A device for installing the acetabular liner into the acetabular cup.

Abstract

The acetabular prosthesis assembly includes an acetabular shell (100) component and an acetabular bearing component (10). The shell component includes a concave inner wall (112) having a tapered surface (118) with a plurality of anti-rotation slots (134) defined therein. The bearing component includes a convex outer wall (26), an annular flange (30), and a plurality of anti-rotation keys (32) extending radially outward from the outer wall. When the anti-rotation keys are positioned in rotational alignment with the anti-rotation slots, the flange of the bearing component is positioned in contact with the tapered surface of the shell component. When the anti-rotation keys are positioned out of rotational alignment with the anti-rotation slots, the flange is spaced from the tapered surface. A method of assembling the acetabular prosthesis assembly is also disclosed.

Description

[[TECHNICAL FIELD]]

[0001] The present disclosure generally relates to orthopedic surgical implants, and more specifically relates to modular orthopedic surgical implant systems. [[BACKGROUND ART]]

[0002] Arthroplasty is a well-known surgical procedure in which diseased and / or damaged biological joints are replaced with artificial joints. For example, in a hip arthroplasty surgical procedure, the acetabular joint of the patient's natural hip is partially or fully replaced with an artificial hip joint. A typical artificial hip joint includes an acetabular prosthesis component and a femoral head prosthesis component. The acetabular prosthesis component generally has an outer shell or cup configured to engage with the patient's acetabulum, and an inner bearing or liner coupled to the shell and configured to engage with the femoral head. The femoral head prosthesis component and the inner bearing of the acetabular component form an acetabular joint close to a natural hip joint. [[SUMMARY OF THE INVENTION]] [[MEANS FOR SOLVING THE PROBLEM]]

[0003] According to one embodiment, the acetabular prosthesis assembly comprises an acetabular shell component configured to be implanted in a patient's surgically prepared acetabulum, and a polymer acetabular bearing component configured to be received by the acetabular shell component. The acetabular shell component includes an annular rim and a concave inner wall extending inward from the annular rim, the concave inner wall having a tapered surface with a plurality of anti-rotation slots defined. The acetabular bearing component includes an annular rim and a convex outer wall extending inward from the annular rim to its apex, an annular flange extending radially outward from the outer wall, and a plurality of anti-rotation keys extending radially outward from the outer wall. When the plurality of anti-rotation keys are positioned in rotational alignment with the plurality of anti-rotation slots, the flange of the acetabular bearing component is positioned in contact with the tapered surface of the acetabular shell component. When the plurality of anti-rotation keys are positioned without rotational alignment with the plurality of anti-rotation slots, the flange of the acetabular bearing component is spaced apart from the tapered surface of the acetabular shell component.

[0004] In one embodiment, when multiple anti-rotation keys are positioned without rotational alignment with multiple anti-rotation slots, the inner surface of each of the multiple anti-rotation keys is positioned in contact with the annular rim of the acetabular shell component. In one embodiment, when multiple anti-rotation keys are positioned with rotational alignment with multiple anti-rotation slots, the inner surface of each of the multiple anti-rotation keys is positioned within the corresponding anti-rotation slot among the multiple anti-rotation slots. In one embodiment, when multiple anti-rotation keys are positioned with rotational alignment with multiple anti-rotation slots, the inner surface of each of the multiple anti-rotation keys is positioned a predetermined distance inward from the annular rim of the acetabular shell component. In one embodiment, the predetermined distance is 0.5 mm.

[0005] In one embodiment, multiple anti-rotation keys are evenly spaced around the annular rim of the acetabular bearing component.

[0006] In one embodiment, when a plurality of anti-rotation keys are positioned in rotational alignment with a plurality of anti-rotation slots and the acetabular bearing component is fully installed within the acetabular shell component, each of the plurality of anti-rotation keys is positioned within a corresponding anti-rotation slot among the plurality of anti-rotation slots. In one embodiment, when a plurality of anti-rotation keys are positioned in rotational alignment with a plurality of anti-rotation slots and the acetabular bearing component is fully installed within the acetabular shell component, the flange is received in an annular groove defined in the concave inner wall of the acetabular shell component.

[0007] In one embodiment, the outer wall of the acetabular bearing component includes a tapered surface extending inward from the annular rim. In one embodiment, each of the plurality of anti-rotation keys includes an outer wall fused to the tapered surface. In one embodiment, the plurality of anti-rotation keys extend radially outward from the tapered surface. In one embodiment, the outer wall of the acetabular bearing component includes a curved relief surface located between the tapered surface and the flange, the curved relief surface extending radially inward from the tapered surface and the flange.

