Lateralized dual mobile assembly

Abstract

A modular acetabular cup assembly includes an acetabular cup and a liner seated in the cup. The cup includes an end face, an apex opposite the end face, and a central axis extending between the apex and a center point of the end face. The liner includes an articulating surface having a center of rotation that defines a pivot point of the acetabular cup assembly. In certain embodiments, the pivot point is laterally offset from the center point such that the end face is between the pivot point and the apex.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 409,064, filed October 17, 2016, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] This disclosure generally relates to an acetabular cup liner having a lateral pivot point, and more specifically, but not exclusively, to a dual-movement assembly including such an acetabular cup liner. Background Technology

[0004] In certain total hip arthroplasty (THA) procedures, joint stability can be improved by increasing the tension supplied to the joint-associated soft tissues. Modern modular dual-mobility hip systems have shown promise in reducing dislocation rates by introducing a femoral head that is larger than that of conventional THA systems, but the degree to which tension in the joint is addressed in modular options is limited compared to conventional THA. In some existing modular dual-mobility systems, an inner head component is mounted to a femoral component, and an outer head component is pivotally mounted to the inner head component to provide a dual-mobility femoral head assembly. In these dual-mobility configurations, the head length selection is geometrically limited, thus restricting the soft tissue tension options available compared to conventional THA configurations.

[0005] In some conventional dual-movement assemblies of the aforementioned types, a tapered structure with a skirted femoral head is utilized for stretching, thereby increasing soft tissue tension. However, the selection of the head length for modular femoral heads has been limited due to the increased risk of intraprosthetic dissociation between the skirted femoral head and the movable support insert, as well as suboptimal wear characteristics.

[0006] While dual-movement supports have shown promise in reducing dislocation rates, further reductions in the risk of such dislocations are still desired. For these and other reasons, further improvements in this technological field remain necessary. Summary of the Invention

[0007] A modular acetabular cup assembly includes an acetabular cup and a liner located within the cup. The cup includes an end face, a vertex opposite the end face, and a central axis extending between the vertex and the center point of the end face. The liner includes an articular surface having a center of rotation that defines a pivot point for the acetabular cup assembly. In some embodiments, the pivot point is laterally offset from the center point such that the end face is located between the pivot point and the vertex. Attached Figure Description

[0008] Figure 1 This is an exploded cross-sectional view of a total hip replacement system including a dual-movement component according to one embodiment.

[0009] Figure 2 is Figure 1 a cross-sectional view of the dual mobility assembly illustrated in

[0010] Figure 3 is a cross-sectional view of a liner usable in conjunction with the dual mobility assembly illustrated in Figure 1

[0011] Figure 4 is a cross-sectional view of one embodiment of a liner series including first, second, and third liner varieties.

[0012] Figure 5 is a cross-sectional view of a first configuration of the dual mobility assembly including Figure 4 the first liner variety illustrated in

[0013] Figure 6 is a cross-sectional view of a second configuration of the dual mobility assembly including Figure 4 the second liner variety illustrated in

[0014] Figure 7 is a cross-sectional view of a third configuration of the dual mobility assembly including Figure 4 the third liner variety illustrated in

[0015] Figure 8 is a cross-sectional view of a dual mobility assembly kit according to one embodiment.

[0016] Figure 9 is a cross-sectional view of a liner according to one embodiment.

[0017] Figure 10 is a perspective view of the liner illustrated in Figure 9

[0018] Figure 11 is a cross-sectional view of an acetabular cup assembly according to one embodiment.

[0019] Figure 12 is a cross-sectional view of an acetabular cup that can be used in conjunction with certain embodiments of the present invention.

[0020] Figure 13 and Figure 14 is Figure 1 another view of the total hip replacement system illustrated in Figure 5 with the dual mobility assembly in a first configuration.

[0021] Figure 15 and Figure 16 is Figure 1 another view of the total hip replacement system illustrated in Figure 6 ​​The second configuration is shown in the figure.

[0022] Figure 17 and Figure 18 yes Figure 1 Another view of the total hip replacement system illustrated in the figure, in which the dual-movement component is located Figure 7 The third configuration shown in the diagram.

[0023] Figure 19 yes Figure 9 and 10 Another illustration of the lining shown in the figure. Detailed Implementation

[0024] For the purpose of promoting understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings, and these embodiments will be described using specific language. However, it should be understood that this is not intended to limit the scope of the invention in any way. Any changes and further modifications to the described embodiments, as well as any other applications of the principles of the invention described herein, are contemplated by those skilled in the art to which this invention pertains.

[0025] As used herein, the term "mediolateral" is used to describe movement or spacing along the first axis, and the term "lateral" is used to indicate movement or spacing along a second axis extending laterally perpendicular to the first axis. For example, in Figure 2 In the coordinate system illustrated, the first or middle axis is depicted as the vertical Y-axis, and the second or transverse axis is depicted as the horizontal X-axis. Additionally, the middle Y-axis defines the inner direction (Y). + ) and the relative lateral direction (Y) – ),exist Figure 2 The numbers in the image represent the upward direction (Y). + ) and downward direction (Y) – The terms are used to describe the orientation of the system relative to its environment. Furthermore, movement or spacing along one of the axes does not preclude movement or spacing along the other axis. For example, elements described as laterally offset from each other (i.e., offset along the lateral X-axis) may also be offset from each other in a mid-lateral direction, or may be aligned with each other in a mid-lateral manner. These terms should therefore not be construed as limiting the scope of the subject matter described herein.

[0026] Also, it is to be understood that items included in a list in the form of “at least one of A, B, and C” can mean (A); (B); (C); (A and B); (B and C); (A and C); or (A, B and C). Similarly, items listed in the form of “at least one of A, B, or C” can mean (A); (B); (C); (A and B); (B and C); (A and C); or (A, B and C). Further, the use of the terms “about” and “substantially” with respect to a given reference number should be understood to include variations of the given reference number as would be understood by one of ordinary skill in the art to be within the scope of the given reference number, unless explicitly indicated otherwise. In addition, the use of the term “or” in the claims is used to mean “and / or” unless explicitly indicated otherwise.

[0027] Referring to Figure 1 and Figure 2 A total hip replacement system 100 according to certain embodiments is shown. According to certain embodiments, system 100 is configured for use in a total hip replacement procedure, and generally includes a femoral component 110 configured for implantation in a femur, an acetabular cup 120 configured for implantation in a hip joint, and a dual mobility assembly 200. Dual mobility assembly 200 is mounted between femoral component 110 and acetabular cup 120, and defines a dual pivot axis 270 about which femoral component 110 pivots relative to acetabular cup 120. As described in further detail below, dual pivot axis 270 includes a first pivot point 275 and a second pivot point 276, and defines an offset distance 279 between first pivot point 275 and second pivot 276. In the illustrated embodiment, pivot points 275, 276 are offset from one another such that offset distance 279 has a non-trivial, non-zero value. In other embodiments, pivot points 275, 276 can coincide with one another such that offset distance 279 is zero, or can substantially coincide with one another such that offset distance 279 has a trivial, non-zero value.

[0028] Referring additionally to Figure 2The dual-movement assembly 200 generally includes a head 210 mounted to the femoral component 110, a liner 230 mounted in the acetabular cup 120, and an insert 220 mounted between the head 210 and the liner 230. The dual-movement assembly 200 provides the system 100 with a first articular interface 250 and a second articular interface 260, each of which allows the femoral component 110 to pivot relative to the cup 120 about a dual pivot 270. More specifically, the first articular interface 250 is defined between the head 210 and the insert 220 and facilitates relative pivoting movement of the head 210 and the insert 220 about a first pivot point 275. Similarly, the second articular interface 260 is defined between the insert 220 and the liner 230 and facilitates relative pivoting movement of the insert 220 and the liner 230 about a second pivot point 276.

