Offset adapter, trial implant system, and implant system that enable selection of eccentricity

Abstract

The present disclosure relates to an offset adapter, a trial implant system, a shoulder implant system, and a method for total shoulder replacement, in which the eccentricity of the humeral head relative to the humeral anchor and the resected proximal portion of the humerus is selectable by the surgeon. The humeral head implant system includes a humeral head, an adapter, and a humeral anchor. The offset adapter is operable to connect the humeral head to the humeral anchor. The offset adapter includes a first tapered cylindrical portion having a first axis and a second tapered cylindrical portion having a second axis, the first axis being eccentrically disposed relative to the second axis of the adapter. The trial humeral head system includes a trial humeral head, a pin guide, and a trial adapter. Allows for selectable eccentricity

Description

Related Applications

[0001] This application claims the benefit of priority of U.S. Provisional Patent Application No. 63 / 030,379, filed May 27, 2020, entitled "Offset Adapter Enabling Selectable Eccentricity, Trial Implant System, and Implant System", the disclosure of which is hereby incorporated by reference in its entirety.

Technical Field

[0002] The present disclosure generally relates to orthopedic surgery, implants, and methods for replacing joints, such as in the repair of the shoulder joint. More specifically, but not exclusively, the present disclosure relates to orthopedic surgery, humeral offset adapters, trial implant systems, and methods for total shoulder replacement in which the eccentricity of the humeral head relative to the humeral stem / anchor and the resected proximal portion of the humerus is selectable by a surgeon.

Background Art

[0003] In a typical anatomical total shoulder replacement, the damaged humeral head is replaced with a spherical metal head, and the damaged glenoid fossa is replaced with a smooth plastic bearing surface. In a partial shoulder replacement, only the damaged humeral head needs to be replaced.

[0004] Conventional humeral implants include a humeral head having an articular surface and a humeral anchor attachable to the resected humerus. The humeral anchor includes a post or stem receivable in the cavity of the resected humerus and the intramedullary canal of the humerus. The post or stem of the humeral anchor is centrally located. A plurality of humeral heads having cavities with different eccentricities relative to the central axis are necessary to enable a surgeon to select the desired humeral head offset for a particular patient.

Summary of the Invention

[0005] In one embodiment, for example, through the provision of a humeral head implant system having a humeral head, an offset adapter, and a humeral anchor, the drawbacks of the prior art are eliminated and further advantages are provided. The humeral head includes a first portion and a second portion. The first portion has an articular surface, and the first portion and the second portion define a central axis extending from the first portion to the second portion. The second portion has a surface with a tapered cavity therein, and the cavity has a recess therein. The cavity defines an axis that is offset and eccentric with respect to the central axis of the humeral head. The offset adapter includes a first tapered cylindrical portion having a first axis and a second tapered cylindrical portion having a second axis, and the first axis is arranged eccentrically with respect to the second axis of the offset adapter. The distal end of the first tapered cylindrical portion of the offset adapter includes a protrusion offset from the first axis of the first tapered cylindrical portion of the offset adapter and from the second axis of the second tapered cylindrical portion. The humeral anchor has a tapered cavity defining a central axis. The first tapered cylindrical portion of the offset adapter is receivable in the tapered cavity of the humeral head and has a protrusion receivable in the recess of the tapered cavity of the humeral head, and the second portion of the offset adapter is receivable in the cavity of the humeral anchor.

[0006] In another embodiment, an offset adapter for operably connecting a humeral head to a humeral anchor has, for example, a first tapered cylindrical portion having a first axis and a second tapered cylindrical portion having a second axis, and the first axis is arranged eccentrically with respect to the second axis of the offset adapter. The offset adapter also has a distal end of the first tapered cylindrical portion. The distal end includes a protrusion having a third axis offset from the first axis of the first tapered cylindrical portion of the offset adapter and from the second axis of the second tapered cylindrical portion.

