Method for fastening an implant to bone tissue and corresponding implant system

• US 9,289,301 B2
• Filed: 12/21/2012
• Issued: 03/22/2016
• Est. Priority Date: 04/20/2007
• Status: Active Grant

• Current Assignee: Woodwelding AG
• Original Assignee: Woodwelding AG
• Inventors: Mayer, Jorg, Mueller, Andrea
• Primary Examiner(s): Anderson, Gregory
• Assistant Examiner(s): Dang, Son
• Application Number:
  US13/724,251
• Publication Number:
  US 20130123928A1
• Time in Patent Office: 1,187 Days
• US Class Current: 1/1
• CPC Class Codes: A61B 17/68 Internal fixation devices , including fasteners and spinal fixators, even if a part thereof projects from the skin bone staples A61B17/0642
• CPC Class Codes: A61F 2/30 Joints
• CPC Class Codes: A61F 2/30721 Accessories
• CPC Class Codes: A61F 2/30749 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/3804 for elbows
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2/4081 Glenoid components, e.g. cups
• CPC Class Codes: A61F 2/42 for wrists or ankles; for hands, e.g. fingers; for feet, e.g. toes
• CPC Class Codes: A61F 2002/30065 thermoplastic, i.e. softening or fusing when heated, and hardening and becoming rigid again when cooled
• CPC Class Codes: A61F 2002/30331 made by longitudinally pushing a protrusion into a complementarily-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2002/30332 Conically- or frustoconically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30451 soldered or brazed or welded
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30772 Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/30777 Oblong apertures
• CPC Class Codes: A61F 2002/3082 Grooves
• CPC Class Codes: A61F 2002/30845 with cutting edges
• CPC Class Codes: A61F 2002/30878 with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
• CPC Class Codes: A61F 2002/30892 : parallel
• CPC Class Codes: A61F 2002/3412 : with pins or protrusions, e.g. non-sharp pins or protrusions projecting from a shell surface
• CPC Class Codes: A61F 2210/0071 : thermoplastic
• 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 2220/0058 : soldered or brazed or welded

Abstract

An implant designed e.g. as a replacement for an articulating surface of a human or animal joint is secured to the bone tissue with the aid of a plurality of fasteners (3). The implant (2) comprises a bone side to be brought into contact with the bone tissue, which bone side is equipped with a plurality of fastening structures restricted to this bone side. The fasteners (3) comprise a distal and a proximal side, wherein the distal side is equipped for being anchored in bone tissue and the proximal side is equipped for being connected with one of the fastening structures of the implant (2). The distal sides of the fasteners (3) are anchored in the bone tissue of the appropriately prepared bone and the implant (2) is then attached to the anchored fasteners (3) by connecting the fastening structures with the proximal sides of the fasteners (3), wherein the implant (2) is pressed against the proximal sides of the anchored fasteners (3). The connection between fastening structures and proximal sides of the fasteners is a positive fit connection, a material fit connection and/or a force fit connection.

Claims

1. An implant system to be fastened to human or animal bone tissue, the system comprising:

an implant comprising a bone side to be brought into contact with the bone tissue, the bone side of the implant being equipped with a plurality of fastening structures restricted to said bone side; and

a plurality of fasteners, each with a distal side and a proximal side, wherein the distal side is equipped for anchoring the fastener in the bone tissue and the proximal side is equipped for a connection with the fastening structures of the implant so that the proximal side of the fastener does not reach to a side of the implant facing away from the bone side,

wherein at least one of the following conditions holds;

one of the fastening structures and of the proximal sides of the fasteners comprises undercut recesses and the other one of the fastening structures and of the proximal sides of the fasteners comprises protrusions which are insertable or snappable into the undercut recesses;

one of the fastening structures and of the proximal sides of the fasteners comprises undercut recesses and the other one of the fastening structures and of the proximal sides of the fasteners comprises a thermoplastic material embeddable in the undercut recesses when melted or at least softened;

one of the fastening structures and the proximal sides of the fasteners comprises conical protrusions and the other one of the fastening structures and the proximal sides of the fasteners comprises conical recesses, wherein pressing the conical protrusions into the conical recesses results in a press fit connection;

the fastening structures and the proximal sides of the fasteners comprise thermoplastic material capable of making a material connection, wherein on a side of the implant different from the bone side an axis of application of energy for liquefying the thermoplastic material is defined, and wherein said axis of application of energy is not parallel to an axis of at least one of the fasteners;

wherein the distal sides of the fasteners are equipped with a material which is liquefiable by mechanical oscillation for being anchored with the aid of mechanical oscillation.

