Tibial plateau leveling osteotomy plate with suture holes

Abstract

Tibial plateau leveling osteotomy (TPLO) bone plates for use in four-legged animals including canines and felines are disclosed, with the bone plates having one or more suture holes configured for suturing muscle such as the pes anserinus muscle group to the TPLO bone plate. The one or more suture holes may be positioned on a leading edge of the bone plate and shaped so that the tails of a suture engaged with the suture hole are directed medially from the underlying fixed bone.

Description

TIBIAL PLATEAU LEVELING OSTEOTOMY PLATE WITH SUTURE HOLESCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application Serial No. 63 / 673,996, filed July 22, 2024, and entitled “TIBIAL PLATEAU LEVELING OSTEOTOMY PLATE WITH SUTURE HOLES,” which is hereby incorporated by reference herein in its entirety.BACKGROUNDField

[0002] The present disclosure relates to tibial plateau leveling osteotomy (TPLO) bone plates and procedures for canines and other four-legged animals.Related Art

[0003] Tibial plateau leveling osteotomies, in addition to other tibial osteotomies, are commonly performed in dogs, and occasionally in other animal species such as cats, to address rupture of the cranial cruciate ligament. Tibial plateau leveling osteotomy plates used in canines typically have an asymmetric shape with a relatively shorter upper portion and an elongated lower portion. Such bone plates commonly include multiple screw holes through which screws are inserted to fix the bone plate to the tibia.BRIEF SUMMARY

[0004] Aspects of the present technology provide bone plates for use for tibial plateau leveling osteotomy in non-human animals. The TPLO bone plate includes holes designed specifically to accommodate sutures to which the overlying musculature and fascia can be sutured. With such bone plates, TPLO procedures may include a step of suturing the pes anserinus to the bone plate after the bone plate is fixed to the tibia. Such procedures may provide for attachment of the pes anserinus in an anatomically correct location after fixation of the bone plate, thus promoting healing and post-operative function for the patient.

[0005] According to an aspect of the technology, a tibial plateau leveling osteotomy (TPLO) bone plate is provided, comprising: a TPLO bone plate body having an underside, an outer surface, a cranial edge, and a caudal edge. The TPLO bone plate comprises a first portion1355594.1of the TPLO bone plate body configured to be fixed to a lower portion of a tibia below an osteotomy and a second portion of the TPLO bone plate body configured to be fixed to an upper portion of the tibia above the osteotomy. The TPLO bone plate comprises a suture hole positioned in the first portion or second portion of the TPLO bone plate body proximate the cranial edge and configured to receive a suture attaching the pes anserinus to the TPLO bone plate.

[0006] According to an aspect of the present technology, a method of performing a tibial plateau leveling osteotomy (TPLO) on a patient is provided, comprising: creating an incision in a pes anserinus of the patient adjacent a tibia of the patient; cutting the tibia to form an upper portion and lower portion of the tibia separated by an osteotomy; fixing a TPLO bone plate to the tibia to stabilize the osteotomy; and suturing the pes anserinus to the TPLO bone plate by tying a suture to a suture hole in the TPLO bone plate proximate a cranial edge of the TPLO bone plate.BRIEF DESCRIPTION OF DRAWINGS

[0007] Various aspects and embodiments will be described with reference to the following exemplary and non-limiting figures. It should be appreciated that the figures are not necessarily drawn to scale. Items appearing in multiple figures are indicated by the same or a similar reference number in all the figures in which they appear.

[0008] FIG. 1 illustrates a tibial plateau leveling osteotomy (TPLO) stabilized with a 6- hole TPLO bone plate that includes only round holes both proximal and distal to the osteotomy.

[0009] FIG. 2 illustrates an alternative TPLO bone plate having suture holes for suturing overlying muscle and fascia, such as the pes anserinus, to the TPLO bone plate.

[0010] Fig. 3 illustrates a TPLO bone plate with suture holes that are at least partially recessed from the underside of the TPLO bone plate.

[0011] FIG. 4 illustrates a non-limiting example of placement of a TPLO bone plate of the types described herein on an underlying tibia together with a potential suturing pattern based on the suture holes of the TPLO bone plate.

[0012] FIGs. 5A-5C illustrate cross-sectional views taken along line 5A-5A of FIG. 4, with the addition of the overlying muscle being illustrated.

