Variable angle locking fasteners and methods of repair

Abstract

This disclosure relates to variable angle locking fasteners for securing orthopaedic components at a surgical site. The fasteners may include various features for establishing fixation with the component and / or for facilitating insertion of the fastener at various orientations to secure the component at the surgical site.

Description

VARIABLE ANGLE LOCKING FASTENERS AND METHODSOF REPAIRCROSS-REFERENCE TO RELATED APPLICATIONS[oooi] This application claims priority to United States Patent Application No. 63 / 547,157, filed November 3, 2023, the disclosure of which is incorporated herein by reference in its entirety.BACKGROUND

[0002] This disclosure relates to orthopaedic procedures and, more particularly, to orthopaedic implant systems and methods for restoring functionality to bones and joints.

[0003] Adjacent bones and / or adjacent portions of the same bone may require fixation due to trauma or to correct various deficiencies in the bone or joint. A bone plate may be utilized to provide fixation. The bone plate may include one or more holes dimensioned to receive respective fasteners for securing the bone plate. The fastener may be a variable angle locking screw that may be inserted at various orientations in the bone.SUMMARY

[0004] This disclosure relates to improved orthopaedic systems and methods of performing a surgical procedure. The system may include one or more variable angle locking fasteners that may be adapted to engage apertures of various orthopaedic components to bone and / or other tissue at the surgical site. The fasteners may include various features to improve fixation between the fastener and component and insertion of the fastener at various orientations.[ooos] A variable angle locking fastener for orthopaedic procedures disclosed herein may include a fastener body extending along a fastener axis between a proximal end and a distal end. The fastener body may include a shank portion, a head portion, and a neck portion interconnecting the shank portion and the head portion. The shank portion may include at least one fixation thread dimensioned to engage bone. The head portion may include at least one locking thread extending about the fastener axis to establish a conical periphery of the head portion. The conical periphery may bedimensioned to engage an aperture of an orthopaedic component. A proximal chamfer may extend between the conical periphery and the proximal end.

[0006] A variable angle locking fastener for orthopaedic procedures disclosed herein may include a fastener body extending along a fastener axis between a proximal end and a distal end. The fastener body may include a shank portion, a head portion, and a neck portion interconnecting the shank portion and the head portion. The shank portion may include at least one fixation thread dimensioned to engage bone. The head portion may include at least one locking thread extending about the fastener axis to establish a conical periphery of the head portion. The conical periphery may be dimensioned to engage an aperture of an orthopaedic component. At least one cutting flute in the periphery may include a cutting surface dimensioned to engage bone. A flute profde of the at least one cutting flute may be dimensioned to interrupt neighboring thread segments of the at least one locking thread.

[0007] An orthopaedic system for orthopaedic procedures disclosed herein may include a bone plate including a plate body dimensioned to abut bone and an aperture extending through the plate body. A variable angle locking fastener may include a fastener body including a shank portion, a head portion, and a neck portion interconnecting the shank portion and the head portion. At least one locking thread may establish a conical periphery of the head portion. The conical periphery may be dimensioned to engage the aperture at a plurality of orientations relative to an aperture axis of the aperture. The head portion may include a proximal chamfer extending between the conical periphery and a proximal end of the fastener. The head portion may include at least one cutting flute in the conical periphery that includes a cutting surface dimensioned to engage bone. A flute profile of the at least one cutting flute may be dimensioned to interrupt neighboring thread segments of the at least one locking thread.[ooos] The present disclosure may include any one or more of the individual features disclosed above and / or below alone or in any combination thereof.

[0009] The various features and advantages of this disclosure will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows.BRIEF DESCRIPTION OF THE DRAWINGS[oooio] Figure 1 discloses a perspective view of an orthopaedic fastener including a head portion according to an implementation.[oooii] Figure 2 disclose a side view of the fastener of Figure 1.

[0012] Figure 3 discloses the head portion of the fastener of Figure 2 including one or more locking threads.[oooi3] Figure 4 discloses the head portion of the fastener of Figure 3 with the fixation locking omitted.

[0014] Figure 5 discloses an orthopaedic system including the fastener engaging an orthopaedic component at a first orientation.[ooois] Figure 6 discloses the orthopaedic system of Figure 5 including the fastener engaging the orthopaedic component at a second orientation.

[0016] Figure 7 discloses a perspective view of an orthopaedic fastener including a self-c utting feature according to another implementation.

[0017] Figure 8 disclose a side view of the fastener of Figure 7.[ooois] Figure 9 discloses a sectional view of the fastener taken along line 9-9 of Figure 8.

[0019] Figure 10 discloses another sectional view of the fastener taken along line 10-10 of Figure 8.

[0020] Figure 11 discloses a sectional view of the fastener taken along line 11- 11 of Figure 9.

[0021] Figure 12 disclose a side view of a head portion of the fastener of Figure 7.

[0022] Figure 13 discloses an orthopaedic system including the fastener engaging an orthopaedic component at various orientations.

