# Patent

## Title
Method and apparatus for locking a drill guide in a polyaxial hole

## Abstract

Devices, systems, and methods for locking a drill guide into a polyaxial hole while maintaining the form and function of the polyaxial hole are provided herein. In some embodiments, the drill guide includes a hollow outer body extending from a proximal end to a distal end and having a slot disposed proximate the proximate end, wherein the distal end is configured as a reverse collet having a plurality of prongs; an inner body having a central channel extending therethrough; and a lever coupled to the inner body through the slot, wherein the slot is shaped such that rotation of the lever results in motion along a central axis of the drill guide, and wherein a distal end of the inner body is configured to prevent radially inward deflection of the plurality of prongs when the inner body is in a lowermost position.

## Background
RELATED APPLICATIONS
This application is a continuation application of U.S. application Ser. No. 16/373,676 filed on Apr. 3, 2019 (published as U.S. Pat. Pub. No. 2019-0314042), which claims priority to U.S. Provisional Patent Application No. 62/655,934, filed Apr. 11, 2018, the contents of which are hereby incorporated by reference in its entirety.


FIELD
The present disclosure relates to surgical devices, and more particularly, stabilization systems, for example, for trauma applications.
BACKGROUND
Bone fractures are often repaired by internal fixation of the bone, such as diaphyseal bone, using one or more plates. The plate is held against the fractured bone with screws, for example, which engage the bone and heads which provide a compressive force against the plate. The plate and bone are thus forced against each other in a manner that transfers load primarily between a bone contacting surface of the plate and the bone surface to reinforce the fractured bone during healing. This manner of plating generally creates relatively low stress concentration in the bone, as there may be a large contact area between the plate and the diaphyseal bone surface permitting transfer of load to be dispersed. There may be a desire to use locking screws, non-locking screws, or a combination of both that are able to compress the bone. Of course, the designs of the plates, types of screws, and locking and/or non-locking capabilities may vary based on the location and type of fracture.
In some cases, plates having polyaxial holes may be used to provide increased flexibility with regards to screw orientation. However, with such polyaxial holes, locking of the screw may be difficult. As such, features may be included in the holes to provide surfaces against which the screw can lock. However, there is a need for a method for aligning a drill bit to the nominal axis of a polyaxial hole and locking the drill guide in such a hole without compromising the structure of the hole. Such a hole cannot be threaded into via a threaded drill guide because doing so would jeopardize the locking capabilities of the polyaxial hole.
SUMMARY
To meet this and other needs, devices, systems, and methods for locking a drill guide into a polyaxial hole while maintaining the form and function of the polyaxial hole are provided herein. In some embodiments, the drill guide includes a hollow outer body extending from a proximal end to a distal end and having a slot disposed proximate the proximate end, wherein the distal end is configured as a reverse collet having a plurality of prongs; an inner body having a central channel extending therethrough; and a lever coupled to the inner body through the slot, wherein the slot is shaped such that rotation of the lever results in motion along a central axis of the drill guide, and wherein a distal end of the inner body is configured to prevent radially inward deflection of the plurality of prongs when the inner body is in a lowermost position.
In some embodiments, a method of locking a drill guide in a hole includes inserting the drill guide into the hole; pushing the distal end of the outer body beyond a shoulder of the hole, wherein the shoulder pushes the plurality of prongs radially inwardly upon contact, and wherein the plurality of prongs return to a resting position after the distal end is pushed beyond the shoulder; and rotating the lever to move the inner body to a lowermost position in which a distal end of the inner body is disposed between the plurality of prongs to prevent radially inward deflection of the plurality of prongs.
In some embodiments, a drill guide includes a hollow outer body extending from a proximal end to a distal end and having a slot disposed proximate the proximal end, wherein the distal end is configured as a reverse collet having a plurality of prongs; an inner body having a central channel extending therethrough; a spring disposed within the hollow outer body and beneath a portion of the inner body, wherein the spring biases the inner body in a direction away from the plurality of prongs; a cap coupled to the proximal end of the hollow outer body and having a through hole disposed through an upper portion of the cap in communication with the central channel, wherein the through hole is configured to allow passage of a drill bit into the central channel; a handle coupled to the hollow outer body to allow a user to grip the drill guide; and a lever coupled to the inner body through the slot, wherein the slot is shaped such that rotation of the lever results in motion along a central axis of the drill guide, and wherein a distal end of the inner body is configured to prevent radially inward deflection of the plurality of prongs when the inner body is in a lowermost position.