[0013] FIGs. 6 and 7 illustrate configurations of two different TPLO bone plates fixed to a tibia and having a line of suture holes for suturing overlying muscle and fascia to the TPLO bone plate.DETAILED DESCRIPTION

[0014] Aspects of the present technology provide bone plates for TPLO procedures in non-human animals, and particularly to bone plates having one or more suture holes configured to attach the overlying muscle and fascia, such as the pes anserinus, to the bone plate. TPLO procedures in non-human animals involve incising and retracting the pes anserinus, cutting the tibia to create an upper segment and lower segment, repositioning the upper segment relative to the lower segment, and fixing a bone plate to the two segments of the tibia. With the bone plate in place, reattaching the pes anserinus is difficult because the bone plate occupies the location at which the pes anserinus typically attaches to the tibia. Thus, in conventional canine TPLO procedures, the pes anserinus is either brought forward (cranially) from its natural anatomical position or is sutured directly to fascia or periosteum on the tibia. Both approaches are problematic. Both approaches face the challenge of having sufficient tissue to which to suture the pes anserinus and, since there often is insufficient tissue along the length of the incision, can result in gaps in the suturing, particularly in the vicinity of the tibial tuberosity. Sometimes, surgeons will suture the pes anserinus to the patellar tendon, which can cause patellar tendonitis and suboptimal post-surgical outcomes. The second approach of suturing the pes anserinus directly to the periosteum on the tibia is problematic because this tissue / periosteum is often limited in availability to hold suture and such reattachment can be weak or tenuous. Such suturing is prone to failure.

[0015] The inventor has recognized an improved approach, in which the pes anserinus is reattached to the bone plate. The bone plate comprises one or more suture holes configured for suturing the pes anserinus to the bone plate. The one or more suture holes are positioned on the bone plate to facilitate reattachment, for example being proximate a cranial edge of the bone plate, such as being on the cranio -proximal edge. Such positioning is consistent with the natural location of insertion of the pes anserinus, and thus provides beneficial anatomical positioning. Additionally, the one or more suture holes are shaped to facilitate the suture loop facing the underlying bone - the tibia - and the suture tails facing away from the underlying bone. When sutured, the pes anserinus sits on top of the bone plate such that the bone plate is between the bone - the tibia - and the pes anserinus. Thus, having the suture hole(s) shaped to accept a suture with the tails facing away from the bone facilitates proper suturing. In some embodiments, this means that the suture hole is recessed from the underside of the bone plate,facilitating passage of a suture needle through the suture hole and between the bone plate and the tibia.

[0016] FIG. 1 illustrates a TPLO bone plate having a plurality of suture holes configured to accommodate sutures for suturing overlying muscle and fascia, such as the pes anserinus, to the TPLO bone plate. The TPLO bone plate 100 comprises a body 102 having an underside 104, an outer surface 106, a cranial edge 108, and a caudal edge 110. The TPLO bone plate 100 comprises a plurality of screw holes 112 - six screw holes in this non-limiting example - and a plurality of suture holes 114. In this non-limiting example, each of the suture holes 114 includes two openings 116a and 116b. The TPLO bone plate 100 can be considered to have a first portion 118a and a second portion 118b, where the first portion 118a is configured to be fixed below the osteotomy in the tibia and the second portion 118b is configured to be fixed above the osteotomy in the tibia.

[0017] The TPLO bone plate is configured to be fixed to the tibia of a canine (or other four-legged animal) on an inner surface of the tibia, such that the cranial edge 108 is facing the patient’s head and the caudal edge 110 is facing the patient’s tail. The cranial edge 108 and caudal edge 110 may have any suitable thickness. For example, the cranial edge and caudal edge may have a thickness Tl. Tl may be sufficient to withstand forces upon the joined sections of the tibia. For example, the thickness Tl may be between 1.5 mm-4.5 mm in some embodiments, and most commonly between 2 mm and 3.5 mm. However, it should be appreciated that the cranial edge 108 and caudal edge 110 may not have the same thickness, and may not have uniform thicknesses. Moreover, in some embodiments the cranial edge 108 and / or caudal edge 110 may be rounded, or may not be distinct edges of the TPLO bone plate.

[0018] As shown, the TPLO bone plate 100 comprises a plurality of screw holes 112. The screw holes 112 may be of any suitable type, including round screw holes, oval screw holes, and figure-8 (or “snowman”) screw holes. Moreover, the screw holes 112 may be locking or non-locking screw holes. Any suitable number of screw holes may be provided, as the various aspects of the technology described herein are not limited in this respect unless otherwise stated.

