Implant for focal talus defects and method

Abstract

There is provided a kit for inserting a talar implant. The kit comprises at least one tibial guide; a talar implant. The kit comprises a body section comprising an exposed, smooth continuous top surface; a mesh section extending down from the body section; and at least one solid prong extending down from the body section through the mesh section, the at least one solid prong comprising a spike end. The body section, the mesh section and the at least one solid prong are printed as one piece; at least one talar guide having a U- shape shaped body comprising a first end, a second end and a distal region spaced opposite the first and second ends. The distal region comprises a hole extending therethrough from the top side to the bone engaging bottom side that is configured to receive a first pin inserted therethrough and into a talus bone when the bone engaging bottom side is positioned on the talus bone. The kit includes at least one impactor instrument for inserting the talar implant into a patient's talus; and a reamer comprising a handle and a cutting head configured to form a portion of the talus bone that approximates the talar implant. The cutting head comprises a hole extending therethrough that is configured to receive the first pin such that the cutting head can be slid down the pin and cut the talus bone in a guided manner. 20 25 20 01 31 09 J an 2 02 5 A B S T R A C T 2 0 2 5 2 0 0 1 3 1 0 9 J a n 2 0 2 5

Description

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] The present application is a divisional application from Australian Patent Application No. 2021329641, the entire disclosure of which is incorporated herein by reference. This application also claims priority from U.S. provisional application No. 63 / 068,425, fded August 21, 2020, which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present invention relates generally to general, podiatric, and orthopaedic surgery related to the repair of focal defects in a bone. More specifically, but not exclusively, the present invention relates to focal defects in a talus of an ankle joint. BACKGROUND OF THE INVENTION

[0003] At least one embodiment of the invention relates to an implant used to repair a focal talus defect and a method for inserting this implant into a focal talus defect. The talus bone is positioned in the lower part of an ankle joint. It can bear the weight of an individual as the weight of the individual is transmitted from the person's leg to their foot. Portions or all of a talus bone can become compromised by disease or injury. Therefore, there is a need for an implant for a talus bone, in particular there is a need for a focal talus or talar implant and a method for efficiently implanting this implant into a patient's talus.

[0004] A reference herein to a patent document or any other matter identified as prior art, is not to be taken as an admission that the document or other matter was known or that the information it contains was part of the common general knowledge as at the priority date of any of the claims. SUMMARY

[0005] There is disclosed herein a talar implant having at least one body section, at least one mesh section and at least one solid section extending down from the body section, with the solid section having at least one point or spike.

[0006] In at least one embodiment there is a kit for inserting a talar implant including at least one tibial guide, a talar implant, comprising: a body section comprising an exposed, smooth continuous top surface; a mesh section extending down from the body section; and at least one solid prong extending down from the 2025200131   09 Jan 2025 body section through the mesh section, the at least one solid prong comprising a spike end, wherein the body section, the mesh section and the at least one solid prong are printed as one piece; at least one talar guide having a U-shape shaped body comprising a first end, a second end and a distal region spaced opposite the first and second ends, wherein the distal region comprises a hole extending therethrough from the top side to the bone engaging bottom side that is configured to receive a first pin inserted therethrough and into a talus bone when the bone engaging bottom side is positioned on the talus bone; at least one impactor for inserting the talar implant into a patient's talus; and a reamer comprising a handle and a cutting head configured to form a portion of the talus bone that approximates the talar implant, wherein the cutting head comprises a hole extending therethrough that is configured to receive the first pin such that the cutting head can be slid down the pin and cut the talus bone in a guided manner.