[0029] The components of the illustrated dual-movement assembly 200 are modular, facilitating assembly of the dual-movement assembly 200 in each of multiple configurations by selecting one or more components from a series of similar components. Each series of components provides at least one variable characteristic for a corresponding component, enabling the dual-movement assembly 200 to adjust at least one characteristic of the system 100. As described in further detail below, the illustrated dual-movement assembly 200 provides the system 100 with an adjustable position relative to the dual pivots 270. More specifically, the assembly 200 allows the second pivot point 276 to be movable in at least one of the mid-lateral and lateral directions, thereby enabling the surgeon to adjust the tension in the soft tissues associated with the hip joint where the system 100 is implanted.

[0030] The femoral component 110 includes a body 112, a rod 114 extending distally from the body 112 along a rod axis 115, and a neck 116 extending from the body 112 to a tapered end 118 along a neck axis 117. The rod 114 is configured to insert into the medullary canal of the prepared femur and may be porous to facilitate inward bone growth. The neck axis 117 is angularly offset from the rod axis 115 by an angle corresponding to the angle defined between the neck and axis in a healthy femur. The tapered end 118 includes tapered sidewalls 119 defining a cone angle relative to the neck axis 117 and providing a substantially truncated conical geometry for the tapered end 118.

[0031] The exemplary cup 120 is generally hemispherical and includes a cup end face 121 extending along a cup end face plane 121', a cup inner surface 122 defining a cup cavity 123, and a cup outer surface 124. The end face 121 has a center point 126 and defines an end face opening 131 having a center point 136 that, in the illustrated form, coincides with the center point 126 of the end face 121. The center points 126, 136 can be referred to herein alternatively as a cup face center point 126 and a cup opening center point 136. As described herein, the cup face center point 126 can be used as a reference point for describing the location of one or more features relative to the cup 120. Thus, the cup face center point 126 can be referred to herein alternatively as a reference point 126.

[0032] The end face opening 131 is connected to the cavity 123, which is sized and configured to receive the liner 230. The outer surface 124 is configured to interface with a prepared acetabulum and can be porous to promote bony ingrowth. The cup 120 has an outer apex 125, an inner apex 135, and a central axis 127. In the illustrated form, the central axis 127 extends from the outer apex 125 to the center point 126 of the end face 121 and includes the inner apex 135. The illustrated cup 120 also includes a top opening 128 formed at the outer apex 125 and extending along the central axis 127. Additionally, the cavity 123 has a depth dimension 133 extending along the central axis 127 from the inner apex 135 to the center point 136 of the end face opening 131. Further details regarding the cup 120 are provided below with reference to FIGS. 2-4. Figure 12 Further details regarding the cup 120 are provided.

[0033] The head 210 includes a head end face 211 extending along a head end face plane 211', an inner articulation surface 212, and an outer articulation surface 214. The inner surface 212 defines a head cavity 213 sized and configured to receive the tapered end 118 of the neck 116. The head cavity 213 is defined in part by a tapered wall 219 that engages the tapered sidewall 119 to secure the head 210 to the femoral component 110. In certain embodiments, the head 210 can be formed of a ceramic material. In other embodiments, the head 210 can be formed of a metallic material, such as zirconia, diffusion hardened zirconia, or cobalt-chrome alloy.

[0034] The insert 220 includes an insert end face 221 extending along an insert end face plane 221', an inner articular surface 222, and an outer articular surface 224. The inner surface 222 has an inner apex 225, and the outer surface 224 has an outer apex 225'. The inner surface 222 forms an insert cavity 223 sized and configured to receive the head 210. The insert 220 can also include a tapered entrance 226 connected to the end face 221 to facilitate insertion of the head 210 into the cavity 223. The tapered entrance 226 can also provide a support surface that engages the neck 116 as the femoral component 110 is pivoted, thereby causing the insert 220 to pivot within the liner 230 when the system 100 is assembled. The insert 220 can be formed, for example, of a polymeric material, such as standard polyethylene, cross-linked polyethylene, or ultra-high molecular weight polyethylene (UHMWPE).

[0035] Further reference is made to Figure 3 The liner 230 is generally hemispherical and includes a liner end face 231 extending along a liner end face plane 231', an inner articular surface 232 defining a liner cavity 233, and an outer surface 234. The end face 231 has a central point 236, and defines an end face opening 241 having a central point 246. The central points 236, 246 can be alternatively referred to herein as a liner central point 236 and a liner opening central point 246. The end face opening 241 is connected to the cavity 233, which is sized and configured to receive the insert 220. The liner 230 has an outer apex 235 and an inner apex 245. The inner apex 245 can alternatively be considered as an apex of the inner surface 232 and / or an apex of the liner cavity 233. The liner 230 can be formed, for example, of a metallic material, such as a diffusion-hardened zirconia or a cobalt-chrome alloy.

[0036] The liner 230 has a geometric axis 237 extending from the outer apex 235 to the central point 236 of the liner end face 231. The outer surface 234 includes a protrusion 238 extending along the geometric axis 237 from the outer apex 235. The outer surface 234 can include a tapered wall 234T that engages a corresponding tapered wall 122T of the cup inner surface 122. When the liner 230 is received in the cup 120, the geometric axis 237 is aligned with the cup central axis 127, and the protrusion 238 extends into the top opening 128. The outer surface 234 is configured to engage the cup inner surface 122 to releasably or fixedly secure the liner 230 to the cup 120. For example, the surfaces 122, 234 can include mating features that selectively retain the liner 230 within the cavity 123 of the cup 120. Additionally, the mating features can enable the liner 230 to be installed in the cup 120 in each of a plurality of rotational orientations relative to the cup axis 127. Certain non-limiting examples of such mating features are described in U.S. Patent No. 9,463,094 to Allen et al., the contents of which are incorporated herein by reference in their entirety.

[0037] When seated in the liner 230, the insert 220 can pivot about the second pivot point 276 with three degrees of rotational freedom. In other words, the insert 220 can rotate about each of three mutually orthogonal axes that intersect at the center point 246 of the end face opening 241. For simplicity and convenience of description, it can be considered that two of the rotational axes are defined along the plane 241' of the end face opening 241, and the third rotational axis 247 can be considered to extend from the center point 246 to the inner vertex 245. In the illustrated embodiment, the center of the liner cavity 233 is at the geometric axis 237 of the liner 230. Thus, the center points 236, 246 coincide with each other, the inner vertex 245 lies on the geometric axis 237, and the rotational axis 247 coincides with the geometric axis 237. However, as described in further detail below, it is also contemplated that the rotational axis 247 can be offset from the geometric axis 237.

[0038] The liner 230 has an effective height 242, a cavity height 243, and a vertex thickness 244, each of which is measured in a medial direction perpendicular to the end face 231 (i.e., in a vertical direction of the Figure 3 More specifically, the cavity height 243 is the distance from the inner vertex 245 to the end face 231 medially, the thickness 244 is the distance from the outer vertex 235 to the inner vertex 245 medially, and the effective height 242 includes the cavity height 243 and the thickness 244. When the liner 230 is fully seated in the cup 120, the effective height 242 corresponds to the height of the liner 230 relative to the cup inner vertex 135. As noted above, when the liner 230 is seated in the cup 120, the protrusion 238 is received in the top opening 128. Thus, the height of the protrusion 238 need not be included when considering the effective height 242 of the liner 230.

[0039] With particular reference to Figure 2The first articulation interface 250 includes a first outer surface 252 formed by the insert 220 and a first inner surface 254 formed by the head 210. More specifically, the outer surface 252 is defined by the inner articulation surface 222 of the insert 220, and the inner surface 254 is defined by the outer articulation surface 214 of the head 210. Each of the outer surface 252 and the inner surface 254 corresponds to a respective cap of a first sphere 256 having a first diameter 258 and centered at a first pivot point 275. As used herein, a cap or spherical cap of a sphere is the region of the sphere that lies on one side of a given plane that intersects the sphere. For example, the outer surface 252 corresponds to the portion of the sphere 256 above the plane 253, and the inner surface 254 corresponds to the portion of the sphere 256 above the plane 255. Thus, each of the surfaces 252, 254 can be considered to be spherical about the first pivot point 275. As used herein, the term "spherical" is used to describe a geometry defined by at least a portion of a sphere, and does not necessarily require that the feature being described define an entire sphere. Those skilled in the art will readily appreciate that where a plane intersects a sphere to define a spherical cap, a line normal to the plane and extending through the center of the sphere intersects the apex of the cap.

