Patent Application
20230119337
The present disclosure generally relates to glenoid implants for shoulder prosthesis.
A shoulder prosthesis includes a glenoid implant intended to replace the glenoid cavity of the scapula and/or a humeral implant intended to replace the humeral head. The glenoid implant generally includes an articular body intended to articulate with the humeral head, and a fixation means to stabilize the articular body with respect to the scapula.
Currently, clinical literature shows a high rate of radiolucency around glenoid cemented, non-cemented, and hybrid components in long-term use of those glenoid implants. One issue is the potential for rocking of the implant when shoulder joint is subjected to daily living activities. Currently, cemented implants provide good short- and mid-term fixation, but loosen over time. The current hybrid cemented-press fit implants show similar performance. Press fit implants historically show high loosening at mid- to long-term time points.
One of the challenges with press-fit glenoid implants is that it is difficult to reliably secure the implant to the bone, which is why hybrid cemented-press fit implants have increased in popularity. Adding a modular metal tray with screws is a solution that is used in many other joints, however in the shoulder there is often insufficient space for a modular tray. In addition, a modular connection between the metal tray and the bearing component may present a risk of unintended modular component separation, compared to a single piece implant.
Thus, improved glenoid implant design that offers enhanced and durable primary fixation to the bone is desired.
Provided is a glenoid implant system comprising a tray component that comprises a bone-facing surface and a bearing-facing surface on opposite side of the bone-facing surface; and
a bearing component that comprises an articulating surface that is generally concave and a back side on opposite side of the articulating surface that is generally convex, wherein the articulating surface is configured for engaging a convex humeral head and the back side is configured for engaging the bearing-facing surface of the tray component enabling the bearing component to slide about on the tray component while the convex humeral head articulates against the articulating surface.
In some embodiments, the glenoid implant system comprises a motion limiting feature that limits the range of motion of the bearing component sliding about the bearing-facing surface of the tray component.
In some embodiments, the motion limiting feature can comprise the bearing-facing surface being defined by more than one radii of curvature wherein the bearing-facing surface comprises: a central region that is a spherical surface having a curvature defined by the first radius of curvature; and a peripheral portion that is a spherical surface having a curvature defined by a second radius of curvature that is smaller than the first radius of curvature.
In some embodiments, the motion limiting feature can comprise a continuous ridge that extends along the bearing-facing surface's perimeter and is raised from the bearing-facing surface away from the bone-facing surface.
In some embodiments, the motion limiting feature can comprise two or more ridge segments that extend along the bearing-facing surface's perimeter and are raised from the bearing-facing surface away from the bone-facing surface. The motion limiting feature wherein the motion limiting feature comprises a boss provided on the back side of the articulating component and a pocket provided on the bearing-facing surface of the tray component, wherein the pocket has an opening that is larger than the boss.
In some embodiments, the motion limiting feature comprises a pocket provided on the back side of the articulating component and a boss provided on the bearing-facing surface of the tray component, wherein the pocket has an opening that is larger than the boss.
The various embodiments of the inventive hydrogel implant of the present disclosure will be described in more detail in conjunction with the following drawing figures. The structures in the drawing figures are illustrated schematically and are not necessarily intended to show actual dimensions or relative scale.
The glenoid implant system of claim 14, comprising a motion limiting feature that limits the range of motion of the bearing component sliding about the bearing-facing surface of the tray component.
This description of the exemplary embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description. The drawing figures are not necessarily to scale and certain features may be shown exaggerated in scale or in somewhat schematic form in the interest of clarity and conciseness. In the description, relative terms such as “horizontal,” “vertical,” “up,” “down,” “top” and “bottom” as well as derivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing figure under discussion. These relative terms are for convenience of description and normally are not intended to require a particular orientation. Terms including “inwardly” versus “outwardly,” “longitudinal” versus “lateral” and the like are to be interpreted relative to one another or relative to an axis of elongation, or an axis or center of rotation, as appropriate. Terms concerning attachments, coupling and the like, such as “connected” and “interconnected,” refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. When only a single machine is illustrated, the term “machine” shall also be taken to include any collection of machines that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein. The term “operatively connected” is such an attachment, coupling or connection that allows the pertinent structures to operate as intended by virtue of that relationship. In the claims, means-plus-function clauses, if used, are intended to cover the structures described, suggested, or rendered obvious by the written description or drawings for performing the recited function, including not only structural equivalents but also equivalent structures.