[0023] Like reference numbers and designations in the various drawings indicate like elements.DETAILED DESCRIPTION

[0024] This disclosure relates to orthopaedic implant systems and methods for restoring functionality to various bones and joints. The systems may include one or more variable angle locking fasteners for securing various orthopaedic components at the surgical site.

[0025] The variable angle locking fasteners disclosed herein may include a scalable head geometry that may facilitate a reliable locking function with the same screw head shape when proportionally upscaled for use with larger fastener sizes. The disclosed fasteners may be utilized to engage orthopaedic components including thesame and / or different materials and may be utilized to mate with various arrangements of threads and other fixation features, including standard thread patterns which may be dimensioned to receive standard locking screws. The threads associated with the fastener head and / or aperture may include one or more interruptions, but in other implementations the interruptions may be omitted.

[0026] The disclosed variable angle locking fasteners may include a locking mechanism for improving engagement between the fastener and an aperture of an orthopaedic component, such as a bone plate. The locking mechanism may be utilized to ensure that the bone plate may sit flush to the surface of the bone during implantation while rigidly locking into the plate. The locking mechanism may include a self-cutting feature adjacent to a leading edge of the fastener head to facilitate engagement of the head in the associated aperture and subsequently the bone to ensure that the plate may sit flush to the bone.

[0027] A variable angle locking fastener for an orthopaedic procedure may include a fastener body extending along a fastener axis between a proximal end and a distal end. The fastener body may include a shank portion, a head portion, and a neck portion interconnecting the shank portion and the head portion. The shank portion may include at least one fixation thread dimensioned to engage bone. The head portion may include at least one locking thread extending about the fastener axis to establish a conical periphery of the head portion. The conical periphery may be dimensioned to engage an aperture of an orthopaedic component. A proximal chamfer may extend between the conical periphery and the proximal end.

[0028] In any implementations, the head portion may include an intermediate portion that interconnects the proximal chamfer and the conical periphery. The intermediate portion may establish a maximum diameter of the head portion. A runout of the at least one locking thread may be established at the intermediate portion.

[0029] In any implementations, crests of the at least one locking thread may be substantially aligned along a first reference plane to establish the conical periphery. The first reference plane may intersect the fastener axis to establish a first angle. A periphery of the proximal chamfer may extend along a second reference plane that intersects the fastener axis to establish a second angle. A ratio of the second angle to the first angle may be equal to or greater than 2:1.

[0030] In any implementations, the head portion may include a distal chamfer that interconnects the conical periphery and the neck portion. A periphery of the distalchamfer may extend along a third reference plane that intersects the fastener axis to establish a third angle. The third angle may be greater than the second angle.

[0031] In any implementations, the head portion may include at least one cutting flute having a wedge-shaped profile that may interrupt the at least one locking thread.

[0032] A variable angle locking fastener for an orthopaedic procedure may include a fastener body extending along a fastener axis between a proximal end and a distal end. The fastener body may include a shank portion, a head portion, and a neck portion interconnecting the shank portion and the head portion. The shank portion may include at least one fixation thread dimensioned to engage bone. The head portion may include at least one locking thread extending about the fastener axis to establish a conical periphery of the head portion. The conical periphery may be dimensioned to engage an aperture of an orthopaedic component. At least one cutting flute in the periphery may include a cutting surface dimensioned to engage bone. A flute profile of the at least one cutting flute may be dimensioned to interrupt neighboring thread segments of the at least one locking thread.

[0033] In any implementations, the flute profile may have a wedge-shaped geometry extending circumferentially from crests of the neighboring thread segments to the cutting surface relative to the fastener axis.

[0034] In any implementations, the at least one locking thread may include one or more thread segments between the proximal end of the fastener body and the at least one cutting flute.[ooo35] In any implementations, the at least one cutting flute may include a plurality of cutting flutes circumferentially distributed about the fastener axis.

[0036] In any implementations, the neck portion may be dimensioned to space apart the at least one fixation thread and the at least one locking thread. The at least one cutting flute may be distal of the at least one locking thread and extends along the neck portion.

[0037] In any implementations, the at least one cutting flute may include a relief surface extending along a relief plane. The cutting surface may extend along a cutting plane. The relief surface and the cutting surface may be joined together a valley. The relief plane and the cutting plane may intersect to establish a relief angle that may be between approximately 75 degrees and approximately 105 degrees.[ooo38] In any implementations, the cutting plane may be transverse to the fastener axis.

[0039] In any implementations, crests of the neighboring thread segments may be substantially aligned along a first reference plane to establish the conical periphery. The first reference plane may intersect the fastener axis to establish a first angle. The relief plane may intersect the fastener axis to establish a second angle. The first angle may be less than the second angle.

[0040] In any implementations, the first angle may be equal to or greater than approximately 5 degrees.

[0041] In any implementations, the at least one locking thread may include a root between the at least two neighboring thread segments. The root may intersect the cutting surface at a position radially outward of the valley relative to the fastener axis.