[0040] It will be appreciated that the nominal diameter D222 of the insert inner surface 222 can be slightly larger than the nominal diameter D214 of the head outer surface 214. This feature may, for example, ensure that the head 210 and the insert 220 remain pivotable relative to one another while allowing for variation in the diameters D214, D222 within manufacturing tolerances. In this case, each of the surfaces 252, 254 can still be considered to correspond to a cap of the sphere 256, and each of the diameters D214, D222 can still be considered to correspond to the diameter 258 of the sphere 256.

[0041] The second articulation interface 260 includes a second outer surface 262 formed by the liner 230 and a second inner surface 264 formed by the insert 220. More specifically, the outer surface 262 is defined by the inner articulation surface 232 of the liner 230, and the inner surface 264 is defined by the outer articulation surface 224 of the insert 220. Each of the outer surface 262 and the inner surface 264 corresponds to a respective cap of a second sphere 266 having a second diameter 268 and centered at a second pivot point 276. For example, the outer surface 262 corresponds to the portion of the sphere 266 above the plane 263, and the inner surface 264 corresponds to the portion of the sphere 266 above the plane 265. In the illustrated form, the plane 263 is defined at the end face 231 of the liner 230 and intersects the second pivot point 276. Thus, the spherical cap corresponding to the outer surface 262 is a hemisphere. It is also contemplated that, for example, in embodiments where the plane 263 does not intersect the pivot point 276, the outer surface 262 can correspond to another form of spherical cap.

[0042] It will be appreciated that the nominal diameter D232 of the liner inner surface 232 can be slightly larger than the nominal diameter D224 of the insert outer surface 224, e.g., to ensure that the insert 220 remains pivotable relative to the liner 230, while allowing for variations in the diameters D224, D232 within manufacturing tolerances. In this case, each of the surfaces 262, 264 can still be considered to correspond to a spherical cap defined by the second sphere 266, and each of the diameters D224, D242 can still be considered to correspond to the diameter 268 of the sphere 266.

[0043] In certain embodiments, the first pivot point 275 and the second pivot point 276 can coincide with one another, such that the dual pivot 270 is provided as a single pivot point. However, in the illustrated embodiment, the second pivot point 276 is located on the end face plane 231’ of the liner 230, and the first pivot point 275 is slightly offset inboard relative to the second pivot point 276. In other words, the first pivot point 275 is slightly offset in the inboard direction from the second pivot point 276. Thus, the rotational orientation of the dual pivot 270 can change as the femoral component 110 is pivoted through its range of motion. More specifically, rotation of the liner 230 about the second pivot point 276 can cause the first pivot point 275 to move relative to the second pivot point 276. In contrast, the second pivot point 276 remains in a fixed position relative to the liner 230 mounted in the cup 120, and thus can be considered to define the location of the dual pivot 270. In other words, a description of the location of one of the dual pivot 270 and the second pivot point 276 can be understood equivalently as a description of the location of the other of the dual pivot 270 and the second pivot point 276.

[0044] Figure 2 The dual moving assembly 200 is shown in a starting position, with the insert inner apex 225 aligned with the head apex 215, and the insert outer apex 225’ aligned with the liner inner apex 245. When the dual moving assembly 200 is in the starting position and mounted to the cup 120, the liner outer apex 235 is also aligned with the cup inner apex 135. Unless otherwise indicated, a position or dimension description can be considered to describe the position or dimension when the dual moving assembly 200 is in the starting position and mounted to the cup 120. For example, a description of the head end face plane 211’ as being laterally offset from the liner end face plane 231’ should be understood to refer to the relative positions of the assembly 200 when in the original position. A person skilled in the art will readily appreciate that the end face planes 211’, 231’ can intersect one another when the assembly 200 is not in the starting position.

[0045] When the system 100 is assembled, the two articulation interfaces 250, 260 provided by the dual mobility assembly 200 facilitate pivoting of the femoral component 110 about the dual pivot 270 in two ways. More specifically, the first articulation interface 250 facilitates pivoting of the head 210 about a first pivot point 275 relative to the insert 220, and the second articulation interface 260 facilitates pivoting of the insert 220 about a second pivot point 276 relative to the liner 230. As described in further detail below, the modularity of the dual mobility assembly 200 enables certain characteristics of the system 100 to be adjusted while maintaining the same femoral component 110 and acetabular cup 120.

[0046] Reference is additionally made to Figure 4 A liner series 300 is shown therein that includes a plurality of liner varieties 310, 320, 330. In certain embodiments, the liner series 300 can be provided in a kit (e.g., the kit 700 described below with reference to Figure 8 The liner series can be provided as a standalone kit that is configured to be used with a cup 120 and an insert 220 having a predetermined configuration. Each of the liner varieties 310, 320, 330 can be selected as the liner 230 of the dual mobility assembly 200 and includes the features described above with reference to the liner 230. For the sake of brevity, the following description focuses primarily on features of the liner varieties 310, 320, 330 that differ from those described above with reference to the liner 230.

[0047] In the illustrated form, the liner series 300 includes a first liner variety 310, a second liner variety 320, and a third liner variety 330, each of which is configured to be seated in the cup 120 and to receive the insert 220. The liner varieties 310, 320, 330 are substantially similar to one another and differ primarily in certain dimensions thereof. For example, while the cavity height 243 of each of the liner varieties 310, 320, 330 defines a substantially identical liner cavity height 343, the apex thickness 244 of the first liner variety 310 is a first apex thickness 344, and the apex thickness 244 of the second and third liner varieties 320, 330 is a second apex thickness 344' that is different from the first apex thickness 344. More specifically, the second apex thickness 344' is greater than the first apex thickness 344 by a lateral offset distance 348. Thus, the effective height 242 of the first liner variety 310 is a first effective height 342, and the effective height 242 of each of the second and third liner varieties 320, 330 is a second effective height 342' that is greater than the first effective height 342 by the lateral offset distance 348. The first liner variety 310 can be considered to have a lateral offset distance of zero.

[0048] In some embodiments, the first effective height 342 may correspond to the depth dimension 133 of the cup cavity 123, and the second effective height 342ʹ may be larger than the depth dimension 133 by a predetermined distance. Additionally, while the second lining type 320 and the third lining type 330 have the same effective height 342ʹ, the third lining type 330 also includes a non-zero lateral offset distance 347 between the geometric axis 237 and its rotation axis 247. In some embodiments, the geometric axis 237 and rotation axis 247 of the first lining type 310 and the second lining type 320 may be considered to have a zero lateral offset distance.

[0049] For further reference Figures 5-7 and Figures 13-18 The modular nature of the dual-movement component 200 facilitates its use in each of several different configurations 201, 202, 203 within the system 100. For clarity, [the following has been described]... Figures 5-7 Some components of system 100, such as femoral component 110 and head 210, are omitted, but... Figures 13-18 As shown in the image.

[0050] Figure 5 , Figure 13 and Figure 14 The illustration shows a system 100 with the dual movement assembly 200 in a first configuration 201, wherein the liner 230 has a first liner type 310. In the illustrated form, the first effective height 342 is substantially equal to the depth dimension 133 of the cup cavity 123, and the liner cavity height 343 is substantially equal to half the diameter 268 of the second sphere 260. Therefore, the cup end face 121 is aligned with the liner end face 231, and the second pivot point 276 lies on the coplanar end face planes 121ʹ, 231ʹ. Furthermore, the central axis 127 of the cup 120 is aligned with the geometric axis 237 and the rotation axis 247 of the liner 230, such that the second pivot point 276 coincides with the reference point 126. Therefore, when the dual movement assembly 200 is configured in the first configuration 201, both the lateral and transverse offset distances of the dual pivots 270 relative to the reference point 126 are zero.