[0007] In addition, there is also a method for implanting a talus implant that may include identifying a damaged boney area, projecting a missing damaged area on a contralateral joint and then printing an implant based upon a mirror image of a normal portion of the contralateral joint. The method may also include using at least one guide, removing at least a portion of a damaged region of the talus and then inserting the talar implant and setting the talar implant. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the detailed description herein, serve to explain the principles of the invention. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. The drawings are only for purposes of illustrating preferred embodiments and are not to be construed as limiting the invention. FIG. 1A is a top perspective view of an implant implanted into a talus, in accordance with an aspect of the present invention; FIG. IB is a top view of the implant of FIG. 1 implanted into the talus, in accordance with an aspect of the present invention; FIG. 2 A is a side perspective view of the implant of FIG. 1 positioned above the talus prior to implantation, in accordance with an aspect of the present invention; 2025200131   09 Jan 2025 FIG. 2B is a side view of the implant of FIG. 1, in accordance with an aspect of the present invention; FIG. 2C is a top view of the implant of FIG. 1, in accordance with an aspect of the present invention; FIG. 2D is a top perspective view of the implant of FIG. 1, in accordance with an aspect of the present invention; FIG. 3 is a medial view of the ankle joint with the talus implant of FIG. 1 implanted into the talus bone, in accordance with an aspect of the present invention; FIG. 4A is a side perspective view of an impactor instrument for implanting an focal talar implant, in accordance with an aspect of the present invention; FIG. 4B is another side perspective view of the impactor instrument of FIG. 4A, in accordance with an aspect of the present invention; FIG. 4C is a side perspective view of the impactor instrument of FIG. 4A, in accordance with an aspect of the present invention; FIG. 4D is a side view of the impactor instrument of FIG. 4A, in accordance with an aspect of the present invention; FIG. 4E is another side view of the impactor instrument of FIG. 4A, in accordance with an aspect of the present invention; FIG. 4F is a perspective view of the impactor instrument of FIG. A, in accordance with an aspect of the present invention; FIG. 5A is a side view of a reamer, in accordance with an aspect of the present invention; FIG. 5B is a side perspective view of the reamer of FIG. 5 A, in accordance with an aspect of the present invention; FIG. 5C is a side view of the reamer of FIG. 5 A, in accordance with an aspect of the present invention; FIG. 5D is a front perspective view of the reamer of FIG. 5 A, in accordance with an aspect of the present invention; FIG. 5E is an end side view of the reamer of FIG. 5 A, in accordance with an aspect of the present invention; FIG. 6A is a perspective view of a custom tibial guide, in accordance with an aspect of the present invention; FIG. 6B is a side perspective view of the custom tibial guide of FIG. 6A, in accordance with an aspect of the present invention; 2025200131   09 Jan 2025 FIG. 6C is a perspective top view of the custom tibial guide of FIG. 6A, in accordance with an aspect of the present invention; FIG. 6D is a top view of the custom tibial guide of FIG. 6A, in accordance with an aspect of the present invention; FIG. 7A is a side view of a custom talar guide, in accordance with an aspect of the present invention; FIG. 7B is a bottom side of the custom talar guide of FIG. 7A, in accordance with an aspect of the present invention; FIG. 7C is a top perspective view of the custom talar guide of FIG. 7A , in accordance with an aspect of the present invention; FIG. 7D is a side view of the custom talar guide of FIG. 7A, in accordance with an aspect of the present invention; FIG. 8A is a perspective view of a custom reamer, in accordance with an aspect of the present invention; FIG. 8B is a top view of the custom reamer of FIG. 8A, in accordance with an aspect of the present invention; FIG. 9A is a perspective view an ankle joint showing a step for inserting an implant in a talus, in accordance with an aspect of the present invention; FIG. 9B is a perspective view an ankle joint showing another step for inserting an implant in a talus, in accordance with an aspect of the present invention; FIG. 9C is a side view of an ankle joint showing another step for inserting an implant in a talus, in accordance with an aspect of the present invention; FIG. 9D is an anterior view of an ankle joint showing another step for inserting an implant in a talus, in accordance with an aspect of the present invention; FIG. 9E is side view of an ankle joint showing another step for inserting an implant in a talus, in accordance with an aspect of the present invention; FIG. 9F is a side view oof an ankle joint showing another step for inserting an implant in a talus, in accordance with an aspect of the present invention; and FIG. 10 is a flow chart for the method of fabricating and implanting the implant in the talus. 2025200131   09 Jan 2025 DETAILED DESCRIPTION FOR CARRYING OUT THE INVENTION

[0009] Generally stated, disclosed herein are guides, implants, devices, instruments, systems, and assemblies for achieving bone fusion. Further, methods for using the guides, implants, devices, instruments, systems, and assemblies to repair bone defects are discussed.

