US-20260127737-A1 - PERIPHERAL SCREW LENGTH DETERMINATION

Abstract

Systems, methods, and devices are disclosed comprising a computer-assisted surgical system for an implant that is configured to be affixed by a plurality of peripheral screws to a bone of a patient. The computer-assisted surgical system comprising an instrument and a navigation array attached to the instrument, the instrument for cutting the bone, a tracking system to detect and track elements of the navigation array, a display, and a controller having at least one processor configured to receive an image of the bone for receiving the implant, receive instrument positional data from the tracking system to determine a trajectory of the instrument, generate, on the display, a representation of a distal end of the instrument overlaid over the image, generate, on the display, a representation of a scale along the trajectory of the instrument overlaid over the image, wherein the scale includes graduations related to a length of a peripheral screw along the trajectory, and wherein the scale graduations are independent of the position of the distal end of the instrument, and update at least one of the representations as the instrument moves.

Inventors

• Nicolas DEMANGET
• Alexander Samaha
• Cory Emil
• Cyprien Adnet

Assignees

• DePuy Synthes Products, Inc.

Dates

Publication Date

20260507

Application Date

20241106

Claims (20)

1. 1 . A computer-assisted surgical system for an implant that is configured to be affixed by a plurality of peripheral screws to a bone of a patient, comprising: an instrument and a navigation array attached to the instrument, the instrument for cutting the bone; a tracking system to detect and track elements of the navigation array; a display; and a controller having at least one processor configured to: receive an image of the bone for receiving the implant; receive instrument positional data from the tracking system to determine a trajectory of the instrument; generate, on the display, a representation of a distal end of the instrument overlaid over the image; generate, on the display, a representation of a scale having a same trajectory as the trajectory of the instrument, at least a portion of the representation of the scale extending past the representation of the distal end of the instrument, the representation of the scale being overlaid over the image, wherein the scale includes graduations related to a length of a peripheral screw along the scale trajectory, and wherein an initial graduation of the scale is independent of the position of the distal end of the instrument; and update at least one of the representations as the instrument moves.
2. 2 . The system of claim 1 , wherein the image is a 2D slice of a 3D volume.
3. 3 . The system of claim 1 , wherein the controller is further configured to receive a position of the bone for receiving the implant.
4. 4 . The system of claim 1 , wherein the controller is further configured to receive information about the implant.
5. 5 . The system of claim 4 , wherein the controller is further configured to determine theoretical points of the center of rotation of peripheral screws when the peripheral screws are fully seated in the implant.
6. 6 . The system of claim 5 , wherein the controller is further configured to determine a derived plane of the implant based on the theoretical points.
7. 7 . The system of claim 6 , wherein the controller is further configured to generate the representation of the scale using the derived plane as the initial graduation of the scale.
8. 8 . The system of claim 7 , wherein graduations of the scale represent units of distance.
9. 9 . The system of claim 7 , wherein graduations of the scale represent predetermined peripheral screw sizes.
10. 10 . The system of claim 2 , wherein the controller is further configured to generate the representations such that if the distal end of the instrument is moved along the scale, the same image is used, but if the trajectory of the instrument is changed, the representations are overlaid over a different 2D slice of the 3D volume.
11. 11 . The system of claim 1 , wherein the controller is further configured to generate, on the display, a representation of the implant overlaid over the image.
12. 12 . The system of claim 1 , wherein the controller is further configured to suggest a peripheral screw length.
13. 13 . The system of claim 12 , wherein the controller is further configured to determine at least one of a torque for the instrument or a time of operation for the instrument, and to use the determined torque or the determined time to determine a best fit peripheral screw length.
14. 14 . The system of claim 1 , wherein if the position and orientation of the implant is known, the controller is further configured to use this information to determine a derived plane of the implant and to use the derived plane as the initial graduation of the scale.
15. 15 . The system of claim 1 , wherein the controller is further configured to determine a torque of the instrument and associate the determined torque with a type of bone.
16. 16 . The system of claim 15 , wherein the controller is further configured to determine a position of the associated bone type and use the position of the associated bone type as the initial graduation of the scale.
17. 17 . The system of claim 1 , wherein the controller is further configured to determine a current of the instrument and associate the determined torque with a type of bone.
18. 18 . The system of claim 17 , wherein the controller is further configured to determine a position of the associated bone type and use the position of the associated bone type as the initial graduation of the scale.
19. 19 . The system of claim 1 , wherein the controller is further configured to suggest an appropriate peripheral screw based on one or more of a bone type, instrument position, or instrument work.
20. 20 . The system of claim 1 , wherein the controller is further configured to display the scale as free to move in space until a determination is made by the controller that the drill bit is in position, and then the controller is further configured to display the initial graduation of the scale as locked in position while allowing the representation of the scale to pivot.