2. The system according to claim 1, wherein one of the fastening structures and of the proximal sides of the fasteners comprises undercut recesses.

3. The system according to claim 2, wherein the other one of the fastening structures and of the proximal sides of the fasteners comprises a thermoplastic material embeddable in the undercut recesses when melted or at least softened.

4. The system according to claim 1, wherein one of the fastening structures and the proximal sides of the fasteners comprises conical protrusions and the other one of the fastening structures and the proximal sides of the fasteners comprises conical recesses, wherein pressing the conical protrusions into the conical recesses results in a press fit connection.

5. The system according to claim 1, wherein the fastening structures and the proximal sides of the fasteners comprise thermoplastic material capable of making a material connection.

6. The system according to claim 1, wherein the fastening structures are equipped for being connected to the proximal sides of the fasteners simultaneously.

7. The system according to claim 1, wherein the fasteners are pin-shaped or tongue- or blade-shaped.

8. The system according to claim 1, wherein the implant is a joint implant replacing an articulating surface.

9. The system according to claim 1, wherein the implant is designed for a bone supporting or stabilizing function.

10. An implant system to be fastened to human or animal bone tissue for replacing an articulating surface of a human or animal joint, the system comprising:

an implant comprising a bone side to be brought into contact with the bone tissue, the bone side of the implant being equipped with a plurality of fastening structures restricted to said bone side, and an articulating surface side, the articulating surface side facing away from the bone side, wherein one of the following conditions holds;

the articulating surface side forms the articulating surface,

the articulating surface side comprises a structure for receiving a bearing element, and the implant system further comprises a bearing element shaped to be received by the articulating surface side and forming an articulating surface, the implant system further comprising a plurality of fasteners, each with a distal side and a proximal side, wherein the distal side is equipped for anchoring the fastener in the bone tissue and the proximal side is equipped for a connection with the fastening structures of the implant so that the proximal side of the fastener does not reach to the articulating surface side,

wherein at least one of the following conditions holds;

one of the fastening structures and of the proximal sides of the fasteners comprises undercut recesses and the other one of the fastening structures and of the proximal sides of the fasteners comprises protrusions which are insertable or snappable into the undercut recesses;

one of the fastening structures and of the proximal sides of the fasteners comprises undercut recesses and the other one of the fastening structures and of the proximal sides of the fasteners comprises a thermoplastic material embeddable in the undercut recesses when melted or at least softened;

one of the fastening structures and the proximal sides of the fasteners comprises conical protrusions and the other one of the fastening structures and the proximal sides of the fasteners comprises conical recesses, wherein pressing the conical protrusions into the conical recesses results in a press fit connection;

wherein the distal sides of the fasteners are equipped with a material which is liquefiable by mechanical oscillation for being anchored with the aid of mechanical oscillation.

11. The system according to claim 10, wherein the fasteners consist of the liquefiable material.

12. The system according to claim 10, wherein the fasteners comprise a core of a metal, the core being at least partially surrounded by the liquefiable material.

13. The system according to claim 10, wherein the fasteners comprise a perforated sheath and an element of the liquefiable material inserted or insertable in the sheath element.

14. The system according to claim 10 being configured for replacing a tibia plateau or for resurfacing one of a glenoid cavity, an acetabulum, an elbow, wrist, ankle or digital joint, or a femoral head.

15. The system according to claim 10, wherein the implant is made of a metal or a ceramic material or a composite material or a crystalline polymer having a glass transition temperature above 100°

C. or a thermosetting polymer.

16. The system according to claim 10 wherein the fastening structures are equipped for being connected to the proximal sides of the fasteners simultaneously.

