# US 12,458,729 B2 · Oxide layer-containing zirconium-niobium alloy tibial plateau prosthesis having bone trabecula and preparation method

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- Number: US 12,458,729 B2
- Document ID: US12458729B2
- Status: Granted
- Kind: B2
- Application number: 17/916,708
- Filed: 2021-06-21
- Published: 2023-10-26
- Granted: 2025-11-04
- Earliest claimed: 2020-10-30
- Assignees: Just Medical Devices (Tianjin) Co., Ltd.
- Applicants: Just Medical Devices (Tianjin) Co., Ltd.
- Inventors: Lu Liu; Yu Cao; Jianyu Li; Jingkang Zhang; Hongxiu Zhou
- Web page: https://patentgrep.com/patent/US12458729B2

## CPC

- A61L 27/306: {Other specific inorganic materials not covered by A61L27/303 - A61L27/32}
- C23C 8/02: Pretreatment of the material to be coated (C23C8/04 takes precedence)
- A61F 2/3094: {Designing or manufacturing processes}
- A61F 2/389: {Tibial components (A61F2/3868 takes precedence)}
- A61L 27/047: {Other specific metals or alloys not covered by A61L27/042 - A61L27/045 or A61L27/06}
- A61L 27/50: Materials characterised by their function or physical properties {, e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials}
- A61L 27/56: Porous materials, {e.g. foams or sponges}
- B22F 3/15: Hot isostatic pressing
- B22F 5/10: of articles with cavities or holes, not otherwise provided for in the preceding subgroups
- B22F 7/002: {of porous nature}
- B22F 7/008: {characterised by the composition}
- B22F 10/14: by jetting of binder onto a bed of metal powder
- B22F 10/20: Direct sintering or melting
- B22F 10/64: by thermal means (control of energy beam parameters for post heating B22F10/364)
- B33Y 10/00: Processes of additive manufacturing
- B33Y 40/20: Post-treatment, e.g. curing, coating or polishing
- B33Y 80/00: Products made by additive manufacturing
- C22C 16/00: Alloys based on zirconium
- C22F 1/186: {of zirconium or alloys based thereon}
- C23C 8/10: Oxidising
- A61F 2002/30011: {differing in porosity}
- A61F 2002/30884: {Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity}
- A61F 2002/3092: {having an open-celled or open-pored structure}
- A61F 2002/30985: {using three dimensional printing [3DP]}
- A61F 2310/00089: Zirconium or Zr-based alloys
- A61F 2310/00095: Niobium or Nb-based alloys
- A61L 2400/18: Modification of implant surfaces in order to improve biocompatibility, cell growth, fixation of biomolecules, e.g. plasma treatment
- A61L 2420/02: Methods for coating medical devices
- A61L 2430/02: for reconstruction of bones; weight-bearing implants
- B22F 2998/10: Processes characterised by the sequence of their steps
- B22F 2999/00: Aspects linked to processes or compositions used in powder metallurgy
- Y02P 10/25: Process efficiency
- A61L: METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES (preservation of bodies or disinfecting characterised by the agents employed A01N; preserving, e.g. sterilising, food or foodstuffs A23; preparations for medical, dental or toiletry purposes A61K)
- C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04)
- A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C)
- B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B33Y: ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- C22C: ALLOYS (treatment of alloys C21D, C22F)
- C22F: CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS (surface treatment of metallic material involving at least one process provided for in class C23 and at least one process covered by this subclass, C23F17/00)
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS

## Abstract

The present disclosure discloses a tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer and a preparation method thereof. The preparation method uses zirconium niobium alloy powder as raw material, conducting a 3D printing for one-piece molding to obtain an intermediate product of the tibial plateau, performing hot isostatic pressing and cryogenic oxidation to obtain the tibial plateau prosthesis comprising a proximal trabecular layer and a distal trabecular layer; the pore size and porosity of the proximal trabecular layer are evenly arranged, and the distal trabecular layer are partitioned; the topological structure of the trabeculae of the tibial plateau prosthesis is gradiently distributed from three dimensions; the micro-strain in the 64%-72% region of the finite element model of the tibial plateau bone tissue is between the minimum effective strain threshold and the supraphysiological strain threshold, which increases the mechanical adaptation of the prosthesis.