[0008] In one embodiment, the tapered surface of the acetabular shell component defines a taper angle, and the flange of the acetabular bearing component includes a flange surface that defines a flange angle. The flange angle is greater than or equal to the taper angle. In one embodiment, the taper angle is 10° and the flange angle is 10-14°. In one embodiment, the flange angle is 12°.

[0009] In another embodiment, a method for implanting an acetabular prosthesis is to implant an acetabular shell component into a surgically prepared acetabulum of a patient, the acetabular shell component comprising an annular rim and a concave inner wall extending inward from the annular rim, the concave inner wall having a tapered surface with a plurality of anti-rotation slots defined, and in response to implantation and insertion of the acetabular shell component, an acetabular bearing component being moved to contact the implanted acetabular shell component, the acetabular bearing component comprising (i) an annular rim, (ii) a convex outer wall extending inward from the annular rim to the apex, and (iii) an annular flange extending radially outward from the outer wall, iv) Moving and rotating an acetabular bearing component, which includes a plurality of anti-rotation keys extending radially outward from the outer wall, from a first position in which the plurality of anti-rotation keys are located without rotational alignment with the plurality of anti-rotation slots relative to an embedded acetabular shell component, to a second position in which the plurality of anti-rotation keys are located with rotational alignment with the plurality of anti-rotation slots, wherein when in the first position, the flange of the acetabular bearing component is spaced apart from the tapered surface of the acetabular shell component, and when in the second position, the flange of the acetabular bearing component is located in contact with the tapered surface of the acetabular shell component.

[0010] In one embodiment, the method further includes inserting the acetabular bearing component into an embedded acetabular shell component when the acetabular bearing component is in a second position.

[0011] In one embodiment, inserting the acetabular bearing component includes deforming the flange of the acetabular bearing component. In one embodiment, the method further includes receiving the flange of the acetabular bearing component into an annular groove defined in the concave inner wall of the acetabular shell component. In one embodiment, receiving the flange into the annular groove includes elastically relaxing the flange to its original shape. In one embodiment, receiving the flange into the annular groove includes engaging the tapered surface of the acetabular bearing component with the tapered surface of the acetabular shell component. [Brief explanation of the drawing]

[0012] For a detailed explanation, please refer specifically to the following diagrams. [Figure 1] This is a perspective view of the acetabular bearing component of an acetabular prosthesis implant. [Figure 2] This is a cross-sectional view in the front-to-back direction along line 2-2 in Figure 1, as seen in the direction of the arrow. [Figure 3] Figure 2 is a detailed view of the cross-section. [Figure 4] This is a perspective view of the acetabular shell component of an acetabular prosthesis implant. [Figure 5] This is a cross-sectional view in the front-to-back direction along line 5-5 in Figure 4, as seen in the direction of the arrow. [Figure 6] Figure 5 is a detailed view of the cross-section. [Figure 7] This is a detailed cross-sectional view in the front-to-back direction along line 7-7 in Figure 4, as seen in the direction of the arrow. [Figure 8] Figures 4-7 show perspective views of the acetabular shell components installed in the patient's hip joint. [Figure 9] Figures 1-3 are plan views of the acetabular bearing components located on the acetabular shell component installed in the hip joint of the patient in Figure 8. [Figure 10] This is a cross-sectional view in the front-to-back direction along line 10-10 in Figure 9, as seen in the direction of the arrow. [Figure 11]Figures 1-3 are plan views of the acetabular bearing components positioned on the acetabular shell component installed in the hip joint of the patient in Figure 10, and aligned by rotation. [Figure 12] This is a cross-sectional view in the front-to-back direction along line 12-12 in Figure 11, as seen in the direction of the arrow. [Figure 13] Figure 8 shows anterior-posterior cross-sectional views of the acetabular bearing components shown in Figures 4-7, fully installed in the acetabular shell component placed in the hip joint of the patient. [Figure 14] This is a detailed view of the cross-section shown in Figure 13. [Modes for carrying out the invention]

[0013] While the concepts of this disclosure are open to various modifications and alternative forms, specific exemplary embodiments are shown in the drawings and described in detail herein. However, it should be understood that the concepts of this disclosure are not intended to be limited to any particular form disclosed, but rather, the present invention is intended to encompass all modifications, equivalents, and alternatives that are included in the spirit and scope of the invention as defined by the appended "Claims."