[0019] As described above, the TPLO bone plate 100 comprises a plurality of suture holes 114. The suture holes 114 are configured to facilitate suturing of overlying tissue (e.g., muscle and fascia) to the TPLO bone plate 100. The suture holes in at least some embodiments are suitable for suturing the pes anserinus to the TPLO bone plate 100. The suture holes 114 are positioned appropriately, being positioned along the cranial edge 108 of the TPLO bone plate, which in some embodiments is a proximal and cranial edge, near where an incision in and elevation of the pes anserinus from the tibia is typically made during a TPLO procedure.Moreover, in the illustrated example, the suture holes 114 are positioned near the cranial edge 108 on the second portion 118b of the TPLO bone plate, where, once the TPLO bone plate is fixed to the tibia, typically there is little substantive tissue to which the pes anserinus can be reattached. Thus, in at least some embodiments, the suture hole(s) may be along the cranial edge of the bone plate. In some embodiments, the suture holes span the entire length of the cranial edge of bone plate. In alternative embodiments, the holes are focused in the cranioproximal regions of the bone plate.

[0020] Any suitable number of suture holes may be provided. The number of suture holes may range from 1 to 20 but in at least some embodiments the TPLO bone plates described herein have between 2 and 10 sutures holes.

[0021] The suture holes are sufficiently large to accommodate standard suture needles for suture ranging in size from 1 to size 000. However, the suture holes need not be larger than that in some embodiments.

[0022] The suture holes in at least some embodiments will have smooth edges (e.g., rounded edges, beveled edges, or other smooth edges) so that the suture is not cut by sharp edges. Moreover, as illustrated in FIG. 3 and described further below in connection with that figure, the suture holes may be at least partially recessed from the underside of the TPLO bone plate to facilitate passage of a suture needle through the suture hole when the plate is fixed to the tibia with the underside of the bone plate against the tibia. In some embodiments, as shown, the suture holes exit on the cranial edge of the TPLO bone plate at openings 116a. such positioning of the openings 116a may facilitate passage of a suture needle 120 attached to the suture 122.

[0023] The suture holes, which can be thought of as tunnels for the suture needle and suture to pass through, in at least some embodiments may be oriented roughly perpendicular to the cranial edge of the bone plate (see FIG. 5A). However, in some embodiments the holes may be angled up to 10 degrees in either direction from perpendicular to the outer surface 106.

[0024] In the example of FIG. 1, the first portion 118a and second portion 118b of the TPLO bone plate 100 are asymmetrical. The first portion 118a is elongated with a single role of screw holes, while the second portion 118b is shorter and more rounded in shape, and includes a first row of two screw holes configured to be positioned proximate to the osteotomy.

[0025] FIG. 2 illustrates an alternative TPLO bone plate have suture holes for suturing overlying muscle and fascia, such as the pes anserinus, to the TPLO bone plate. The TPLO bone plate 200 comprises a body 202 having an underside 204, an outer surface 206, a cranial edge 208, and a caudal edge 210. The TPLO bone plate 200 comprises a plurality of screw holes 212 - six screw holes in this non-limiting example - and a plurality of suture holes 214.In this non-limiting example, each of the suture holes 214 includes two openings 216a and 216b. The TPLO bone plate 200 can be considered to have a first portion 218a and a second portion 218b, where the first portion 218a is configured to be fixed below the osteotomy in the tibia and the second portion 218b is configured to be fixed above the osteotomy in the tibia.

[0026] The TPLO bone plate 200 differs from the TPLO bone plate 100 in that the bone plate is shaped differently and has a different number and position of suture holes. The TPLO bone plate 200 is shorter than the TPLO bone plate 100 and first portion 218a is shaped substantially similarly to the second portion 218b. Each of the first potion 218a and second portion 218b has a first row of multiple screw holes configured to be positioned proximate the osteotomy. The TPLO bone plate 200 includes suture holes 214 positioned on both the first portion 218a and the second portion 218b. Such placement of suture holes 214 may facilitate suturing a greater length of the pes anserinus to the bone plate compared to that afforded by the TPLO bone plate 100 of FIG. 1. The suture holes 214 in both the first portion 218a and second portion 218b are shown as being positioned proximate the cranial edge 208 of the bone plate.

[0027] As described above, in some embodiments the TPLO bone plates with suture holes described herein include suture holes that are at least partially recessed from the underside of the TPLO bone plate. Such a configuration facilitates passing a suture needle through the suture hole and between the bone plate and the underlying bone. FIG. 3 illustrates a nonlimiting example. The TPEO bone plate 300 is substantially the same as the TPEO bone plate 100 of FIG. 1 and therefore not all reference characters from FIG. 1 are repeated in FIG. 3. The differences are that the TPEO bone plate 300 comprises a different number of suture holes - two suture holes as opposed to five - and that the suture holes of the TPEO bone plate 300 differ in that they are recessed from the underside of the TPEO bone plate as described further below. The other features of the TPEO bone plate 300 are the same as that of TPEO bone plate 100 and therefore are not described again in detail here. The reader is directed to the description of features in FIG. 1 for additional detail.

