Modular stemless implants for arthroplasty implant systems

The modular stemless implant system addresses joint instability by engaging cortical and cancellous bone with a threaded cup and flange design, providing enhanced fixation and stability for joint reconstruction, suitable for various arthroplasty procedures.

JP7739617B2Active Publication Date: 2025-09-16ARTHREX INC
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Patent Information

Application Number
JP2024527637
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Priority Date
2021-11-11
Filing Date
2022-11-10
Publication Date
2025-09-16
Estimated Expiration
2042-11-10

AI Technical Summary

Technical Problem

Existing joint arthroplasty procedures face challenges in effectively restoring joint function due to bone erosion and loss, particularly in areas lacking a stable fixation mechanism for implants, leading to instability and pain.

Method used

A modular stemless implant system with a threaded cup and flange design that engages cortical and cancellous bone, providing a convertible platform for joint implants, utilizing materials like PEEK and featuring self-tapping threads and a flange for enhanced fixation, along with a modular design for anatomical and reverse shoulder arthroplasty.

Benefits of technology

The system offers improved fixation and stability, allowing for customizable joint reconstruction and reduced loosening, enhancing the longevity and functionality of joint replacements.

✦ Generated by Eureka AI based on patent content.

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Abstract

An arthroplasty implant system and method for restoring function to a joint is provided. The arthroplasty implant system may include a modular threaded cup (16) having a cylindrical body (26) and a flange (28) removably connectable to the cylindrical body. A thread (36) may be provided on the cylindrical body. The thread is configured to engage cortical and / or cancellous bone of the bone, and the flange is sized to engage the cortical rim of the bone.
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Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This disclosure claims priority to U.S. Provisional Patent Application No. 63 / 278,232, filed November 11, 2021, the entire contents of which are incorporated herein by reference. [Background technology]

[0002] The present disclosure relates to the field of joint arthroplasty, and more particularly to an arthroplasty implant system including a modular implant capable of establishing a stemless convertible platform for mating with a joint implant.

[0003] Many bones in the human musculoskeletal system contain articular surfaces that work together to facilitate different types and degrees of joint movement. Over time, articular surfaces can erode or experience bone loss due to repeated use or wear, thereby causing joint instability and pain.

[0004] Joint arthroplasty is an orthopedic surgical procedure performed to repair or replace joints that exhibit degenerative bone defects. Bone defects can occur along the articular surface of a bone. Some joint arthroplasty procedures utilize one or more implants to repair the articular surface. Summary of the Invention [Means for solving the problem]

[0005] FIELD OF THE DISCLOSURE The present disclosure relates to arthroplasty implant systems and methods designed to restore joint function. The arthroplasty implant system may include an implant assembly that includes a stemless convertible implant.

[0006] An exemplary humeral implant assembly for an arthroplasty implant system may include, among other things, an articular implant and a modular stemless implant adapted to establish a convertible platform for receiving the articular implant. The modular stemless implant includes threads configured to engage the cortical and / or cancellous bone of the bone and a flange sized to engage the cortical rim of the bone.

[0007] In a further embodiment, the joint implant is an anatomical joint implant that includes a convex articular surface.

[0008] In a further embodiment, the joint implant is a reverse joint implant that includes a concave articular surface.

[0009] In a further embodiment, the joint implant includes a spacer coupled to the stemless implant and a liner coupled to the spacer, the liner including a concave articular surface.

[0010] In a further embodiment, the spacer is connected to the stemless implant by a C-ring.

[0011] In a further embodiment, the stemless implant is made from a polyetheretherketone (PEEK) material.

[0012] In a further embodiment, the modular stemless implant includes a receiving cavity adapted to receive the joint implant, the receiving cavity extending inward from the rounded base edge of the modular stemless implant to the floor.

[0013] In a further embodiment, the threads are circumferentially disposed about the radially outer surface of the cylindrical body of the modular stemless implant.

[0014] In a further embodiment, the flange is removably connectable to the cylindrical body.

[0015] In a further embodiment, the outer diameter of the flange is greater than the outer diameter of the cylindrical body at the tip of the threads.

