Artificial cotyloid cavity

• US 6,136,033 A
• Filed: 07/06/1998
• Issued: 10/24/2000
• Est. Priority Date: 11/08/1995
• Status: Expired due to Fees

• Current Assignee: Biomet Merck GmbH
• Original Assignee: Stratec Biomedical GmbH
• Inventors: Suemer, Aykut
• Primary Examiner(s): Isabella, David J.
• Application Number:
  US09/068,408
• Time in Patent Office: 841 Days
• Field of Search: 623/18, 623/19, 623/22, 623/23
• US Class Current: 623/22.21
• CPC Class Codes: A61F 2/30771 applied in original prostheses, e.g. holes or grooves
• CPC Class Codes: A61F 2/30965 Reinforcing the prosthesis by embedding particles or fibres during moulding or dipping
• CPC Class Codes: A61F 2/34 Acetabular cups
• CPC Class Codes: A61F 2/4609 of acetabular cups
• CPC Class Codes: A61F 2002/30324 differing in thickness
• CPC Class Codes: A61F 2002/30332 Conically- or frustoconically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30405 made by screwing complementary threads machined on the parts themselves
• CPC Class Codes: A61F 2002/30589 Sealing means
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30795 Blind bores, e.g. of circular cross-section
• CPC Class Codes: A61F 2002/3082 Grooves
• CPC Class Codes: A61F 2002/3462 having a frustoconical external shape, e.g. entirely frustoconical
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2250/0036 differing in thickness
• CPC Class Codes: A61F 2310/00023 Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/00161 Carbon; Graphite
• CPC Class Codes: A61F 2310/00179 Ceramics or ceramic-like structures

Abstract

An artificial cotyloid socket having a domal outer shell (1) and a domal inner shell (2) subtending between them a cavity (3). Each of the outer and inner shells (1, 2) having a domal wall that merges into a rim (5, 6). The outer and inner shells are undetachably joined to each other at their rims (5, 6). The rim of the outer shell is reinforced and disposed relatively beneath a circle of merging (7). The circle of merging is defined by the intersection of the outer shell domal wall and the outer shell rim. A thickness of the wall continuously increases as one moves from a pole (4) of the outer shell toward the circle of merging (7).

Claims

1. An artificial cotyloid socket having a domal outer shell (1) and a domal inner shell (2) subtending there between a cavity (3), each of said outer and inner shells (1, 2) having a domal wall that merges into a rim (5. 6), said outer and inner shells being undetachably joined to each other at said rims rims (5, 6), said outer shell rim (5) being reinforced and being disposed relatively beneath a circle of merging (7), said circle of merging being defined by the intersection of said outer shell domal wall and said outer shell rim, wherein a thickness of said wall continuously increases as one moves from a pole (4) of the outer shell toward the circle of merging (7).

2. Cotyloid socket as claimed in claim 1, wherein the circle of merging (7) is located between 20 to 40 degrees'"'"' latitude of said outer shell (1).

3. Cotyloid socket as claimed in claim 2, wherein the wall thickness of the outer shell (1) is less than 0.30 mm at said pole (4).

4. Cotyloid socket as claimed in claim 3, wherein the wall thickness of the outer shell (1) at said pole (4) is between about 30-60% of the wall thickness of the outer shell (1) at the circle of merging (7).

5. Cotyloid socket as claimed in claim 4, wherein the rim (5) of the outer shell (1) includes an inner surface having threads (12) formed thereon, said inner shell rim (6) including an outer surface having threads (13) formed thereon, said outer shell threads cooperating with said inner shell threads to permit said inner and outer shells to be threadably attached to one another.

6. Cotyloid socket as claimed in claim 5, wherein the rim (6) of the inner shell (2) comprises a conical outer surface (8) and the rim (5) of the outer shell (1) comprises a conical inner surface (9), said conical inner surface being connected in a frictionally-locking manner to the conical outer surface (8).

7. Cotyloid socket as claimed in claim 6, wherein the rim (5) of the outer shell (1) includes a conical outer surface (10), said outer shell conical outer surface being adapted for engagement with a bone and having axial rim grooves (16) and defining a three-dimensional structure (11).

8. Cotyloid socket as claimed in claim 7, wherein the three-dimensional structure (11) has a depth of between about 0.3 to 0.8 mm.

9. Cotyloid socket as claimed in claim 8, wherein the outer shell (1) is made of a material selected from the group consisting of:

pure titanium and titanium alloy.

10. Cotyloid socket as claimed in claim 9, wherein the inner shell (2) is made of a material selected from the group consisting of:

cobalt-chromium-molybdenum alloys, ceramics, polyethylene, and carbon-fiber reinforced carbons.

11. Cotyloid socket as claimed in claim 10, wherein the rim (6) of the inner shell (2) has at least three blind holes (15) formed therein, said holes extend substantially parallel to an axis of rotation (14) of the cotyloid socket.

12. Cotyloid socket as claimed in claim 2, wherein the circle of merging (7) is located between 25 to 35 degrees'"'"' latitude of said outer shell (1).

13. Cotyloid socket as claimed in claim 2, wherein the wall thickness of the outer shell (1) is less than 0.25 mm at said pole (4).

14. Cotyloid socket as claimed in claim 7, wherein the three-dimensional structure (11) has a depth of between about 0.4 to 0.6 mm.