Provided herein are various improved glenoid bearing implants that have articulation surface that is configured to engage with an anatomical humeral head or a humeral component of a shoulder replacement implant system. Therefore, references to “a humeral head” as used herein should be construed to include both an anatomical humeral head as well as implant humeral head. Particularly, the improved glenoid bearing implant system disclosed herein comprises a tray component that is configured to be secured to a surface on a glenoid of a patient that is appropriately prepared and a bearing component that is not affixed to the tray component but rather configured to slidingly engage the tray component so that the bearing component is positioned between the tray component and the patient's humeral head when the glenoid implant system is implanted in the patient's shoulder. The bearing component in this position is relatively unconstrained while in engagement with the humeral head and the tray component and can slide about against the tray component through the patient's articulation of the shoulder joint. As will be described below, the implant components can be configured to limit the range of motion for the bearing component.
Referring to
The backside 133 of the bearing component 130 and the bearing-facing surface 123 of the tray component 120 have surfaces that are configured to engage each other in a sliding manner. The surface of the backside 133 has a generally convex contour and the bearing-facing surface 123 has a corresponding generally concave surface contour.
The articulating surface 132 of the bearing component 130 is generally concave. The articulating surface 132 is configured for engaging a convex humeral head and the back side 133 is generally convex and is configured for engaging the bearing-facing surface.
In some embodiments, the back side 133 of the bearing component 130 can be a spherical surface having a curvature defined by a first radius of curvature. In some embodiments, the bearing-facing surface 123 of the tray component can be a spherical surface having a curvature defined by the first radius of curvature.
In some embodiments, the glenoid implant system 100 can be provided with a motion limiting feature that limits the range of motion of the bearing component 130 while the bearing component 130 slides about on the tray component 120 while a convex humeral head articulates against the articulating surface after the glenoid implant system 100 has been implanted in a patient.
In some embodiments, the bearing-facing surface 123 has a complex contour defined by more than one radii of curvature. For example, the bearing-facing surface 123 in the central region can be defined by the first radius of curvature and the bearing-facing surface 123 along the periphery surrounding the central region can be defined by a second radius of curvature that is smaller than the first radius of curvature. This results in the central region that is flatter than the periphery and the surface of the periphery form a steeper curved surface surrounding the central region. The central region of the bearing-facing surface 123 is where the bearing component 130 is generally engaged and slides about relative to the tray component 120. Thus, as the bearing component 130 slides toward the periphery of the tray component 120 the bearing-facing surface 123 presents a steeper curvature surface and hinders or prevents the bearing component 130 from sliding further. Therefore, the smaller radius of curvature along the periphery of the bearing-facing surface 123 functions to limit the range of motion for the bearing component 130 to keep the bearing component 130 engaged to the tray component 120 during a patient's shoulder joint articulation after the glenoid implant system 100 is implanted in the patient's shoulder.
Referring to
In some embodiments, the ridge 125 can extend completely around the perimeter of the bearing-facing surface 123 without any breaks as shown in the example shown in
Referring to
The backside 233 of the bearing component 230 and the bearing-facing surface 223 of the tray component 220 have surfaces that are configured to engage each other in a sliding manner but with a predefined limited range of motion for the bearing component 230 so that the outer edges of the bearing component 230 does not travel beyond the perimeter of the tray component 220. The surface of the backside 233 has a generally convex contour and the bearing-facing surface 223 has a complementary generally concave surface contour but each is provided with a motion limiting feature that cooperate with one another.