[0016] In a further embodiment, the cylindrical body includes a plurality of pockets adapted to promote bone ingrowth.

[0017] In a further embodiment, the flange includes a plurality of suture eyelets each configured to receive a thread-like material.

[0018] An exemplary arthroplasty implant system may include, among other things, a two-piece modular threaded cup having a cylindrical body and a flange removably connectable to the cylindrical body. Threads may be provided on the cylindrical body. The threads are configured to engage the cortical and / or cancellous bone of the bone, and the flange is configured to engage the cortical rim of the bone.

[0019] In a further embodiment, the flange is a separate component from the cylindrical body to establish a two-piece modular design of the threaded cup.

[0020] In a further embodiment, the threaded cup embodies an inlay design that establishes a convertible platform for receiving a joint implant.

[0021] In a further embodiment, a flange is provided on a first side of the cylindrical body and a rounded base is provided on a second side of the cylindrical body.

[0022] In a further embodiment, the receiving cavity extends inwardly from the edge of the cylindrical body to the floor of the rounded base, the floor establishing the inner surface of the rounded base.

[0023] In a further embodiment, the at least one engagement opening is formed through the rounded base.

[0024] In a further embodiment, the outer diameter of the flange is greater than the outer diameter of the cylindrical body at the tip of the threads.

[0025] In a further embodiment, the cylindrical body includes a plurality of pockets adapted to promote bone ingrowth.

[0026] In a further embodiment, the flange includes a plurality of suture eyelets each configured to receive a thread-like material.

[0027] In a further embodiment, the inserter system includes a drive shaft configured to engage a cylindrical body of the threaded cup and a cage assembly configured to engage a flange of the threaded cup.

[0028] In a further embodiment, the drive shaft includes an inner shaft having a threaded distal tip for engaging an engagement opening in the cylindrical body, and the cage assembly includes mounting legs having tapered teeth configured to engage tapered slots in the flange.

[0029] An exemplary surgical method may include, among other things, preparing the bone to receive the threaded cup, positioning the flange of the threaded cup against the cortical rim of the bone, and screwing the cylindrical body of the threaded cup through the flange and into the bone. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 1 shows a humeral implant assembly of an arthroplasty implant system. [Figure 2] FIG. 2 illustrates another exemplary humeral implant assembly of an arthroplasty implant system. [Figure 3] FIG. 3 is an exploded view of an exemplary threaded cup of a humeral implant assembly. [Figure 4] 4 is a cross-sectional perspective view of the threaded cup of FIG. 3. FIG. [Figure 5]FIG. 5 illustrates several flange options that may be provided on the threaded cup of FIG. [Figure 6] FIG. 6 illustrates the flange of the threaded cup of FIG. 3 engaging the cortical rim of bone. [Figure 7] FIG. 7 illustrates various details associated with the circumferential threads of the threaded cup of FIGS. [Figure 8] FIG. 8 schematically illustrates an exemplary surgical method for performing a shoulder arthroplasty procedure. [Figure 9] FIG. 9 illustrates a humeral implant assembly including a threaded cup. [Figure 10] FIG. 10 is an exploded view of the humeral implant assembly of FIG. [Figure 11] 11 is a cross-sectional view of the humeral implant assembly of FIG. 9. FIG. [Figure 12] 12A and 12B illustrate a spacer of another exemplary humeral implant assembly. [Figure 13] FIG. 13 illustrates a liner of the humeral implant assembly of FIG. [Figure 14] FIG. 14 illustrates another exemplary liner for the humeral implant assembly of FIG. [Figure 15] FIG. 15 illustrates an inserter system for implanting a threaded cup. [Figure 16] FIG. 16 is an exploded view of the inserter system of FIG. [Figure 17] FIG. 17 is a cross-sectional view of the inserter system of FIG. [Figure 18] FIG. 18 illustrates selected portions of the inserter system of FIG. [Figure 19] FIG. 19 illustrates additional selected portions of the inserter system of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0031] The present disclosure describes an arthroplasty implant system and method for restoring joint function. The arthroplasty implant system may include an implant capable of establishing a stemless convertible platform for mating with a joint implant.