[0051] Figure 6 , Figure 15 and Figure 16 The illustration shows a system 100 with a dual-movement assembly 200 in a second configuration 202, wherein the liner 230 has a second liner type 320. In the illustrated embodiment, the second effective height 342ʹ is greater than the depth dimension 133 of the cup cavity 123, and the liner cavity height 343 is substantially equal to half the diameter 268 of the second sphere 260. Therefore, the second pivot point 276 is located on the liner end face plane 231ʹ, which in the lateral direction (in Figure 6The second pivot point 276 is located on the liner end face plane 231'which is offset from the cup end face plane 121'in the lateral direction (to the right in FIG. 2). Thus, when the dual mobile assembly 200 is set to the second configuration 202, the dual pivot 270 has a lateral offset distance 308 defined by the mid-lateral distance between the end face planes 121 ', 231 '. Additionally, the central axis 127 of the cup 120 is aligned with the geometric axis 237 and the rotational axis 247 of the liner 230. Thus, when the dual mobile assembly 200 is set to the second configuration 202, the lateral offset distance of the dual pivot 270 with respect to the reference point 126 is zero.

[0052] Figure 7 , Figure 17 and Figure 18 FIG. 2 illustrates the system 100 with the dual mobile assembly 200 in the third configuration 203, where the liner 230 has a third liner variety 330. As described above, the effective height 242 of the third liner variety 330 is a second effective height 342' and the cavity height 243 of the third liner variety 330 is a cavity height 343. In the illustrated embodiment, the second effective height 342' is greater than the depth dimension 133 of the cup cavity 123 and the cavity height 343 is substantially equal to one-half of the diameter 268 of the second sphere 260. Thus, the second pivot point 276 is located on the liner end face plane 231'which is offset from the cup end face plane 121'in the lateral direction (to the right in FIG. 2). Accordingly, when the dual mobile assembly 200 is set to the third configuration 203, the dual pivot 270 has a lateral offset dimension 308 corresponding to the mid-lateral distance between the end face planes 121 ', 231'of the cup 120 and the liner 230. Figure 7

[0053] When the dual mobile assembly 200 is in the third configuration 203, the rotational axis 247 is laterally offset from the geometric axis 237 which is aligned with the central axis 127 of the cup 120. Thus, the dual pivot 270 is laterally offset from the reference point 126 by a non-zero lateral offset dimension 307 corresponding to the lateral distance 347 between the geometric axis 237 and the rotational axis 247. As a result of the lateral offset dimension 307 and the lateral offset dimension 308, the line 339 extending between the reference point 126 and the second pivot point 276 defines an angle Θ339 with respect to the geometric axis 237 and the central axis 127.

[0054] ​While the illustrated liner series 300 includes three liner varieties 310, 320, 330, it should be appreciated that a liner series can include more or fewer liner varieties having additional or alternative configurations. For example, each liner variety within the liner series 300 can have a unique combination of values for the lateral offset distance 347 and the lateral offset distance 348, thereby providing different combinations of the lateral offset 307 and the lateral offset 308 for different configurations of the dual mobility assembly 200. In certain embodiments, the dual mobility assembly 200 can be provided as a kit including one or more component series. Each component series can include multiple component varieties having different properties (e.g., size, material, and / or finish). In such a form, the dual mobility assembly 200 can be assembled in each of multiple configurations, each configuration including a unique combination of selected component varieties.

[0055] Further reference is made to Figure 8 The dual mobility kit 700 according to certain embodiments includes a head series 710, an insert series 720, and a liner series 730. In the illustrated embodiment, the liner series 730 is provided in the form of the liner series 300 described above. The kit 700 is configured for use with the femoral component 110 and the acetabular cup 120, and can be used to form the dual mobility assembly 200 in each of multiple configurations having different properties.

[0056] The head series 710 includes multiple head varieties 712, 714, each of which is configured for use with the femoral component 110. Thus, each of the head varieties 712, 714 can be used as the head 210 of the dual mobility assembly 200. The head series 710 is configured to provide one or more variable properties for the head 210, and each head variety 712, 714 has a unique set of values for the one or more variable properties. In the illustrated embodiment, the first head variety 712 and the second head variety 714 have different outer diameters, such that the set of variable properties provided by the head series 710 includes the outer diameter of the head 210. For example, the first head variety 712 can have an outer diameter 713 of about 22 millimeters (mm), and the second head variety 714 can have an outer diameter 715 of about 28 mm. It is also contemplated that the head series 710 can include one or more additional or alternative variable properties, such as the material from which the head 210 is formed. As an example, one head variety can be formed from a ceramic material, while another head variety can be formed from a metallic material such as zirconia, diffusion hardened zirconia, or cobalt-chrome alloy.

[0057] The insert family 720 includes multiple insert varieties 722, 724, each of which can be used as the insert 220 of the dual mobility assembly 200. The insert family 720 is configured to provide one or more variable properties for the head insert 220, and each insert variety 722, 724 has a unique set of values for the one or more variable properties. In the illustrated embodiment, the first insert variety 722 and the second insert variety 724 have different inner diameters, such that the set of variable properties provided by the insert family 720 includes the inner diameter of the insert 220. As an example, the first insert variety 722 can have an inner diameter 723 of about 22 mm and be configured for use with the first head variety 712. Similarly, the second insert variety 724 can have an inner diameter 725 of about 28 mm and be configured for use with the second head variety 714. In the illustrated embodiment, each of the insert varieties 722, 724 has the same outer diameter. Thus, each of the insert varieties 722, 724 is configured for use with each of the liner varieties 310, 320, 330. It is also contemplated that the outer diameter of the insert 220 can be a variable property of the insert family 720. In such a form, the inner diameter of the liner 230 can be a variable property of the liner family 730.

[0058] As described above, the location of the first pivot point 275 within the insert 220 corresponds to the configuration of the inner surface 222, and the location of the second pivot point 276 within the insert 220 corresponds to the configuration of the outer surface 224. In certain embodiments, the relative locations of the first pivot point 275 and the second pivot point 276 can be a variable property of the insert family 720. For example, a first insert variety can have an offset distance 279 of zero, a second insert variety can have a first non-trivial offset distance, and a third insert variety can have a second non-trivial offset distance that is greater than the first non-trivial offset distance. Additionally or alternatively, the lateral and / or transverse components of the offset distance can differ from variety to variety.

[0059] In certain embodiments, the kit 700 can be configured for use with an existing femoral component 110 and / or an existing acetabular cup 120. For example, if a patient has previously undergone a partial or total hip replacement procedure in which a femoral component 110 and / or an acetabular cup 120 was implanted, it can be disadvantageous or harmful to remove the implanted components, for example in cases where significant bone ingrowth has occurred. In such cases, the dual mobility kit 700 can be used to establish a dual mobility assembly 200 for a revision procedure. Such a revision procedure can improve the performance of the hip joint without requiring removal of the previously implanted femoral component 110 and / or acetabular cup 120.

[0060] In other embodiments, such as where the system 100 is used for a primary hip replacement procedure, the dual mobility kit 700 can be provided in a kit of the system 100. Such a system kit can also include a femoral component 110 and / or an acetabular cup 120, or can include a series of femoral components and / or a series of acetabular cups of appropriate kinds from which the components 110 and / or cups 120 can be selected.

[0061] With continued reference to Figures 5-7 An exemplary use case scenario of the illustrated hip replacement system 100 and dual mobility assembly kit 700 will now be described. After the femoral component 110 and acetabular cup 120 have been implanted, the surgeon selects an initial configuration of the dual mobility assembly 200 based on patient information and professional judgment. For example, if a first joint interface diameter 258 of 22 mm is desired, the surgeon can initially select a head 210 of the first head kind 712, an insert 220 of the second insert kind 722, and a liner 230 of the first liner kind 310. The head 210 and insert 220 can then be releasably mounted to the femoral component 110 by inserting the head 210 into the insert cavity 223 and the tapered end 118 into the head cavity 213 such that the tapered walls 119, 219 engage one another. Additionally, the liner 230 can be releasably mounted in the cup 120 by inserting the liner 230 into the cup cavity 123 and engaging the cup inner surface 122 with the liner outer surface 234. The insert 220 can then be inserted into the liner cavity 233 to complete the provisional implantation of the system 100, with the dual mobility assembly 200 in the first configuration 201. Figure 5 、 Figure 13 and Figure 14 ).