[0014] Terms such as anterior, posterior, medial, lateral, superior, and inferior, which represent anatomical references, may be used throughout this specification in reference to the orthopedic implants and surgical instruments described herein, as well as to the innate anatomical morphology of patients. Such terms have well-understood meanings in both the study of anatomy and the field of orthopedic surgery. The use of such anatomical reference terms in the descriptions and claims is intended to be consistent with their well-understood meanings unless otherwise specified.

[0015] Referring now to Figures 1 to 3, an exemplary acetabular prosthesis includes an acetabular bearing 10. The bearing 10 is formed from a polymeric material such as Ultra-High-Molecular-Weight (UHMW) Polyethylene (PE), highly cross-linked PE, antioxidant-filled PE, or other polymers such as Polyether Ether Ketone (PEEK). The bearing 10 has an annular rim 12 and a convex outer surface 14 extending inwardly from the annular rim 12 to an apex 16. A concave inner surface 18 extends inwardly from the annular rim 12. In some embodiments, an angled chamfer 20 may separate the annular rim 12 from the concave inner surface 18. The inner surface 18 defines a cavity 22 sized to receive a prosthetic component, such as a femoral head component (not shown), which may be formed from a metallic material, a ceramic material, or other materials. In other embodiments, the cavity 22 may be sized to receive a movable bearing, a anchored femoral head, or other prosthetic components. The cavity 22 further defines a polar axis 24. The polar axis 24 may be an axis of rotation. That is, the acetabular bearing 10 may be rotationally symmetric about the axis 24.

[0016] The outer surface 14 of the bearing 10 includes a hemispherical surface 26 extending outwardly from the apex 16, and a tapered surface 28 extending inwardly from the annular rim 12. An annular flange 30 is located between the hemispherical surface 26 and the tapered surface 28, and extends radially outward from the outer surface 14. As further described below, in use, the tapered surface 28 enables a friction lock between the acetabular bearing 10 and an acetabular shell component, and the flange 30 provides the acetabular bearing 10 with mechanical pull-out resistance and spin-out resistance.

[0017] The acetabular bearing 10 further comprises a plurality of anti-rotation keys 32, each of which extends radially outwardly from the tapered surface 28. The anti-rotation keys 32 are evenly distributed around the periphery of the tapered surface 28. As best shown in Figure 2, each anti-rotation key 32 includes an outer surface 34, an inner side surface 36 and an outer side surface 38. The outer surface 34 of each anti-rotation key 32 smoothly merges with the tapered surface 28, and the inner side surface 36 of each anti-rotation key 32 forms a ledge protruding outward from the tapered surface 28. As will be further described below, the anti-rotation keys 32 cooperate with corresponding anti-rotation slots of an acetabular shell component to rotationally align the acetabular bearing 10 and the acetabular shell component. In addition, although the acetabular bearing 10 is illustrated as including twelve anti-rotation keys 32, it should be understood that in other embodiments, the acetabular bearing 10 may include a different number of anti-rotation keys 32.

[0018] As shown in Figure 3, the outer surface 14 of the acetabular bearing 10 further includes a curved introduction surface 40 extending outward from the hemispherical surface 26. A point of tangency 42 is located at the transition between the hemispherical surface 26 and the curved introduction surface 40. The point of tangency 42 is a point of tangency in a geometric sense. That is, for the curve defined by the outer surface 14 at the transition between the hemispherical surface 26 and the curved introduction surface 40, there exists a single tangent line passing through the point of tangency 42. Therefore, the transition between the hemispherical surface 26 and the curved introduction surface 40 is smooth and free of discontinuities.

[0019] A flat flange surface 44 extends outward from the curved introduction surface 40. A point of tangency 46 is located at the transition between the curved introduction surface 40 and the flat flange surface 44. Again, this means that the transition between the surfaces 40 and 44 is smooth and free of discontinuities. A trailing edge surface 50 extends outward from the flat flange surface 44. Similarly, a pair of points of tangency 48, 52 are located between the flange surface 44 and the trailing edge surface 50. As illustrated, the point of tangency 48 is located between the flange surface 44 and a curved corner of the trailing edge surface 50, and the point of tangency 52 is located between the curved corner and a flat portion of the trailing edge surface 50.

[0020] The curved relief surface 54 extends outward from the trailing edge surface 50. Exemplarily, the relief surface 54 curves inward from the outer surface to the innermost point 56, and then curves outward to the tapered surface 28. The tapered surface 28 extends outward from the curved relief surface 56 to the annular rim 12, as shown in Figures 1 and 2. The contact point 58 is located in the transition between the relief surface 54 and the tapered surface 28.