[0010] In this detailed description and the following claims, the words proximal, distal, anterior or plantar, posterior or dorsal, medial, lateral, superior and inferior are defined by their standard usage for indicating a particular part or portion of a bone or implant according to the relative disposition of the natural bone or directional terms of reference. For example, “proximal” means the portion of a device or implant nearest the torso, while “distal” indicates the portion of the device or implant farthest from the torso. As for directional terms, “anterior” is a direction towards the front side of the body, “posterior” means a direction towards the back side of the body, “medial” means towards the midline of the body, “lateral” is a direction towards the sides or away from the midline of the body, “superior” means a direction above and “inferior” means a direction below another object or structure. Further, specifically in regards to the foot, the term “dorsal” refers to the top of the foot and the term “plantar” refers the bottom of the foot.

[0011] Similarly, positions or directions may be used herein with reference to anatomical structures or surfaces. For example, as the current implants, devices, instrumentation and methods are described herein with reference to use with the bones of the foot, the bones of the foot, ankle and lower leg may be used to describe the surfaces, positions, directions or orientations of the implants, devices, instrumentation and methods. Further, the implants, devices, instrumentation and methods, and the aspects, components, features and the like thereof, disclosed herein are described with respect to one side of the body for brevity purposes. However, as the human body is relatively symmetrical or mirrored about a line of symmetry (midline), it is hereby expressly contemplated that the implants, devices, instrumentation and methods, and the aspects, components, features and the like thereof, described and / or illustrated herein may be changed, varied, modified, reconfigured or otherwise altered for use or association with another side of the body for a same or similar purpose without departing from the spirit and scope of the invention. For example, the implants, devices, instrumentation and methods, and the aspects, components, features and the like thereof, described herein with respect to the right foot may be mirrored so that they likewise function with the left foot. Further, the implants, devices, instrumentation and methods, and the aspects, components, features and the like thereof, disclosed herein are described with respect to the foot for brevity purposes, but it should be understood that the 2025200131   09 Jan 2025 implants, devices, instrumentation and methods may be used with other bones of the body having similar structures.

[0012] Referring to the drawings, wherein like reference numerals are used to indicate like or analogous components throughout the several views, and with particular reference to FIG. 1A is a top side perspective view of the inventive implant 20 implanted into a talus.

[0013] FIG. IB is a top view of the implant 20 implanted into the talus bone 11. For example, there is shown an implant body 20 implanted around an open rim of a talus bone 11. The talus bone includes a body 17, a neck 16 which leads to a head 13 and a process 14. This feature is shown in FIG. 1A as well.

[0014] FIG. 2A is a side perspective view of the implant 20 positioned above the talus, wherein the talus implant 20 includes a mesh region 22 having a patterned mesh that can be for example in the form of a honeycomb pattern of varying porosity or alternatively, of a standard or uniform porosity. A plurality of solid prongs such as prongs 26 and 28 (See FIG. 2B) extend out from implant 20 through the mesh and towards a spike end. Theimplant 20 is configured to be printed such as through 3D printing with the top surface 24 of implant 20 being further coated with a shiny or resilient coat 24 (See FIGS. 2C and 2D).

[0015] FIG. 3 is a side view of the ankle joint with the talus implant 20 implanted into the talus bone. For example, there is shown the talus 11 having the implant 20 positioned therein. A tibia bone 30 is positioned superior to the talus implant 20 and the talus bone 11. In addition, as shown, the neck of the talus 16 extends into a head 13 which then extends into contact with the navicular bone 19.