BRIEF DESCRIPTION OF THE DRAWING
A more complete understanding of the present invention, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:
FIG. 1A depicts an isometric view of a plate having a polyaxial hole with which a drill guide in accordance with at least some embodiments of the present invention may be utilized.
FIG. 1B depicts a cross-sectional view of the plate of FIG. 1A taken along line B-B′.
FIG. 2 depicts an isometric view of a drill guide in accordance with at least some embodiments of the present invention.
FIG. 3 depicts a cross-sectional view of the drill guide of FIG. 2 taken along line 3-3′.
FIG. 4 depicts a close-up cross-sectional view of a drill guide inserted into a polyaxial hole in accordance with at least some embodiments of the present invention.
FIG. 5 depicts a perspective view of a drill guide used to introduce a plate into a surgical field and as a drill guide in accordance with some embodiments of the present invention.
FIG. 6 depicts a side perspective view of a drill guide used as a k-wire guide in accordance with some embodiments of the present disclosure.
FIG. 7 depicts an isometric view of a drill guide in accordance with at least some embodiments of the present invention.



DETAILED DESCRIPTION
Embodiments of the disclosure are generally directed to devices, systems, and methods for aligning and locking a drill guide into a polyaxial hole while maintaining the form and function of the polyaxial hole. Specifically, embodiments are directed to a drill guide configured to align a drill bit with a nominal axis/trajectory of a polyaxial screw hole. The inventive drill guide may be used with bone plates with locking and/or non-locking fasteners for dynamic compression of the bone. The hole designs may allow for polyaxial locking of the fasteners. The inventive drill guide advantageously provides for one-handed operation with quick and reliable locking capabilities. The inventive drill guide is also ergonomic and its design is streamlined.
The plates may be adapted to contact one or more of a femur, a distal tibia, a proximal tibia, a proximal humerus, a distal humerus, a clavicle, a fibula, an ulna, a radius, bones of the foot, bones of the hand, or other suitable bone or bones. The bone plate may be curved, contoured, straight, or flat. The plate may have a head portion that is contoured to match a particular bone surface, such as a metaphysis or diaphysis, flares out from the shaft portion, forms an L-shape, T-shape, Y-shape, etc., with the shaft portion, or that forms any other appropriate shape to fit the anatomy of the bone to be treated.
The embodiments of the disclosure and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments and examples that are described and/or illustrated in the accompanying drawings and detailed in the following description. The features of one embodiment may be employed with other embodiments as the skilled artisan would recognize, even if not explicitly stated herein. Descriptions of well-known components and processing techniques may be omitted so as to not unnecessarily obscure the embodiments of the disclosure. The examples used herein are intended merely to facilitate an understanding of ways in which the disclosure may be practiced and to further enable those of skill in the art to practice the embodiments of the disclosure. Accordingly, the examples and embodiments herein should not be construed as limiting the scope of the disclosure, which is defined solely by the appended claims and applicable law. Moreover, it is noted that like reference numerals represent similar features and structures throughout the several views of the drawings.
Referring now to the drawings, FIGS. 1A and 1B depict an isometric view and a cross-sectional view, respectively, of a plate 10 including at least one opening such as, for example, a polyaxial hole 12. The polyaxial hole 12 extends through the plate 10 is configured to accept a locking fastener (not shown) that is able to dynamically compress the bone and/or affix the plate 10 to the bone.
As shown more clearly in FIG. 1B, the polyaxial hole 12 may have one or more locking features designed to engage with the locking fastener such as, for example, wind-swept cuts 14 discreetly patterned in two directions. The polyaxial hole geometry may be used in bone plates 10 to utilize polyaxial locking screws that can achieve dynamic compression. Although only one polyaxial hole 12 is shown, the plate 10 may comprise any suitable number of polyaxial holes 12 in any suitable configuration.
The polyaxial hole 12 cannot be threaded into via a threaded drill guide because doing so would jeopardize the locking capabilities of the polyaxial hole 12. That is, threading into the polyaxial hole 12 would damage the wind-swept cuts 14, thus negatively impacting the locking capabilities of the polyaxial hole 12. As such, the inventors have discovered an improved drill guide 200 that overcomes the need to thread into a polyaxial hole.
Referring to FIGS. 2-4, the drill guide 200 extends from a proximal end 202 to a distal end 204 and includes an outer body 206 and an inner body 302 (shown in FIG. 3) disposed within and concentric with the outer body 206. The outer body 206 is substantially hollow and houses the inner body 302. A cap 208 may be disposed and locked onto the proximal end 204 of the outer body 206 and includes a through hole 210 disposed through an upper portion of the cap 210. The through hole 210 is configured to allow the passage of a drill bit (not shown) to extend into the interior of the drill guide 200. In some embodiments, the drill guide 200 may further include a handle 216 coupled to the outer body 206. The handle 216 may include one or more holes 218 to facilitate placement of additional tools such as, for example, a guide wire. In some embodiments, the handle 216 is fixedly coupled to the outer body 206. In some embodiments, the handle 216 is alternatively removably coupled to the outer body 206.
