Modular surgical instruments and related methods

Patent metadata

Field	Value
Publication number	US-11439441-B2
Application number	US-202016815945-A
Country	US
Kind code	B2
Filing date	Mar 11, 2020
Priority date	Sep 5, 2017
Publication date	Sep 13, 2022
Grant date	Sep 13, 2022

Abstract

Modular surgical instruments and related methods are disclosed herein, e.g., for performing rod reduction, derotation, and/or set screw insertion during spinal surgery. An exemplary system can include an instrument body configured to couple to a bone anchor assembly to provide a modular platform for carrying out various steps of a surgical procedure. For example, the instrument body can receive a reduction instrument therethrough for reducing a spinal rod into the bone anchor assembly. A derotation instrument can be attached to the reduction instrument for performing derotation maneuvers or applying other manipulation forces. A modular driver or handle adapter can be attached to the reduction instrument and/or to the derotation instrument to facilitate rod reduction. Any of the instrument body, the reduction instrument, and the derotation instrument can include a working channel therethrough. A set screw or closure mechanism, and a driver instrument for applying the set screw or closure mechanism to the bone anchor assembly, can be inserted through the working channel.

First claim

The invention claimed is:

1. A surgical method, comprising:
implanting a bone anchor in a bone of a patient, the bone anchor comprising a receiver member having a rod seat;
positioning an instrument body in an unlocked configuration, the instrument body having a housing, opposed fixed arms extending distally from the housing and defining a rod slot therebetween, opposed pivoting arms movably coupled to the housing, a locking member, and a working channel extending through the instrument body, wherein the pivoting arms are free to pivot relative to the housing when the instrument body is in the unlocked configuration;
moving distal ends of the pivoting arms apart from one another;
positioning the bone anchor between the fixed arms of the instrument body such that the rod slot of the instrument body is aligned with the rod seat of the bone anchor;
moving the distal ends of the pivoting arms towards one another to engage a mating feature of the bone anchor; and
positioning the instrument body in a locked configuration by rotating the locking member relative to the instrument body to interfere with movement of the pivoting arms relative to the housing when the instrument body is in the locked configuration, thereby preventing the pivoting arms from disengaging from the mating feature of the bone anchor.

2. The method of claim 1 , further comprising placing a rod within the rod slot and advancing a reducer shaft through the working channel of the instrument body to urge the rod distally into the rod seat of the bone anchor.

3. The method of claim 2 , further comprising attaching a driver adapter to the reducer shaft and applying torque to the driver adapter to rotate the reducer shaft.

4. The method of claim 2 , further comprising inserting a set screw through a working channel of the reducer shaft and through the working channel of the instrument body and securing the set screw to the bone anchor.

5. The method of claim 4 , wherein urging the rod into the rod seat and a securing the set screw to the bone anchor are performed without disconnecting the instrument body from the bone anchor.

6. The method of claim 2 , further comprising attaching a derotation shaft to the reducer shaft and applying a manipulation force to the derotation shaft to reposition the bone of the patient.

7. The method of claim 6 , further comprising inserting a set screw through a working channel of the derotation shaft, through a working channel of the reducer shaft, and through the working channel of the instrument body, and securing the set screw to the bone anchor.

8. The method of claim 7 , wherein applying the manipulation force, urging the rod into the rod seat, and securing the set screw to the bone anchor are performed without disconnecting the instrument body from the bone anchor.

9. The method of claim 6 , wherein attaching the derotation shaft comprises inserting a male drive interface of the reducer shaft into a female drive interface of the derotation shaft.

10. The method of claim 6 , wherein attaching the derotation shaft comprises moving hinged arms of the derotation shaft into engagement with a groove formed in the reducer shaft.

11. The method of claim 10 , wherein the hinged arms are moved into engagement with the groove by rotating or axially translating a locking ring along an exterior surface of the derotation shaft.