[0032] In some implementations, the arthroplasty implant system of the present disclosure may include a modular threaded cup having a cylindrical body and a flange removably connectable to the cylindrical body. Threads may be provided on the cylindrical body. The threads are configured to engage the cortical and / or cancellous bone of the bone, and the flange is sized to engage the cortical rim of the bone. These and other features of the present disclosure are described in further detail below.

[0033] 1 illustrates an arthroplasty implant system 10 including a humeral implant assembly 12. The humeral implant assembly 12 may be implanted within the humerus 14 of the shoulder joint to aid in reconstructing the natural articular surface of the humerus 14 and / or restoring functionality (e.g., range or motion, stability, etc.) of the shoulder joint. Although not shown, the arthroplasty implant system 10 may additionally include a glenoid implant assembly configured to mate with the humeral implant assembly 12 to restore function of the shoulder joint. Furthermore, although the teachings of the present disclosure are described with particular reference to the shoulder joint, the present disclosure is not intended to be limited to any particular joint of the human musculoskeletal system and may be applicable to other joints, such as, for example, the hip joint.

[0034] The humeral implant assembly 12 may include a threaded cup 16 and an anatomical glenoid implant 18A (see FIG. 1 ) or a reverse glenoid implant 18B (see FIG. 2 ). The anatomical glenoid implant 18A may be utilized in combination with the threaded cup 16 to perform an anatomical total shoulder arthroplasty procedure, and the reverse glenoid implant 18B may be utilized in combination with the threaded cup 16 to perform a reverse shoulder arthroplasty procedure. In a reverse shoulder arthroplasty procedure, the reconstructed humerus 14 provides the socket portion, and the glenoid cavity (not shown) provides the ball portion of a ball-and-socket joint, which is the reverse of the natural anatomy. The anatomical glenoid implant 18A may include a convex glenoid surface 20A, and the reverse glenoid implant 18B may include a concave glenoid surface 20B. The articular surfaces 20A, 20B are configured to interface with the natural glenoid cavity or a glenoid implant assembly of the arthroplasty implant system 10.

[0035] In some implementations, the threaded cup 16, the anatomical joint implant 18A, and the reverse joint implant 18B may be provided together as part of a surgical kit, which may further include multiple sizes of each of the threaded cup 16, the anatomical joint implant 18A, and the reverse joint implant 18B.

[0036] In the illustrated embodiment, the humeral head of the humerus 14 has been resected, thus removing the natural glenoid components of the humerus 14 to prepare the humerus 14 for receiving the humeral implant assembly 12. After the humerus 14 has been properly prepared, the threaded cup 16 may be threaded into the metaphysis 22 of the humerus 14. In one embodiment, the threaded cup 16 is a stemless implant for the humeral implant assembly 12 and therefore lacks a stem that extends into the diaphysis 24 of the humerus 14. The threaded cup 16 may be configured to establish a convertible platform for receiving either an anatomical glenoid implant 18A or a reverse glenoid implant 18B. The anatomical glenoid implant 18A or the reverse glenoid implant 18B may be attached to the threaded cup 16 to assemble the humeral implant assembly 12.

[0037] The threaded cup 16 of the humeral implant assembly 12 is further illustrated in Figures 3, 4, and 5 (with continued reference to Figures 1 and 2). In one embodiment, the threaded cup 16 is constructed of a titanium material. In another embodiment, the threaded cup 16 may be made of a material having a modulus of elasticity relatively close to that of cortical bone, such as, for example, polyetheretherketone (PEEK). Alternatively, other materials for constructing the threaded cup 16 may be utilized within the scope of the present disclosure.

[0038] The threaded cup 16 may include a cylindrical body 26 and a flange 28. In this embodiment, the threaded cup 16 embodies a two-piece modular design, with the flange 28 being removably connectable to the cylindrical body 26.

[0039] The cylindrical body 26 may extend between a rim 25 located at the top or proximal side of the cylindrical body 26 and a rounded base 30 located at the bottom or distal side of the cylindrical body 26. Thus, the rim 25 may be located on the opposite side of the cylindrical body 26 from the rounded base 30.

