Spacer molds with releasable securement

• US 8,414,286 B2
• Filed: 12/04/2008
• Issued: 04/09/2013
• Est. Priority Date: 10/29/2008
• 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 M.
• Primary Examiner(s): HAUTH, GALEN H
• Application Number:
  US12/328,159
• Publication Number:
  US 20100102484A1
• Time in Patent Office: 1,587 Days
• Field of Search: 425/577, 425/451.9, 425/DIG.221, 425/56, 264/328.7
• US Class Current: 425/577
• 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 2/38 for elbows or knees
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2/4684 Trial or dummy prostheses
• CPC Class Codes: A61F 2002/30329 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2002/30604 modular
• 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 2002/30957 using a positive or a negative model, e.g. moulds
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2310/00353 Bone cement, e.g. polymethylmethacrylate or PMMA
• CPC Class Codes: B29C 45/66 mechanical

Abstract

A mold for forming a temporary prosthesis has at least two mold members at least partially separable from each other. The at least two mold members cooperatively define a generally enclosed interior cavity for forming the temporary prosthesis. The mold has a securement structure mounted on the at least two mold members for securing the at least two mold members to each other during the forming of the temporary prosthesis. The securement structure is removable from the at least two mold members by hand and without the use of a tool.

Claims

1. A mold for forming a temporary prosthesis comprising:

a first mold and a second mold being at least partially separable from each other, the first mold and the second mold defining a first enclosed interior cavity when the first mold is secured to the second mold in a first position, the first mold and the second mold defining a second enclosed interior cavity when the first mold is secured to the second mold in a second position, the second interior cavity being a different size than the first interior cavity, in the second position the entirety of one of the first and second molds is disposed in a different position relative to the other of the first and second molds than in the first position; and

an initially separate non-threaded securement structure detachably mounted on the first mold and the second mold for securing the first mold and the second mold to each other during the forming of the temporary prosthesis, the securement structure operable to selectively secure the first mold to the second mold in the first position and the second position.

2. The mold of claim 1 wherein the securement structure secures the first mold and the second mold to each other while the mold receives pressurized, curable material for forming the temporary prosthesis.

3. The mold of claim 1 wherein the securement structure includes at least one pin disposed so that moving the at least one pin axially secures and unsecures the first mold and the second mold to and from each other.

4. The mold of claim 3 wherein the securement structure includes a finger pull ring mounted on the at least one pin.

5. The mold of claim 1 wherein the mold is adjustable to form the temporary prosthesis with or without a stem.

6. The mold of claim 1 being provided in alternative configurations wherein at least one of the first interior cavity and the second interior cavity is shaped to form the temporary prosthesis to comprise a body being provided in either of a first shape specifically configured for placement on a left leg or a second shape specifically configured for placement on a right leg.

7. The mold of claim 6 wherein at least one of the first interior cavity and the second interior cavity is shaped to provide the body with a medial side and a stem having a central axis generally inclined toward the medial side.

8. The mold of claim 6 wherein at least one of the first interior cavity and the second interior cavity is shaped to provide the body with a medial side, a main portion, and a posterior flange generally extending in a superior-inferior direction from the main portion, the flange having a distal, superior tip disposed on the medial side of the body.

9. The mold of claim 1 wherein the securement structure includes at least one pin, wherein the first mold and the second mold are secured together by the at least one pin, one of the first and second molds defining at least one hole for receiving the pin, and the other of the first and second molds having a retainer for restricting movement of the pin.

10. The mold of claim 9 wherein one of the first and second mold defines a plurality of holes for alternatively receiving the at least one pin and to define different secured positions of the second mold relative to the first mold.

11. The mold of claim 1 wherein one of the first or second mold comprises at least one extension defining at least one hole, the securement structure including a pin received within the hole, and wherein the other of the first or second mold having a retainer defining at least one through-opening for receiving the at least one extension.