[0062] After the provisional implantation of the system 100 is complete, the femur can be moved through a normal range of motion to assess the performance characteristics, such as kinematic and / or dynamic performance characteristics, of the reconstructed hip joint. In the event that the performance characteristics are deemed unsatisfactory, one or more of the modular components of the dual mobility assembly 200 can be replaced while the femoral component 110 and acetabular cup 120 remain implanted. The steps of reconfiguring the assembly 200 and assessing the provisionally implanted system 100 can be repeated as necessary until the desired performance characteristics are achieved. Once the performance characteristics of the hip joint are deemed satisfactory, the final implantation of the system 100 can be performed.

[0063] In certain embodiments, each component of the dual mobility assembly 200 is configured to function as both a trial component and a final component. In this form, the final implantation of the system 100 can include securing the head 210 to the femoral component 110 and securing the liner 230 to the cup 120. Such securing can involve, for example, the use of more permanent nature fixation devices, such as cements, self-locking features, and / or fasteners.

[0064] In other embodiments, one or more components of the dual mobility assembly 200 can be configured as trial components that are replaced with final components after the performance characteristics of the hip joint are deemed satisfactory. As one example, the above-described liner series 300 can be a series of trial liners, and the kit 700 can further include a series of final liners. Each of the trial liner varieties can be substantially similar to a corresponding one of the final liner varieties, while having one or more characteristics that are different from those of the corresponding final liner variety. For example, the trial liner varieties can lack certain features that make the corresponding final liner varieties suitable for final implantation, and / or the trial liner varieties can include certain features that facilitate the interchange of different varieties of trial liners. To illustrate, the final liners can include a self-locking feature that engages with the cup 120 and inhibits removal of the liner from the cup 120, and the trial liners can lack such a self-locking feature in order to facilitate removal of the trial liners when reconfiguring the assembly 200. In embodiments in which the assembly 200 includes both a series of trial components and a series of final components, the final implantation of the system 100 can include noting the variety of trial component that produces satisfactory performance characteristics, and replacing the noted variety of trial component with a final component of the corresponding variety of final component.

[0065] In an example use case scenario, the surgeon determines that the first configuration 201 of the dual mobility assembly 200 results in unsatisfactory or suboptimal performance characteristics of the system 100. More specifically, the surgeon determines that lateral excursion corresponding to the lateral excursion distance 308 is desirable for the dual pivot 270, and thus replaces the initially selected liner of the first variety 310 with a liner of the second variety 320. The criteria that can dictate that lateral excursion is desirable can include, for example, insufficient tension in the ligaments and / or other soft tissue. Such insufficient soft tissue tension can be a result of deterioration of the soft tissue and / or bone tissue in the vicinity of the hip joint as the acetabular socket has been expanded to a greater depth than indicated in the surgical plan or other anatomical and / or surgical conditions.

[0066] After replacing the liner of the first variety 310 with the liner of the second variety 320, the system 100 is temporarily implanted with the dual mobility assembly 200 in the second configuration 202 (Fig. 4B), and the surgeon determines that the performance characteristics of the system 100 are satisfactory. More specifically, the surgeon determines that the lateral excursion corresponding to the lateral excursion distance 308 is desirable for the dual pivot 270, and thus the second configuration 202 of the dual mobility assembly 200 is selected for final implantation of the system 100. Figure 6 Figure 15 and Figure 16 ​). After evaluating the performance characteristics of the hip joint, the surgeon can determine that a lateral offset dimension 307 is needed in addition to the lateral offset dimension 308, for example, in cases where additional soft tissue tension is needed. In this case, the surgeon can select a liner of the third class 330 to replace the previously selected liner of the second class 320. The surgeon can then estimate the optimal orientation of the lateral offset 307 relative to the patient's anatomy and insert the liner 230 into the cup 120 with the corresponding rotational orientation. The system 100 is then reassembled with the dual mobility assembly 200 in the third configuration 203 (FIG. 3C) and the performance of the hip joint is reevaluated. Figure 7 , Figure 17 and Figure 18 ) the system 100 is reassembled with the dual mobility assembly 200 in the third configuration 203 (FIG. 3C) and the performance of the hip joint is reevaluated.

[0067] If the surgeon determines that a different orientation of the lateral offset dimension 307 can lead to improved performance characteristics, the liner 230 can be removed from the cup 120 and reinserted with the new rotational orientation. In other words, by removing the liner 230 from the cup 120, rotating the liner 230 about the geometric axis 237, and reinserting the liner 230 in the new rotational position, the dual pivot 270 can be rotated about the central axis 127 of the cup 120.

[0068] As noted above, the dual mobility assembly 200 can be provided as a kit 700 that is configured to be used with an existing femoral component 110 and / or an existing acetabular cup 120. Figure 9 , Figure 10 and Figure 19 An example of a liner 430 that can be included in such a kit is shown. The liner 430 is substantially similar to the liner 230 described above, and like reference numerals are used to indicate like elements and features. The liner 430 also includes certain elements and features 470 that are not necessarily included in the liner 230 and / or that were not specifically described above. For the sake of brevity, the following description of the liner 430 focuses primarily on these elements and features 470.

[0069] The liner 430 includes an inner layer 472 that defines an inner articulating surface 432 and an outer layer 474 that defines an outer surface 434. The inner layer 472 is formed from a first material, and the outer layer 474 is formed from a second material. In the illustrated form, the inner layer 472 is formed from a metal, and the outer layer 474 is formed from a polymer (e.g., cross-linked polyethylene), although other materials are contemplated. The inner layer 472 and the outer layer 474 include mating features 473 that help to secure the layers 472, 474 to one another. In certain embodiments, the liner 430 can be formed by molding the outer layer 474 onto the inner layer 472. In other embodiments, the layers 472, 474 can be formed separately, and the inner layer 472 can be press-fit into the outer layer 474.

[0070] The liner 430 is configured to be used with an existing acetabular cup 420 that can have been implanted in a patient during a prior surgical procedure. The liner 430 includes a rim 471 that defines a liner end face 431 and a locking ring 475 formed "above" (i.e., medially of) the rim 471. The locking ring 475 is configured to engage a corresponding locking ring 425 formed in the cup 420 adjacent to its end face 421. More specifically, each of the locking rings 425, 475 includes a series of recesses and protrusions that engage one another to at least partially secure the liner 430 to the cup 420. When the liner 430 is inserted into the cup 420 and the locking rings 425, 475 engage one another, the rim 471 extends laterally beyond the cup end face 421 such that the liner end face plane 431' is positioned "below" (i.e., laterally of) the cup end face plane 421'. Thus, the liner 430 is able to provide a pivot point 479 having a neutral lateral offset that corresponds to the lateral offset 308 provided by the second liner variety 320 and the third liner variety 330.

[0071] In certain embodiments, the dual mobility assembly 200 can be provided as a revision kit configured to be used with the cup 420, e.g., if the cup 420 was previously implanted in a patient. Such a revision kit can include a liner family that includes multiple liner varieties similar to the liner 430. Similar to the second liner variety 320, the liner 430 is configured to provide a lateral offset without providing a transverse offset. Those skilled in the art will readily appreciate that the dimensions of the liner 430 can be modified to create additional liner varieties that correspond to the first liner variety 310 and the third liner variety 330 described above.

[0072] Figure 11 An adapter ring 500 is illustrated in accordance with certain embodiments. The adapter ring 500 is configured to be used with the cup 420 and the liner 230 of the first variety 310. More specifically, the adapter ring 500 is configured to provide the first liner variety 310 with a lateral offset 548 that corresponds to the lateral offset 348 provided by the second liner variety 320. The adapter ring 500 includes a locking ring 510, a rim 520 laterally positioned of the locking ring 510, and a tapered inner surface 530. The locking ring 510 is configured to engage the locking ring 425 of the cup 420 in a manner similar to the locking ring 475 of the liner 430. The rim 520 has a medial width 522 that is sized such that an end face plane 521' of the adapter ring 500 is laterally offset from the end face plane 421' of the cup 420.