[0040] Flange 28 may be removably connected to rim 25 of cylindrical body 26. For example, rim 25 of cylindrical body 26 may include a tapered outer circumferential surface 27, and flange 28 may include a tapered inner circumferential surface 29. Tapered inner circumferential surface 29 may be configured to engage tapered outer circumferential surface 27 via an interference fit to connect flange 28 to cylindrical body 26. In one embodiment, tapered outer circumferential surface 27 and tapered inner circumferential surface 29 taper in a proximal-to-distal direction.

[0041] The receiving cavity 32 of the threaded cup 16 may be configured to receive and secure either an anatomical joint implant 18A or a reverse joint implant 18B to the threaded cup 16. The receiving cavity 32 may be circumferentially surrounded by a flange 28 and a cylindrical body 26. The receiving cavity 32 may extend inwardly from the rim 25 to a floor 34 of a rounded base 30. The floor 34 may define the inner surface of the rounded base 30.

[0042] The receiving cavity 32 may provide an inlay design in which, after implantation, the majority of the threaded cup 16 (except for the flange 28) is located inside the humerus 14. In this way, the connection between the threaded cup 16 and the joint implants 18A, 18B is also inset rather than presenting an onlay design.

[0043] The threads 36 may be circumferentially disposed about a radially outer surface 38 of the cylindrical body 26. The threads 36 may be self-tapping threads configured to allow the threaded cup 16 to be screwed into the humerus 14. The threads 36 may be configured such that either a clockwise or counterclockwise rotation functions to advance the threaded cup 16 into the humerus 14.

[0044] In one embodiment, the outer diameter D1 of the flange 28 is larger than the outer diameter D2 of the cylindrical body 26 (here defined by the tip of the threads 36) (see, e.g., FIG. 4). The outer diameter D1 of the flange 28 may be sized to allow the flange 28 to engage with the cortical rim 40 of the humerus 14 (see, e.g., FIG. 6). Such engagement of the cortical rim 40 may provide additional fixation support and better load the proximal portion of the humerus 14.

[0045] Additionally, the outer diameter D2 may be sized such that when the threaded cup 16 is inserted therein, the threads 36 are positioned relatively close to the cortical bone 42 of the humerus 14 (see, e.g., FIG. 6 ). Securing the threaded cup 16 with the threads 36 as close as possible to the cortical bone 42 may provide improved initial and long-term fixation compared to “press-fit” implant designs. Thus, the threads 36 may engage the cortical bone 42, the cancellous bone 43, or both.

[0046] Cylindrical body 26 may further include an inner diameter D3. Inner diameter D3 may establish the cup size of threaded cup 16. Inner diameter D3 may be smaller than both outer diameter D1 and outer diameter D2.

[0047] The actual dimensions of the outer diameter D1 of the flange 28, the outer diameter D2 of the cylindrical body 26, and the inner diameter D3 of the cylindrical body 26 may vary depending on, among other factors, the size of the patient. The above-referenced surgical kit may include a threaded cup having multiple combinations of outer diameter sizes of the flange 28 and inner diameter sizes of the cylindrical body 26. Multiple exemplary sizes of flanges (identified as 28-1 through 28-N, where "N" is any number) that may optionally be utilized with the cylindrical body 26 of the threaded cup 16 are shown in FIG. 5.

[0048] Table 1 below shows exemplary sizes of threaded cup 16 that may be provided as part of a surgical kit. The listed sizes are intended to be exemplary only and therefore non-limiting. [Table 1]

[0049] The flange 28 of the threaded cup 16 may be either circular or oval, however, the actual shape of the flange 28 is not intended to limit the present disclosure.

[0050] Flange 28 may include a plurality of anti-rotation tabs 35. Anti-rotation tabs 35 may protrude from a distal-facing surface 37 of flange 28. Anti-rotation tabs 35 may be driven into bone (e.g., humerus 14) to prevent flange 28 from rotating within the bone.