17. The system according to claim 10, wherein the fasteners are pin-shaped or tongue- or blade-shaped.

18. An implant system to be fastened to human or animal bone tissue, the system comprising:

an implant comprising a bone side to be brought into contact with the bone tissue, the bone side of the implant being equipped with a plurality of fastening structures restricted to said bone side; and

a plurality of fasteners, each with a distal side and a proximal side, wherein the distal side is equipped for anchoring the fastener in the bone tissue and the proximal side is equipped for a connection with the fastening structures of the implant so that the proximal side of the fastener does not reach to a side of the implant facing away from the bone side,

wherein at least one of the following conditions holds;

one of the fastening structures and of the proximal sides of the fasteners comprises undercut recesses and the other one of the fastening structures and of the proximal sides of the fasteners comprises protrusions which are insertable or snappable into the undercut recesses;

one of the fastening structures and of the proximal sides of the fasteners comprises undercut recesses and the other one of the fastening structures and of the proximal sides of the fasteners comprises a thermoplastic material embeddable in the undercut recesses when melted or at least softened;

one of the fastening structures and the proximal sides of the fasteners comprises conical protrusions and the other one of the fastening structures and the proximal sides of the fasteners comprises conical recesses, wherein pressing the conical protrusions into the conical recesses results in a press fit connection;

the fastening structures and the proximal sides of the fasteners comprise thermoplastic material capable of making a material connection, wherein on a side of the implant different from the bone side an axis of application of energy for liquefying the thermoplastic material is defined, and wherein said axis of application of energy is not parallel to an axis of at least one of the fasteners;

wherein one of the fastening structures and the proximal sides of the fasteners comprises conical protrusions and the other one of the fastening structures and the proximal sides of the fasteners comprises conical recesses, wherein pressing the conical protrusions into the conical recesses results in a press fit connection;

wherein the distal sides of the fasteners are equipped with a material which is liquefiable by mechanical oscillation for being anchored with the aid of mechanical oscillation.

20. The system according to claim 18, wherein the distal sides of the fasteners are equipped with a thread for being anchored by screwing.

19. An implant system to be fastened to human or animal bone tissue, the system comprising:

an implant comprising a bone side to be brought into contact with the bone tissue, the bone side of the implant being equipped with a plurality of fastening structures restricted to said bone side; and

a plurality of fasteners, each with a distal side and a proximal side, wherein the distal side is equipped for anchoring the fastener in the bone tissue and the proximal side is equipped for a connection with the fastening structures of the implant so that the proximal side of the fastener does not reach to a side of the implant facing away from the bone side,

wherein at least one of the following conditions holds;

one of the fastening structures and of the proximal sides of the fasteners comprises undercut recesses and the other one of the fastening structures and of the proximal sides of the fasteners comprises a thermoplastic material embeddable in the undercut recesses when melted or at least softened;

one of the fastening structures and the proximal sides of the fasteners comprises conical protrusions and the other one of the fastening structures and the proximal sides of the fasteners comprises conical recesses, wherein pressing the conical protrusions into the conical recesses results in a press fit connection;

the fastening structures and the proximal sides of the fasteners comprise thermoplastic material capable of making a material connection, wherein on a side of the implant different from the bone side an axis of application of energy for liquefying the thermoplastic material is defined, and wherein said axis of application of energy is not parallel to an axis of at least one of the fasteners;

wherein the implant is a joint implant replacing an articulating surface;

wherein the distal sides of the fasteners are equipped with a material which is liquefiable by mechanical oscillation for being anchored with the aid of mechanical oscillation.

21. The system according to claim 19, wherein the distal sides of the fasteners are equipped with a pointed or sharp end for being malleted into the bone tissue.

22. The system according to claim 19, wherein the implant is a tibia plateau replacement implant.

23. The system according to claim 19, wherein the implant is a resurfacing implant for a glenoid cavity, for an acetabulum, for an elbow, wrist, ankle or digital joint, or for a femoral head.

24. A kit of parts, the kit comprising:

an implant system according to claim 19 and

further comprising a template with a bone side adapted to the bone side of the implant and with through bores in positions corresponding with the positions of the fastening structures on the implant and/or a pressing tool being adapted to a joint side of the implant.

25. The system according to claim 19, wherein the other one of the fastening structures and of the proximal sides of the fasteners comprises a thermoplastic material embeddable in the undercut recesses when melted or at least softened.

26. The system according to claim 19, wherein one of the fastening structures and the proximal sides of the fasteners comprises conical protrusions and the other one of the fastening structures and the proximal sides of the fasteners comprises conical recesses, wherein pressing the conical protrusions into the conical recesses results in a press fit connection.

27. The system according to claim 19, wherein the fastening structures and the proximal sides of the fasteners comprise thermoplastic material capable of making a material connection.

28. The system according to claim 19, wherein the fastening structures are equipped for being connected to the proximal sides of the fasteners simultaneously.

29. The system according to claim 19, wherein the fasteners are pin-shaped or tongue- or blade-shaped.