[0007] In another embodiment, the trial humeral head system includes, for example, a trial humeral head, a pin guide, and a trial offset adapter. The trial humeral head has an outer hemispherical surface, an inner surface extending between the peripheries of the outer hemispherical surface, and an opening extending from the outer hemispherical surface to the inner surface. The outer hemispherical surface defines a central axis extending from the outer hemispherical surface to the inner surface through the opening. The inner surface includes an eccentric cavity extending around the opening. The pin guide includes an elongated member having a first end, a second end, and a passage extending through from the first end to the second end. The outwardly extending member is fixed to the first end of the elongated member. The outwardly extending member is releasably fixed to the eccentric cavity of the trial humeral head with the elongated member extending through the opening of the trial humeral head and the passage of the pin guide being concentric with the central axis of the trial humeral head. The trial offset adapter includes a tapered cylindrical portion, an outwardly extending member fixed to the tapered cylindrical portion, and a passage extending from the first tapered cylindrical portion to the outwardly extending member. The outwardly extending member can be releasably and adjustably fixed to the eccentric cavity of the trial humeral head.

[0008] In another embodiment, the surgical method includes, for example, assembling the humeral trial head and the pin guide; positioning the humeral trial head and the pin guide relative to the resected proximal humerus; inserting a pin through the pin guide into the resected humerus; removing the trial humeral head and the pin guide from the resected humerus and the inserted pin; preparing a cavity in the resected humerus using the pin; removing the pin from the resected humerus; removing the pin guide from the trial humeral head; fixing an offset adapter to the trial humeral head; selecting the degree of eccentricity of the trial offset adapter relative to the trial humeral head to adjust the position of the trial humeral head relative to the resected humerus; placing the assembled trial offset adapter and the trial humeral head on the resected humerus with the tapered cylindrical portion of the trial offset adapter disposed in the cavity of the humeral anchor disposed in the resected proximal humerus to confirm the position relative to the resected humerus; and selecting the humeral head and the offset adapter based on the assembled trial humeral head and the trial adapter.

[0009] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the detailed description of the invention, serve to explain the principles of the invention. The drawings are for the purpose of illustrating preferred embodiments only and are not to be construed as limiting the invention. It is emphasized that the various features are not drawn to scale in accordance with standard practice in the art. In fact, the dimensions of the various features may be arbitrarily increased or decreased for clarity of discussion. The foregoing and other objects, features, and advantages of the invention will be apparent from the following detailed description taken in conjunction with the accompanying drawings.

Brief Description of the Drawings

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DETAILED DESCRIPTION OF THE INVENTION

[0047] Generally, disclosed herein is, for example, an offset adapter, implant system, trial implant system, and method for orthopedic surgery for replacing a joint joint, such as when repairing a patient's shoulder joint. The offset adapter, implant system, trial implant system, and method enable a surgeon to select the eccentricity of the humeral head relative to the humeral anchor based on the patient's anatomy. As will be understood from this specification, the techniques of the present disclosure enable a surgeon to select a particular offset adapter from a plurality of different offset adapters that create different eccentricities for use with a humeral head implant system based on the particular anatomical structure of the patient when assembling with the humeral head. The techniques of the present disclosure typically require a number of different lines of humeral heads and trial humeral heads having different eccentricities, resulting in an excessive inventory and increasing the complexity of the procedure for repairing the patient's shoulder compared to conventional systems that require a reduced number of humeral heads and humeral trial heads.

[0048] In this detailed description and the following claims, the terms proximal, distal, front, rear, medial, lateral, upper, and lower are defined by their standard usage to indicate specific parts of a bone or implant according to the relative position or directionality terms of a natural bone. For example, "proximal" means the part of the device or implant closest to the torso, and "distal" indicates the part of the device or implant farthest from the torso. As directional terms, "front" is the direction towards the front side of the body, "rear" is the direction towards the rear side of the body, "medial" is the direction towards the midline of the body, "lateral" is the direction towards the side of the body or away from the midline, "upper" is the direction towards above another object or structure, and "lower" is the direction towards below.

[0049] As used herein, the word "exemplary" or "exemplification" means "serving as an example, instance, or illustration". Any implementation described as "exemplary" or "exemplification" in this specification is not necessarily construed as being more preferred or advantageous than other implementations. Further, in this specification, "upper", "lower", "left", "rear", "right", "front", "vertical", "horizontal", and their derivatives are related to the present invention as oriented in FIG. 1 of each embodiment.