[0042] An orthopaedic system may include a bone plate including a plate body dimensioned to abut bone and an aperture extending through the plate body. A variable angle locking fastener may include a fastener body including a shank portion, a head portion, and a neck portion interconnecting the shank portion and the head portion. At least one locking thread may establish a conical periphery of the head portion. The conical periphery may be dimensioned to engage the aperture at a plurality of orientations relative to an aperture axis of the aperture. The head portion may include a proximal chamfer extending between the conical periphery and a proximal end of the fastener. The head portion may include at least one cutting flute in the conical periphery that includes a cutting surface dimensioned to engage bone. A flute profile of the at least one cutting flute may be dimensioned to interrupt neighboring thread segments of the at least one locking thread.

[0043] In any implementations, the head portion may include the proximal chamfer. The plurality of orientations may include a first orientation substantially equal to an angle of the conical periphery relative to a fastener axis of the fastener.

[0044] In any implementations, the head portion may include the at least one cutting flute. The flute profile may have a wedge-shaped geometry that may extend axially along the cutting surface from a position distal of the at least one locking thread and that may extend circumferentially from crests of the neighboring thread segments to the cutting surface relative to a fastener axis of the fastener.

[0045] In any implementations, the at least one cutting flute may include a relief surface extending along a relief plane. The cutting surface may extend along a cuttingplane. The relief surface and the cutting surface may be joined together a valley to establish the wedge-shaped geometry. The relief plane and the cutting plane may intersect to establish a relief angle that may be between approximately 75 degrees and approximately 105 degrees.

[0046] In any implementations, the head portion may be dimensioned to engage the aperture such that the at least one cutting flute may extend distally of the aperture relative to the aperture axis.

[0007] Figures 1-2 disclose a variable angle locking fastener 20 according to an implementation. The fastener 20 may be utilized in various orthopedic procedures to restore functionality to bones and / or joints, including various long bones such as the tibia, femur and humerus, and various joints such as the ankle. The procedures may include repair of bone fractures, fusion of bones, etc. The fastener 20 may be utilized to restore functionality to other bones and joints such as a knee, hip, elbow, wrist, shoulder, etc. The fastener 20 may be insertable at a plurality of orientations (e.g., insertion angles) to provide fixation. The fastener 20 may be a compression screw adapted to apply a compressive force on an orthopaedic component (e.g., implant) in response to securing the screw in bone. In implementations, the fastener 20 may be utilized to engage a bone plate or other orthopedic component to secure the component to one or more bones and / or bone portions. The bone plate may be utilized to secure adjacent bones and / or portions of bone to each other, including fragment(s) of a fractured bone. The fastener 20 may be utilized to compress the bone plate against the bone.

[0048] The fastener 20 may include a fastener body 22 extending along a fastener (e.g., longitudinal) axis X between a first (e.g., proximal) end 24 and a second (e.g., distal) end 26. The fastener body 22 may include a shank portion 28 and a head portion 30. The fastener body 22 may include a neck portion 32 that may interconnect the shank portion 28 and head portion 30. In other implementations, the neck portion 32 may be omitted and the shank portion 28 may extend directly from the head portion 30. The fasteners disclosed herein may incorporate various metallic materials, such as a surgical grade steel, titanium or alloy.[ooo49] The fastener 20 may include one or more threads for providing fixation. The shank portion 28 may include at least one fixation thread 34. The fixation thread 34 may be dimensioned to engage bone. In other implementations, the shank portion 28 may include two or more fixation threads 34. The head portion 30 may include atleast one locking thread 36 dimensioned to engage aperture(s) of an orthopaedic component. The head portion 30 may include any number of locking threads 36. The thread(s) 34, 36 may be dimensioned to establish various pitches and leads and may have various thread profiles.[oooso] The neck portion 32 may have various geometries. The neck portion 32 may be established by a radius swept about the fastener axis X. The radius may be substantially tangential to the distal chamfer 42. A minimum diameter of the neck portion 32 may be greater than a minor diameter of the fixation thread 34 adjacent to the neck portion 32. The minor diameter may be defined relative to a root 34R of the fixation thread 34 (Figure 2). The radius may be utilized to reduce any stress concentrations between the head portion 30 and the shank portion 26.

[0051] The head portion 30 may include various geometries for engaging aperture(s) of an orthopaedic component. The fastener 20 may be insertable at a plurality of orientations (e.g., insertion angles) relative to an axis of the aperture. The surgeon may select an insertion angle of the fastener 20 to improve bone purchase and fixation of the orthopedic component.[ooo52] The head portion 30 may include a conical periphery 38. The conical periphery 38 may establish the orientations to provide a variable angle locking function. The conical periphery 38 may be dimensioned to engage an aperture of an orthopedic component to secure the component to tissue such as bone (e.g., apertures 56 of Figures 5-6). A diameter of the conical periphery 38 may generally taper in a distal direction between the proximal and distal ends 24, 26 of the fastener 20. The locking thread(s) 36 may extend about the fastener axis X to establish the conical periphery 38.[ooo53] The conical periphery 38 may extend axially a first length LI, and the head portion 30 may extend a second (e.g., overall) length L2 relative to the fastener axis X (Figure 4). The conical periphery 38 may extend less than the overall length L2 of the head portion 30. The first length LI may be equal to or greater than approximately 40 percent of the overall length L2 of the head portion 30, or more narrowly may be equal to or greater than approximately 60 percent of the overall length L2. For the purposes of this disclosure, the terms “approximately,” “about” and “substantially” mean ±10 percent of the stated value or relationship unless otherwise indicated.