[0021] As shown in Figures 2 and 3, the imaginary line 60 extends along the tapered surface 28. The imaginary line 60 and the polar axis 24 define an angle 62 that is exemplary 5.1°. Thus, since the acetabular bearing 10 is rotationally symmetric about the polar axis 24, in an exemplary embodiment, the opposing tapered surfaces 28 on both sides of the acetabular bearing 10 (e.g., the anterior and posterior sides, the upper and lower sides, or any other pair of opposing sides) define a taper angle of 10.2° (i.e., twice the angle 62). As will be further described below, this taper angle is slightly larger than the corresponding taper angle of the acetabular shell component, which is 10° in an exemplary embodiment. Naturally, in other embodiments, a different angle 62 (and therefore a different taper angle) may be used.

[0022] As shown in Figure 3, the flange surface 44 extends outward from the imaginary line 60. That is, the imaginary line 60 is located between the flange surface 44 and the inner surface 18. In contrast, the relief surface 54 extends inward from the imaginary line 60. In other words, the relief surface 54 is located between the imaginary line 60 and the inner surface 18. As will be further explained below, during use, the flange surface 44, which extends radially outward further than the tapered surface 28, contacts the corresponding tapered surface of the acetabular shell component. When the acetabular bearing 10 is inserted, the flange 30 deforms. The relief surface 54 relieves stress on the flange 30 so that when fully inserted, the flange 30 can return to its original shape without plastic deformation.

[0023] As further shown in Figures 2 and 3, another imaginary line 64 extends along the flange surface 44. The imaginary line 64 and the polar axis 24 define an angle 66 which is exemplary 12°. The angle 66 defined by the imaginary line 64 and the polar axis 24 is greater than the angle 62 defined by the imaginary line 60 and the polar axis 24. In addition, although shown as 12°, it should be understood that in other embodiments, the angle 66 may have a different value. For example, in some embodiments, the angle 66 may be in the range of 10° to 14°. As another example, the angle 66 may be about 2 degrees greater than the taper angle of the acetabular bearing 10.

[0024] Another imaginary line 68 extends along the posterior edge surface 50 and intersects with imaginary line 64. Imaginary lines 64 and 68 define an angle 70 which is exemplary 90°. As will be further described below, the posterior edge surface 50 may increase the pull-out resistance of the acetabular bearing 10.

[0025] As shown in Figure 3, the imaginary line segment 72 extends from the point of contact 42 at the transition between the hemisphere 26 and the curved introduction surface 40 to the innermost point 56 of the relief surface 54. The line segment 72 represents the boundary of the flange 30, and therefore the flange 30 includes material located between the line segment 72 and the outer surface 14. The line segment 72 includes a midpoint 74, and the imaginary dividing line 76 intersecting the midpoint 74 extends in the longitudinal direction parallel to the annular rim 12. The dividing line 76 divides the cross-sectional area bounded by the line segment 72 and the outer wall 14 into an inner region 78 and an outer region 80. The inner region 78 is bounded by the line segment 72, the dividing line 76 and the outer wall 14, and is located inside the dividing line 76 (i.e., toward the vertex 16). Similarly, the outer region 80 is bounded by the line segment 72, the dividing line 76, and the outer wall 14, but is located outside the dividing line 76 (i.e., toward the annular rim 12). The outer region 80 is larger than the inner region 78. For example, in some embodiments, the outward-facing area 80 may correspond to about 51% of the cross-sectional area bounded by the line segment 72 and the outer wall 14. Since the outer region 80 is larger than the inner region 78, this means that the majority of the material of the flange 30 is located outside the dividing line 76.

[0026] Referring here to Figures 4-7, the exemplary acetabular prosthesis further includes an acetabular shell component 100. The acetabular prosthesis shell component 100 is molded to be implanted in the surgically prepared acetabulum of the patient's pelvis, and as will be further described below, the shell component 100 is configured to receive the acetabular bearing 10. The shell component 100 is formed from an implant-grade metallic material such as cobalt-chromium or titanium. The shell component 100 has an annular rim 102 and an outer wall 104 extending inward from the annular rim 102. The outer wall 104 includes an annular outer surface 106 extending from the annular rim 102 to a convex curved outer surface 108. In the exemplary embodiment, the convex curved outer surface 108 is hemispherical and molded to match the shape of the patient's surgically prepared acetabulum. The shell component 100 also includes a Porocoat® external coating 110 that allows bone to biologically adhere to the shell component 100 after implantation. The Porocoat® external coating 110 covers the outer surface 108 and conforms to its geometric shape. It should be understood that in other embodiments, the Porocoat® external coating 110 may be omitted.

