Transcutaneous implant for skeletal attachment of external prosthetic devices

• US 10,390,975 B2
• Filed: 08/19/2016
• Issued: 08/27/2019
• Est. Priority Date: 09/10/2012
• Status: Active Grant

• Current Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Inventors: Hugate, Ronald
• Primary Examiner(s): Bahena, Christie L
• Application Number:
  US15/241,180
• Publication Number:
  US 20160354216A1
• Time in Patent Office: 1,103 Days
• CPC Class Codes: A61F 2/2814 Bone stump caps
• CPC Class Codes: A61F 2/30771 applied in original prostheses, e.g. holes or grooves
• CPC Class Codes: A61F 2/78 Means for protecting prostheses or for attaching them to the body, e.g. bandages, harnesses, straps, or stockings for the limb stump
• CPC Class Codes: A61F 2002/30011 differing in porosity
• CPC Class Codes: A61F 2002/30028 differing in tissue ingrowth capacity, e.g. made from both ingrowth-promoting and ingrowth-preventing parts
• CPC Class Codes: A61F 2002/30884 Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
• CPC Class Codes: A61F 2002/3092 having an open-celled or open-pored structure
• CPC Class Codes: A61F 2002/3093 for promoting ingrowth of bone tissue
• CPC Class Codes: A61F 2002/6845 Clutches
• CPC Class Codes: A61F 2002/7887 for connecting limb exoprostheses to the stump bone

Abstract

Provided herein are devices and methods for connecting a transcutaneous external prosthetic device to a bone, such as a bone of an amputee. The device is a two-piece transcutaneous implant device to provide reversible connection for ease of implantation, reliability, and relatively easy access for removal, while maximizing tissue ingrowth to reduce risk of infection and attendant adverse outcomes. The devices provided herein comprise a prosthetic interface and a bone anchor. A through-hole that traverses a longitudinal length of the prosthetic interface and at least a longitudinal portion of the bone anchor receives a fastener to reversibly connect the prosthetic interface to the bone anchor implanted in bone. A connector may connect to a failsafe element which, in turn, connects to an external prosthetic device.

Claims

1. A transcutaneous device to anchor an external prosthetic device to a bone, the transcutaneous device comprising:

a bone anchor implantable into bone and including a male end configured to extend from the bone, wherein the male end has a threaded passage for receiving a fastener, the passage configured to extend along a longitudinal length of the male end external to the bone;

a prosthetic interface configured for implantation external to the bone and configured for soft tissue ingrowth and vascularization after implantation, the prosthetic interface having a male connection configured to extend external to the soft tissue and configured to mate with the external prosthetic device, the prosthetic interface having a female connection configured to receive the male end of the bone anchor therein, wherein the prosthetic interface has a through bore that extends longitudinally from the male connection to the female connection, and wherein the threaded passage and the through bore are substantially aligned to receive the fastener to couple the prosthetic interface to the bone anchor when the male end of the bone anchor is received in the female connection of the prosthetic interface; and

a failsafe comprising a proximal portion and a distal portion, the proximal portion couplable to the prosthetic interface external to the bone and the soft tissue at a proximal end, and couplable to the external prosthetic device at a distal end, wherein the failsafe includes a shear pin connecting the proximal portion and the distal portion, the shear pin configured to separate the proximal portion from the distal portion to separate the prosthetic device from the prosthetic interface when a predetermined shear load is applied to the failsafe, wherein a shaft of the failsafe includes a medial/lateral bending notch configured to separate the prosthetic device from the prosthetic interface when a predetermined medial/lateral bending load is applied to at least one of the proximal portion and the distal portion, and wherein the failsafe includes an anterior/posterior bending notch configured to separate the prosthetic device from the prosthetic interface when a predetermined anterior/posterior bending load is applied to the failsafe.

2. The transcutaneous device of claim 1, wherein the male end of the bone anchor is received in the female connection so as to be inaccessible from external to the soft tissue and the bone when the fastener couples the prosthetic interface to the bone anchor.

3. The transcutaneous device of claim 1, wherein the fastener is configured to reversibly secure the prosthetic interface to the bone anchor and is removable from the bone anchor and the male connection of the prosthetic interface external to the soft tissue and the bone.

4. The transcutaneous device of claim 1, wherein the bone anchor is configured to be accessible by removing the fastener from the bone anchor and the prosthetic interface and then by removing the prosthetic interface from the bone anchor.

5. The transcutaneous device of claim 1, wherein the fastener comprises a bolt that is reversibly connected to the bone anchor, wherein threads on the bolt and the threaded passage allow the bolt to be removed from the bone anchor and the through bore of the prosthetic interface allows the fastener to be removed from the prosthetic interface to allow for decoupling and removal of the prosthetic interface from the bone anchor.

6. The transcutaneous device of claim 1, wherein the fastener comprises a distraction bolt configured to provide an extraction force for facilitating removal of the prosthetic interface from the soft tissue.

7. The transcutaneous device of claim 1, wherein the male end of the bone anchor is tapered and the female connection of the prosthetic interface is similarly tapered to create a press-fit connection between the prosthetic interface and the bone anchor when the male end of the bone anchor is received in the female connection of the prosthetic interface.

8. The transcutaneous device of claim 1, wherein the male end of the bone anchor and the female connection of the prosthetic interface are configured to create a press-fit connection between the prosthetic interface and the bone anchor when the male end of the bone anchor is received in the female connection of the prosthetic interface.

