Controller module for strut adjustment

Patent metadata

Field	Value
Publication number	US-12440241-B2
Application number	US-202318545044-A
Country	US
Kind code	B2
Filing date	Dec 19, 2023
Priority date	Feb 15, 2022
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

An external fixation system may include first and second fixation rings and a plurality of adjustable length struts. Each adjustable length strut may have two joints, a rod, a tube, and an actuator configured to drive the rod axially relative to the tube to change an effective length of the strut. The system may include a plurality of controller modules each configured to couple to a corresponding strut. The external fixation system may have a manual mode of operation in which the controller modules are not coupled to the struts, and manual actuation of the actuators changes the effective lengths of the struts in discrete length increments. The external fixation system may have an automated mode of operation in which the controller modules are coupled to the struts, and automated actuation of the actuators changes the effective lengths of the struts in infinitesimally small length increments.

First claim

The invention claimed is:

1. An external fixation system comprising:
a first fixation plate;
a second fixation plate;
a plurality of struts, each strut having a first joint proximate a first end of the strut, a second joint proximate a second end of the strut opposite the first end, and an actuator configured to change an effective length of the strut; and
a plurality of controller modules, each controller module configured to couple to a corresponding strut;
wherein in an assembled condition of the external fixation system, the plurality of struts couple the first fixation plate to the second fixation plate;
wherein the external fixation system has a manual mode of operation in which there is no coupling between any of the plurality of controller modules and any of the plurality of struts, and manual actuation of one of the actuators is configured to change the effective length of the corresponding strut; and
wherein the external fixation system has an automated mode of operation in which each of the controller modules is coupled to the corresponding strut, and motorized actuation of one of the actuators is configured to change the effective length of the corresponding strut,
wherein the actuator of each strut includes a strut gear,
wherein each controller module includes a controller gear and a collar, the collar having two prongs defining an open space therebetween, the open space of the collar being sized and shaped to receive a portion of the corresponding strut therein so that, in the automated mode of operation, the controller gear interfaces with the strut gear.

2. The external fixation system of claim 1 , wherein the actuator of each strut includes a strut knob, the strut knob being translatable relative to the strut gear between a first axial position relative to the strut gear and a second axial position relative to the strut gear.

3. The external fixation system of claim 2 , wherein when the strut knob is in the first axial position relative to the strut gear, the strut knob is constrained from rotation relative to the strut, and when the strut knob is in the second axial position relative to the strut gear, the strut knob is rotatable relative to the strut.

4. The external fixation system of claim 1 , wherein in the manual mode of operation, manual actuation of one of the actuators is configured to change the effective length of the corresponding strut in discrete length increments.

5. The external fixation system of claim 4 , wherein in the automated mode of operation, motorized actuation of one of the actuators is configured to change the effective length of the corresponding strut in infinitesimally small length increments.

6. The external fixation system of claim 5 , wherein in the manual mode of operation, a biasing member biases the strut knob to the first axial position.

7. The external fixation system of claim 6 , wherein in the manual mode of operation, each discrete length increment corresponds to a discrete increment of rotation of the strut knob relative to the strut.

8. The external fixation system of claim 7 , wherein in the manual mode of operation, when the strut knob is in the second axial position relative to the strut gear, the biasing member is prevented from transitioning the strut knob to the first axial position between each discrete increment of rotation.

9. The external fixation system of claim 5 , wherein in the automated mode of operation, the controller module maintains the strut knob in the second axial position relative to the strut gear.

10. The external fixation system of claim 5 , wherein each controller module includes a motor configured to rotate the controller gear.

11. The external fixation system of claim 10 , wherein when the controller module is coupled to the corresponding strut, the two prongs are positioned between the strut gear and the strut knob.

12. The external fixation system of claim 11 , wherein each of the two prongs includes a tip portion with a ramped surface, the ramped surface configured to drive the strut knob to the second axial position as the controller module is coupled to the corresponding strut.

13. The external fixation system of claim 5 , wherein when the external fixation system is in the automated mode of operation, each controller module has a dynamization mode configured to cycle between increasing and decreasing the effective length of the strut to axially dynamize the strut with effective length adjustments that are smaller than the discrete length increments in the manual mode of operation.

14. The external fixation system of claim 13 , wherein in the assembled condition of the external fixation system, the external fixation system has a stable construction, and while each controller module is operating in the dynamization mode cycling between increasing and decreasing the effective length of the corresponding strut, the external fixation system remains in the stable construction.

15. The external fixation system of claim 1 , wherein the collar includes a first extension and a second extension defining a distance therebetween, the distance being about equal to a width of a securement area of the strut, the first and second extensions configured to abut the securement area of the strut when the controller module is coupled to the strut to secure the controller module to the strut.

16. The external fixation system of claim 15 , wherein the first extension is flexible and includes a transverse projection extending toward the second extension, a reduced distance between the transverse projection and the second extension being smaller than the width of the securement area of the strut.

17. The external fixation system of claim 16 , wherein, as the controller module is coupled to the strut, contact between the transverse projection and the securement area of the strut is configured to cause the first extension to flex away from the strut until the transverse projection clears an end of the securement area and the first extension snaps back toward the securement area so that the transverse projection impedes the controller module from uncoupling from the strut.

18. The external fixation system of claim 1 , wherein when the controller module is coupled to the corresponding strut, the collar does not fully circumscribe the corresponding strut.

19. The external fixation system of claim 1 , wherein the controller module is configured to couple to the corresponding strut after the external fixation system is in the assembled condition in which the plurality of struts couple the first fixation plate to the second fixation plate.

20. The external fixation system of claim 1 , wherein each controller module includes a housing, and the controller gear protrudes outside of the housing.

Assignees

• Stryker European Operations Ltd

Inventors

• Pak Chulho
• Mannanal Subash K
• Sterrantino Peter
• Roberson Noah
• Kumar Anup
• Nelson Andrew J

Classifications

• A61B17/66

  {Alignment}, compression or distraction mechanisms · CPC title

• A61B17/645

  comprising a framework (A61B17/6425, A61B17/6441 take precedence) · CPC title

• A61B17/62 Primary

  Ring frames, i.e. devices extending around the bones to be positioned ({A61B17/6433} , A61B17/66 take precedence) · CPC title