[0027] The shell component 100 further includes an inner wall 112 extending inward from the annular rim 102 so as to define a cavity 114 within the shell component 100. The exemplary cavity 114 is sized to receive the acetabular bearing 10 described above. The concave inner wall 112 further defines a polar axis 116 extending through the cavity 114. Similar to the polar axis 24 of the acetabular bearing 10, the polar axis 116 may be a rotational axis. That is, the acetabular shell component 100 may be rotationally symmetric about the axis 116.

[0028] The inner wall 112 of the shell component 100 further includes an annular tapered surface 118 extending inward from the annular rim 102 and a hemispherical surface 120 extending further inward from the tapered surface 118. As shown in Figure 5, the opposing tapered surfaces 118 on both sides of the shell component 100 (e.g., the front and rear sides, the upper and lower sides, or any other pair of opposing sides) define a taper angle 122. Exemplarily, the taper angle 122 of the shell component 100 is 10°, but in other embodiments, the taper angle 122 may have a different amount.

[0029] An annular groove 124 is defined in the inner wall 112 between the tapered surface 118 and the hemispherical surface 120. The annular groove 124 is defined by an inner wall 126 extending from the hemispherical surface 120 to the inner wall 130 and an outer wall 128 extending from the tapered surface 118 to the inner wall 130. As shown in Figures 6 and 7, the outer wall 128 and the inner wall 130 define an angle 132 which is exemplary 70°. As will be further described below, in use, the annular groove 124 is configured to receive the annular flange 30 of the acetabular bearing 10 when the acetabular bearing 10 is fully installed within the acetabular shell component 100.

[0030] As shown in Figures 4 to 6, multiple anti-rotation slots 134 are defined in the tapered surface 118 of the inner wall 112. The anti-rotation slots 134 are evenly distributed around the tapered surface 118 and are molded to receive the corresponding anti-rotation keys 32 of the acetabular bearing 10. As shown, each anti-rotation slot 134 is defined by an inner wall 136 that extends from the tapered surface 118 to the inner wall 138. As shown in Figure 6, the inner wall 138 smoothly fuses with the tapered surface 118, and the inner wall 136 defines a ledge between the anti-rotation slot 134 and the tapered surface 118. In particular, as shown in Figure 7, an annular microgroove notch 140 is further defined in the tapered surface 118. Each of the anti-rotation slots 134 extends into the annular microgroove notch 140. As shown in Figures 4 and 5, in an exemplary embodiment, multiple slots 142 are defined through surfaces 108 and 120. During use, screws, pins, or other fasteners may be inserted through the slots 142 to secure the shell component 100 to the patient's bone.

[0031] Referring next to Figures 8 to 14, the acetabular prostheses shown in Figures 1 to 7 may be used during orthopedic surgery. Figure 8 shows the patient's pelvis 200. As shown, the pelvis 200 includes three parts: the ilium 202, ischium 204, and pubis 206, which define the natural acetabulum 208. To perform the orthopedic procedure, the surgeon first surgically prepares the patient's bone to receive the acetabular shell component 100. For example, the surgeon may use a surgical reamer to prepare the patient's acetabulum 208 to receive the acetabular shell component 100. In some embodiments, the surgeon may also remove any existing acetabular components or other prosthesis components from the patient's bone. Next, the surgeon inserts the acetabular shell component 100 into the patient's surgically prepared acetabulum 208, and then embeds the shell component 100 into the patient's bone 200 or attaches it in other ways. In some embodiments, one or more bone screws or other fasteners may be inserted through the slot 142 to attach the shell component 100 to the bone 200.

[0032] After fixing the acetabular shell component 100 to the bone 200, the surgeon then places the acetabular bearing 10 on the acetabular shell component 100, as shown in Figures 9 and 10. As shown in Figure 9, when the surgeon places the acetabular bearing 10 on the acetabular shell component 100, the anti-rotation keys 32 do not need to be rotatably aligned with the anti-rotation slots 134. As shown in Figure 10, when the anti-rotation keys 32 are not rotatably aligned with the anti-rotation slots 134, the inner wall 36 of each anti-rotation key 32 contacts the annular rim 102 of the shell component 100, leaving the acetabular bearing 10 partially inserted into the shell component 100. When the anti-rotation keys 32 are not rotatably aligned with the anti-rotation slots 134, the flange surface 44 of the annular flange 30 is spaced apart from the tapered surface 118 of the shell component 100.