[0051] A plurality of suture eyelets 44 may extend through the flange 28. The suture eyelets 44 may be configured to receive a thread-like material, such as a suture 46 (see FIG. 4). The suture 46 may then be utilized to assist in fastening tissue (e.g., subscapularis, supraspinatus, etc.) to the humerus 14 in the area around the flange 28.

[0052] One or more notches or interruptions 48 may be formed in the rim 25 of the cylindrical body 26 of the threaded cup 16. The interruptions 48 are sized to receive an interface feature of a wedge / spacer (not shown) that may be utilized in combination with the threaded cup 16 to reduce loosening between the threaded cup 16 and the joint implants 18A, 18B. The interface feature of the wedge / spacer may engage with the wall of the rim 25 that outlines the interruptions 48 to prevent rotation of the wedge / spacer relative to the threaded cup 16.

[0053] One or more engagement openings 50 may be formed through the rounded base 30 of the threaded cup 16. The engagement openings 50 may be configured to receive additional mating features of the wedge / spacer. The engagement openings 50 may be, for example, threaded circular openings.

[0054] The rounded base 30 may include one or more additional engagement openings 52 formed therethrough. The engagement openings 52 may be configured to receive mating features of an inserter device that may be utilized to implant the threaded cup 16 within the humerus 14. The engagement openings 52 may be oval or circular, for example.

[0055] The threaded cup 16 may additionally include a plurality of pockets 54. In some implementations, the pockets 54 may be formed in the radially outer surface 38 of the cylindrical body 26 just inward or distal to the rim 25. The pockets 54 may promote bone ingrowth after insertion. Alternatively, or additionally, a porous coating may be applied to selected portions of the cylindrical body 26 to promote bone ingrowth. In yet another embodiment, the surface finish of the threads 36 may be grit blasted to promote bone ingrowth. In one embodiment, the pockets 54 may be oval.

[0056] 7 illustrates additional details associated with the threads 36 of the threaded cup 16. The threads 36 may include design characteristics such as a thread pitch 60, a thread angle 62, a thread tip width 64, a thread root width 66, a thread depth 68, and a thread root radius 70. Table 2 below shows exemplary design characteristics of the threads 36. The disclosed design characteristics are for illustrative purposes only; thus, other thread-specific constructions are contemplated as being within the scope of the present disclosure. In this disclosure, the term "about" means that the expressed quantity or range need not be exact, but may be approximated and / or may be larger or smaller, reflecting acceptable tolerances, conversion factors, measurement errors, etc. [Table 2]

[0057] The thread pitch 60 may be variable pitch. In one embodiment, the variable pitch increases in a direction extending from the proximal side of the threaded cup 16 toward the distal side of the threaded cup 16. In another embodiment, the variable pitch increases in a direction extending from the distal side of the threaded cup toward the proximal side of the threaded cup 16.

[0058] The threads 36 may be single, double, or triple threads, and the thread starts may be varied to control the amount of rotation it takes to seat the threaded cup 16 in the bone.

[0059] 8, with continued reference to FIGS. 1-7, schematically illustrates a surgical method 75 for performing a shoulder arthroplasty procedure. The surgical method 75 may include implanting a threaded cup 16 during the shoulder arthroplasty procedure. However, other joints may be repaired or replaced using procedures similar to those described below. It should further be understood that the surgical method 75 may include a greater or fewer number of steps, and that the steps may be performed in a different order within the scope of the present disclosure.

[0060] The method may begin at block 77 by preparing the humerus 14 to receive the threaded cup 16. Preparing the humerus 14 may include, for example, resecting the humeral head of the humerus 14 and preparing a cavity within the resected humerus to receive the cylindrical body 26.

[0061] Next, at block 79, the flange 28 may be positioned on the humeral cut plate. Next, at block 81, the cylindrical body 26 of the threaded cup 16 may be threaded into the prepared humerus 14. The cylindrical body 26 may be threaded through the opening in the flange 28 and into the humerus 14 until the rim 25 sits just above the cortical rim 40.

[0062] Once implantation is complete, the threads 36 of the threaded cup 16 may engage the humerus 14 near the cortical bone 42, and the flange 28 may be loaded against the cortical rim 40. Thus, the threads 36 may engage the cortical bone 42, the cancellous bone 43, or both.