[0073] The conical inner surface 530 is configured to engage the conical outer surface 234T to prevent the liner 230 from seating completely in the cup 420. Thus, the end face 231 of the liner 230 is offset in the lateral direction from the end face 421 of the cup 420. Accordingly, the adapter ring 500 enables the first liner variety 310 to be used with a conventional cup 420 while providing the lateral offset 548 for the second pivot point 276. The lateral offset distance 548 provided by the adapter ring can be adjusted by selecting an adapter ring variety having a greater or lesser mid-side width 522. Additionally or alternatively, the lateral offset size 548 can be adjusted by selecting an adapter ring variety in which the conical inner surface 530 has the same conical angle but a greater or lesser diameter at its end face.

[0074] Figure 12 is a cross-sectional illustration of the acetabular cup 120 described above and illustrates various features 600 of the cup 120 not specifically described above. For the sake of brevity, the following description of the cup 120 focuses primarily on these elements and features 600. The cup 120 includes an inner layer 612 that defines the inner surface 122 and an outer layer 614 that defines the outer surface 124. The inner layer 612 can be provided as a substantially solid layer, and the outer layer 614 can be porous to facilitate bone ingrowth. In certain embodiments, the inner layer 612 can be polished to provide the inner surface 122 with a substantially smooth finish.

[0075] The inner surface 122 includes a plurality of outwardly extending sectors 622, a tapered wall 626 positioned "above" (i.e., medial to) the end face 121, a curved wall 628 positioned medial to the tapered wall 626, and a locking feature 630 between the tapered wall 626 and the curved wall 628. The tapered wall 626 has a geometry that corresponds to that of the tapered wall 122T such that the tapered walls 122T, 626 can be flushly engaged with one another. The sectors 622 are formed adjacent to the end face 121 and are connected to the end face opening 131. The inner surface 122 also includes an annular channel 624 that diverges from the end face 121 medially and intersects the sectors 622. The tapered wall 626 is symmetrical about the central axis 127 and defines a predetermined taper angle Θ626. In the illustrated form, the predetermined taper angle Θ626 is about 18° such that the tapered wall 626 defines an angle of about 9° with respect to the central axis 127. In the illustrated form, the curved wall 628 is a spherical cap, e.g., a cap of a sphere, centered on the reference point 126 and having a radius that corresponds to the cavity depth 133.

[0076] The locking feature 630 includes a lateral or lower groove 632, a medial or upper groove 634, and a protrusion 636 between the grooves 632, 634. The locking feature 630 can also include a wall 638 extending between the tapered wall 626 and the lower groove 632 and can be disposed parallel to the central axis 127. As noted above, the liner 230 can be provided as a final liner or a trial liner. The final liner can include corresponding locking features configured to engage the locking feature 630 such that the engaged locking features form a self-locking mechanism that inhibits removal of the final liner from the cup 120. By way of example, such corresponding locking features can include a lower nub configured to be received in the lower groove 632, an upper nub configured to be received in the upper groove 634, and a recess configured to receive the protrusion 636. In contrast, one or more of the corresponding locking features can be omitted from the trial liner, making the trial liner easier to remove from the cup 120.

[0077] The cup 120 can also include one or more fixation features 640 to facilitate fixation of the cup 120 to a hip joint within a prepared acetabular socket. In the illustrated form, each fixation feature 640 includes an inverse slot 642 recessed relative to the inner surface 132 and a star-shaped opening 644 formed within the inverse slot 642. After the cup 120 is initially implanted into the acetabular socket, the fixation features 640 can cooperate with fasteners to secure the cup 120 within the socket. For example, a shank of a fastener can extend through the opening 644 and engage the femur, and a head of the fastener can be received in the inverse slot 642 to prevent the fastener from impinging on the liner 230.

[0078] One embodiment of the present application is directed to a system including a cup configured for implantation into an acetabular socket, and a dual mobility assembly defining a dual pivot including a first pivot point and a second pivot point. The cup defines a geometric axis including a medial direction and an opposite lateral direction, and includes a cup face extending along a cup face plane and defining a cup opening, a cup apex positioned medially of the cup face, wherein the geometric axis extends through the cup apex and intersects the cup face plane at a reference point, and a cup inner surface defining a cup cavity connected with the cup opening, wherein the cup inner surface includes a tapered wall centered about the geometric axis, wherein the tapered wall tapers radially inward in the medial direction. The dual mobility assembly includes a liner positioned in the cup cavity, the liner including a liner outer surface and a liner inner surface, wherein the liner outer surface includes a tapered portion engaged with the tapered wall of the cup and centered about the geometric axis, and wherein the liner inner surface defines a liner cavity and is spherical about the second pivot point, an insert positioned in the liner cavity, the insert including an insert outer surface and an insert inner surface, wherein the insert outer surface is spherical about the second pivot point, and wherein the insert inner surface defines an insert cavity and is spherical about the first pivot point, and a head positioned in the insert cavity, the head including a head outer surface and a head inner surface, wherein the head outer surface is spherical about the first pivot point, and wherein the head inner surface defines a head cavity sized and configured to receive a portion of a femoral component. The dual mobility assembly is adjustable between a plurality of configurations including a first configuration and a second configuration. When the dual mobility assembly is in the first configuration, the liner has a first liner species and the second pivot point has a first position relative to the reference point. When the dual mobility assembly is in the second configuration, the liner has a second liner species and the second pivot point has a second position relative to the reference point. The first position is different than the second position, and at least one of the first position or the second position is offset from the reference point in the lateral direction.

[0079] In certain forms, at least one of the first position or the second position is offset from the geometric axis in a direction transverse to the geometric axis.

[0080] In certain forms, each of the first position and the second position is offset from the reference point in the lateral direction.

[0081] In certain forms, the first position is on the geometric axis, and wherein the second position is offset from the geometric axis in a direction transverse to the geometric axis.

[0082] In certain forms, the first position coincides with the reference point, and wherein the second position is offset from the reference point in the lateral direction.

[0083] In certain forms, the liner inner surface and the insert outer surface define an outer articulation interface having an outer articulation interface diameter, and wherein the insert inner surface and the head outer surface define an inner articulation interface having an inner articulation interface diameter. In one refinement, the insert has a first insert genus when the dual mobility assembly is in the first configuration, the outer articulation interface diameter has an outer articulation interface diameter first value, and the inner articulation interface has an inner articulation interface diameter first value; wherein the insert has a second insert genus when the dual mobility assembly is in the second configuration, the outer articulation interface diameter has an outer articulation interface diameter second value, and the inner articulation interface has an inner articulation interface diameter second value; and wherein at least one of the following is true: (i) the outer articulation interface diameter first value is different from the outer articulation interface diameter second value; or (ii) the inner articulation interface diameter first value is different from the inner articulation interface diameter second value.

[0084] In certain forms, the first configuration is a first trial configuration, and the second configuration is a second trial configuration; wherein the first liner genus is a first trial liner genus, and the second liner genus is a second trial liner genus; wherein the plurality of configurations further includes a first final configuration and a second final configuration, in the first final configuration the liner has a first final liner genus, and the second pivot point has a first position relative to the reference point, in the second final configuration the liner has a second final liner genus, and the second pivot point has a second position relative to the reference point; wherein each of the trial liner genera includes a first set of features that facilitate adjusting the dual mobility assembly between the first trial configuration and the second trial configuration; and wherein each of the final liner genera includes a second set of features that facilitate fixing the dual mobility assembly in the first final configuration and the second final configuration.