[0033] As shown in Figures 11 and 12, after positioning the acetabular bearing 10 on the shell component 100, the surgeon rotates the bearing 10 until the anti-rotation keys 32 align with the anti-rotation slots 134. Once the anti-rotation keys 32 and the anti-rotation slots 134 are aligned, the acetabular bearing 10 falls further into the acetabular shell component 100 until the flange surface 44 of the annular flange contacts the tapered surface 118 of the shell component 100, as shown in Figure 12. In addition, as shown, once the anti-rotation keys 32 and the anti-rotation slots 134 are aligned, each anti-rotation key 32 also partially enters the corresponding anti-rotation slot 134. That is, when aligned, the inner wall 36 of each anti-rotation key 32 is located under the annular rim 102 within the corresponding anti-rotation slot 134. Therefore, the acetabular bearing 10 provides feedback to the surgeon when the anti-rotation key 32 is rotatably aligned with the anti-rotation slot 134 by falling further into the shell component 100 and contacting the tapered surface 118.

[0034] Once the anti-rotation key 32 and the anti-rotation slot 134 are aligned, the surgeon advances the acetabular bearing 10 into the shell component 100 by insertion or other means. As the acetabular bearing 10 is inserted into the shell component 100, the flange 30 is deformed by the force applied to the flange surface 44 by the tapered surface 118. The surgeon continues to advance the acetabular bearing 10 into the shell component 100 until the acetabular bearing is fully inserted, as shown in Figures 13-14. Once the acetabular bearing 10 is fully seated, the flange 30 returns to its original shape. The flange 30 does not experience plastic deformation, damage, or other changes in shape after being fully seated.

[0035] As shown in the detailed view of Figure 14, when the acetabular bearing 10 is fully installed within the shell component 100, the tapered surface 28 of the bearing 10 contacts the tapered surface 118 of the shell component 100, and the hemispherical surface 26 of the acetabular bearing 10 contacts the hemispherical surface 120 of the shell component 100. The bearing 10 is held within the shell component 100 by frictional locking between the tapered surfaces 28 and 118.

[0036] Furthermore, once the acetabular bearing 10 is fully seated, the annular flange 30 of the bearing 10 is received by the annular groove 124 of the shell component 100. When fully seated, the surfaces 40, 44, and 50 of the annular flange 30 do not need to be in contact with the walls 126, 128, and 130 that define the annular groove 124. The annular flange 30 and the annular groove 124 cooperate to hold the acetabular bearing 10 within the shell component 100, thereby improving the pull-out resistance and spin-out resistance of the bearing 10. For example, if the bearing 10 begins to slide outward from the acetabular bearing 100, the posterior edge surface 50 of the acetabular bearing 10 comes into contact with the outer wall 128 of the acetabular shell component 100, thereby holding the annular flange 30 and increasing the pull-out resistance of the bearing 10. Similarly, as shown in Figure 14, when the bearing 10 begins to rotate so that it slides inward relative to the shell component 100, the entry surface 40 and / or flange surface 44 of the acetabular bearing 10 come into contact with the inner wall 126 of the acetabular shell component 100, thereby holding the annular flange 30 and increasing the spin-out resistance of the bearing 10.

[0037] While the drawings and the above description have illustrated and illustrated the present disclosure in detail, such illustrations and descriptions are, by their nature, illustrative and not limiting, and merely illustrate exemplary embodiments. It is understood that all changes and modifications included in the spirit of the present disclosure should be protected.

[0038] Several advantages of this disclosure arise from the various characteristics of the devices and assemblies described herein. It should be noted that alternative embodiments of the devices and assemblies of this disclosure may not include all of the described features, but will still benefit from at least some of the advantages of such features. Those skilled in the art will readily be able to independently implement devices and assemblies that incorporate one or more features of the present invention and are included within the spirit and scope of this disclosure as defined in the "Claims."