[0054] Referring to Figure 3, with continuing reference to Figures 1-2, the locking thread 36 may include two or more locking threads 36 interspersed with each other (indicated at 36-1, 36-2). The locking threads 36-1, 36-2 may extend about thefastener axis X. The locking threads 36-1, 36-2 may cooperate to establish a dual lead arrangement. The fastener 20 may include fewer or more than two locking threads 36 disposed about the head portion 30, such as only one locking thread to establish a single lead arrangement and / or three or more threads 36.

[0055] The head portion 30 may include one or more features for reducing a likelihood of interference with aperture(s) of the orthopaedic component during insertion at a selected orientation. The head portion 30 may include a first (e.g., proximal) chamfer 40 and / or a second (e.g., distal) chamfer 42. The proximal and distal chamfers 40, 42 may be established by respective conical geometries. The conical periphery 38 may be dimensioned to extend axially between the proximal chamfer 40 and distal chamfer 42 relative to the fastener axis X. The proximal chamfer 40 may extend between the conical periphery 38 and the proximal end 24 of the fastener 20. In implementations, the proximal chamfer 40 may extend to the proximal end 24. The proximal chamfer 40 may be dimensioned to space apart each locking thread 36 from the proximal end 24. The distal chamfer 42 may be dimensioned to interconnect the conical periphery 38 and the neck portion 32. The proximal chamfer 40 may reduce a likelihood of interference of head portion 30 within an aperture (e.g., locking hole) when inserted at an angle.

[0056] The proximal chamfer 40 may improve angulation of the fastener 20 by reducing a volume of material deformation that may otherwise occur due to engagement between the respective threads 36, 58 (e.g., Figure 6). The proximal chamfer 40 may reduce an overall prominence of the head portion 30 above the proximal face of the component (e.g., plate) 52 when the fastener 20 may be locked in an off-axis orientation (e.g., Figure 6). The distal chamfer 42 may improve angulation of the head portion 30 within the aperture 56 without causing or otherwise exceeding an interference. The distal chamfer 42 may reduce a volume of material of the thread(s) 36, 58 that may be deformed when the fastener may lock in an off-axis orientation (e.g., Figure 6).

[0057] The head portion 30 may include an intermediate portion 44 dimensioned to limit insertion through aperture(s) of an orthopaedic component. The intermediate portion 44 may interconnect the conical periphery 38 and proximal chamfer 40. The intermediate portion 44 may have a substantially cylindrical geometry.[oooss] A diameter of the intermediate portion 44 may be dimensioned to limit or otherwise reduce advancement of fastener 20 through an associated aperture 56 when oriented along a (e.g., nominal) axis of the aperture 56 (e.g., Figure 5). The head portion30 may include a minimum diameter DMIN and a maximum diameter DMAX, which may be spaced axially from the minimum diameter DMIN relative to the fastener axis X. The intermediate portion 44 may establish the maximum diameter DMAX of the head portion 30. A runout 46 of the respective locking thread(s) 36 may be established at the intermediate portion 44. In other implementations, the runout 46 may be established distally of the intermediate portion 44. The minimum diameter DMIN may be established distally of the distal chamfer 42, such as at a junction between the distal taper 42 and the neck portion 32. In implementations, a ratio DMIN:DMAX between the minimum diameter DMIN and the maximum diameter DMAX may be less than or equal to 3:4, or more narrowly may be less than or equal to 3:5. The ratio DMIN:DMAX may be equal to or greater than 1:4, or more narrowly may be equal to or greater than 1:2. The techniques disclosed herein may be utilized to increase a range of insertion angles of the fastener 20 and engagement between the fastener 20 and the aperture of the orthopaedic component.[ooo59] Referring to Figures 3-4, the head portion 30 may include one or more features that may improve engagement between the fastener 20 and an aperture of an orthopedic component that may receive the fastener 20. Figure 4 discloses an implementation of the fastener 20 with the locking thread(s) 36 omitted (e.g., prior to formation of the threads 36).