[0050] Similarly, position or orientation may be used herein with reference to anatomical structures or surfaces. For example, since the present implants, devices, systems, and methods are described herein with reference to use with the bones of the shoulder, the shoulder and the bones of the upper arm may be used to describe the surface, position, orientation, or alignment of the implants, devices, systems, and methods. Further, the implants, devices, systems, and methods disclosed herein, as well as aspects, components, features, etc. thereof, are described with respect to one side of the body for purposes of brevity. However, since the human body is relatively symmetric or mirror-image about a line of symmetry (midline), the implants, devices, systems, and methods described and / or illustrated herein, as well as aspects, components, features, etc. thereof, are contemplated herein to be capable of being modified, varied, altered, reconfigured, or otherwise changed for use or association with another side of the body for the same or similar purposes without departing from the spirit and scope of the invention. For example, the implants, devices, systems, and methods, as well as aspects, components, features, etc. thereof, described herein with respect to the right shoulder may be mirrored such that they function similarly on the left shoulder, and vice versa. Further, while the implants, devices, systems, and methods disclosed herein, as well as aspects, components, features, etc. thereof, are described with respect to the shoulder for purposes of brevity, it is to be understood that the implants, devices, systems, and methods may be used with other bones of the body having a similar structure, such as the lower extremities, and more particularly, the bones of the ankle, foot, and leg.

[0051] Like reference numerals are used throughout several figures to indicate like or similar components, and in particular, referring to FIGS. 1-3, there are illustrated exemplary embodiments of a biocompatible humeral head implant system 10 for use in a total shoulder replacement system according to embodiments of the present disclosure. FIGS. 15-18 are exemplary embodiments of a trial humeral head and pin guide for use in selecting a trial humeral head and placing pins according to embodiments of the present disclosure. FIGS. 15, 27, and 28 show an exemplary embodiment of a trial humeral head and trial offset adapter for use in determining the eccentricity and orientation of a selected trial humeral head and offset adapter according to embodiments of the present disclosure. As will be understood from the following description, the techniques of the present disclosure may enable a surgeon to implant a humeral head with a selection of the eccentricity of the humeral head that matches the resected humerus with respect to the humeral anchor component. The techniques of the present disclosure may enable a surgeon to try with a single component that aids in selecting a particular eccentricity. The definitive implant may then be constructed to match the previously determined eccentricity. For example, a single humeral head and a plurality of offset adapters having, for example, dual tapers, enable various selections of eccentricities achievable when assembled into a humeral head implant system. Such techniques enable a surgeon to more quickly reconstruct the shoulder by faithfully reproducing the natural biomechanics of a normal shoulder compared to conventional total shoulder arthroplasty.

[0052] Referring again to FIG. 1, in this exemplary embodiment, the humeral head implant system 10 is operably attached to the resected proximal portion of the patient's humerus 12. As shown in FIGS. 2 and 3, the humeral head implant system 10 may include a humeral head 100, an offset adapter 200, and a humeral anchor 300.

[0053] As will be described in more detail below, in this illustrated embodiment, the humeral head 100 may have an offset cavity 130 (FIG. 3), the offset adapter 200 may have a first portion 210 and an offset second portion 220, and the humeral anchor 300 may have a centrally disposed cavity 370 (FIG. 2). The combination of the configurations of the humeral head 100, the offset adapter 200, and the humeral anchor 300 is operable to assist in eccentrically positioning the humeral head 100 relative to the resected proximal portion 12 (FIG. 1) of the patient's humerus. When the humeral anchor 300 is installed in the resected proximal humerus 12 (FIG. 1) of the patient, the surgeon can use a single configuration of the humeral head disposed over a range of positions, with the humeral head 100 and an offset adapter 200 selected from a plurality of offset adapters having different offsets as described below, to optimize the position of the peripheral edge 101 (FIG. 1) of the humeral head 100 relative to the resected proximal portion of the patient's humerus 12 (FIG. 1) and balance the surrounding soft tissue.