Description

BACKGROUND Many orthopedic surgeries involve implant systems. For example, shoulder arthroplasties may require replacing an articulation surface in a joint. In this example, a baseplate (such as a glenoid reconstruction reverse baseplate) is secured to bone by a plurality of peripheral screws. Peripheral screws are important for both strong fixation and anti-rotation of the baseplate. Peripheral screws come in a number of predetermined lengths. As may be appreciated, a surgeon performing such a procedure may desire to select a trajectory that will maximize fixation and/or a peripheral screw length that is sufficiently long yet avoids compromising the bone into which the peripheral screw will be placed (e.g., to avoid a peripheral screw that is too long). Baseplate depth, inclination, retroversion, and position of openings for receiving the peripheral screws all may be known but given that a drill trajectory occurs in three-dimensions, determination of clinically desirable peripheral screw length (and thus depth into the bone) from two-dimensional images (even where a plurality of views are present) is difficult. Moreover, making an informed decision about peripheral screw length relative to its final seating in the baseplate can be challenging when merely viewing imaging. Accordingly, there is a need for determining peripheral screw trajectory (e.g., from an opening in the baseplate for receiving the peripheral screw to a distal end of the bore) and/or desirable peripheral screw length. It is also desirable to provide a graphical user interface that renders visualization of screw length more intuitive. SUMMARY Systems, methods, and devices are disclosed comprising computer-assisted surgical systems for an implant that is configured to be affixed by a plurality of peripheral screws to a bone of a patient. The computer-assisted surgical systems may comprise an instrument and a navigation array attached to the instrument, the instrument for cutting the bone, a tracking system to detect and track elements of the navigation array, a display, and a controller having at least one processor configured to receive an image of the bone for receiving the implant, receive instrument positional data from the tracking system to determine a trajectory of the instrument, generate, on the display, a representation of a distal end of the instrument overlaid over the image (e.g., the image may be a 2D slice of a 3D volume), generate, on the display, a representation of a scale along the trajectory of the instrument overlaid over the image, wherein the scale includes graduations related to a length of a peripheral screw along the trajectory, and wherein the scale graduations are independent of the position of the distal end of the instrument, and update at least one of the representations as the instrument moves. In some embodiments, the controller is further configured to receive a position of the bone for receiving the implant. For example, a second navigation array may be attached to the patient, and the tracking system used to detect and track elements of the second navigation array to determine the position of the bone. As will be described, a controller may overlay a representation of a scale and/or the scale and a drill position (e.g., as an overlay image) over an image of the patient to allow a user (e.g., surgeon) to determine a clinically desirable peripheral screw length. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A shows a schematic of a glenoid reconstruction reverse baseplate with superimposed theoretical points for centers of rotation for the peripheral screws according to an embodiment of the present application. FIG. 1B shows a schematic of a section of the glenoid reconstruction baseplate of FIG. 1A where the superimposed theoretical points for centers of rotation are fully seated in the baseplate and have been used to derive a plane relative to a coordinate system of the baseplate. FIG. 2A shows an exemplary display comprising representations of the baseplate, the derived plane, a scale, and a drill overlaid over a patient image. FIG. 2B shows another exemplary display comprising representations of the baseplate, the derived plane, a scale, and a drill overlaid over another patient image. FIG. 2C shows another exemplary display comprising representations of the baseplate, the derived plane, the scale, and the drill overlaid over a patient image, wherein the drill depth has changed as compared to FIG. 2A. FIG. 2D shows another exemplary display comprising representations of a scale and a drill overlaid over a pair of patient images. FIG. 3 shows a flowchart of a method of determining the derived plane. FIG. 4 shows a flowchart of a method of generating the representation of the scale. FIG. 5A shows another exemplary display comprising representations of the baseplate, a scale, and the drill overlaid over a patient image. FIG. 5B shows another exemplary display comprising representations of the baseplate, the scal