[0063] Finally, at block 83, the glenoid implants 18A, 18B may be connected to the implanted threaded cup 16. The threaded cup 16 thus establishes a convertible platform for mating with either an anatomical glenoid implant or a reverse glenoid implant.

[0064] 9, 10, and 11, the threaded cup 16 may be utilized as part of a humeral implant assembly 99 of an arthroplasty implant system. In addition to the threaded cup 16, the humeral implant assembly 99 may include a spacer 78 and a liner 80. Together, the spacer 78 and the liner 80 may establish a glenoid implant 82 of the humeral implant assembly 99.

[0065] In this embodiment, the joint implant 82 is a reverse-type joint implant. Thus, the liner 80 may include a concave articular surface 84. However, anatomical joint implants are also contemplated within the scope of the present disclosure (see, e.g., FIG. 1).

[0066] The threaded cup 16 may include one or more engagement openings 91 formed in the rounded base 30. The engagement openings 91 may receive anti-rotation pegs 93 on the spacer 78 (or on the liner 80 if no spacer 78 is used) to rotationally stabilize the spacer 78 relative to the threaded cup 16.

[0067] A C-clip 86 may be used to connect the spacer 78 to the threaded cup 16, and the liner 80 may be connected to the spacer 78 by a tapered connection or any other connection. The C-clip 86 may be received within a circumferential groove 88 formed in the receiving cavity 32 of the threaded cup 16, and the C-clip 86 may further be received within a circumferential groove 90 formed in the spacer 78.

[0068] In one embodiment, liner 80 includes a locking block 92. Locking block 92 may be received within a notch 94 formed in spacer 78. Locking block 92 is configured to prevent C-clip 86 from deforming inward, allowing spacer 78 to disengage from threaded cup 16.

[0069] In another embodiment, the locking block 92 is provided by the spacer 78 (see, e.g., FIGS. 12A and 12B). In this implementation, the locking block 92 may be translated between an open position (FIG. 12A), in which the C-clip 86 is free to deform, and a locked position (FIG. 12B), in which the C-clip 86 is prevented from deforming. The locking block 92 may move from the open position to the locked position in response to a force applied by the liner 80 as the liner moves into interlocking engagement with the spacer 78.

[0070] In other implementations, the spacer 78 may be secured to the threaded cup 16 via a tapered connection. In still other implementations, the spacer 78 may be eliminated from the humeral implant assembly 99, and the liner 80 may be secured directly to the threaded cup 16, for example, via either a tapered connection or a C-clip. Thus, the present disclosure is not intended to be limited to the exact implementations shown in FIGS. 9-12B.

[0071] In one embodiment, the liner 80 is a metal component (see FIG. 13). In another embodiment, the liner 80 may include both a metal portion 96 and a polymer portion 98 (see FIG. 14). The polymer portion 98 may form the concave articular surface 84 of the joint implant 82 and may be insert molded into the shell provided by the metal portion 96.

[0072] 1-14, Figures 15, 16, 17, 18, and 19 illustrate an inserter system 100 for implanting a threaded cup 16 into a humerus 14. The inserter system 100 may include a handle 102, a drive shaft 104, a cage assembly 106, and a shaft assembly 108. Each of these components and their respective functions are further described below.

[0073] The shaft assembly 108 may include an outer shaft 110 and an inner shaft 112. The inner shaft 112 may be received within a bore in the outer shaft 110 and may be secured in position relative to the outer shaft 110 by a pair of capture pins 114 (see FIG. 18).

[0074] The inner shaft 112 may include a threaded distal tip 116 that may be threaded into the engagement opening 50 of the threaded cup 16 to attach the inserter system 100 to the threaded cup 16. The proximal tip 120 of the inner shaft 112 may include a hex tip design or any other connection suitable for attaching a peripheral component (e.g., a knob) to the inner shaft 112 to more easily thread the inner shaft 112 into the threaded cup 16.