[0054] As will be described in more detail below, a plurality of different offset adapters as shown in FIGS. 12 and 13 may be provided, and during the trial procedure described in more detail below, the surgeon can determine and select one of a plurality of humeral heads and a plurality of offset adapters such that the eccentricity of the humeral head relative to the humeral anchor and the resected proximal humerus portion can be optimally positioned relative to the resected proximal portion of the patient's humerus. As can be understood from this specification, the number of humeral heads of different sizes and configurations and the number of offset adapters of different configurations can be reduced to favorably position the humeral head for a plurality of different patients, as compared to the number of conventional humeral heads having a specific eccentricity required to be used with a monoblock offset taper.

[0055] Furthermore, as shown in FIGS. 4 and 5, the humeral head 100 (FIG. 4) and the offset adapter 200 (FIG. 5) may be fixedly coupled to each other. For example, the offset adapter 200 (FIG. 5) may include a protrusion 250 (FIG. 5) that can be received in a recess 150 (FIG. 4) of the humeral head 100 (FIG. 4) to assist in fixing the offset adapter 200 (FIG. 5) from rotating relative to the humeral head 100 (FIG. 4). As described below, the assembled humeral head and offset adapter 200 may be aligned at a rotational position designed for the humeral anchor 300 (FIG. 2) and then fixed to the humeral anchor 300.

[0056] Referring to FIGS. 6-8, the offset adapter 200 may include a first portion 210 and an offset second portion 220 disposed on the opposite side of the first portion 210. The first portion 210 may include an upper distal end 212 and a lower proximal end 214. The upper distal end 212 may include an upper surface 215. The second portion 220 may include a lower distal end 222 and an upper proximal end 224. The lower distal end 222 may include a lower surface 225. The proximal end 214 of the offset adapter 200 may be operably joined to the proximal end 224 of the offset adapter 200 along an oval intermediate portion 230 that defines a first stop 232 and an opposite stop 234.

[0057] As shown in FIG. 7, the protrusion 250 extends away from the distal surface 215. The protrusion 250 may have a distal end 252 (FIG. 6) and a proximal end 254 (FIG. 6) attached to the upper surface 215 of the upper distal end 212 of the first portion 210 of the offset adapter 200.

[0058] Referring again to FIG. 5, the first portion 210 may define a first central axis A1, and the second portion 220 may define a second central axis A2. The first central axis A1 may be offset with respect to the second central axis A2 or may be eccentrically arranged. The protrusion 250 extending away from the distal surface 215 defines a central axis A3. The central axis A3 may be offset from the first central axis A1 of the first portion 210 of the offset adapter 200 or may be eccentrically arranged, and may be offset from the second central axis A2 of the second portion 220 of the offset adapter 200 or may be eccentrically arranged.

[0059] In some embodiments, the first portion 210 may be a tapered cylindrical portion or may have a frustoconical structure, and the second portion 220 of the offset adapter 200 may be a tapered cylindrical portion or may have a frustoconical structure. The configuration, size, and shape of the first portion 210 of the offset adapter 200 and the second portion 220 of the offset adapter 200 may be the same. In other embodiments, the first portion 210 and the second portion 220 of the offset adapter 200 may be configured differently. Also, the offset adapter 200 may include a through hole or a threaded opening 260 extending through the offset adapter 200 from the first portion 210 to the second portion 220.

[0060] Referring again to FIGS. 2 and 3, the proximal humeral head 100 may include a first portion 110 and a second portion 120. The first portion 110 of the proximal humeral head 100 may have an articular surface 112. The second portion 120 of the proximal humeral head 100 may be a connecting portion having a second or bottom surface 122 (FIG. 3) disposed on the side opposite to the articular surface 112.

[0061] The articular surface 112 may be a convex surface such as the surface of a hemisphere of a spherical cap, or alternatively, an aspherical surface. The first portion 110 and the second portion 120 of the humeral head 100 may define a central axis A4 extending from the first portion 110 to the second portion 120 of the humeral head 100. The second or connecting portion 120 may include a concave opening 130 (FIG. 3), such as a tapered cavity extending towards the articular surface 112 and towards the second or bottom surface 122.