[0028] The TPLO bone plate 300 comprises two suture holes 302 configured to allow for suturing of overlying muscle and fascia, such as the pes anserinus, to the TPLO bone plate. Each suture hole 302 comprises a recessed edge 304 instead of an opening 116a in the cranial edge of the TPLO bone plate. The recessed edge 304 permits the passage of a suture needle 120 between the underside of the TPLO bone plate 300 and the bone to which it is affixed. As shown, the recessed edge 304 may have a curved shape, and may be rounded to reduce the chance of damage to the suture 122. Such a recessed edge 304 may form part of the opening of the suture hole 304, with a remaining portion of the opening on the underside of the TPLO boneplate 300. While FIG. 3 is the only figure illustrating suture holes 302 of that shape, it should be appreciated that any of the other TPLO bone plates illustrated and described herein may alternatively have suture holes shaped like that in FIG. 3.

[0029] FIG. 4 illustrates a non-limiting example of placement of a TPLO bone plate of the types described herein on an underlying tibia together with a potential suturing pattern based on the suture holes of the TPLO bone plate. The tibia in FIG. 4 is shown without osteotomy for purposes of simplicity. The system 400 includes TPLO bone plate 402 which is substantially the same as TPLO bone plate 100 of FIG. 1 except that it comprises a greater number of suture holes. Otherwise, the TPLO bone plate 402 is the same as TPLO bone plate 100 and therefore is not described in detail again here. The reader is directed to the description of features in FIG. 1 for additional detail.

[0030] The system 400 includes the TPLO bone plate 402 positioned on the tibia 404, a femur 406, patella 408, and patellar tendon 410. The TPLO bone plate 402 comprises a plurality of suture holes 412 having openings on the exterior surface and cranial edge of the TPLO bone plate 400. The suture holes 412 accommodate a plurality of sutures 414. The dashed line 416 represents a line of incision in the muscle and fascia. As can be seen, the suture holes 414 are positioned at approximately the location of the incision, and therefore use of the suture holes 414 to reattach the muscle and fascia allows for proper anatomical placement of the muscle and fascia after the TPLO bone plate 400 is fixed. In the non-limiting example of FIG. 4, the TPLO bone plate 400 does not have suture holes on its lower portion, and therefore reattachment of the muscle and facia proximate the lower portion of the TPLO bone plate 400 may include reattaching the muscle and fascia to tissue along dashed line 418.

[0031] FIGs. 5A-5C illustrate cross-sectional views taken along line 5A-5A of FIG. 4, with the addition of the overlying muscle being illustrated. That is, FIG. 5A shows muscle 502 overlying TPLO bone plate 402 and being sutured with suture 122 through suture hole 412. FIGs. 5A and 5B illustrate the suture needle 120 being passed through the suture hole 412 and brought back to make a loop, with the completed loop 504 shown in FIG. 5C. As also shown in FIG. 5C, the loop 504 faces the underside of the TPLO bone plate 402 and the tibia 404, while the tails 506 of the suture loop face away from the tibia 404. Such a configuration of the suture hole 412 facilitates suturing the overlying muscle 502 to the TPLO bone plate 402. It should also be noted that after the leading edge of the suture is passed through the suture hole (412 in Figure 5A), the suture could be passed through the leading edge of the muscle / fascia a second time before the loop of suture is completed. In such application the suture will have traversed the muscle / fascia layer two times or, more generally, multiple times.

[0032] FIGs. 6 and 7 illustrate configurations of two different TPLO bone plates fixed to a tibia and having a line of suture holes for suturing overlying muscle and fascia to the TPLO bone plate. FIG. 6 illustrates one example, in which the TPLO bone plate 600 comprises six screw holes including two snowman- shaped screw holes 603 and four round screw holes 605. The TPLO bone plate 600 comprises a first portion coupled to a lower segment 604a of the tibia below the osteotomy 607 and a second portion coupled to an upper segment 604b of the tibia above the osteotomy 607. A plurality of sutures 608 are placed adjacent the cranial edge of the TPLO bone plate 600 in corresponding suture holes of the types described previously herein.

[0033] FIG. 7 illustrates an alternative bone plate 700. The TPLO bone plate 700 is shorter than the TPLO bone plate 600, lacking the elongated first portion below the osteotomy 607. Instead, the portion of the TPLO bone plate 700 below the osteotomy 607 is more similarly shaped to the portion of the TPLO bone plate 700 above the osteotomy.

