Polymeric plate bendable without thermal energy and methods of manufacture

• US 20050273104A1
• Filed: 06/06/2005
• Published: 12/08/2005
• Est. Priority Date: 06/07/2004
• Status: Active Grant

• Current Assignee: Degima GmbH
• Original Assignee: Degima GmbH
• Inventors: Oepen, Randolf von, Tschakaloff, Alexander
• Granted Patent: US 7,717,946 B2
• Time in Patent Office: Days
• US Class Current: 606/285
• CPC Class Codes: A61B 17/8085 with pliable or malleable elements or having a mesh-like structure, e.g. small strips A61B17/8071, A61B17/8076 take precedence
• CPC Class Codes: A61B 2017/00004 (bio)absorbable, (bio)resorbable, resorptive for implantable prostheses A61F2210/0004
• CPC Class Codes: A61B 2017/00526 Methods of manufacturing
• CPC Class Codes: Y10S 606/907 Composed of particular material or coated

Abstract

An implantable plate for providing support to a bone of a subject when affixed thereto includes a polymeric body comprised of a biocompatible polymer having a desired amount of polymer molecule orientation in a first direction so that the plate can be bent to conform with a contour of the bone of the subject. The polymeric body includes a top surface, a bottom surface, and at least one fastener portion. The fastener portion includes a recess and a fastener hold that is configured for receiving a fastener when affixed to the bone of the subject. A method of manufacturing the implantable plate includes: (1) injection molding a biocompatible polymeric composition into a polymeric body within an injection mold; (2) removing the polymeric body from the injection mold; and (3) forming at least one fastener hole within polymeric body.

Claims

1. A molded body for use in preparing an implantable plate, the molded body comprising:

a polymeric body comprised of biocompatible polymers having a desired amount of polymer molecule orientation, wherein the desired amount of polymer molecular orientation enables the polymeric body to be capable of bending without heat so as to conform to a contour of a bone of a subject, the polymeric body including a fastener hole template configured for being formed into a fastener hole for receiving a fastener, and the polymeric body being substantially devoid of a joint line.

2. A molded body as in claim 1, wherein the polymeric body further includes at least one plate portion in the form of an implantable plate that can be affixed to a broken bone to provide support thereto during healing, the implantable plate portion including at least one recess in substantially a frustoconical shape with at least one fastener hole template on a bottom portion of the at least one recess.

3. A molded body as in claim 2, wherein the biocompatible polymer is comprised of at least one polymer selected from the group consisting of a poly(alpha-hydroxy esters), polylactic acids, polylactides, poly-L-lactide, poly-DL-lactide, poly-L-lactide-co-DL-lactide, polyglycolic acids, polyglycolide, polylactic-co-glycolic acids, polyglycolide-co-lactide, polyglycolide-co-DL-lactide, polyglycolide-co-L-lactide, polyanhydrides, polyanhydride-co-imides, polyesters, polyorthoesters, polycaprolactones, polyesters, polyanydrides, polyphosphazenes, polyester amides, polyester urethanes, polycarbonates, polytrimethylene carbonates, polyglycolide-co-trimethylene carbonates, poly(PBA-carbonates), polyfumarates, polypropylene fumarate, poly(p-dioxanone), polyhydroxyalkanoates, polyamino acids, poly-L-tyrosines, poly(beta-hydroxybutyrate), polyhydroxybutyrate-hydroxyvaleric acids, high-density polyethylenes, ultra-high-density polyethylenes, low-density polyethylenes, polypropylenes, polyacrylates, polymethylmethacrylates, polyethylmethacrylates, polysulfones, polyetheretherketones, polytetrafluoroethylenes, polyurethanes, polystyrenes, polystyrene-co-butadienes, and combinations thereof.

4. An implantable plate for providing support to a bone of a subject when affixed thereto, the plate comprising:

a polymeric body comprised of a biodegradable polymer having a desired amount of polymer molecule orientation in a first direction so that the plate can be bent without heat to conform with a contour of the bone of the subject, the polymeric body including;

at least one fastener portion including a fastener hole defined by a wall, the fastener hole formed by being drilled through the at least one fastener portion so that the at least one fastener portion is substantially devoid of a joint line.

5. An implantable plate as in claim 4, further comprising:

a recess defined by a recess surface adjacent with the fastener hole, the fastener hole being configured for receiving a fastener when affixed to the bone of the subject.

6. An implantable plate as in claim 4, wherein the desired amount of polymer molecule orientation results in a plate that is configured to shrink less than about 6% of an original dimension after being immersed within a fluid maintained 37°

C. for 10 days.

7. An implantable plate as in claim 4, wherein the desired amount of polymer molecule orientation results in a plate that can be bent without heat to an angle of less than or about 90 degrees.

