External fixation

Patent metadata

Field	Value
Publication number	US-10010348-B2
Application number	US-201615073264-A
Country	US
Kind code	B2
Filing date	Mar 17, 2016
Priority date	Sep 4, 2012
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

External fixation systems, and methods for immobilizing joints or fractured bones. An external fixation system may include one or more clamp assemblies connected to one or more rod assemblies at polyaxial joints. Each rod assembly may be length adjustable, and may include a one-way locking mechanism to provisionally lock the length of the rod assembly, and additional locking mechanisms to permanently lock the length of the rod assembly. The system may be deployed pre-assembled as a unit to immobilize a joint or fracture. Another external fixation system further includes a spanning member extending transverse to the rod assemblies. Two or more external fixation systems may be deployed in a stacked configuration on one set of bone pins to immobilize two joints and/or fractures. The systems may be provided in kits including guiding instrumentation, bone pins and pin clamping assemblies for connecting the bone pins to the external fixation systems.

First claim

The invention claimed is:

1. A method for external fixation of a limb, the limb having a first bone portion and a second bone portion, the method comprising:
securing a first bone pin to the first bone portion;
securing a second bone pin to the second bone portion;
attaching a pre-assembled external fixation system to the first bone pin, the external fixation system comprising: first and second clamp assemblies, a first rod assembly, and a one-way locking mechanism; the first rod assembly joined to each of the first and second clamp assemblies, the first and second clamp assemblies at opposite longitudinal ends of the first rod assembly; the first clamp assembly received over the first bone pin;
attaching the external fixation system to the second bone pin, the second clamp assembly received over the second bone pin;
applying tension to distract the first clamp assembly longitudinally away from the second clamp assembly to increase a length of the external fixation system between the first clamp assembly and the second clamp assembly; and
releasing the tension on the first clamp assembly, wherein when the tension on the first clamp assembly is released the one-way locking mechanism automatically engages to prevent the length of the external fixation system from decreasing, wherein the one-way locking mechanism automatically engages the first rod assembly at a non-discrete location to prevent the length of the external fixation system from decreasing.

2. The method of claim 1 , comprising:
opening a package; and
removing the pre-assembled external fixation system as a single unit from the package.

3. The method of claim 1 , wherein the first rod assembly comprises a removable tab, the method comprising:
removing the tab to activate the one-way locking mechanism, wherein prior to removal of the tab, the external fixation system is freely adjustable to increase or decrease the length of the external fixation system between the first clamp assembly and the second clamp assembly.

4. The method of claim 1 , comprising a second rod assembly, e second rod assembly joined to each of the first and second clamp assemblies.

5. The method of claim 4 , wherein the first clamp assembly is identical to the second clamp assembly, and wherein the first rod assembly is identical to the second rod assembly.

6. The method of claim 1 , wherein the first rod assembly comprises an inner tubular member received in an outer tubular member, wherein the one-way locking mechanism is a first locking mechanism, wherein the one-way locking mechanism is mounted to the outer tubular member, wherein activating the one-way locking mechanism comprises:
directly engaging the one-way locking mechanism with the inner tubular member to prevent the inner tubular member from translating relative to the outer tubular member in a first direction.

7. The method of claim 6 , wherein the one-way locking mechanism comprises a collar encircling the inner tubular member, wherein the collar frictionally engages with the inner tubular member to prevent the inner tubular member from translating relative to the outer tubular member in the first direction.

8. The method of claim 6 , comprising:
activating a second locking mechanism to further prevent the inner tubular member from translating relative to the outer tubular member in the first direction and also in a second direction opposite the first direction.

9. The method of claim 8 , wherein the first rod assembly comprises the second locking mechanism, the second locking mechanism comprising a clamp encircling the outer tubular member, the method comprising:
compressing the clamp around the outer tubular member; and
compressing the outer tubular member around the inner tubular member.

10. The method of claim 8 , comprising:
activating a third locking mechanism to further prevent the inner tubular member from translating relative to the outer tubular member.

11. The method of claim 10 , wherein the first rod assembly comprises the third locking mechanism, the third locking mechanism comprising a plug received in the inner tubular member, the method comprising drawing the plug within the inner tubular member to expand a portion of the inner tubular member.

12. The method of claim 1 , comprising:
polyaxially adjusting the position of the first rod assembly relative to the first clamp assembly; and
compressing the first clamp assembly about the first rod assembly to lock the position of the first rod assembly relative to the first clamping assembly.

13. The method of claim 1 , comprising:
locking the first clamping assembly to the first bone pin.

14. The method of claim 13 , wherein the first clamping assembly houses a first fixation plate and a second fixation plate, wherein locking the first clamping assembly to the first bone pin comprises:
passing the first bone pin through the first and second fixation plates; and
deforming the first and second fixation plates to bind against the first bone pin.

15. The method of claim 1 , comprising:
passing a third bone pin into the first clamping assembly; and
securing the third bone pin to the limb.

16. A method for external fixation of a limb, the limb having a first bone portion and a second bone portion, the method comprising:
securing a first bone pin to the first bone portion;
securing a second bone pin to the second bone portion;
attaching a pre-assembled external fixation system to the first bone pin, the external fixation system comprising: first and second clamp assemblies, a first rod assembly comprising a removable tab, and a one-way locking mechanism; the first rod assembly joined to each of the first and second clamp assemblies, the first and second clamp assemblies at opposite longitudinal ends of the first rod assembly; the first clamp assembly received over the first bone pin;
attaching the external fixation system to the second bone pin, the second clamp assembly received over the second bone pin;
removing the tab to activate the one-way locking mechanism, wherein prior to removal of the tab, the external fixation system is freely adjustable to increase or decrease the length of the external fixation system between the first clamp assembly and the second clamp assembly;
applying tension to distract the first clamp assembly longitudinally away from the second clamp assembly to increase a length of the external fixation system between the first clamp assembly and the second clamp assembly; and
releasing the tension on the first clamp assembly, wherein when the tension on the first clamp assembly is released the one-way locking mechanism automatically engages to prevent the length of the external fixation system from decreasing.

Assignees

• Zimmer Inc

Inventors

• Myers Thomas H
• O'Toole Robert V
• Nascone Jason W
• Lorang Douglas M
• Fauth Andrew R
• Triplett Daniel J

Classifications

• A61B17/6458 Primary

  with pin-clamps fixed at ends of connecting element · CPC title

• A61B17/6416

  with non-continuous, e.g. hinged, pin-clamp connecting element (A61B17/6425, A61B17/6441 take precedence) · CPC title

• A61B17/6425

  specially adapted to be fitted across a bone joint · CPC title