the porous metal structure is at least 165.5 MPa.
     
    7. The orthopedic implant or device of any one of claims 1-6, wherein the cured product of the curable calcium phosphate composition is at least partially in contact with the porous metal structure.
     
    8. The orthopedic implant or device of any one of claims 1-7, wherein the curable calcium phosphate composition or the cured product thereof further comprises a binder, an effervescent agent, demineralized bone, or a combination thereof.
     
    9. The orthopedic implant or device of any one of claims 1-8, wherein:

    the porous metal structure comprises reticulated vitreous carbon foam; and

    the plurality of ligaments of the porous substrate comprise a biocompatible metal coating, the biocompatible metal coating comprising tantalum metal.


     
    10. A method of forming the orthopedic implant or device of any one of claims 1-9, the method comprising injection-perfusing the curable calcium phosphate composition into the porous metal structure, to form the orthopedic implant or device of any one of claims 1-9.
     


    Ansprüche

    1. Orthopädisches Implantat oder orthopädische Vorrichtung, umfassend:
    eine poröse Metallstruktur, umfassend:

    ein poröses Substrat, umfassend eine Vielzahl von Bändern, die Poren des porösen Substrats definieren; und

    eine biokompatible Metallbeschichtung auf der Vielzahl von Bändern des porösen Substrats;

    eine härtbare Calciumphosphatzusammensetzung oder ein ausgehärtetes Produkt davon, das mindestens teilweise mit der porösen Metallstruktur in Kontakt ist, die härtbare Calciumphosphatzusammensetzung umfassend:

    Calciumphosphat;

    einen Perfusionsmodifikator; und

    ein physiologisch annehmbares Fluid,

    wobei der Perfusionsmodifikator 0,5 Gewichtsprozent bis 10 Gewichtsprozent der härtbaren Calciumphosphatzusammensetzung umfasst, und

    wobei der Perfusionsmodifikator Natriumalginat und/oder eine Cellulose ist, ausgewählt aus Methylcellulose, Carboxymethylcellulose, Hydroxypropylmethylcellulose, Hydroxyethylcellulose, einem Salz davon oder einer Kombination davon.


     
    2. Orthopädisches Implantat oder orthopädische Vorrichtung nach Anspruch 1, die poröse Metallstruktur umfassend ein lineares Olefinpolymer oder -copolymer, ein Acrylnitril-Butadien-Styrol (ABS)-Polymer, ein Acrylpolymer, ein Celluloidpolymer, ein Celluloseacetatpolymer, ein cyclisches Olegin-Copolymer (COC), ein Ethylen-Vinylacetat-Polymer (EVA), ein EthylenVinylalkohol-Polymer (EVOH), ein Ethylen-n-Butylacetat-Polymer (EnBA), ein Fluorkunststoff, ein Ionomer, eine Acryl/PVC-Legierung, ein Flüssigkristallpolymer (LCP), ein Polyacetalpolymer (POM oder Acetal), ein Polyacrylatpolymer, ein Polymethylmethacrylatpolymer (PMMA), ein Polyacrylnitrilpolymer (PAN oder Acrylnitril), ein Polyamidpolymer (PA oder Nylon), ein Polyamid-Imid-Polymer (PAI), ein Polyaryletherketonpolymer (PAEK), ein Polybutadien-Polymer (PBD), ein Polybutylen-Polymer (PB), ein Polybutylenterephthalat-Polymer (PBT), ein Polycaprolacton-Polymer (PCL), ein Polychlortrifluorethylen-Polymer (PCTFE), ein Polytetrafluorethylen-Polymer (PTFE), ein Polyethylenterephthalatpolymer (PET), ein Polycyclohexylendimethylenterephthalatpolymer (PCT), ein Polycarbonatpolymer (PC), ein Polyhydroxyalkanoatpolymer (PHA), ein Polyketonpolymer (PK), ein Polyesterpolymer, ein Polyethylenpolymer (PE), ein Polyetheretherketonpolymer (PEEK), ein Polyetherketonketonpolymer (PEKK), ein Polyetherketonpolymer (PEK), ein Polyetherimidpolymer (PEI), ein Polyethersulfonpolymer (PES), ein Polyethylenchlorinatpolymer (PEC), ein Polyimidpolymer (PI), ein Polymilchsäurepolymer (PLA), ein Polymethylpentenpolymer (PMP) ein Polyphenylenoxidpolymer (PPO), ein Polyphenylensulfidpolymer (PPS), ein Polyphthalamidpolymer (PPA), ein Polypropylenpolymer, ein Polystyrolpolymer (PS), ein Polysulfonpolymer (PSU), ein Polytrimethylenterephthalatpolymer (PTT), ein Polyurethanpolymer (PU), ein Polyvinylacetatpolymer (PVA), ein Polyvinylchloridpolymer (PVC), ein Polyvinylidenchloridpolymer (PVDC), ein Polyamidimidpolymer (PAI), ein Polyarylatpolymer, ein Polyoxymethylenpolymer (POM), ein Styrol-Acrylnitril-Polymer (SAN) oder eine Kombination davon.
     