9. The transcutaneous device of claim 1, wherein the prosthetic interface has a bulbous portion with a shaped tissue ingrowth surface proximal of the male connection, wherein the shaped tissue ingrowth surface is configured for soft tissue ingrowth and vascularization after implantation and the male connection extends less than half a longitudinal length of the bone anchor.

10. The transcutaneous device of claim 9, wherein the shaped tissue ingrowth surface comprises:

an apex region concentrically positioned on a distal portion of a central body outer surface;

a rounded radial edge portion; and

a convex outer-facing surface extending between the apex region and the rounded radial edge portion.

11. The transcutaneous device of claim 10, wherein the prosthetic interface includes a ring configured to mechanically stabilize the shaped tissue ingrowth surface.

12. The transcutaneous device of claim 10, wherein the prosthetic interface includes a suture ring positioned at the apex region of the shaped tissue ingrowth surface to provide an anchoring point for skin upon implantation.

15. The transcutaneous device of claim 1, wherein:

the male end has a threaded passage for receiving a fastener, the passage extending along a longitudinal length of the male end; and

the prosthetic interface has a through bore that extends longitudinally from the male connection to the female connection, and wherein the threaded passage and the through bore are substantially aligned to receive the fastener to couple the prosthetic interface to the bone anchor when the male end of the bone anchor is received in the female connection of the prosthetic interface.

16. The transcutaneous device of claim 15, wherein the fastener is configured to reversibly secure the prosthetic interface to the bone anchor and is removable from the bone anchor and the male connection of the prosthetic interface external to the soft tissue and the bone.

17. The transcutaneous device of claim 15, wherein the bone anchor is configured to be accessible by removing the fastener from the bone anchor and the prosthetic interface and by removing the prosthetic interface from the bone anchor.

18. The transcutaneous device of claim 15, wherein the fastener comprises a bolt that is reversibly connected to the bone anchor, wherein threads on the bolt and the threaded passage allow the bolt to be removed from the bone anchor and the through bore of the prosthetic interface allows for removal of the fastener from the prosthetic interface to allow for decoupling and removal of the prosthetic interface from the bone anchor.

19. The transcutaneous device of claim 15, wherein the fastener comprises a distraction bolt configured to provide an extraction force for facilitating removal of the prosthetic interface from the soft tissue.

13. A transcutaneous device to anchor an external prosthetic device to a bone, the transcutaneous device comprising:

a bone anchor implantable into bone and including a tapered male end configured to extend from a bone ingrowth portion and from the bone;

a prosthetic interface configured for implantation external to bone and configured for soft tissue ingrowth and vascularization after implantation, the prosthetic interface having a male connection configured to extend external to the soft tissue and configured to mate with the external prosthetic device, the prosthetic interface having a tapered female connection configured to receive the tapered male end of the bone anchor therein to create a press-fit connection between the prosthetic interface and the bone anchor external to the soft tissue; and

a failsafe comprising a proximal portion couplable to the prosthetic interface external to the bone and the soft tissue at a proximal end of the proximal portion, the proximal portion couplable to the external prosthetic device at a distal end of the proximal portion, wherein the failsafe includes a distal portion and a shear pin connecting the proximal portion and the distal portion, the shear pin configured to separate the prosthetic device from the prosthetic interface when a predetermined shear load is applied to the failsafe, wherein a shaft of the failsafe includes a first bending notch configured to mechanically break to separate the prosthetic device from the prosthetic interface when a predetermined first bending load is applied to the failsafe, and wherein the failsafe includes a second bending notch configured to separate the prosthetic device from the prosthetic interface when a predetermined second bending load is applied to the failsafe.

14. The transcutaneous device of claim 13, wherein the male end of the bone anchor is received in the female connection so as to be inaccessible from external to the soft tissue and the bone when the prosthetic interface is connected the bone anchor.

20. A transcutaneous device to anchor an external prosthetic device to a bone, the transcutaneous device comprising:

a bone anchor implantable into bone and including a tapered male end configured to extend from the bone; and

a prosthetic interface configured for implantation external to bone and configured for soft tissue ingrowth and vascularization after implantation, the prosthetic interface having a male connection configured to extend external to the soft tissue and configured to mate with the external prosthetic device, the prosthetic interface having a tapered female connection configured to receive the tapered male end of the bone anchor therein to create a press-fit connection between the prosthetic interface and the bone anchor; and

a failsafe comprising a proximal portion and a distal portion, the proximal portion couplable to the prosthetic interface external to the bone and the soft tissue at a proximal end, and couplable to the external prosthetic device at a distal end, wherein the failsafe includes a shear pin connecting the proximal portion and the distal portion, the shear pin configured to separate the proximal portion from the distal portion to separate the prosthetic device from the prosthetic interface when a predetermined shear load is applied to at least one of the proximal portion and the distal portion, wherein a shaft of the failsafe includes a medial/lateral bending notch configured to mechanically break to separate the prosthetic device from the prosthetic interface when a predetermined medial/lateral bending load is applied to the failsafe, and wherein the failsafe includes an anterior/posterior bending notch configured to separate the prosthetic device from the prosthetic interface when a predetermined anterior/posterior bending load is applied to the failsafe.