[0016] FIGS. 4A-4F show various views of an impactor instrument for implanting the implant 20. The impactor 50 is configured as a tool for inserting the implant 20 into the talus 11. For example, the impactor 50 includes a body section 52, a first end 54 and a second end 56 (See FIGS. 4B, 40 and 4F). The second end 56 is a cup shape (or concave bowl shape) configured to accept the head or surface of the implant 20. FIGS. 4C, 4D, 4E and 4F are 2-D wireframe depictions of the impactor 50 from various perspectives.

[0017] FIGS. 5A-5E show different views of a bone cutting reamer. For example, the reamer is configured to carve out a section of the talus 11 to facilitate the implantation of the implant 20. The reamer 60 includes a handle 62, having indents 63. The handle has a smooth or continuous section 64 that is proximate and extends to a 2025200131   09 Jan 2025 cutting head 68 This handle extends to a head 68. The head 68 is configured to be a frusto-conical shape so that it can be extended into the talus 11 to create an opening that facilitate the implantation of the implant 20. The head also includes an open channel 66 which extends substantially longitudinally along the handle 62. This open channel 66 allows for the withdrawal of material or fluid from the talus 11 when it is being actuated.

[0018] FIG. 6A is a perspective view of a custom tibial cutting guide 70 for which the tibial guide 70 includes a body section 71 with wings 75 and 77 with an extension section 72 having holes 73.1 and 73.2. There is also aprotrusion 76 having holes 78 and 79. In addition, a slot 74 extends along the width of the tibial cutting guide through which a saw blade may be placed.

[0019] FIG. 6B is a side perspective view of the tibial cutting guide 70 and more clearly shows the body section 71 having the protrusion 76 with the holes 78 and 79 extending down in a cylindrical manner. In addition, FIG. 6B shows the wings 75 and 77. The cutting slot 74 is shown to extend from a first side shown in FIG. 6A to the second side shown in FIG. 6B (see also FIGS. 6C and 6D as well). The tibial cutting guide 70 is configured to be attached in close proximity to the tibia to allow a medical practitioner to slice or remove a portionof a patient's tibia through a knife or other cutting mechanism operating through the slot 74.

[0020] FIG. 7A is a side view of a custom talar cutting guide 80, which includes holes 82, 83 and 84 disposed in a U-shaped body 81. These holes 82, 83, and 84 extend in a cylindrical manner to form slots for receiving pins which are insertable into these holes and which are insertable into a corresponding talus implant.

[0021] FIG. 7B shows the bottom side for the talar cutting guide 80. The surface of the bottom side is configured to be placed on top of the talus 11 prior to a reaming step. Accordingly, the opposite facing top side of the talar cutting guide 80 which has holes 82, 83 and 84 which are configured to receive pins is shown in FIG. 7C. The body 81 of the talar cutting guide is shaped as a substantially U- shape or horseshoe shape having a first end 86 and a hole 84, a second end 85 having a hole 83 and a distal region 87 spaced opposite the ends 85 and 86. FIG. 7D is a side view of the custom talar cutting guide 80 which includes holes 82, 83 and 84. Hole 82 is positioned in the distal region 87 of the body 81.

[0022] FIG. 8A is a perspective view of a custom bone cutting reamer 90 which is positioned in talus 11 and configured to remove bone from a region of the talus 11 by 2025200131   09 Jan 2025 using a head 99, and a shaft 92 which is integrally attached to the head 99. The head 99 has a plurality of teeth 98 as well as a central hole 96. The central hole 96 (See FIG. 8B) can be used to slide over a guide pin which can be set by the talus guide. (See FIG. 7B).