The motion limiting feature on the backside 233 of the bearing component is a boss 235. The motion limiting feature on the bearing-facing surface 223 of the tray component 220 is a corresponding pocket 225. The pocket 225 has an opening that is larger than the boss 235 so that when the backside 233 of the bearing component 230 engages the bearing-facing surface 223 of the tray component, the boss 235 is completely received in the pocket 225 and allow the bearing component 230 to slide about against the bearing-facing surface 223.
Referring to
The backside 333 of the bearing component 330 and the bearing-facing surface 323 of the tray component 320 have surfaces that are configured to engage each other in a sliding manner but with a predefined limited range of motion for the bearing component 330 so that the outer edges of the bearing component 330 does not travel beyond the perimeter of the tray component 320. The surface of the backside 333 has a generally convex contour and the bearing-facing surface 323 has a complementary generally concave surface contour but each is provided with a motion limiting feature that cooperate with one another.
In the glenoid implant system 300, the motion limiting features on the bearing component 330 and the tray component 320 are opposite of those in the glenoid implant system 200. The motion limiting feature on the backside 333 of the bearing component is a pocket 335. The motion limiting feature on the bearing-facing surface 323 of the tray component 320 is a corresponding boss 325. The pocket 335 has an opening that is larger than the boss 325 so that when the backside 333 of the bearing component 330 engages the bearing-facing surface 323 of the tray component, the boss 325 is completely received in the pocket 335 and allow the bearing component 330 to slide about against the bearing-facing surface 323.
In the examples shown in
In some embodiments, the bearing components 130, 230, 330 can be formed of a high-modulus polymer. For example, the bearing component can be formed of high-modulus polyethylene (HMPE), ultra-high-molecular-weight polyethylene (UHMWPE), or any of the known polyethylene.
Referring to
In some embodiments, the bone-facing surface 122, 222, 322 further comprises one or more peripheral fixation features 150, 155, 250, 255, 350, 355. The peripheral fixation features extend from the bone-facing surface 122, 222, 322 in a direction that is away from the bearing-facing surface as shown in
In some embodiments, the one or more peripheral fixation features can be posts 150, 250, 350. In other embodiments, the one or more peripheral fixation features can be provided in other structural forms such as rings, keels, screws, center post, etc. In some embodiments, the bone-facing surface 122, 222, 322 can be configured with one or more posts as at least part of the one or more peripheral fixation features.
In some embodiments, the one or more peripheral fixation features is an annular ring 155, 255, 355. The annular ring 155, 255, 355 can be configured into two or more segments. For example, in the example shown in
In some embodiments, the one or more peripheral fixation features 150, 155, 250, 255, 350, 355 also can comprise a layer of a porous material so that at least some portion of the bone-facing surface 122, 222, 322 that comprises a layer P of a porous material can include the surfaces of the one or more peripheral fixation features 150, 155, 250, 255, 350, 355 that comprise a layer of porous material.
In some embodiments, the bearing component 130, 230, 330 can be formed of a high-modulus polymer. For example, the bearing component can be formed of high-modulus polyethylene (HMPE), ultra-high-molecular-weight polyethylene (UHMWPE), or any of the known polyethylene.
In some embodiments, the tray component 120, 220, 320 can be formed of a biocompatible metal alloys well known in the art. The bearing-facing surface 123, 223, 323 of the tray component can be a polished and hardened surface. The tray component 120, 220, 320 can be formed of a titanium alloy such as Ti-6Al-4V (also known as TC4 or Ti64). In some embodiments, the tray component 120, 220, 320 can be formed of a cemented PEEK.
Also within the scope of this disclosure is a surgical kit that includes one or more of the glenoid implant systems embodiments described herein.
Although the devices, kits, systems, and methods have been described in terms of exemplary embodiments, they are not limited thereto. Rather, the appended claims should be construed broadly, to include other variants and embodiments of the devices, kits, systems, and methods, which may be made by those skilled in the art without departing from the scope and range of equivalents of the devices, kits, systems, and methods.
This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 63/262,567, filed on Oct. 15, 2021, the entire contents of which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 63262567 | Oct 2021 | US |