[0060] The locking thread(s) 36 may establish the conical periphery 38 of the head portion 30. Crests 36C of the respective locking thread 36 may be substantially aligned along a first reference plane REFI to establish the conical periphery 38. The first reference plane REFI may intersect the fastener axis X to establish a first (e.g., taper) angle a. In implementations, the taper angle a may be equal to or greater than approximately 5 degrees, or more narrowly may be less than or equal to 20 degrees, such as between approximately 10 degrees and approximately 15 degrees. A periphery of the proximal chamfer 40 may extend along a second reference plane REF2. The second reference plane REF2 may intersect the fastener axis X to establish a second (e.g., chamfer) angle p. The first and second reference planes REFI, REF2 may intersect at a transverse (e.g., obtuse) angle. A periphery of the distal chamfer 42 may extend along a third reference plane REF3. The third reference plane REF3 may intersect the fastener axis X to establish a third (e.g., chamfer) angle cp. The angles a, and / or q> may be the same or may differ. In implementations, a ratio of the chamfer angle P to the taper angle a may be equal to or greater than 2: 1, or more narrowly maybe equal to or greater than 3: 1. The chamfer angle q> may be greater than the taper angle a and / or chamfer angle p. The distal chamfer 42 may be dimensioned such that a diameter of the head portion 30 may decrease from the distal end of the conical periphery 38 toward the distal end 26 of the fastener 20.[ooo6i] The head portion 30 may include at least one or more cutting flutes that may interrupt the locking thread(s) 36 (e.g., cutting flutes 160 of Figures 7-8). The cutting flutes may have a wedge-shaped or other profile. In other implementations, the cutting flutes may be omitted.[ooo62] Referring to Figures 5-6, with continued references to Figures 2-4, an orthopedic system 50 for an orthopaedic procedure is disclosed according to implementation. The system 50 may incorporate any of the fasteners disclosed herein, such as the fastener 20. The system 50 may include an orthopedic component 52. The component 52 may be utilized to treat any of the bones and joints disclosed herein. In implementations, the component 52 may be a bone plate dimensioned to abut bone B. The system 50 may be provided as an orthopaedic kit. The kit may include fasteners 20 and / or components 52 of various geometries and sizes for treating patients.[ooo63] The bone plate 52 may include a main (e.g., plate) body 54 dimensioned to abut bone B. The bone plate 52 may include at least one aperture 56 dimensioned to extend through the plate body 54. The bone plate 52 may include any number of apertures 56 in accordance with teachings disclosed herein. The aperture 56 may be dimensioned to extend along an aperture (e.g., longitudinal) axis A between a proximal face and distal face of the plate body 54. The bone plate 52 may include one or more (e.g., plate) threads 58 disposed along the respective aperture 56. The plate threads 58 may be dimensioned to engage the locking thread(s) 36 to secure the bone plate 52 to bone B. Engagement between the locking thread(s) 36 and the plate thread(s) 58 may establishing a locking relationship, which may oppose disengagement between the fastener 20 and bone plate 52.[ooo64] The conical periphery 38 of the fastener 20 may be dimensioned to engage the aperture 56 at a plurality of orientations relative to the aperture axis A of the aperture 56. In the implementation of Figure 5, the fastener 20 may be arranged at a first orientation relative to the aperture 56 such that the fastener axis X may be substantially aligned with the aperture axis A. A minimum diameter DA of the aperture 58 may be greater than the minimum diameter DMIN of the head portion 30 to facilitate insertion of the fastener 20 at a range of orientations relative to the aperture axis A. Inthe implementation of Figure 6, the fastener 20 may be arranged at a second orientation relative to the aperture 56 such that the fastener axis X may be transverse to the aperture axis A. The second orientation of the fastener axis X relative to the aperture axis A may be less than or substantially equal to the taper angle a of the conical periphery 38 (Figure 4). The proximal taper 40 may be spaced apart from the plate thread(s) 58 when positioned in the second orientation, which may facilitate insertion of the fastener 20 at a range of orientations (e.g., insertion angles). Engagement between the locking and plate threads 36, 58 may cause the locking thread(s) 36 and / or the plate thread(s) 58 to deflect in response to orienting the fastener 20 at a transverse angle relative to the aperture axis A.[ooo65] Figures 7-8 disclose a variable angle locking fastener 120 for an orthopedic procedure according to another implementation. In this disclosure, like reference numerals designate like elements where appropriate and reference numerals with the addition of one -hundred or multiples thereof designate modified elements that are understood to incorporate the same features and benefits of the corresponding original elements. The fastener 120 may incorporate any of the features of the fastener 20, and vice versa.

[0066] The fastener 120 may include a fastener body 122 that may extend along a fastener (e.g., longitudinal) axis X between a first (e.g., proximal) end 124 and a second (e.g., distal) end 126. The fastener body 122 may include a shank portion 128, head portion 130 and / or neck portion 132 that may interconnect the shank portion 128 and head portion 130. In implementations, the neck portion 132 may be omitted. The shank portion 128 may include one or more fixation threads 134 dimensioned to engage bone. The head portion 130 may include one or more locking threads 136 that may be dimensioned to extend about the fastener axis X to establish a conical periphery 138 of the head portion 130. The conical periphery 138 may be dimensioned according to any of the techniques disclosed herein. The conical periphery 138 may be dimensioned to engage an aperture of an orthopedic component (e.g., apertures 156 of Figure 13). The head portion 130 may include a transition section 131 between the conical periphery 138 and the proximal end 124 of the fastener 120. In other implementations, the head portion 130 may have a non-conical periphery, such as a generally spherical or cylindrical profile. The transition section 131 may have a rounded geometry or may establish a chamfer. The neck portion 132 may be dimensioned to space apart the fixation thread(s) 134 and locking thread(s) 136.