8. An implantable plate as in claim 7, wherein the desired amount of polymer molecule orientation results in a plate that can be bent without heat to an angle of less than or about 30 degrees.

9. An implantable plate as in claim 7, wherein the implantable plate can retain substantially the bent angle after being affixed to the bone of the subject for at least 12 weeks.

10. An implantable plate as in claim 9, wherein the implantable plate can retain substantially the bent angle after being affixed to the bone of the subject for at least 6 weeks.

11. An implantable plate as in claim 4, wherein the desired amount of polymer molecule orientation includes less than 40% of the polymer molecules being oriented in substantially one direction.

12. An implantable plate as in claim 11, wherein the desired amount of polymer molecule orientation is from about 10% to about 30% of the polymer molecules being oriented in substantially one direction.

13. An implantable plate as in claim 4, further comprising at least one of a magnesium fiber, micro-porous silicon fiber, nano-porous silicon fiber, organic fiber, or ceramic fiber.

14. A method of manufacturing an implantable plate for providing support to a bone of a subject when affixed thereto, the method comprising:

injection molding a biocompatible polymeric composition into a polymeric body within an injection mold cavity, wherein at least a portion of the polymeric body is configured to be an implantable plate at least partially defined by a top surface and bottom surface;

removing the polymeric body from the injection mold, wherein the polymeric body has a desired amount of polymeric molecules oriented in substantially a first direction so as to be bendable without heat; and

forming at least one fastener hole within the implantable plate portion after being removed from the injection mold, wherein the at least one fastener hole extends from the top surface to the bottom surface.

15. A method as in claim 14, wherein the forming the at least one fastener hole includes drilling holes in the implantable plate portion.

16. A method as in claim 14, wherein the injection molding includes passing the polymeric composition through a gate that is configured for orienting the desired amount of polymeric molecules in substantially the first direction.

17. A method as in claim 16, further comprising configuring the gate to have at least one aperture that imparts a shear stress to the polymeric composition passing through the gate, wherein the at least one aperture is pre-designed to achieve the desired amount of polymeric molecule orientation.

18. A method as in claim 17, wherein the at least one aperture has a cross-sectional length from about 10% to about 60% of at least one of an average cross-sectional length of the cavity or a cross-sectional length of a runner.

19. A method as in claim 14, further comprising orienting the polymer molecules so that the implantable plate is capable of being bent without heat to an angle of less than or about 90 degrees.

20. A method as in claim 19, wherein the implantable plate is capable of being bent without heat to an angle of less than or about 30 degrees.

21. A method as in claim 14, further comprising orienting the polymer molecules so that the implantable plate shrinks less than about 6% of an original dimension when maintained in a fluid at 37°

C. for 10 days.

22. A method as in claim 14, further comprising configuring the implantable plate to be biodegradable within a medium maintained at 37°

C.

23. A method as in claim 14, further comprising configuring the implantable plate to biodegrade so that the bone supports more weight in comparison to the implantable plate after 6 weeks.

24. A method as in claim 14, wherein the desired amount of polymer molecule orientation includes less than about 40% of the polymer molecules being oriented in substantially one direction.

25. A method as in claim 14, further comprising configuring the injection molding to use a mold having a cavity that is substantially devoid of any pins or protrusions extending through the cavity so as to result in an implantable plate substantially devoid of joint lines.

26. A method as in claim 14, further comprising introducing fibers into the injection mold during the injection molding process so as to be encapsulated within the polymeric body, the fibers being selected from the group consisting of magnesium fiber, micro-porous silicon fiber, nano-porous silicon fiber, organic fiber, ceramic fiber, and combinations thereof.

27. A method as in claim 14, further comprising configuring a portion of the plate to be capable of delivering a drug after being implanted.

28. A method as in claim 27, wherein the portion is a polymeric coating on the plate.

29. A method as in claim 14, further comprising at least one of the following:

mixing the polymeric composition in a mixer;

extruding the polymeric composition as a thermoplastic extrudate;

heating the polymeric composition before being introduced into the injection mold

introducing the polymeric composition into the injection mold under pressure;

cooling the polymeric body after being removed from the injection mold;

drilling a fastener hole with at least one of a drill bit or a laser;

forming threads in a wall that defines the at least one fastener hole;

separating the implantable plate portion form the polymeric body;

finishing the implantable plate portion into an biocompatible implantable plate;

or

configuring the implantable plate to be biodegradable.