[0085] Another embodiment of the present application relates to a system comprising a cup, a femoral component, and a dual mobility assembly. The cup is configured for implantation into a acetabular socket, the cup comprising a cup outer surface and a cup inner surface defining a cup cavity, the cup having a hemispherical geometry with a cup center point, a cup apex offset in a medial direction from the cup center point, and a geometric axis extending through the cup center point and the cup apex, and the geometric axis defining a medial direction and a lateral direction opposite the medial direction. The femoral component is configured for implantation into a femur. The dual mobility assembly comprises a first articulating interface centered about a first pivot point, a second articulating interface centered about a second pivot point, and a dual pivot comprising the first pivot point and the second pivot point, wherein at least one of the first pivot point or the second pivot point is offset in the lateral direction from the cup center point such that the dual pivot is at least partially outside the cup cavity, wherein the dual mobility assembly is installed between the cup and the femoral component such that the cup and the femoral component are pivotable relative to each other about the dual pivot. The dual mobility assembly comprises a head portion installed to the femoral component, the head portion comprising a head portion inner surface and a head portion outer surface, wherein the head portion inner surface is engaged with the femoral component, and wherein the head portion outer surface is centered about the first pivot point and partially defines the first articulating interface, a liner positioned within the cup cavity, the liner comprising a liner outer surface and a liner inner surface, wherein the liner outer surface is engaged with the cup inner surface, and wherein the liner inner surface is centered about the second pivot point and partially defines the second articulating interface, and an insert positioned between the head portion and the liner, the insert comprising an insert inner surface and an insert outer surface, wherein the insert inner surface is centered about the first pivot point and further defines the first articulating interface, and wherein the insert outer surface is centered about the second pivot point and further defines the second articulating interface.

[0086] In certain forms, the second pivot point is offset in the lateral direction from the cup center point.

[0087] In certain forms, the second pivot point is offset in the lateral direction from the cup center point, and the first pivot point is offset in the lateral direction from the cup center point.

[0088] In certain forms, the second pivot point is offset in the lateral direction from the cup center point, the first pivot point is offset in the lateral direction from the cup center point, and the first pivot point is offset in the medial direction from the second pivot point.

[0089] In certain forms, the second pivot point is offset from the cup center point in the lateral direction, the first pivot point is offset from the cup center point in the lateral direction, and the second pivot point is offset from the cup center point in a direction transverse to the geometric axis.

[0090] Another embodiment of the present application is directed to a system including a cup and a plurality of liners. The cup is configured for implantation into an acetabular socket, the cup having a cup geometric axis defining a medial direction and an opposing lateral direction, and the cup including: a cup face extending along a cup face plane and defining a cup opening; a cup apex positioned medial of the cup face, wherein the cup geometric axis extends through the cup apex and intersects the cup face plane at a reference point; and a cup inner surface defining a cup cavity connected with the cup opening, wherein the cup inner surface includes a tapered wall centered about the cup geometric axis, wherein the tapered wall tapers radially inward in the medial direction. Each of the plurality of liners is configured to be positioned in the cup cavity, and each liner includes: a liner geometric axis, wherein the liner geometric axis is aligned with the cup geometric axis when the liner is positioned in the cup cavity; a liner outer surface including a tapered portion configured to engage the tapered wall, wherein the tapered portion is centered about the liner geometric axis; a liner inner surface centered about a first pivot point and having a liner inner diameter, the liner inner surface defining a liner cavity; a transverse offset dimension defined between the first pivot point and the liner geometric axis; and an effective height, wherein the first pivot point is offset from the cup apex by the effective height in the lateral direction when the liner is positioned in the cup cavity. A first liner of the plurality of liners has a first transverse offset dimension and a first effective height, wherein the first pivot point has a first position relative to the reference point when the first liner is positioned in the cup cavity. A second liner of the plurality of liners has a second effective height greater than the first effective height, wherein the first pivot point has a second position relative to the reference point when the second liner is positioned in the cup cavity, and wherein a third position is offset from the reference point in the lateral direction. A third liner of the plurality of liners has a second transverse offset dimension greater than the first transverse offset dimension, wherein the first pivot point has a third position relative to the reference point when the third liner is positioned in the cup cavity, and wherein the third position is not located on the cup geometric axis.

[0091] In certain forms, the first transverse offset dimension is zero, such that the first position is located on the cup geometric axis.

[0092] In certain forms, the second liner has a first lateral offset dimension, and wherein the third liner has a second effective height.

[0093] In certain forms, the system further comprises a plurality of inserts; wherein each insert comprises: an insert outer surface having a spherical geometry, the insert outer surface centered about the first pivot point when the insert is positioned in the liner cavity; and an insert inner surface centered about a second pivot point and having an insert inner diameter; wherein a first one of the inserts has a first insert inner diameter, and a second one of the inserts has a second insert inner diameter greater than the first insert inner diameter. In an improvement, the system further comprises a plurality of heads; wherein each head comprises: a head inner surface defining a head cavity sized and shaped to receive a portion of a femoral component; and a head outer surface having a head outer diameter; wherein a first one of the heads has a first head outer diameter corresponding to the first insert inner diameter, and wherein a second one of the heads has a second head outer diameter corresponding to the second insert inner diameter.

[0094] Another embodiment of the present application relates to a system including a cup configured for implantation into an acetabular socket, and a dual mobility assembly defining a dual pivot including a first pivot point and a second pivot point. The cup defines a geometric axis including a medial direction and an opposite lateral direction, the cup including a cup face extending along a cup face plane and defining a cup opening, a cup apex positioned medially within the cup face, wherein the geometric axis extends through the cup apex and intersects the cup face plane at a reference point, and a cup inner surface defining a cup cavity connected with the cup opening, wherein the cup inner surface includes a tapered wall centered about the geometric axis, wherein the tapered wall tapers radially inward in the medial direction. The dual mobility assembly includes a liner positioned within the cup cavity, the liner including a liner outer surface and a liner inner surface, wherein the liner outer surface includes a tapered portion engaged with the tapered wall of the cup and centered about the geometric axis, and wherein the liner inner surface defines a liner cavity and is spherical about the second pivot point, an insert positioned within the liner cavity, the insert including an insert outer surface and an insert inner surface, wherein the insert outer surface is spherical about the second pivot point, and wherein the insert inner surface defines an insert cavity and is spherical about the first pivot point, and a head positioned within the insert cavity, the head including a head outer surface and a head inner surface, wherein the head outer surface is spherical about the first pivot point, and wherein the head inner surface defines a head cavity sized and configured to receive a portion of a femoral component. The dual mobility assembly is adjustable between a plurality of configurations including a first configuration and a second configuration. In the first configuration of the dual mobility assembly, the liner has a first liner species and the second pivot point has a first position relative to the reference point. In the second configuration of the dual mobility assembly, the liner has a second liner species and the second pivot point has a second position relative to the reference point. The first position is different than the second position, and at least one of the first position or the second position is offset from the reference point in the lateral direction.

[0095] In certain forms, the cup has a hemispherical geometric shape centered at the reference point.

[0096] In certain forms, at least one of the first position or the second position is offset from the geometric axis in a direction transverse to the geometric axis.

[0097] In certain forms, each of the first position and the second position is offset from the reference point in the lateral direction.

[0098] In certain forms, the first location is on the geometric axis, and the second location is offset from the geometric axis in a direction transverse to the geometric axis.

[0099] In certain forms, the first location coincides with the reference point, and wherein the second location is offset from the reference point in the lateral direction.

[0100] In certain forms, the first pivot point is offset from the reference point in the lateral direction, and the second pivot point is offset from the first pivot point in the lateral direction, when the dual movement assembly is in the first configuration.

[0101] In certain forms, the first pivot point is offset from the geometric axis in a direction transverse to the geometric axis, when the dual movement assembly is in the first configuration.

[0102] In certain forms, the first pivot point is offset from the reference point in the medial direction, when the dual movement assembly is in the first configuration.

[0103] In certain forms, the liner inner surface and the insert outer surface define an outer joint interface having an outer joint interface diameter, and the insert inner surface and the head outer surface define an inner joint interface having an inner joint interface diameter.

[0104] In certain forms, the insert has a first insert genus, the outer joint interface diameter has an outer joint interface diameter first value, and the inner joint interface has an inner joint interface diameter first value, when the dual movement assembly is in the first configuration; wherein the insert has a second insert genus, the outer joint interface diameter has an outer joint interface diameter second value, and the inner joint interface has an inner joint interface diameter second value, when the dual movement assembly is in the second configuration; and wherein at least one of the following is true: (i) the outer joint interface diameter first value is different from the outer joint interface diameter second value; or (ii) the inner joint interface diameter first value is different from the inner joint interface diameter second value.