[0067] The fastener 120 may include a self-cutting feature to facilitate insertion in bone and / or other tissue. The fastener 120 may include one or more cutting flutes 160 that may be dimensioned to cut or otherwise engage bone to establish the selfcutting feature. The cutting flutes 160 may facilitate insertion of the fastener 120 in the adjacent bone. The fastener 120 may include at least one or more cutting flutes 160 in the conical periphery 138 of the head portion 130. Each cutting flute 160 may include a respective cutting surface (e.g., face) 162. The cutting surface 162 may be dimensioned to cut or otherwise engage bone. Each cutting flute 160 may be associated with a respective flute profile 164. In implementations, the flute profile 164 of the cutting flute 160 may be dimensioned to interrupt neighboring thread segments 166 of the respective locking thread(s) 136 between the proximal end 124 and distal end 126 of the fastener 120. In the implementation of Figures 9-10, the fastener 120 may include a plurality of cutting flutes 160 circumferentially distributed about the fastener axis X. The fastener 120 may include three cutting flutes 160 at approximately 120 degree intervals. The fastener 120 may include fewer or more than three cutting flutes 160 in accordance with the teachings disclosed herein. The cutting flute 160 may be contiguous or may include two or more discrete segments 161 (e.g., segments 161-1, 162-2) that may establish the flute profile 164. The segments 161-1, 161-2 may be spaced apart by root(s) 136R of the locking thread(s) 136.

[0068] The cutting flute 160 may be dimensioned relative to an axial span of the locking thread(s) 136 relative to the fastener axis X. The cutting flute 160 may be dimensioned to extend axially at least, or only, partially across the locking thread(s) 136 relative to the fastener axis X. The locking thread(s) 136 may include one or more thread segments 166 between the proximal end 124 of the fastener body 122 and the cutting flute 160. In other implementations, the cutting flute 160 may be dimensioned to extend completely across the locking thread(s) 136 relative to the fastener axis X.[ooo69] The cutting surface 162 and / or other portions of the cutting flute 160 may be dimensioned to extend distally of the locking thread 136. The flute profile 164 may have various geometries, such as an elongated groove. The flute profile 164 may have a wedge-shaped geometry that may extend axially along the cutting surface 162 from a position distal of the locking thread 136. In implementations, the cutting flute 160 may include a portion that may extend along the neck portion 132. The cutting flute 160 may engage bone prior to the adjacent locking thread 136 in response to insertion of the fastener 120 in the bone.

[0070] Referring to Figures 9-10, continuing reference to Figures 7-8, a cross section of the flute profile 164 may have a substantially wedge-shaped geometry. The wedge-shaped geometry may extend circumferentially from the crest(s) 136C of the neighboring thread segment(s) 166 to the cutting surface 162 relative to the fastener axis X. A junction between the crest(s) 136C and the flute profile 164 may serve as an entrance to the cutting flute 160 relative to a rotational (e.g., insertion) direction of the fastener 120. The locking thread(s) 136 may include a root 136R between the respective neighboring thread segments 166.

[0071] The cutting flute 160 may include a relief surface (e.g., face) 168. The relief surface 168 may be dimensioned to face radially outward relative to the fastener axis X. The relief surface 168 and cutting surface 162 may be joined together at a valley 170 to establish the wedge-shaped geometry of the cutting flute 160. The relief surface 168 may be dimensioned to slope radially inwardly from the periphery 138 of the head portion 130. In implementations, the cutting surface 162 and / or relief surface 168 may be dimensioned to extend across the segments 161 to establish the flute profile 164. The locking thread(s) 136 may be dimensioned such that one or more roots 136R may intersect the cutting surface 162 at a position radially outward of the valley 170 relative to the fastener axis X (e.g., segment 161-1 of Figures 7-8). In other implementations, one or more roots 136R may be substantially aligned with, or may be radially inward of, the valley 170 associated with one or more of the segments 161 (e.g., segment 161- 2 of Figures 7-8).[ooo72] The cutting surface 162 and relief surface 168 may have various geometries. The cutting surface 162 and / or relief surface 168 may have a substantially planar geometry or may have a convex, concave or other non-planar geometry. The cutting surface 162 and relief surface 168 may be arranged at various orientations relative to each other to facilitate a cutting function. The relief surface 168 may extend along a fourth reference (e.g., relief) plane REF4. The cutting surface 162 may extend along a fifth reference (e.g., cutting) plane REF5. The relief surface 168 and cutting surface 162 may be dimensioned to extend along the respective planes REF4, REF5 to establish the segments 161 of the cutting flute 160. The relief plane REF4 and cutting plane REF5 may intersect to establish a relief (e.g., ramp) angle A. The relief angle A may be between approximately 75 degrees and approximately 105 degrees. In implementations, the relief angle A may be approximately 90 degrees such that thecutting surface 162 and relief surface 168 may be substantially perpendicular to each other.

[0073] Referring to Figure 11, with continuing references to Figures 7-10, the crests 136C of the neighboring thread segments 166 may be substantially aligned along a first reference plane REFI to establish the conical periphery 138. The first reference plane REFI may intersect the fastener axis X to establish a first (e.g., taper) angle a. The relief plane REF4 may intersect the fastener axis X to establish a fourth angleIn implementations, the taper angle a may be less than the fourth angle \p. The fourth angle \| / may be greater than the taper angle a such that the cutting flute 160 may terminate prior to the locking thread(s) 136 relative to the proximal direction.