    3. Orthopädisches Implantat oder orthopädische Vorrichtung nach einem der Ansprüche 1 oder 2, wobei die poröse Metallstruktur mindestens eines von Tantal, Titan, Niob, Hafnium, Wolfram, eine Legierung davon oder eine Kombination davon umfasst.
     
    4. Orthopädisches Implantat oder orthopädische Vorrichtung nach einem der Ansprüche 1 bis 3, wobei das poröse Substrat einen Schaumstoff umfasst, der eine geringere Dichte aufweist als die biokompatible Metallbeschichtung darauf.
     
    5. Orthopädisches Implantat oder orthopädische Vorrichtung nach einem der Ansprüche 1 bis 4, wobei die relative Dichte der porösen Metallstruktur 12 % bis 50 % ist, wobei die relative Dichte ein Prozentsatz ist, der durch Dividieren einer tatsächlichen Dichte der porösen Metallstruktur durch eine theoretische Dichte des biokompatiblen Metalls der Beschichtung erlangt wird.
     
    6. Orthopädisches Implantat oder orthopädische Vorrichtung nach einem der Ansprüche 1-5, wobei die spezifische Druckfestigkeit der porösen Metallstruktur mindestens 165,5 MPa ist.
     
    7. Orthopädisches Implantat oder orthopädische Vorrichtung nach einem der Ansprüche 1 bis 6, wobei das ausgehärtete Produkt der härtbaren Calciumphosphatzusammensetzung mindestens teilweise in Kontakt mit der porösen Metallstruktur ist.
     
    8. Orthopädisches Implantat oder orthopädische Vorrichtung nach einem der Ansprüche 1-7, wobei die härtbare Calciumphosphatzusammensetzung oder das ausgehärtete Produkt davon ferner ein Bindemittel, ein efferveszentes Mittel, demineralisierten Knochen oder eine Kombination davon umfasst.
     
    9. Orthopädisches Implantat oder orthopädische Vorrichtung nach einem der Ansprüche 1-8, wobei:

    die poröse Metallstruktur vernetzten glasigen Kohlenstoffschaum umfasst; und

    die Vielzahl von Bändern des porösen Substrats eine biokompatible Metallbeschichtung umfasst,

    die biokompatible Metallbeschichtung umfassend Tantalmetall.


     
    10. Verfahren zum Bilden des orthopädischen Implantats oder der orthopädischen Vorrichtung nach einem der Ansprüche 1 bis 9,
    das Verfahren umfassend Injektionsperfusion der härtbaren Calciumphosphatzusammensetzung in die poröse Metallstruktur, um das orthopädische Implantat oder die orthopädische Vorrichtung nach einem der Ansprüche 1-9 zu bilden.
     


    Revendications

    1. Implant ou dispositif orthopédique comprenant :

    une structure métallique poreuse comprenant :

    un substrat poreux comprenant une pluralité de ligaments qui définissent des pores du substrat poreux ; et

    un revêtement métallique biocompatible sur la pluralité de ligaments du substrat poreux ;

    une composition de phosphate de calcium durcissable ou un produit durci de celle-ci au moins partiellement en contact avec la structure métallique poreuse, la composition de phosphate de calcium durcissable comprenant :

    du phosphate de calcium ;

    un modificateur de perfusion ; et

    un fluide physiologiquement acceptable,

    ledit modificateur de perfusion comprenant 0,5 % en poids à 10 % en poids de la composition de phosphate de calcium durcissable, et

    ledit modificateur de perfusion étant de l'alginate de sodium et/ou une cellulose choisie parmi la méthylcellulose, la carboxyméthylcellulose, l'hydroxypropylméthylcellulose, l'hydroxyéthylcellulose, un sel de celles-ci ou une combinaison de celles-ci.