## Claims

### Claim 1

A preparation method of the tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer comprising the following steps:
1) Using zirconium-niobium alloy powder as a raw material, conducting a 3D printing for one-piece molding, and obtaining a first intermediate of the tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer, putting the first intermediate into a Sinter-hip furnace, heating to 1250° C.-1400° C. under inert gas protection, placing at a constant pressure of 140 MPa-180 MPa for 1 h to 3 h, reducing to a normal pressure, cooling to below 200° C. with the furnace, taking the first intermediate out, and obtaining a second intermediate of the tibial plateau prosthesis with trabeculae;
2) Placing the second intermediate product in a programmable thermostat to cool to −80° C. to −120° C. at a rate of 1° C./min, keeping the second intermediate product at a constant temperature for 5 h to 10 h, and taking the second intermediate product out of the programmed thermostat; placing the second intermediate product in a liquid nitrogen for 16 h to 36 h, and adjusting the temperature to a room temperature so as to obtain a third intermediate;
3) Placing the third intermediate product in a programmable thermostat to cool to −80° C. to −120° C. at a rate of 1° C./min, and placing the third intermediate product at a constant temperature for 5 h to 10 h, taking the third intermediate product out of the programmed thermostat, placing the third intermediate in the liquid nitrogen for 16 h to 36 h and adjusting the temperature to room temperature so as to obtain a fourth intermediate;
4) Machining, finishing, polishing, cleaning, and drying the fourth intermediate product, and obtaining a fifth intermediate, where the upper surface roughness of the fifth intermediate tibial plateau support is Ra≤0.050 μm;
5) Putting the fifth intermediate product into a tube furnace, introducing a atmospheric pressure inert gas containing 5% to 15% of oxygen in percentage by mass, heating to 500° C. to 700° C. at 5° C./min to 20° C./min, and cooling to 400° C. to 495° C. at 0.4° C./min to 0.9° C./min, and cooling to be below 200° C. sequentially, taking the fifth intermediate product out to obtain the tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer;
the structure of the tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer is the same as its first intermediate product, second intermediate product, third intermediate product, fourth intermediate product, and fifth intermediate product;
wherein the inert gas is helium or argon;
the tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer includes a kidney-shaped plateau support (1), a Y-shaped protrusion (3) is provided on the upper surface of the inwardly curved portion of the kidney-shaped plateau support (1), a rear groove is (5) provided on the lateral surfaces of the two branches of the Y-shaped protrusion (3), a curved protrusion (2) is provided on the upper surface of the outwardly curved portion of the kidney-shaped plateau support (1) corresponding to the Y-shaped protrusion (3); a front groove (6) is arranged on the inner side of the curved protrusion (2), the middle part of the lower surface of the kidney-shaped plateau support (1) is provided with a handle (4), and a trabeculae (9) is arranged on the lower surface of the kidney-shaped plateau support (1) excepting connecting the handle (4), the trabeculae (9) is composed of a proximal trabecular layer (21) which is closed to the plateau support (1) and a distal trabecular layer (20) which is away from the plateau support (1); the pore size and porosity of the proximal trabecular layer (21) are evenly arranged, and the distal trabecular layer (20) are partitioned into three partitions; the transverse diameter (10) of the corresponding kidney-shaped plateau support (1) is divided into a first section (25), a second section (26) and a third section (27) by a first marking point (11) and a second marking point (12); and the lengths of the first section, the second section and the third section are 25%-38%, 24%-50% and 25%-38% of the transverse diameter of the kidney-shaped plateau support (1), respectively, a first section line (13) passes through the first marking point (11), a second section line (14) passes through the second marking point (12); and the first section line (13) and the second section line (14) are straight lines or arcs, which separate the distal trabecular layer (20) into an inner portion trabeculae (15), an intermediate portion trabeculae (16) and an outer portion trabeculae (17); the pore size and porosity of the trabeculae in the inner portion (15) are sequentially larger than those in the outer portion (17) and the intermediate portion (16).

### Claim 2 (depends on 1)

The preparation method according to claim 1, wherein the chemical composition of the zirconium-niobium alloy powder in percentage by mass is respectively 85.6%-96.5% of Zr, 1.0%-12.5% of Nb, and the rest are unavoidable impurities; where a particle size of the zirconium-niobium alloy powder ranges from 45 to 150 μm.

### Claim 3 (depends on 1)

The preparation method according to claim 1, wherein the specific steps for adjusting the temperature in steps 2) and 3) are: increasing the temperature to −120° C. to −80° C. and keeping the constant temperature for 3 h to 5 h; then increasing the temperature to −40° C. to −20° C. and keeping the constant temperature for 3 h to 5 h; then increasing the temperature to 4° C. to 8° C. and keeping the constant temperature for 1 h to 3 h and then increasing the temperature.

### Claim 4 (depends on 1)

The preparation method according to claim 1, wherein the trabeculae of the proximal trabecular layer (21) has a pore size of 0.36 mm to 0.50 mm, a porosity of 55%-65%, a through-hole ratio of 100%, and a thickness of 0.2 mm-1 mm.

### Claim 5 (depends on 1)

The preparation method according to claim 1, wherein the first section line (13) and the second section line (14) of the distal trabecular layer (20) are straight lines and are arranged in parallel or in splayed arrangement; an included angle (18) between the first section line (13) and the transverse diameter (10) of the corresponding kidney-shaped plateau support (1) is 100° to 60°, an included angle (19) between the second section line (14) and the transverse diameter (10) of the corresponding kidney-shaped plateau support (1) is 80° to 120°.

### Claim 6 (depends on 1)

The preparation method according to claim 1, wherein the pore size of the inner portion trabeculae (15) of the distal trabecular layer (20) ranges from 1.00 mm to 1.10 mm, the porosity ranges from 77.6% to 85%; the pore size of the intermediate portion trabeculae (16) ranges from 0.74 mm to 0.85 mm, the porosity ranges from 70.0% to 74.7%; the pore size of the outer portion trabeculae (17) ranges from 0.86 mm to 0.99 mm, the porosity ranges from 74.8%-77.5%; and a through-hole ratio is 100%, and the thickness of the distal trabecular layer (20) is 0.5 mm to 3 mm.

### Claim 7 (depends on 1)

The preparation method according to claim 1, wherein the handle (4) is selected from one of the followings: a reducing pipe connected with a supporting plate, a reducing pipe with a closed bottom connected with a supporting plate, a cross-shaped stiffened plate or a curved cross-shaped stiffened plate.

### Claim 8 (depends on 1)

A tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer prepared by the preparation method according to claim 1.

### Claim 9 (depends on 2)

A tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer prepared by the preparation method according to claim 2.

### Claim 10 (depends on 3)

A tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer prepared by the preparation method according to claim 3.

### Claim 11 (depends on 4)

A tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer prepared by the preparation method according to claim 4.

### Claim 12 (depends on 5)

A tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer prepared by the preparation method according to claim 5.

### Claim 13 (depends on 6)

A tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer prepared by the preparation method according to claim 6.

### Claim 14 (depends on 7)

A tibial plateau prosthesis with trabeculae containing zirconium-niobium alloy on oxidation layer prepared by the preparation method according to claim 7.