[0075] The outer shaft 110 may include external threads 118 for securing the shaft assembly 108 to the cage assembly 106. The external threads 118 may be received within a central threaded opening 122 of the cage assembly 106 (see FIG. 19 ). The external threads 118 and the central threaded opening 122 cooperate to retain the threaded cup 16 recessed within the cage assembly 106 prior to insertion of the threaded cup 16 into the bone.

[0076] The cage assembly 106 may include a proximal portion 124 that receives a portion of the shaft assembly 108 and a distal portion 126 designed to mate with the flange 28 of the threaded cup 16. For example, the distal portion 126 may include a plurality of attachment legs 128, each including tapered teeth 130 sized to engage with a tapered slot 132 that may be formed through the flange 28. The tapered slot 132 is an additional opening separate from the suture eyelet 44. A suture (not shown) received within the suture eyelet 44 may be routed through the flange 28 and then through the slot 134 formed in the distal portion 126 and then wrapped around one or more suture wrap blocks 136, which may be attached to the proximal portion 124 of the cage assembly 106.

[0077] The handle 102 may include an outer grip 138 and an inner tube 140 including a proximal impaction surface 142 and a distal connector 144. The distal connector 144 may be connected to the proximal portion 124 of the cage assembly 106, such as via a spring seal 146 (see FIG. 17 ). The proximal impaction surface 142 may be exposed on the outside of the outer grip 138 and may be used to impact the flange 28 against the humerus 14. For example, the proximal impaction surface 142 may be impacted by a surgical mallet to drive the detent tabs 35 of the flange 28 into the humerus 14, thereby securing the flange 28 in place against the cortical rim 40.

[0078] The drive shaft 104 may be inserted through an inner tube 140 of the handle 102 for connection to the inner shaft 112 of the shaft assembly 108. The drive shaft 104 may include a cannula 148 for accommodating a portion of the inner shaft 112. The drive shaft 104 may be connected to the inner shaft 112 using, for example, another spring seal 150 (see FIG. 17 ).

[0079] After unscrewing the outer shaft 110 of the shaft assembly 108 from the cage assembly 106, the drive shaft 104 may be rotated to drive the threaded cup 16 into the humerus 14. The threaded cup 16 is threaded through an opening in the flange 28, as the flange 28 is held against the cortical rim 40 by the distal portion 126 of the cage assembly 106. The various subcomponents of the inserter system 100 may then be removed from the threaded cup 16 and flange 28 to complete the procedure.

[0080] An exemplary arthroplasty implant system of the present disclosure employs a modular stemless implant that can establish a stemless convertible platform for mating with a joint implant. The stemless implant may be configured as a threaded cup incorporating a modular flange (e.g., a circumferential ring / trunnion) adapted to rest on the cortical rim of the resected bone to provide additional fixation support and better load the bone during implantation. The stemless implant may further provide a mating design that allows for an inlay-reverse prosthesis configuration.

[0081] Although different non-limiting embodiments are illustrated as having particular components or steps, embodiments of the present disclosure are not limited to those particular combinations. Some of the components or features from any of the non-limiting embodiments can be used in combination with features or components from any of the other non-limiting embodiments.

[0082] It will be understood that like reference numerals identify corresponding or similar elements throughout the several views. It will further be understood that, while particular component arrangements are disclosed and illustrated in these exemplary embodiments, other arrangements can also benefit from the teachings of the present disclosure.

[0083] The foregoing description should be construed as illustrative and not in any limiting sense. Those skilled in the art will understand that certain modifications may fall within the scope of the present disclosure. For these reasons, the following claims should be studied to determine the true scope and content of the present disclosure. [Explanation of symbols]