12. The method of claim 6 , further comprising attaching a driver adapter to the derotation shaft and applying torque to the driver adapter to rotate the derotation shaft and the reducer shaft.

13. The method of claim 1 , wherein the bone anchor is implanted after attaching the instrument body to the bone anchor.

14. The method of claim 1 , wherein the bone anchor is implanted using a driver shaft inserted through the working channel of the instrument body while the instrument body is attached to the bone anchor.

15. The method of claim 1 , wherein the pivoting arms are free to pivot within a slot in the opposed fixed arms when the instrument body is in the unlocked configuration.

16. The method of claim 1 , wherein moving the distal ends of the pivoting arms towards one another increases a distance between the fixed arms and the pivoting arms.

17. The method of claim 1 , wherein moving the distal ends of the pivoting arms towards one another occurs after positioning the bone anchor between the fixed arms of the instrument body.

18. A surgical method, comprising:
docking an instrument body in an unlocked position to an implant such that the implant is received within a working channel that extends through the instrument body;
moving the instrument body into a locked position to mate the instrument body to the implant;
placing a rod within the working channel and reducing the rod into the implant using a reducer shaft received within the working channel of the instrument body, the reducer shaft having a working lumen formed therethrough;
inserting a set screw through the working channel and securing the set screw to the implant;
coupling a derotation assembly to the reducer shaft; and
derotating the reducer shaft to urge the rod toward the implant.

19. The method of claim 18 , wherein a central axis of the working channel of the instrument body is aligned with a central axis of the working lumen of the reducer shaft.

20. The method of claim 18 , wherein the set screw is inserted through one or more of the working lumen of the reducer shaft or a working lumen of the derotation assembly prior to securing the set screw to the implant.

21. The method of claim 18 , wherein the reducer shaft is disposed within the instrument body prior to the instrument body being docked to the implant.

22. The method of claim 18 , wherein docking the instrument body to the implant further comprises advancing the instrument body relative to the implant to pivot a pair of arms coupled to the instrument body in a radially-outward direction, and engaging a mating feature of the implant by moving the pair of arms in a radially-inward direction to mate the instrument body to the implant.

23. The method of claim 22 , wherein moving the instrument body into the locked position further comprises rotating a locking member relative to the instrument body in a first direction to prevent the pair of arms from pivoting relative to the implant.

24. The method of claim 23 , further comprising detaching the instrument body from the implant by rotating the locking member relative to the instrument body in a second, opposite direction to allow the pair of arms to freely pivot radially-outward with respect to the instrument body to disengage the implant.

25. The method of claim 18 , wherein the implant further comprises a receiver head of a bone anchor, with the bone anchor being implanted in a body of a patient.

26. The method of claim 18 , wherein advancing the rod through the working channel into the implant further comprises rotating the reducer shaft relative to the instrument body to urge the rod distally into the implant.

27. A surgical method, comprising:
implanting a bone anchor in a bone of a patient, the bone anchor comprising a receiver member having a rod seat;
positioning an instrument body in an unlocked configuration, the instrument body having a housing, opposed fixed arms extending distally from the housing and defining a rod slot therebetween, opposed pivoting arms movably coupled to the hous

Assignees

• Medos Int Sarl

Inventors

• Mickiewicz Christopher
• Gracia Mark
• Runco Thomas
• Batchelor Sarah
• Fournier Richard

Classifications

• A61B17/7082 Primary

  for driving, i.e. rotating, screws or screw parts specially adapted for spinal fixation, e.g. for driving polyaxial or tulip-headed screws · CPC title

• A61B17/0206

  with antagonistic arms as supports for retractor elements · CPC title

• A61B17/7032 Primary

  Screws or hooks with U-shaped head or back through which longitudinal rods pass · CPC title

• A61B17/7001

  Screws or hooks combined with longitudinal elements which do not contact vertebrae (A61B17/7058 takes precedence) · CPC title

• A61B2090/037

  with a frangible part, e.g. by reduced diameter · CPC title