[0105] In certain forms, the inner joint interface diameter first value is different from the inner joint interface diameter second value; wherein the head has a first head genus, and each of the insert inner surface and the head outer surface has a diameter corresponding to the inner joint interface diameter first value, when the dual movement assembly is in the first configuration; and wherein the head has a second head genus, and each of the insert inner surface and the head outer surface has a diameter corresponding to the inner joint interface diameter second value, when the dual movement assembly is in the second configuration.

[0106] In certain forms, the first configuration is a first trial configuration, and the second configuration is a second trial configuration; wherein the first liner variety is a first trial liner variety, and the second liner variety is a second trial liner variety; wherein the plurality of configurations further comprises a first final configuration and a second final configuration, in the first final configuration the liner has a first final liner variety, and the second pivot point has a first position relative to the reference point, in the second final configuration the liner has a second final liner variety, and the second pivot point has a second position relative to the reference point; wherein each of the trial liner varieties comprises a first set of features that facilitate adjustment of the dual mobility assembly between the first trial configuration and the second trial configuration; and wherein each of the final liner varieties comprises a second set of features that facilitate fixation of the dual mobility assembly in the first final configuration and the second final configuration.

[0107] In certain forms, the system further comprises a femoral component comprising a body and a neck extending at an angle relative to the body, wherein an end of the neck is received in the head cavity such that the cup and the femoral component are pivotable relative to one another about the dual pivot.

[0108] In certain forms, the cup inner surface comprises a circumferential groove positioned inside the tapered wall; wherein the liner outer surface comprises a circumferential ridge positioned inside the tapered portion; and wherein the groove and the ridge engage one another and resist relative movement of the cup and the liner along the geometric axis.

[0109] While the application has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the application are desired to be protected.

[0110] It should be understood that while the use of words such as "preferably," "preferably," "preferred," or "more preferred" in the description above indicates that the feature so described can be more desirable, it can not be necessary, and embodiments lacking the same can be considered to be within the scope of the present application, the scope of which is defined by the claims below. In reading claims, where words such as "a," "an" and "at least one" are used to denote a singular term or phrase, the intention is to cover both the singular noun or phrase, and plural referents unless specifically indicated to the contrary in the claim language. The use of the language "at least one" and / or "a" or "an" when used to describe a feature or features in the claims is intended to cover the full range of features both singular and plural unless otherwise indicated by the claim language.

Claims

1. A modular dual mobility hip joint system for total hip arthroplasty, comprising: a femoral component (110) configured for implantation in a femur; a cup (120) configured for implantation in an acetabular socket, wherein the cup has a geometric axis defining a medial direction and an opposite lateral direction, wherein the cup comprises: a cup face extending along a cup face plane and defining a cup opening; a cup apex positioned medially of the cup face, wherein the geometric axis extends through the cup apex and intersects the cup face plane at a reference point; and a cup inner surface defining a cup cavity connected with the cup opening; and a dual mobility assembly defining a dual pivot comprising a first pivot point and a second pivot point, the dual mobility assembly configured for insertion into the cup cavity, the dual mobility assembly comprising: a liner (230) mounted in the cup (120) and comprising a liner outer surface and a liner inner surface, wherein the liner inner surface defines a liner cavity and is spherical about the second pivot point; an insert (220) positioned in the liner cavity and mounted between the liner (230) and a head (210), the insert comprising an insert outer surface and an insert inner surface, wherein the insert outer surface is spherical about the second pivot point (276), and wherein the insert inner surface defines an insert cavity and is spherical about the first pivot point (275); and a head (210) positioned in the insert cavity and mounted to the femoral component (110), the head comprising a head outer surface and a head inner surface, wherein the head outer surface is spherical about the first pivot point, and wherein the head inner surface defines a head cavity sized and configured to receive a portion of a femoral component; wherein the dual mobility assembly is adjustable between a plurality of configurations, the plurality of configurations comprising a first configuration and a second configuration; wherein, when the dual mobility assembly is in the first configuration, the liner has a first liner species and the second pivot point has a first position relative to the reference point; wherein, when the dual mobility assembly is in the second configuration, the liner has a second liner species and the second pivot point has a second position relative to the reference point; and wherein the first position is different from the second position, and wherein at least one of the first position or the second position is offset from the reference point in the lateral direction. The dual movement assembly (200) provides a first articulation interface (250) defined between the head (210) and the insert (220) and facilitating relative pivotal movement of the head (210) and the insert (220) about a first pivot point (275), and a second articulation interface (260) defined between the insert (220) and the liner (230) and facilitating relative pivotal movement of the insert (220) and the liner (230) about a second pivot point (276).

2. The system of claim 1, wherein, The cup has a hemispherical geometry centered on the reference point.

3. The system of claim 1 or 2, wherein, At least one of the first position or the second position is offset from the geometric axis in a direction transverse to the geometric axis.

4. The system of claim 1 or 2, wherein, Each of the first position and the second position is offset from the reference point in the lateral direction.

5. The system of claim 1 or 2, wherein, The first position is on the geometric axis, and wherein the second position is offset from the geometric axis in a direction transverse to the geometric axis.

6. The system of claim 1 or 2, wherein, The first position coincides with the reference point, and wherein the second position is offset from the reference point in the lateral direction.

7. The system of claim 1 or 2, wherein, When the dual movement assembly is in the first configuration, the first pivot point is offset from the reference point in the lateral direction, and the second pivot point is offset from the first pivot point in the lateral direction.

8. The system of claim 1 or 2, wherein, When the dual movement assembly is in the first configuration, the first pivot point is offset from the geometric axis in a direction transverse to the geometric axis.

9. The system of claim 1 or 2, wherein, When the dual movement assembly is in the first configuration, the first pivot point is offset from the reference point in the medial direction.

10. The system of claim 1 or 2, wherein, The liner inner surface and the insert outer surface define an outer articulation interface having an outer articulation interface diameter, and wherein the insert inner surface and the head outer surface define an inner articulation interface having an inner articulation interface diameter.

11. The system of claim 10, wherein, When the dual movement assembly is in the first configuration, the insert has a first insert genus, the outer articulation interface diameter has an outer articulation interface diameter first value, and the inner articulation interface has an inner articulation interface diameter first value; wherein, when the dual movement assembly is in the second configuration, the insert has a second insert genus, the outer articulation interface diameter has an outer articulation interface diameter second value, and the inner articulation interface has an inner articulation interface diameter second value; and wherein at least one of the following holds: (i) the outer articulation interface diameter first value is different from the outer articulation interface diameter second value; or (ii) the inner articulation interface diameter first value is different from the inner articulation interface diameter second value.

12. The system of claim 11, wherein, The inner articulation interface diameter first value is different than the inner articulation interface diameter second value; wherein, when the dual mobility assembly is in the first configuration, the head has a first head genus and each of the insert inner surface and the head outer surface has a diameter corresponding to the inner articulation interface diameter first value; and wherein, when the dual mobility assembly is in the second configuration, the head has a second head genus and each of the insert inner surface and the head outer surface has a diameter corresponding to the inner articulation interface diameter second value.

13. The system of claim 1 or 2, wherein, The first configuration is a first trial configuration and the second configuration is a second trial configuration; wherein the first liner genus is a first trial liner genus and the second liner genus is a second trial liner genus; wherein the plurality of configurations further comprises a first final configuration and a second final configuration, in the first final configuration the liner has a first final liner genus and the second pivot point has a first position relative to the reference point, in the second final configuration the liner has a second final liner genus and the second pivot point has a second position relative to the reference point; wherein each of the trial liner genera comprises a first set of features that facilitate adjustment of the dual mobility assembly between the first trial configuration and the second trial configuration; and wherein each of the final liner genera comprises a second set of features that facilitate fixation of the dual mobility assembly in the first final configuration and the second final configuration.

14. The system of claims 1 or 2, further comprising a femoral component comprising a body and a neck extending at an angle relative to the body, wherein, An end of the neck is received in the head cavity such that the cup and the femoral component can be pivoted relative to each other about the dual pivot.

15. The system of claim 1 or 2, wherein, The liner outer surface comprises a protrusion. The liner outer surface comprises a protrusion.

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