As depicted in FIG. 3, the inner body 302 is tubular an includes a central channel 304 extending along a central axis 306 of the drill guide 200. The inner body 302 is configured to receive a drill bit extending through the central channel 304 and to align the drill bit with the central axis 103 of the hole 102. In embodiments in which it is desirable for the screw (not shown) extending through the hole 102 to not be aligned with the central axis 103 of the hole 102, the drill guide 200 may alternatively be configured to align the drill bit with a different trajectory (i.e., the central axis 306 is aligned with the desired orientation of the screw to be utilized in the hole 102).
As shown more clearly in FIG. 4, the distal end 204 of the drill guide 200 may be configured as a reverse collet 402 so that when the drill guide 200 is pushed into the hole 102, a plurality of prongs 402A,B,C (only A and B shown in cross-section of FIG. 4) of the reverse collet 402 are forced radially inwardly (opposite the direction of arrows C) by the shape of the hole 102 (e.g., a shoulder 106). Subsequently, when the drill guide 200 is pushed further into the hole 102, the prongs 402A,B,C return to their original position, as depicted in FIG. 4. It should be noted that although the description of the reverse collet 402 includes three prongs, the reverse collet may alternative include fewer or more prongs.
Referring now to FIGS. 2-4, in some embodiments, the drill guide 200 may include a lever 212 a distal end of which is coupled to the inner body 302 through a slot 214 formed in the outer body 206. The slot 214 is shaped such that when the lever 212 is turned in a predetermined direction (indicated by arrow D), the inner body 302 is moved downwards, as indicated by arrow A in FIG. 4. The downward motion of the inner body 302 moves a distal end 404 of the inner body 302 into an area between the prongs 402A,B,C, thus forcing the prongs 402A,B,C radially outwardly, as indicated by arrows C, which prevents the prongs from retracting radially inwardly. As a result, the drill guide 200 becomes locked in the hole 102. Thus, a rigid locking of the drill guide 200 is provided which also advantageously avoids damage of the screw locking features of the hole 102. The rigid locking also ensures that the drill guide 200 remains properly aligned with the desired screw trajectory to ensure drilling always occurs at the correct orientation. It should be noted that use of a lever to move the inner body 302 is only exemplary and any means of moving the inner body downwardly to lock the drill guide 200 is contemplated.
In some embodiments, the drill guide 200 may include a spring 308 to bias the inner body 302 upwardly, such that the turning of the lever 212 to lower the inner body 302 acts against a bias of the spring 308. In some embodiments, the handle 216 may include a graphic 220 to indicate in which direction movement of the lever will lock and unlock the drill guide 200 in the hole.
In some embodiments, the rigid locking provided by the drill guide 200 may advantageously also allow for the use of the drill guide 200 to introduce a device (e.g., a fixation plate) into a surgical area, as shown, for example, in FIG. 5. In the example shown in FIG. 5, the drill guide 200 is locked into a hole (not visible) of a plate 502. The drill guide may be used to transport and position the plate 502 at a surgical site such as, for example, a bone 504. After the plate 502 is positioned as desired, the drill bit 506 of a drill 508 may be inserted into the drill guide 200 to drill a hole into the bone 504. In addition, a guide wire 510 may also be inserted into the plate 504 to guide a screw (not shown) into the bone 504.
As shown in FIG. 6, in some embodiments, the drill guide 200 may also be used to insert a k-wire 602 for provisional fixation.
FIG. 7 depicts an embodiment of a drill guide 700 in accordance with embodiments of the present disclosure. The drill guide 700 is substantially similar to the drill guide 200 described above. In some embodiments, the drill guide 700 includes a handle 716 that is similar to the handle 216 described above except that the handle 716 has an improved ergonomic design configured to fit the general contours of a user's hand. In some embodiments, the drill guide 700 may also include a lever 712 that functions similarly to the lever 212. In this embodiment, the lever 712 may have a spherical shape for improved grasping by a user.
Although the invention has been described in detail and with reference to specific embodiments, it will be apparent to one skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. Thus, it is intended that the invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. It is expressly intended, for example, that all ranges broadly recited in this document include within their scope all narrower ranges which fall within the broader ranges. It is also intended that the components of the various devices disclosed above may be combined or modified in any suitable configuration.