[0074] Referring to Figure 12, the cutting surface 162 may be established at various orientations relative to the fastener axis X. The cutting surface 162 may be established such that the cutting plane REF5 may be transverse to the fastener axis X. The cutting plane REF5 may establish a fifth (e.g., cutting) angle (|> relative to the fastener axis X. The cutting angle may be greater than zero degrees, such as between approximately 1 degree and approximately 15 degrees. In other implementations, the cutting angle (|> may be 0 degrees such that the cutting plane REF5 may be substantially parallel to the fastener axis X. The disclosed geometries may facilitate cutting through the bone and / or other tissue during advancement of the fastener 120.

[0075] Referring to Figure 13, with continuing reference to Figures 7-8, an orthopedic system 150 for an orthopaedic procedure is disclosed according to implementation. The system 150 may incorporate any of the fasteners disclosed herein, such as the fastener 120. The system 150 may include an orthopedic component 152. The component 152 may be utilized to treat any of the bones and joints disclosed herein. In implementations, the component 152 may be a bone plate dimensioned to abut bone B. The system 150 may be provided as an orthopaedic kit. The kit may include fasteners 120 and / or components 152 of various geometries and sizes for treating patients.

[0076] The bone plate 152 may include one or more apertures 156. Each aperture 156 may include one or more plate threads 158 that may engage the locking thread(s) 136 of the fastener 120 to secure the bone plate 152 to bone B. The cutting surface 162 may be dimensioned to engage bone B in response to rotation of the head portion 130 in a first rotational direction R1 about the fastener axis X. The rotational direction R1 may be clockwise or counterclockwise. The fastener thread(s) 136 may be established such that the portion of the relief surface 168 (Figures 7-8) on an oppositeside of the cutting flute 160 as the cutting surface 162 may lead the cutting surface 162 in response to rotating the fastener 120 in the rotational direction R1 to advance the fastener 120 in the bone B. The cutting flute 160 may be dimensioned to cut at least partially through cortical bone during advancement of the fastener 120.

[0077] In the implementation of Figure 12, the fasteners 120 may include a first fastener 120-1 and a second fastener 120-2. Each fastener 120 may be insertable at a plurality of orientations (e.g., insertion angles) relative to an aperture (e.g., longitudinal) axis A of the aperture 156. The surgeon may select an insertion angle of the fastener 120 to improve bone purchase and fixation of the bone plate 152. The head portion 130 may be dimensioned to engage the aperture 156 such that the cutting flute 160 may extend distally of the aperture 156 relative to the aperture axis A when the head portion 130 is seated in the aperture 156 at one or more orientations.

[0078] In implementations, the fastener 120-1 may be arranged at a first orientation relative to the aperture 156 such that the fastener axis X may be substantially aligned with the aperture axis A of the aperture 156. The fastener 120-2 may be arranged at a second orientation relative to the aperture 156 such that the fastener axis X may be transverse to the aperture axis A of the aperture 156. The fastener 120 may inserted through the aperture 156 such that one or more of the cutting flutes 160 may cut or otherwise engage the bone B in response to rotating the fastener 120 about the fastener axis X. Inserting the fastener 120-2 at an oblique angle relative to the aperture axis A may increase a portion of the cutting flute 160 that may engage the bone B. The cutting flute 160 may engage the bone B prior to a lead of the locking thread 136, since the thread lead may otherwise function as a stop when engaging the bone B to inhibit further insertion of the fastener 120 were the cutting flute 160 to be omitted.

[0079] The disclosed fasteners may be useful in treating various bones and joints and may provide improved engagement between the fastener and orthopaedic component associated with a range of orientations. The surgeon may select a relatively greater range of orientations to insert the fastener, which may improve bone purchase and fixation. The fasteners may include one or more cutting features to facilitate insertion in bone and engagement of fixation threads along the fastener head to improve seating the fastener in the bone, which may improve fixation of the bone plate or other orthopaedic component when implanted in the patient.[oooso] Although the different non-limiting embodiments are illustrated as having specific components or steps, the embodiments of this disclosure are not limitedto those particular combinations. It is possible to use some of the components or features from any of the non-limiting embodiments in combination with features or components from any of the other non-limiting embodiments.[ooosi] It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings. It should further be understood that although a particular component arrangement is disclosed and illustrated in these exemplary embodiments, other arrangements could also benefit from the teachings of this disclosure.[ooo82] The foregoing description shall be interpreted as illustrative and not in any limiting sense. A worker of ordinary skill in the art would understand that certain modifications could come within the scope of this disclosure.

