Spacer mold and methods therefor

• US 8,801,983 B2
• Filed: 06/11/2013
• Issued: 08/12/2014
• Est. Priority Date: 12/07/2007
• Status: Active Grant

• Current Assignee: Zimmer Orthopaedic Surgical Products (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Zimmer Orthopaedic Surgical Products (Zimmer Biomet Holdings, Inc.)
• Inventors: Haney, Sean, Sporer, Scott, Hawkins, Michael E
• Primary Examiner(s): Davis, Robert B
• Application Number:
  US13/914,860
• Publication Number:
  US 20130344186A1
• Time in Patent Office: 427 Days
• Field of Search: 425/117, 425/567, 249/55, 249/61, 249/83, 249/91, 249/158, 264/39, 264/328.1
• US Class Current: 264/39
• CPC Class Codes: A61F 2/30942 for designing or making customized prostheses, e.g. using templates, CT or NMR scans, finite-element analysis or CAD-CAM techniques
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/36 Femoral heads ; Femoral endoprostheses
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30672 temporary
• CPC Class Codes: A61F 2002/30677 Means for introducing or releasing pharmaceutical products, e.g. antibiotics, into the body
• CPC Class Codes: A61F 2002/30693 Air venting means
• CPC Class Codes: A61F 2002/30957 using a positive or a negative model, e.g. moulds
• CPC Class Codes: A61F 2002/30975 made of two halves
• CPC Class Codes: A61F 2250/0007 for adjusting length
• CPC Class Codes: A61F 2310/00353 Bone cement, e.g. polymethylmethacrylate or PMMA
• CPC Class Codes: A61F 2310/00952 Coating, pre-coating or prosthesis-covering structure made of bone cement, e.g. pre-applied PMMA cement mantle
• CPC Class Codes: B29C 33/10 with incorporated venting means
• CPC Class Codes: B29C 33/306 Exchangeable mould parts, e.g. cassette moulds, mould inserts moulds with exchangeable mould parts for injection moulding B29C45/2673; mounting of exchangeable mould inserts for injection moulding B29C45/2675
• CPC Class Codes: B29C 33/308 Adjustable moulds for injection moulding B29C45/376
• CPC Class Codes: B29L 2031/7532 Artificial members, protheses

Abstract

A hip spacer mold forming a spacer with a spacer stem connected to a spacer head has a stem portion for forming a spacer stem. The hip spacer mold also has a plurality of interchangeable head modules configured for alternatively forming spacer heads of a plurality of different predetermined sizes. The head modules are configured to be disposed adjacent the stem portion.

Claims

1. A spacer mold for forming an articulating prosthesis having a head and a stem, comprising:

a head portion defining a head molding chamber; and

a stem portion, separable from the head portion, defining an elongated stem cavity and having a superior end portion configured to be disposed adjacent to the head portion, the superior end portion having at least one superior end portion wall disposed to form a lower wall of the head molding chamber when the head portion and stem portion are disposed adjacent to each other.

2. The spacer mold of claim 1, wherein the lower wall of the head molding chamber formed by the superior end portion wall is a bottom wall or a side wall of the head molding chamber.

3. The spacer mold of claim 1, wherein the head portion comprises at least one head module defining the head molding chamber, the at least one head module configured to be received within the superior end portion.

4. The spacer mold of claim 1, wherein the stem cavity and the head molding chamber are in communication with each other when the head portion and the stem portion are disposed adjacent to each other.

5. The spacer mold of claim 1, further comprising a securing member configured to releasably hold the head portion adjacent to the stem portion.

6. A spacer mold system for forming a modular articulating prosthesis having an integral head and stem, comprising:

at least one head module defining a head molding chamber; and

at least one stem portion, separable from the at least one head module, the at least one stem portion defining a circumferentially enclosed stem cavity and having a superior end portion configured to receive the at least one head module, the stem cavity and the head molding chamber in communication with each other when the at least one head module is received within the superior end portion of the at least one stem portion.

7. The spacer mold of claim 6, wherein the at least one head module comprises a plurality of head modules, and wherein the at least one stem portion comprises a plurality of stem portions, each one of the plurality of stem portions configured to be compatible with each one of the plurality of head modules.

8. The spacer mold of claim 7, wherein each one of the plurality of head modules comprises a pair of head module members configured to be mated to each other to cooperatively define the head molding chamber.

9. The spacer mold of claim 6, further comprising a port in communication with the stem cavity and the head molding chamber when the at least one head module is received within the superior end portion.

10. The spacer mold of claim 6, further comprising a securement member configured to hold the at least one head module adjacent to the at least one stem portion.

11. A method of forming a customized articulating prosthesis having an integral head and stem, comprising:

providing or receiving a plurality of head modules, each one of the plurality of head modules defining a head cavity;

providing or receiving a plurality of stem portions, each one of the plurality of stem portions comprising a port and defining a stem cavity, the stem cavity in communication with the port;

selecting one of the plurality of head modules;

selecting one of the plurality of stem portions;

placing the selected head module adjacent to the selected stem portion such that the head cavity is in communication with the stem cavity;

receiving a curable material within the selected head module and the selected stem portion; and

allowing the curable material to cure while the selected head module and the selected stem portion are held adjacent to each other.

12. The method of claim 11, wherein the head cavities in each of the head modules define different diameters.

13. The method of claim 11, wherein the stem cavities in each of the stem portions define different maximum diameters.

14. The method of claim 11, wherein the selected stem portion comprises a superior end portion, and wherein the step of placing comprises receiving the selected head module within the superior end portion.

15. The method of claim 14, wherein the superior end portion includes an opening in communication with the stem cavity and the head cavity.

16. The method of claim 11, further comprising, before the step of receiving the curable material, holding the selected head module in fixed relation to the selected stem portion.

17. The method of claim 11, further comprising, before the step of placing the selected head module adjacent the selected stem portion, depositing a portion of the curable material within at least one of the head cavity of the selected head module or the stem cavity of the selected stem portion.

18. The method of claim 11, further comprising providing or receiving a securement cover including a threaded portion, and wherein the step of placing the selected head module adjacent to the selected stem portion comprises placing the head module within the securement cover and releasably engaging the threaded portion of the securement cover with a threaded feature of the superior end portion.

19. The method of claim 11, wherein the port comprises an injection port, and wherein the step of receiving the curable material comprises receiving the curable material through the injection port.

20. The method of claim 19, wherein the step of receiving the curable material comprises receiving the curable material within the head cavity and the stem cavity through the injection port.