     
    2. Implant ou dispositif orthopédique selon la revendication 1, ladite structure métallique poreuse comprenant un polymère ou copolymère d'oléfine linéaire, un polymère acrylonitrile butadiène styrène (ABS), un polymère acrylique, un polymère celluloïde, un polymère d'acétate de cellulose, un copolymère d'olégine cyclique (COC), un polymère éthylène-acétate de vinyle (EVA), un polymère éthylène alcool vinylique (EVOH), un polymère éthylène acétate de n-butyle (EnBA), un fluoroplastique, un ionomère, un alliage acrylique/PVC, un polymère à cristaux liquides (LCP), un polymère de polyacétal (POM ou acétal), un polymère de polyacrylate, un polymère de polyméthylméthacrylate (PMMA), un polymère de polyacrylonitrile (PAN ou acrylonitrile), un polymère de polyamide (PA ou nylon), un polymère polyamide-imide (PAI), un polymère de polyaryléthercétone (PAEK), un polymère de polybutadiène (PBD), un polymère de polybutylène (PB), un polymère de polybutylène téréphtalate (PBT), un polymère de polycaprolactone (PCL), un polymère de polychlorotrifluoroéthylène (PCTFE), un polymère de polytétrafluoroéthylène (PTFE), un polymère de polyéthylène téréphtalate (PET), un polymère de polycyclohexylène diméthylène téréphtalate (PCT), un polymère de polycarbonate (PC), un polymère de polyhydroxyalcanoate (PHA), un polymère de polycétone (PK), un polymère de polyester, un polymère de polyéthylène (PE), un polymère de polyétheréthercétone (PEEK), un polymère de polyéthercétonecétone (PEKK), un polymère de polyéthercétone (PEK), un polymère de polyétherimide (PEI), un polymère de polyéthersulfone (PES), un polymère de polyéthylènechlorinate (PEC), un polymère de polyimide (PI), un polymère d'acide polylactique (PLA), un polymère de polyméthylpentène (PMP), un polymère d'oxyde de polyphénylène (PPO), un polymère de polysulfure de phénylène (PPS), un polymère de polyphtalamide (PPA), un polymère de polypropylène, un polymère de polystyrène (PS), un polymère de polysulfone (PSU), un polymère de polytriméthylène téréphtalate (PTT), un polymère de polyuréthane (PU), un polymère de polyacétate de vinyle (PVA), un polymère de polychlorure de vinyle (PVC), un polymère de polychlorure de vinylidène (PVDC), un polymère de polyamideimide (PAI), un polymère de polyarylate, un polymère de polyoxyméthylène (POM), un polymère styrène-acrylonitrile (SAN) ou une combinaison de ceux-ci.
     
    3. Implant ou dispositif orthopédique selon l'une des revendications 1 ou 2, ladite structure métallique poreuse comprenant au moins un élément parmi le tantale, le titane, le niobium, le hafnium, le tungstène, un alliage de ceux-ci ou une combinaison de ceux-ci.
     
    4. Implant ou dispositif orthopédique selon l'une quelconque des revendications 1 à 3, ledit substrat poreux comprenant une mousse présentant une densité plus faible que le revêtement métallique biocompatible sur celui-ci.
     
    5. Implant ou dispositif orthopédique selon l'une quelconque des revendications 1 à 4, la densité relative de la structure métallique poreuse étant de 12 % à 50 %, la densité relative étant un pourcentage obtenu en divisant la densité réelle de la structure métallique poreuse par la densité théorique du métal biocompatible du revêtement.
     
    6. Implant ou dispositif orthopédique selon l'une quelconque des revendications 1 à 5, la résistance spécifique à la compression de la structure métallique poreuse étant d'au moins 165,5 MPa.
     
    7. Implant ou dispositif orthopédique selon l'une quelconque des revendications 1 à 6, ledit produit durci de la composition de phosphate de calcium durcissable étant au moins partiellement en contact avec la structure métallique poreuse.
     
    8. Implant ou dispositif orthopédique selon l'une quelconque des revendications 1 à 7, ladite composition de phosphate de calcium durcissable de produit durci de celle-ci comprenant en outre un liant, un agent effervescent, un os déminéralisé ou une combinaison de ceux-ci.
     
    9. Implant ou dispositif orthopédique selon l'une quelconque des revendications 1 à 8 :

    ladite structure métallique poreuse comprenant une mousse de carbone vitreux réticulé ; et

    ladite pluralité de ligaments du substrat poreux comprenant un revêtement métallique biocompatible, le revêtement métallique biocompatible comprenant du métal de tantale.


     
    10. Procédé de formation de l'implant ou dispositif orthopédique selon l'une quelconque des revendications 1 à 9, le procédé comprenant l'injection-perfusion de la composition de phosphate de calcium durcissable dans la structure métallique poreuse, pour former l'implant ou dispositif orthopédique selon l'une quelconque des revendications 1 à 9.
     




    Drawing























    Cited references

    REFERENCES CITED IN THE DESCRIPTION



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    Patent documents cited in the description




    Non-patent literature cited in the description