13. The mold of claim 1 wherein both the first mold and the second mold are generally tub shaped, wherein one of the first mold and second mold is configured to fit into the other of the first mold or second mold.

14. The mold of claim 1 wherein the first mold is configured for forming a side of the temporary prosthesis that will engage bone, the first mold having a stem forming section defining a stem cavity of the first interior cavity and the second interior cavity, the mold further comprising a plug received in the stem cavity for optionally closing the stem cavity to restrict formation of a stem on the prosthesis.

15. The mold of claim 1 further comprising a bearing member inserted into one of the first and second molds to become a part of the temporary prosthesis.

16. The mold of claim 1 wherein the temporary prosthesis is a tibial knee prosthesis and wherein multiple holes provide an adjustable superior-inferior thickness of the tibial knee prosthesis.

17. The mold of claim 1, wherein:

the first interior cavity includes;

a first cavity anterior/posterior dimension that corresponds to an anterior/posterior dimension of the temporary prosthesis;

a first cavity medial/lateral dimension that corresponds to a medial/lateral dimension of the temporary prosthesis; and

a first cavity proximal/distal dimension that corresponds to a proximal/distal dimension of the temporary prosthesis;

the second interior cavity includes;

a second cavity anterior/posterior dimension equal to the first cavity anterior/posterior dimension;

a second cavity medial/lateral dimension equal to the first cavity medial/lateral dimension; and

a second cavity proximal/distal dimension different than the first cavity proximal/distal dimension.

12. A mold for forming a temporary prosthesis comprising:

at least two mold members being at least partially separable from each other, the at least two mold members cooperatively defining a generally enclosed interior cavity for forming the temporary prosthesis;

an initially separate non-threaded securement structure detachably mounted on the at least two mold members for securing the at least two mold members to each other during the forming of the temporary prosthesis, the securement structure being removable from the at least two mold members by hand, and without the use of a tool;

wherein the at least two mold members includes a first mold and a second mold secured together by the securement structure to cooperatively define the interior cavity therebetween, the first mold and second mold being configured to be secured at one of a plurality of alternative positions relative to each other to provide alternative dimensions for the interior cavity;

wherein one of the first or second mold comprises at least one extension defining at least one hole, the securement structure including a pin received within the hole;

wherein the other of the first or second mold having a retainer defining at least one through-opening for receiving the at least one extension, wherein the other of the first or second mold comprises a sidewall, and wherein the retainer comprises at least one arm extending from the sidewall and defining the at least one through-opening, an insertion side of the through-opening, and an exit side of the through-opening, and

wherein the at least one extension is configured to be placed through the at least one through-opening for placing the at least one hole exteriorly of the exit side of the through-opening for receiving the pin, whereby the pin retains the extension in the arm.

18. The mold of claim 12 wherein the securement structure includes a finger pull ring mounted on the pin.

19. The mold of claim 12 wherein the mold is adjustable to form the temporary prosthesis with or without a stem.

20. The mold of claim 12 wherein the extension defines a plurality of holes for alternatively receiving the pin and to define different secured positions of the second mold relative to the first mold.

21. The mold of claim 12 wherein both the first mold and the second mold are generally tub shaped, wherein one of the first mold and second mold is configured to fit into the other of the first mold or second mold.

22. The mold of claim 12 wherein the first mold is configured for forming a side of the temporary prosthesis that will engage bone, the first mold having a stem forming section defining a stem cavity of the interior cavity, the mold further comprising a plug received in the stem cavity for optionally closing the stem cavity to restrict formation of a stem on the prosthesis.

23. The mold of claim 12 further comprising a bearing member inserted into one of the first and second molds to become a part of the temporary prosthesis.

24. The mold of claim 12 wherein the temporary prosthesis is a tibial knee prosthesis and wherein multiple holes provide an adjustable superior-inferior thickness of the tibial knee prosthesis.

25. The mold of claim 12 wherein the securement structure secures the first mold and the second mold to each other while the mold receives pressurized, curable material for forming the temporary prosthesis.