Modular endoprosthesis shaft system with rotation element

Patent metadata

Field	Value
Publication number	US-12257155-B2
Application number	US-202318301873-A
Country	US
Kind code	B2
Filing date	Apr 17, 2023
Priority date	Dec 15, 2017
Publication date	Mar 25, 2025
Grant date	Mar 25, 2025

Abstract

The invention relates to an endoprosthesis shaft system for elongate bones, comprising an anchoring part and a shaft, which is formed from module elements that can be coupled by means of a plug-in connection, wherein a mutual rotation of the elements along the shaft is adjustable and is blocked by means of an anti-rotation mechanism. In order to adjust the rotation, a rotation piece is provided as a further module element, which has a self-contained rotation adjustment device and a clamping device as a mechanism for blocking the rotation. The rotation piece comprises two end faces for the plug-in connection and a sleeve. The invention provides, with the rotation piece, a particular module element for the shaft, which as a structural unit allows both an adjustment of the rotation and a blocking against undesired rotation in a self-contained unit.

First claim

The invention claimed is:

1. An endoprosthesis shaft system for elongate bones, comprising:
an anchoring part; and
a shaft, which is formed from module elements that can be coupled by means of a plug connection,
wherein a mutual rotation of the elements along the shaft is adjustable and is blocked by means of an anti-rotation mechanism, and
wherein, in order to adjust the rotation, a rotation piece is provided as a further module element, which has a self-contained rotation adjustment device and a clamping device as a means for blocking the rotation, wherein the rotation piece has two end faces, for the plug connection, and a jacket, wherein the self-contained rotation adjustment device comprises a distal end and a proximal end, the distal end configured to extend into a portion of the jacket, wherein a perimeter of the distal end is smaller than a diameter of the proximal end.

2. The endoprosthesis shaft system comprising a modular shaft system as claimed in claim 1 , wherein the rotation piece functions as a lengthening module element.

3. The endoprosthesis shaft system as claimed in claim 1 , wherein the clamping device has a central access for an actuation member for applying/releasing the block.

4. The endoprosthesis shaft system as claimed in claim 1 , wherein an access for adjusting the anti-rotation mechanism is provided through an opening of the jacket.

5. The endoprosthesis shaft system as claimed in claim 1 , wherein a cap nut is provided which, in an inserted state, delimits an inner space of the rotation piece.

6. The endoprosthesis shaft system as claimed in claim 5 , wherein the cap nut has a smooth jacket on which coupling elements for a clamping tool are formed.

7. The endoprosthesis shaft system as claimed in claim 6 , wherein the cap nut has a round jacket and wherein the coupling elements are arranged offset in a circumferential direction.

8. The endoprosthesis shaft system as claimed in claim 5 , wherein the cap nut has a central passage through which an element of the plug connection is guided, wherein the element is connected directly to a bearing insert of the rotation adjustment device.

9. The endoprosthesis shaft system as claimed in claim 8 , wherein the bearing insert and an element of the plug connection are combined.

10. The endoprosthesis shaft system as claimed in claim 5 ,
wherein a rotary bearing of the rotation adjustment device is arranged completely in the rotation piece,
wherein the clamping device further comprises a locking disk which acts on the rotary bearing and which is arranged in an inner space at a bottom of a bearing bush, and
wherein the cap nut, in a first, clamped position, presses the locking disk onto the rotary bearing and thus blocks it, and, in a second, open position, the locking disk comes free from the rotary bearing, such that the rotary bearing is movable.

11. The endoprosthesis shaft system as claimed in claim 5 , wherein the cap nut, with its outer face, forms a part of the jacket of the rotation piece.

12. The endoprosthesis shaft system as claimed in claim 1 , wherein a rotary bearing of the rotation adjustment device is arranged completely in the rotation piece.

13. The endoprosthesis shaft system as claimed in claim 12 , wherein the rotary bearing comprises a cylindrical bearing journal and a complementary bearing bush, wherein the bearing journal and a bearing sleeve form a fit that is free of play and does not jam.

14. The endoprosthesis shaft system as claimed in claim 12 , wherein the clamping device further comprises a locking disk which acts on the rotary bearing and which is arranged in an inner space at a bottom of a bearing bush.

15. The endoprosthesis shaft system as claimed in claim 12 , wherein the rotation piece is configured in two parts, with an attached spacer part.

16. The endoprosthesis shaft system as claimed in claim 15 , wherein the spacer part is at one end connected to the rotation piece for conjoint rotation therewith and, at its other end, carries a mating element of the plug connection.

17. The endoprosthesis shaft system as claimed in claim 16 , wherein a rotary bearing of the rotation adjustment device is arranged completely in the rotation piece, and
wherein the spacer part and/or the bearing insert are replaceable by other ones with a different plug connector.

18. The endoprosthesis shaft system as claimed in claim 1 , wherein a portion of the rotation adjustment device is configured to thread into a portion of the jacket.

19. The endoprosthesis shaft system as claimed in claim 1 , wherein an access for adjusting the anti-rotation mechanism is provided through an opening of the jacket.

20. The endoprosthesis shaft system as claimed in claim 1 , wherein a rotary bearing of the rotation adjustment device is arranged completely in the rotation piece.

Assignees

• Link Waldemar Gmbh Co

Inventors

• Link Helmut D
• Borchers Udo
• Erb Gunnar

Classifications

• A61F2002/3674

  Connections of proximal parts to distal parts · CPC title

• A61F2002/30474

  using an intermediate sleeve interposed between both prosthetic parts to be coupled · CPC title

• A61F2002/30367

  with additional means for preventing said rotation · CPC title

• A61F2002/30365

  with additional means for limiting said rotation · CPC title

• A61F2002/30364

  Rotation about the common longitudinal axis · CPC title