[0023] FIGS. 9A-9F show the method for preparing and implanting the talus implant 20 into a patient. FIG. 10 further shows as a flow chart the example steps for the fabrication and implantation method for the implant 20 into the talus 11. For example, the method process may start at S1 during which the health care professional may identify the most damaged area of the talus 11. Once the damaged area is identified either through surgery or through an X-ray, MRI or CT scan, the extent of the damage of this region is assessed. The health care professional may expand the area that the implant 20 will replace beyond the damaged area by a pre-set amount. The method at S2 may include the health care professional projecting the missing or damaged area based upon a mirror view or image or projection of an undamaged contralateral talus. Next, at S3, the implant 20 may be printed, followed for example by S4, where the health care professional may remove damaged bone from the tibia by using a cutting instrument. This is shown at FIGS. 9A and 9B. It should be noted that S4 and S5 may be interchanged depending on the preference of the health care professional.

[0024] The health care professional may then apply the tibial guide 70 as shown in FIG. 9A and 9B S4, wherein the tibial guide can be inserted on to the tibia 30. Pins 110, 111, 112 and 113 are inserted into the respective holes 73.1 and 73.2 as well as holes 78 and 79. With the pins being inserted into these holes the tibial guide 70 is fixed to the tibia 30. The fixing of the tibial guide 70 allows for the extension of the slot 74 (See FIG. 6D) across the tibia 30 which allows for the cutting of the tibia S5 to expose the talus to the heath care professional.

[0025] The method may include the application of the talar guide 80 by the health care professional S6 on to the talus 11 as shown in FIG. 9C. This is accomplished by placing the talar guide 80 having the surface 89 (See FIG. 7B) on the talus 11 and then inserting pins or rods such as pins 101, 103, and 105 through respective holes 82, 83, 84 (See FIG. 7C). The application of the talar guide 80 can be used to set a pin such as pin 105 which inserts through hole 82 on the talar guide 80 to fix the location of the guide 80 for the insertion of the reamer 60, 90 as listed at S7 of FIG. 10.

[0026] Next, as shown in FIGS. 9D and 9E and in FIG. 10, S8, the reamer 60, 90 is positioned to be inserted into the talus 11. Specifically, reamer 60 has a substantially 2025200131   09 Jan 2025 frusto conical shaped head which closely approximates the implant 20, is inserted into the talus to remove the damaged bone and allow for the insertion of the implant 20. The reamer also includes the central hole 66, 96 which can be slid down on the pin 105 to then remove the damaged bone in a guided manner.

[0027] Once the damaged bone has been removed, at S9, the implant 20 can then be inserted with an impactor 50 to set the implant 20 into the talus. (See FIG. 9F and S9, 10 in FIG. 10). The impactor 50 has a concave face 56 that eliminates any damage to the domed surface of the implant 20. After the implant has been implanted, the procedure may be completed and the patient’s incision may be closed.

[0028] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprise” (and any form of comprise, such as “comprises” and “comprising”), “have” (and any form of have, such as “has”, and “having”), “include” (and any form of include, such as “includes” and “including”), and “contain” (and any form of contain, such as “contains” and “containing”) are open-ended linking verbs. As a result, a method or device that “comprises,” “has,” “includes,” or “contains” one or more steps or elements possesses those one or more steps or elements, but is not limited to possessing only those one or more steps or elements. Likewise, a step of a method or an element of a device that “comprises,” “has,” “includes,” or “contains” one or more features possesses those one or more features, but is not limited to possessing only those one or more features. Furthermore, a device or structure that is configured in a certain way is configured in at least that way, but may also be configured in ways that are not listed.

[0029] The invention has been described with reference to the preferred embodiments. It will be understood that the architectural and operational embodiments described herein are exemplary of a plurality of possible arrangements to provide the same general features, characteristics, and general system operation. Modifications and alterations will occur to others upon a reading and understanding of the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations.

