Navigated force sensing instruments

Patent metadata

Field	Value
Publication number	US-12440282-B2
Application number	US-202318300630-A
Country	US
Kind code	B2
Filing date	Apr 14, 2023
Priority date	Apr 14, 2023
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

Navigated force sensing instrument, systems, and methods. The navigated force sensing instruments may be used for applying forces to correct the spine, for example, in compression, distraction, reduction, and/or derotation. The trackable instrument includes markers viewable and trackable by a navigation system, including rigid and movable markers. The trackable instrument includes a flexible portion located between the rigid and movable markers. When a surgical task is performed, the markers indicate the amount of force applied to the instrument and/or a stiffness of the spine.

First claim

What is claimed is:

1. A method for correcting a spinal deformity comprising the steps of:
providing a trackable instrument for correcting a spinal deformity comprising:
a body having a distal portion configured to perform a surgical task and a proximal portion configured to be manipulated by a user,
a plurality of markers configured to be tracked by a navigation system including a rigid marker and a movable marker attached to the body;
a flexible portion located along the body, wherein the flexible portion is positioned between the rigid marker and the movable marker, and

positioning the trackable instrument on a portion of a spine having the spinal deformity; and
performing a surgical task, wherein the plurality of markers indicate an amount of force applied to the instrument.

2. The method of claim 1 , wherein the instrument is further configured to characterize a stiffness of a spine by measuring navigated displacements of the spine resulting from applied forces by the instrument.

3. The method of claim 1 , wherein the surgical task is compression, distraction, reduction, and/or derotation of a spine.

4. The method of claim 1 , wherein the flexible portion has a known stiffness, relative motion of the movable marker relative to the rigid marker results from the known stiffness of the flexible portion, and the relative motion is measurable by the navigation system.

5. The method of claim 1 , wherein the flexible portion includes one or more relief cuts, a reduced segment having a reduced width, or a flexible material section.

6. The method of claim 1 , wherein the flexible portion includes one or more relief cuts having linear or helical cuts.

7. The method of claim 1 , wherein the flexible portion includes linear relief cuts, a decreased width, and a helical cut, thereby resulting in decreased stiffnesses in different directions due to varying orientations of removed material.

8. A method for correcting a spinal deformity comprising the steps of:
providing a surgical system comprising:
a navigation system including an infrared signal based position recognition system; and
a trackable instrument having a plurality of markers viewable and trackable by the navigation system, the plurality of markers including a rigid marker and a movable marker attached to the instrument, the trackable instrument includes a flexible portion having a known stiffness, wherein the flexible portion is located between the rigid marker and the movable marker, and wherein relative motion of the movable marker relative to the rigid marker results from the stiffness of the flexible portion, and the relative motion is measurable by the navigation system

performing a surgical task using the surgical system to correct the spinal deformity.

9. The method of claim 8 , wherein the trackable instrument is a compressor, distractor, reducer, or derotator.

10. The method of claim 8 , wherein the trackable instrument is a compressor or distractor having a first pivoting arm and an opposed second pivoting arm interconnected at a center pivot pin, the first and second pivoting arms each define a handle, the flexible portion is defined in one of the handles above the pivot pin, the rigid marker is affixed to a rigid segment of the first or second pivoting arm, and the movable marker is affixed to one handle on an opposite side of the flexible portion.

11. The method of claim 10 , wherein a first rigid marker is attached to the first pivoting arm below the center pivot pin, a second rigid marker is attached to the second pivoting arm above the center pivot pin on one side of the instrument, and the movable marker is attached to the handle via a lever arm on an opposite side of the instrument.

12. The method of claim 8 , wherein the trackable instrument is a rod link reducer having a manipulator arm and a handle, the flexible portion is defined into the manipulator arm, a proximal array including the movable marker is located proximally and a distal array including a rigid marker is located distally along the manipulator arm, and the flexible portion separates the distal array from the proximal array.

13. The method of claim 8 , wherein the trackable instrument is a rib pusher having a body handle defining a hollow interior, a plunger having a piston received in one end of the body handle, and a spring located inside the body handle, the rigid marker is located on the body handle, and the movable marker is located on the plunger.

14. The method of claim 8 , wherein the trackable instrument is a reducer having a body, a pair of engagement tabs attached to the body, and a central pusher threaded through the body, the rigid marker is located on the body, and the movable marker is located on the engagement tab.

15. The method of claim 14 , wherein each engagement tab has a proximal section and a distal section that terminates at a free end configured to engage a screw head, the engagement tab is attached to the body at a connecting portion adjacent to a flexure, and when tension is applied to the engagement tab during reduction or derotation, the proximal section acts as an extended moment arm, and extends off of the flexure to magnify displacement of the movable marker.

16. A method of correcting a spinal deformity comprising:
applying a force to a spine with a trackable instrument, the trackable instrument having a plurality of markers viewable and trackable by a navigation system, the plurality of markers including a rigid marker and a movable marker attached to the instrument, the trackable instrument includes a flexible portion located between the rigid marker and the movable marker, the flexible portion including one or more relief cuts, a reduced segment having a reduced width, or a flexible material section; and
monitoring movement of the rigid and movable markers to determine the force applied to the instrument.

17. The method of claim 16 , further comprising determining a stiffness of the spine along a single motion or multi-motion spine segment.

18. The method of claim 17 , further comprising applying force and torque to the spine segment to adjust an angle and displacement of the spine segment.

19. The method of claim 16 , wherein the force includes applying torque in three directions, and the movable marker is configured to measure the applied torques at varying resolutions and magnitudes based on the amount of torque applied in each direction.

20. The method of claim 16 , further comprising attaching navigated screw extenders to bone fasteners installed in vertebrae, and monitoring the screw extenders to determine movement of the vertebrae.

Assignees

• Globus Medical Inc

Inventors

• Murray Patrick
• Leff David
• Hill Albert
• LaColla John
• Muralidharan Shruthi
• Nichols Jeff
• Soltanianzadeh Amir

Classifications

• A61B90/06

  Measuring instruments not otherwise provided for · CPC title

• A61B2090/397

  electromagnetic other than visible, e.g. microwave · CPC title

• A61B2090/064

  for measuring force, pressure or mechanical tension · CPC title

• A61B2034/2051

  Electromagnetic tracking systems · CPC title

• A61B17/7074

  Tools specially adapted for spinal fixation operations other than for bone removal or filler handling (A61B17/7062, A61B17/808, A61B17/8858 take precedence; for spinal image producing devices A61B90/36, A61B34/20; markers A61B90/39) · CPC title