[0084] 10 Arthroplasty Implant Systems 12 Humeral Implant Assembly 14 Humerus 16 Threaded Cup 18A Anatomical Joint Implants 18B Reverse-type joint implant 20A Articular Surface 20B Articular surface 22 Metaphysis 24 Diaphysis 25 rims 26 Main Unit 27 Outer surface 28 flange 29 Inner surface 30 base 32 Receptive Cavity 34 Floor 35 Anti-rotation tab 36 threads 37 sides 38 Radial outer surface 40 Cortical Rim 42 Cortical bone 43 Cancellous bone 44 Suture Eyelet 46 Sutures 48 Interruption 50 engagement opening 52 engagement opening 54 pockets 60 thread pitch 62 Thread angle 64 Screw tip width 66 Width of the screw base 68 thread depth 70 Thread root radius 75 Surgical methods 78 Spacer 80 Liner 82 Joint Implants 84 Articular Surface 86 C-clip 88 Circumferential groove 90 Circumferential groove 91 Engagement opening 92 Rock Block 93 Anti-rotation peg 94 Notch 96 Metal parts 98 Polymer part 99 Humeral Implant Assembly 100 Inserter System 102 Handle 104 Drive shaft 106 Cage Assembly 108 Shaft assembly 110 outer shaft 112 Inner Shaft 114 Capture Pin 116 Distal Tip 118 External Thread 120 Proximal Tip 122 central threaded opening 124 proximal part 126 Distal part 130 teeth 132 slots 134 slots 136 Suture Wrap Block 138 Outer Grip 140 inner tube 142 Proximal impact surface 144 Distal Connector 146 Spring seal 148 Cannula 150 Spring Seal D1 Outer diameter D2 outer diameter D3 inner diameter

Claims

1. 1. A humeral implant assembly for an arthroplasty implant system, comprising: joint implants and a modular stemless implant adapted to establish a convertible platform for receiving said joint implant; the modular stemless implant including threads configured to engage bone and a flange sized to engage a cortical rim of the bone; An assembly wherein the threads are circumferentially disposed around a radially outer surface of a cylindrical body of the modular stemless implant, and the flange is removably connectable to the cylindrical body.

2. 2. The assembly of claim 1, wherein the joint implant comprises a spacer coupled to the stemless implant and a liner coupled to the spacer, the liner further comprising a concave articular surface, and the spacer coupled to the stemless implant by a C-clip.

3. 3. The assembly of claim 1 or claim 2, wherein the modular stemless implant is made of polyetheretherketone (PEEK) material.

4. The assembly of claim 1, wherein the modular stemless implant includes a receiving cavity adapted to receive the joint implant, and further wherein the receiving cavity extends inward from a rounded base edge of the modular stemless implant to a floor.

5. 2. The assembly of claim 1, wherein an outer diameter of the flange is greater than an outer diameter of the cylindrical body at the tip of the threads, and the cylindrical body includes a plurality of pockets adapted to promote bone ingrowth.

6. The assembly of claim 1 , wherein the flange includes a plurality of suture eyelets each configured to receive a thread-like material.

7. a two-piece modular threaded cup including a cylindrical body, threads circumferentially disposed about a radially outer surface of said cylindrical body, and a flange removably connectable to said cylindrical body; The arthroplasty implant system, wherein the threads are configured to engage bone and the flange is sized to engage a cortical rim of the bone.

8. The arthroplasty implant system of claim 7 , wherein the flange is a separate component from the cylindrical body to establish the two-piece modular design of the threaded cup.

9. 9. The arthroplasty implant system of claim 7 or claim 8, wherein the threaded cup embodies an inlay design that establishes a convertible platform for receiving a joint implant.

10. 9. The arthroplasty implant system of claim 7 or claim 8, wherein the flange is provided on a first side of the cylindrical body and a rounded base is provided on a second side of the cylindrical body.

11. 11. The arthroplasty implant system of claim 10, wherein a receiving cavity extends inward from an edge of the cylindrical body to a floor of the rounded base, the floor further establishing an inner surface of the rounded base and including at least one engagement opening formed through the rounded base.

12. The arthroplasty implant system of claim 7 , wherein the flange has an outer diameter greater than the cylindrical body outer diameter at the tip of the threads.

13. 8. The arthroplasty implant system of claim 7, comprising an inserter system including a drive shaft configured to engage the cylindrical body and a cage assembly configured to engage the flange, the drive shaft including an inner shaft having a threaded distal tip for engaging an engagement opening in the cylindrical body, and the cage assembly including mounting legs having tapered teeth configured to engage tapered slots in the flange.

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