[0039] [Implementation Method] (1) Acetabular prosthesis assembly, An acetabular shell component configured to be implanted in a patient's surgically prepared acetabulum, comprising an annular rim and a concave inner wall extending inward from the annular rim, wherein the concave inner wall has a tapered surface with a plurality of anti-rotation slots defined therein, A polymer acetabular bearing component configured to be received by the acetabular shell component, comprising: (i) an annular rim; (ii) a convex outer wall extending inward from the annular rim to its apex; (iii) an annular flange extending radially outward from the outer wall; and (iv) a plurality of anti-rotation keys extending radially outward from the outer wall. (i) When the plurality of anti-rotation keys are positioned in rotational alignment with the plurality of anti-rotation slots, the flange of the acetabular bearing component is positioned in contact with the tapered surface of the acetabular shell component; and (ii) When the plurality of anti-rotation keys are positioned without rotational alignment with the plurality of anti-rotation slots, the flange of the acetabular bearing component is spaced apart from the tapered surface of the acetabular shell component, an acetabular prosthesis assembly. (2) The acetabular prosthesis assembly according to Embodiment 1, wherein when the plurality of anti-rotation keys are positioned without rotational alignment with the plurality of anti-rotation slots, the inner surface of each of the plurality of anti-rotation keys is positioned in contact with the annular rim of the acetabular shell component. (3) The acetabular prosthesis assembly according to Embodiment 2, wherein when the plurality of anti-rotation keys are aligned by rotation with the plurality of anti-rotation slots, the inner surface of each of the plurality of anti-rotation keys is located within the corresponding anti-rotation slot among the plurality of anti-rotation slots. (4) The acetabular prosthesis assembly according to Embodiment 3, wherein when the plurality of anti-rotation keys are aligned by rotation with the plurality of anti-rotation slots, the inner surface of each of the plurality of anti-rotation keys is located a predetermined distance inward from the annular rim of the acetabular shell component. (5) The acetabular prosthesis assembly according to Embodiment 4, wherein the predetermined distance includes 0.5 mm.

[0040] (6) The acetabular prosthesis assembly according to Embodiment 1, wherein the plurality of anti-rotation keys are evenly spaced around the annular rim of the acetabular bearing component. (7) The acetabular prosthesis assembly according to Embodiment 1, wherein the plurality of anti-rotation keys are positioned in rotational alignment with the plurality of anti-rotation slots, and when the acetabular bearing component is fully installed within the acetabular shell component, each of the plurality of anti-rotation keys is located within a corresponding anti-rotation slot among the plurality of anti-rotation slots. (8) The acetabular prosthesis assembly according to Embodiment 7, wherein the plurality of anti-rotation keys are rotatably aligned with the plurality of anti-rotation slots and the acetabular bearing component is fully installed within the acetabular shell component, the flange is received in an annular groove defined in the concave inner wall of the acetabular shell component. (9) The acetabular prosthesis assembly according to Embodiment 1, wherein the outer wall of the acetabular bearing component includes a tapered surface extending inward from the annular rim. (10) The acetabular prosthesis assembly according to Embodiment 9, wherein the plurality of anti-rotation keys extend radially outward from the tapered surface.

[0041] (11) The acetabular prosthesis assembly according to Embodiment 9, wherein the outer wall of the acetabular bearing component includes a curved relief surface located between the tapered surface and the flange, the curved relief surface extending radially inward from the tapered surface and the flange. (12) The tapered surface of the acetabular shell component defines a taper angle, The acetabular prosthesis assembly according to Embodiment 1, wherein the flange of the acetabular bearing component includes a flange surface that defines a flange angle, and the flange angle is greater than or equal to the taper angle. (13) The acetabular prosthesis assembly according to Embodiment 12, wherein the taper angle is 10° and the flange angle is 10 to 14°. (14) The acetabular prosthesis assembly according to Embodiment 13, wherein the flange angle is 12°. (15) A method for implanting an acetabular prosthesis, The implantation of an acetabular shell component into a surgically prepared acetabulum of a patient, wherein the acetabular shell component comprises an annular rim and a concave inner wall extending inward from the annular rim, the concave inner wall having a tapered surface with a plurality of anti-rotation slots defined therein. Moving the acetabular bearing component so as to contact the embedded acetabular shell component, wherein the acetabular bearing component includes (i) an annular rim, (ii) a convex outer wall extending inward from the annular rim to its apex, (iii) an annular flange extending radially outward from the outer wall, and (iv) a plurality of anti-rotation keys extending radially outward from the outer wall. A method comprising rotating the acetabular bearing component relative to the embedded acetabular shell component from a first position in which the plurality of anti-rotation keys are not positioned in rotation with respect to the plurality of anti-rotation slots to a second position in which the plurality of anti-rotation keys are positioned in rotation with respect to the plurality of anti-rotation slots, wherein when in the first position, the flange of the acetabular bearing component is spaced apart from the tapered surface of the acetabular shell component, and when in the second position, the flange of the acetabular bearing component is in contact with the tapered surface of the acetabular shell component.