Claims

CLAIMSWhat is claimed is:

1. A variable angle locking fastener for an orthopaedic procedure comprising: a fastener body extending along a fastener axis between a proximal end and a distal end, wherein the fastener body includes a shank portion, a head portion, and a neck portion interconnecting the shank portion and the head portion; wherein the shank portion includes at least one fixation thread dimensioned to engage bone; and wherein the head portion comprises: at least one locking thread extending about the fastener axis to establish a conical periphery of the head portion, and the conical periphery dimensioned to engage an aperture of an orthopaedic component; and at least one cutting flute in the periphery that includes a cutting surface dimensioned to engage bone, and a flute profile of the at least one cutting flute dimensioned to interrupt neighboring thread segments of the at least one locking thread.

2. The fastener as recited in claim 1, wherein: the flute profile has a wedge-shaped geometry extending circumferentially from crests of the neighboring thread segments to the cutting surface relative to the fastener axis.

3. The fastener as recited in claim 1 or 2, wherein: the at least one locking thread includes one or more thread segments between the proximal end of the fastener body and the at least one cutting flute.

4. The fastener as recited in any preceding claim, wherein: the at least one cutting flute includes a plurality of cutting flutes circumferentially distributed about the fastener axis.

5. The fastener as recited in any preceding claim, wherein:the neck portion is dimensioned to space apart the at least one fixation thread and the at least one locking thread; and the at least one cutting flute is distal of the at least one locking thread and extends along the neck portion.

6. The fastener as recited in any preceding claim, wherein the at least one cutting flute includes a relief surface extending along a relief plane, the cutting surface extends along a cutting plane, the relief surface and the cutting surface are joined together a valley, and the relief plane and the cutting plane intersect to establish a relief angle that is between approximately 75 degrees and approximately 105 degrees.

7. The fastener as recited in claim 6, wherein the cutting plane is transverse to the fastener axis.

8. The fastener as recited in claim 6 or 7, wherein crests of the neighboring thread segments are substantially aligned along a first reference plane to establish the conical periphery, the first reference plane intersects the fastener axis to establish a first angle, the relief plane intersects the fastener axis to establish a second angle, and the first angle that is less than the second angle.

9. The fastener as recited in claim 8, wherein the first angle is equal to or greater than approximately 5 degrees.

10. The fastener as recited in any of claims 6 to 9, wherein: the at least one locking thread includes a root between the at least two neighboring thread segments; and the root intersects the cutting surface at a position radially outward of the valley relative to the fastener axis.

11. The fastener as recited in any preceding claim, further comprising: a proximal chamfer extending between the conical periphery and the proximal end of the fastener body.

12. The fastener as recited in claim 11, wherein: the head portion includes an intermediate portion that interconnects the proximal chamfer and the conical periphery, the intermediate portion establishes a maximum diameter of the head portion, and a runout of the at least one locking thread is established at the intermediate portion.

13. The fastener as recited in claim 11 or 12, wherein: crests of the at least one locking thread are substantially aligned along a first reference plane to establish the conical periphery, and the first reference plane intersects the fastener axis to establish a first angle; a periphery of the proximal chamfer extends along a second reference plane that intersects the fastener axis to establish a second angle; and a ratio of the second angle to the first angle is equal to or greater than 2:1.

14. The fastener as recited in claim 13, wherein: the head portion includes a distal chamfer that interconnects the conical periphery and the neck portion; a periphery of the distal chamfer extends along a third reference plane that intersects the fastener axis to establish a third angle; and the third angle is greater than the second angle.

15. An orthopaedic system comprising: a bone plate including a plate body dimensioned to abut bone and an aperture extending through the plate body; and a variable angle locking fastener comprising: a fastener body including a shank portion, a head portion, and a neck portion interconnecting the shank portion and the head portion; at least one locking thread that establishes a conical periphery of the head portion, and the conical periphery dimensioned to engage the aperture at a plurality of orientations relative to an aperture axis of the aperture; and wherein the head portion includes at least one of the following: a proximal chamfer extending between the conical periphery and a proximal end of the fastener; and / or at least one cutting flute in the conical periphery that includes a cutting surface dimensioned to engage bone, and a flute profile of the at least one cutting flute dimensioned to interrupt neighboring thread segments of the at least one locking thread.

16. The system as recited in claim 15, wherein the head portion includes the proximal chamfer, and the plurality of orientations include a first orientation substantially equal to an angle of the conical periphery relative to a fastener axis of the fastener.

17. The system as recited in claim 15 or 16, wherein the head portion includes the at least one cutting flute.

18. The system as recited in claim 17, wherein the flute profile has a wedge-shaped geometry extending axially along the cutting surface from a position distal of the at least one locking thread and extending circumferentially from crests of the neighboring thread segments to the cutting surface relative to a fastener axis of the fastener.

19. The system as recited in claim 18, wherein the at least one cutting flute includes a relief surface extending along a relief plane, the cutting surface extends along a cuttingplane, the relief surface and the cutting surface are joined together a valley to establish the wedge-shaped geometry, and the relief plane and the cutting plane intersect to establish a relief angle that is between approximately 75 degrees and approximately 105 degrees.

20. The system as recited in any of claims 15 to 19, wherein: the head portion is dimensioned to engage the aperture such that the at least one cutting flute extends distally of the aperture relative to the aperture axis.

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