Claims

1. A kit for inserting a talar implant comprising:at least one tibial guide;a talar implant, comprising:a body section comprising an exposed, smooth continuous top surface;a mesh section extending down from the body section; andat least one solid prong extending down from the body section through the mesh section, the at least one solid prong comprising a spike end, wherein the body section, the mesh section and the at least one solid prong are printed as one piece;at least one talar guide having a U- shape shaped body comprising a first end, a second end and a distal region spaced opposite the first and second ends, wherein the distal region comprises a hole extending therethrough from the top side to the bone engaging bottom side that is configured to receive a first pin inserted therethrough and into a talus bone when the bone engaging bottom side is positioned on the talus bone;at least one impactor instrument for inserting the talar implant into a patient's talus; anda reamer comprising a handle and a cutting head configured to form a portion of the talus bone that approximates the talar implant, wherein the cutting head comprises a hole extending therethrough that is configured to receive the first pin such that the cutting head can be slid down the pin and cut the talus bone in a guided manner.

2. The kit of claim 1, wherein the at least one tibial guide has at least one slotconfigured to accept a cutting tool to cut a tibia in a guided manner along the slot.

3. The kit of claim 1 or 2, wherein the first and second ends of the at least one talar guide each comprise a f hole extending therethrough from the top side to the bone engaging bottom side that is configured to receive a pin inserted therethrough and into respective portions of the talus bone when the bone engaging bottom side is positioned on the talus bone.

4. The kit of claim 3, wherein the holes of the first and second ends of the at least2025200131   09 Jan 2025one talar guide extend through protrusions extending from a top side of the body.

5. The kit of any one of claims 1 to 4, wherein the impactor has a first end and a second end, wherein the first end is configured as a substantially concave surface.

6. The kit of any one of claims 1 to 5, wherein the body section of the talar implant is semi-spherical.

7. The kit of any one of claims 1 to 6, wherein the mesh section of the talar implant isconfigured as a honeycomb pattern comprising a plurality of cells.

8. The kit of any one of claims 1 to 7, wherein the mesh section of the talar implant has a variable porosity.

9. The kit of any one of claims 1 to 8, wherein the at least one solid prong comprises a plurality of prongs extending down from the body section through the mesh section.

10. The kit of any one of claims 1 to 9, wherein the top surface of the body section of the talar implant has a shiny or resilient coating.

11. The kit of any one of claims 1 to 10, wherein the top surface of the body section of the talar implant is a domed shaped.

12. The kit of claim 11, wherein the at least one impactor comprises a concave end face configured to engage with the domed shaped top surface of the talar implant.

13. The kit of any one of claims 1 to 12, wherein the cutting head of the reamer is frusto-conical shaped.

14. The kit of any one of claims 1 to 13, wherein the hole of the distal region of the at least one talar guide extends through a protrusion extending from a top side of the body.

15. A method for implanting a talus implant comprising:obtaining the kit of any one of claims 1 to 14;applying the at least one talar guide to a talus bone such that the bone engaging bottom side is positioned on the talus bone;inserting a first pin through the hole of the distal region of the body of the at least one2025200131   09 Jan 2025talar guide and into the talus bone;removing at least a portion of a damaged region of the talus bone via the inserted first pin and the reamer;inserting the talar implant into the talus bone; andsetting the talar implant within the talus bone via the at least one impactor instrument.

16. The method of claim 15, wherein the removing at least a portion of a damaged region of the talus bone comprises sliding the cutting head over the inserted first pin via the hole extending through the cutting head.

17. The method of claim 15 or 16, further comprising removing a portion of a tibia bone that is adjacent to the talus bone via the at least one tibia guide.

18. The method of any one of claims 15 to 17, further comprising inserting a pin through each of the first and second ends of the body of the at least one talar guide and into the talus bone.

19. The method of any one of claims 15 to 18, further comprising:identifying the damaged area of the talus bone;projecting a missing damaged area on a talus bone of a contralateral joint; and printing the talus implant based upon a mirror image of a portion of the talus bone of the contralateral j oint.

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