[0034] The various embodiments described herein provide various benefits, some of which have been described above and some of which are now listed. It should be appreciated that not all embodiments provide all listed benefits, and that benefits other than those listed may be realized in some embodiments. TPLO bone plates of the types described herein facilitate reattachment of muscle and fascia, such as the pes anserinus, to the TPLO bone plate in an anatomically appropriate location. This facilitates suturing / stabilization of these muscles, making it easier than by conventional approaches, will avoid the need to suture these muscles to the patella tendon, and will ensure the TPLO plate is covered by the appropriately placed / stabilized muscles.

[0035] According to some embodiments, the TPLO bone plate further comprises a fenestration window, or a plurality of fenestration windows, configured to be positioned over the osteotomy.

[0036] The TPLO bone plates described herein may be used for stabilization of other fractures or osteotomies in veterinary patients including fractures of the proximal tibia and distal femoral osteotomies or fractures.

[0037] Various aspects of the present disclosure may be used alone, in combination, or in a variety of arrangements not specifically described in the embodiments described in the foregoing and is therefore not limited in its disclosure to the details and arrangement of components set forth in the foregoing description or illustrated in the drawings. For example, aspects described in one embodiment may be combined in any manner with aspects described in other embodiments.

[0038] The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.”

[0039] The phrase “and / or,” as used herein in the specification and in the claims, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with “and / or” should be construed in the same fashion, i.e., “one or more” of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the “and / or” clause, whether related or unrelated to those elements specifically identified.

[0040] As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified.

[0041] Use of ordinal terms such as “first,” “second,” “third,” etc., in the claims to modify a claim element does not by itself connote any priority, precedence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements.

[0042] The terms “approximately” and “about” may be used to mean within ±20% of a target value in some embodiments, within ±10% of a target value in some embodiments, within ±5% of a target value in some embodiments, and yet within ±2% of a target value in some embodiments. The terms “approximately” and “about” may include the target value.

[0043] Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having,” “containing,” “involving,” and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.

[0044] It should also be noted that the pes anserinus is a general term used to describe a grouping of muscles that insert / attaches in the region of the proximal medial tibia. Such muscles can include, but are not limited to, the sartorius muscle, the semitendinosus, gracilis, and associated fascia. Reference to the pes anserinus in this document can refer to any of thesemuscles alone or in combination or the associated fascial attachments of the aforementioned muscles to the tibia.

[0045] Having described above several aspects of at least one embodiment, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be object of this disclosure. Accordingly, the foregoing description and drawings are by way of example only.

Claims

CLAIMSWhat is claimed is:

1. A tibial plateau leveling osteotomy (TPLO) bone plate, comprising: a TPLO bone plate body having an underside, an outer surface, a cranial edge, and a caudal edge, a first portion of the TPLO bone plate body configured to be fixed to a lower portion of a tibia below an osteotomy; a second portion of the TPLO bone plate body configured to be fixed to an upper portion of the tibia above the osteotomy; and a suture hole positioned in the first portion or second portion of the TPLO bone plate body proximate the cranial edge and configured to receive a suture attaching the pes anserinus to the TPLO bone plate.

2. The TPLO bone plate of claim 1, wherein the suture hole includes an opening in the cranial edge of the TPLO bone plate body.

3. The TPLO bone plate of claim 1, wherein the suture hole has an edge at least partially recessed from the underside of the TPLO bone plate body.

4. The TPLO bone plate of claim 3, wherein the suture hole is recessed from the underside of the TPLO bone plate body at the cranial edge.

5. The TPLO bone plate of claim 1, wherein the TPLO bone plate comprises a plurality of suture holes configured to receive respective sutures attaching the pes anserinus to the TPLO bone plate, wherein the suture hole is a first suture hole of the plurality of suture holes.

6. The TPLO bone plate of claim 1, wherein the first portion has a length between 7 mm and 4 cm and has a first row of multiple screw holes proximate the osteotomy.

7. A method of performing a tibial plateau leveling osteotomy (TPLO) on a patient, comprising: creating an incision in a pes anserinus of the patient adjacent a tibia of the patient;cutting the tibia to form an upper portion and lower portion of the tibia separated by an osteotomy; fixing a TPLO bone plate to the tibia to stabilize the osteotomy; and suturing the pes anserinus to the TPLO bone plate by tying a suture to a suture hole in the TPLO bone plate proximate a cranial edge of the TPLO bone plate.

8. The method of claim 7, wherein the TPLO bone plate comprises a plurality of suture holes proximate the cranial edge, and wherein the method further comprises suturing the pes anserinus to the TPLO bone plate by tying a plurality of sutures to the TPLO bone plate proximate the cranial edge of the TPLO bone plate using the plurality of suture holes.

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