[0042] (16) The method of embodiment 15, further comprising fitting the acetabular bearing component into the embedded acetabular shell component when the acetabular bearing component is in the second position. (17) The method of embodiment 16, wherein inserting the acetabular bearing component includes deforming the flange of the acetabular bearing component. (18) The method of embodiment 17, further comprising receiving the flange of the acetabular bearing component into an annular groove defined in the concave inner wall of the acetabular shell component. (19) The method of embodiment 18, wherein receiving the flange into the annular groove includes elastically relaxing the flange to its original shape. (20) The method according to embodiment 18, wherein receiving the flange in the annular groove involves engaging the tapered surface of the acetabular bearing component with the tapered surface of the acetabular shell component.

Claims

1. Acetabular prosthesis assembly, An acetabular shell component configured to be implanted in a patient's surgically prepared acetabulum, comprising an annular rim and a concave inner wall extending inward from the annular rim, wherein the concave inner wall has a tapered surface with a plurality of anti-rotation slots defined therein, A polymer acetabular bearing component configured to be received by the acetabular shell component, comprising: (i) an annular rim; (ii) a convex outer wall extending inward from the annular rim to the apex of the polymer acetabular bearing component; (iii) an annular flange extending radially outward from the outer wall; and (iv) a plurality of anti-rotation keys extending radially outward from the outer wall. (i) When the plurality of anti-rotation keys are positioned in rotational alignment with the plurality of anti-rotation slots, the flange of the acetabular bearing component is positioned in contact with the tapered surface of the acetabular shell component; (ii) When the plurality of anti-rotation keys are positioned without rotational alignment with the plurality of anti-rotation slots, the flange of the acetabular bearing component is spaced apart from the tapered surface of the acetabular shell component. The outer wall of the acetabular bearing component includes a tapered surface extending inward from the annular rim of the acetabular bearing component. The outer wall of the acetabular bearing component includes a curved relief surface located between the tapered surface and the flange of the acetabular bearing component, the curved relief surface extending radially inward from the tapered surface of the acetabular bearing component, An acetabular prosthesis assembly wherein the outer wall of the acetabular bearing component includes a posterior edge surface located between the flange and the curved relief surface, and the lines extending along the flange surface of the flange and the lines extending along the posterior edge surface are perpendicular to each other.

2. The acetabular prosthesis assembly according to claim 1, wherein when the plurality of anti-rotation keys are positioned without rotational alignment with the plurality of anti-rotation slots, the inner surface of each of the plurality of anti-rotation keys is positioned in contact with the annular rim of the acetabular shell component.

3. The acetabular prosthesis assembly according to claim 2, wherein when the plurality of anti-rotation keys are aligned by rotation with the plurality of anti-rotation slots, the inner surface of each of the plurality of anti-rotation keys is located within the corresponding anti-rotation slot among the plurality of anti-rotation slots.

4. The acetabular prosthesis assembly according to claim 3, wherein when the plurality of anti-rotation keys are aligned by rotation with the plurality of anti-rotation slots, the inner surface of each of the plurality of anti-rotation keys is located a predetermined distance inward from the annular rim of the acetabular shell component.

5. The acetabular prosthesis assembly according to claim 4, wherein the predetermined distance includes 0.5 mm.

6. The acetabular prosthesis assembly according to claim 1, wherein the plurality of anti-rotation keys are evenly spaced around the annular rim of the acetabular bearing component.

7. The acetabular prosthesis assembly according to claim 1, wherein the plurality of anti-rotation keys are positioned in rotational alignment with the plurality of anti-rotation slots, and when the acetabular bearing component is fully installed within the acetabular shell component, each of the plurality of anti-rotation keys is located within a corresponding anti-rotation slot among the plurality of anti-rotation slots.

8. The acetabular prosthesis assembly according to claim 7, wherein the plurality of anti-rotation keys are positioned in rotational alignment with the plurality of anti-rotation slots, and when the acetabular bearing component is fully installed within the acetabular shell component, the flange is received in an annular groove defined in the concave inner wall of the acetabular shell component.

9. The acetabular prosthesis assembly according to claim 1, wherein the plurality of anti-rotation keys extend radially outward from the tapered surface of the acetabular bearing component.

10. The tapered surface of the acetabular shell component defines a taper angle. The acetabular prosthesis assembly according to claim 1, wherein the flange angle defined by the flange surface of the flange of the acetabular bearing component is greater than or equal to the taper angle.

11. The acetabular prosthesis assembly according to claim 10, wherein the taper angle is 10° and the flange angle is 10 to 14°.

12. The acetabular prosthesis assembly according to claim 11, wherein the flange angle is 12°.

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