## Claims

1. A drill guide, comprising:
an outer body extending from a proximal end to a distal end and having a slot disposed proximate the proximal end;
an inner body disposed in the outer body;
a lever coupled to the inner body through the slot, wherein rotation of the lever to a first position of the lever translates the inner body towards the distal end of the outer body to lock the outer body to a bone plate, and when the lever is in a second position the outer body may be removed from the bone plate; and
a spring disposed within the outer body and beneath a portion of the inner body, wherein the spring biases the inner body in a direction away from the distal end of the outer body.

2. The drill guide of claim 1, further comprising:
a handle coupled to the outer body to allow a user to grip the drill guide.

3. The drill guide of claim 2, wherein the handle includes one or more holes configured to facilitate placement of a tool through the one or more holes.

4. The drill guide of claim 2, wherein the handle is fixedly coupled to the outer body.

5. The drill guide of claim 2, wherein the handle is removably coupled to the outer body.

6. The drill guide of claim 1, wherein a plurality of prongs disposed on the distal end of the outer body are configured to deflect radially inwardly when the prongs are inserted into a hole of the bone plate.

7. The drill guide of claim 1, wherein the lever has a spherical shape.

8. The drill guide of claim 1, further comprising:
a cap coupled to the proximal end of the outer body and having a through hole disposed through an upper portion of the cap in communication with the inner body, wherein the through hole is configured to allow passage of a drill bit into the inner body.

9. A method of locking a drill guide in a hole, comprising:
inserting the drill guide into the hole, wherein the drill guide comprises:
an outer body extending from a proximal end to a distal end and having a slot disposed proximate the proximal end;
an inner body disposed in the outer body; and


a lever coupled to the inner body through the slot, wherein rotation of the lever to a first position of the lever translates the inner body towards the distal end of the outer body to lock the outer body to a bone plate, and when the lever is in a second position the outer body may be removed from the bone plate,
pushing the distal end of the outer body beyond a shoulder of the hole, wherein the shoulder pushes the distal end radially inwardly upon contact, and wherein the distal end returns to a resting position after the distal end is pushed beyond the shoulder; and
rotating the lever to move the inner body to a lowermost position in which a distal end of the inner body is disposed in the distal end of the outer body to prevent radially inward deflection of the distal end of the outer body.

10. The method of claim 9, wherein the drill guide further comprises:
a spring disposed within the outer body and beneath a portion of the inner body, wherein the spring biases the inner body in a direction away from the distal end of the outer body.

11. The method of claim 9, wherein the drill guide further comprises:
a handle coupled to the outer body to allow a user to grip the drill guide.

12. The method of claim 11, wherein the handle includes one or more holes configured to facilitate placement of a tool through the one or more holes.

13. The method of claim 11, wherein the handle is fixedly coupled to the outer body.

14. The method of claim 11, wherein the handle is removably coupled to the outer body.

15. The method of claim 9, wherein the distal end of the outer body is a plurality of prongs configured to deflect radially inwardly when the prongs are inserted into the hole.

16. The method of claim 9, wherein the lever has a spherical shape.

17. The method of claim 9, wherein the drill guide further comprises:
a cap coupled to the proximal end of the outer body and having a through hole disposed through an upper portion of the cap in communication with the inner body, wherein the through hole is configured to allow passage of a drill bit into the central channel.

18. A system for treating a bone fracture, comprising:
a bone plate including at least one polyaxial hole;
a drill guide, wherein the drill includes:
an outer body extending from a proximal end to a distal end and having a slot disposed proximate the proximal end;
an inner body disposed in the outer body; and
a lever coupled to the inner body through the slot, wherein rotation of the lever to a first position of the lever translates the inner body towards the distal end of the outer body to lock the outer body to the bone plate, and when the lever is in a second position the outer body may be removed from the bone plate;


a spring disposed within the outer body and beneath a portion of the inner body, wherein the spring biases the inner body in a direction away from the distal end of the outer body;
a cap coupled to the proximal end of the outer body and having a through hole disposed through an upper portion of the cap in communication with the inner body, wherein the through hole is configured to allow passage of a drill bit into the inner body;
a handle coupled to the outer body to allow a user to grip the drill guide.

19. System for treating a bone fracture of claim 18, wherein the lever has a spherical shape.