[0062] As shown in FIG. 4, the second or connecting portion 120 may include a concave region 140 forming a concave lip 142 extending in the circumferential direction surrounding, for example, the concave cavity 130. The recessed region 140 may be sized and shaped to receive and engage a stop 232 (FIG. 5) of the oval intermediate portion 230 (FIG. 5) of the offset adapter 200 (FIG. 5). Two circular threaded cavities 190 are provided and employed in the manufacture of the humeral head 100.

[0063] The cavity 130 may include a concave opening 150 defining an axis A5 that is offset and eccentric with respect to the central axis A4 of the humeral head 100. The concave opening 150 is operable to receive the projection 250 (FIG. 5) of the offset adapter 200 when the first tapered cylindrical portion 210 (FIG. 5) of the offset adapter 200 and the projection 250 (FIG. 5) are placed and received in the recess 150 within the tapered cavity 130 of the humeral head 100.

[0064] Referring again to FIGS. 2 and 3, in this illustrated embodiment, the humeral anchor 300 may be a humeral stem anchor. The humeral anchor 300 may include a first proximal portion or base 310 and a second portion or stem 320. As shown in FIG. 2, the base 310 may include an outer ring 312 and a recess 314 having a cavity 350 disposed therein. The base 310 may be configured as a ring or surface area for assisting fixation, for example, the base 310 may contact the cancellous bone to better support the postoperative of the humeral head implant system 10 (FIG. 1). The stem 320 may include fins, legs, or elongated protrusions 322 that extend away from at least one inner surface. The fin 322 may be disposed, for example, at the midpoint or midline of the stem 320. The stem may have, for example, a T-shaped cross-section. The stem 320 may be tapered, for example, to extend in a direction away from the base 310. In other embodiments, the humeral anchor may be a stemless humeral anchor. Humeral stem anchors and humeral stemless anchors suitable for use in the humeral head implant system of the present disclosure may include the humeral stem anchors and humeral stemless anchors described in International Patent Application Publication No. WO2020 / 023971 by Hodorek et al., the entire subject matter of which is hereby incorporated by reference.

[0065] FIG. 9 is a view showing an offset adapter 200 fixed to the humeral head 100 according to an embodiment of the present disclosure. As shown, the position of the protrusion 250 (FIG. 5) with respect to the first axis A1 (FIG. 5) of the first tapered cylindrical portion 210, and the position of the protrusion 250 with respect to the second axis A2 (FIG. 5) of the second tapered cylindrical portion 220 are operable to provide a central axis A4 of the humeral head 100 disposed eccentrically with respect to the axis A2 of the second portion 220 of the offset adapter 200. Thus, as shown in FIG. 10, the humeral head 100 can be disposed eccentrically with respect to the base 312 of the humeral anchor 300. For example, as shown in FIG. 11, the central axis A4 of the humeral head 100 may be offset from the central axis A5 (also shown in FIGS. 2) of the humeral anchor 300, and when the offset adapter 200 is fixed to the humeral anchor 300, the axis A2 of the offset adapter 200 is aligned with the central axis A5 of the humeral anchor 300. As will be described in more detail below, a plurality of offset adapters 200 may be provided in a kit that is differently arranged to allow the protrusions to be more, less, or completely eccentric with respect to the central axis of the humeral head 100 and the central axis of the humeral anchor 300.

[0066] As shown in FIG. 12, a plurality of offset adapters 201, 202, 203, and 204 may be provided for use by a surgeon in selecting a desired eccentricity of the humeral head 100 relative to the humeral anchor 300 in accordance with an embodiment of the present disclosure. For example, the offset adapter 201 may be operable to center (no eccentricity) or align the central axis of the humeral head 100 with the central axis of the cavity of the humeral anchor 300. The offset adapter 202 may be operable for low eccentricity or 1 millimeter (mm) of eccentricity. The offset adapter 203 may be for operation with medium eccentricity or 2 mm of eccentricity. The offset adapter 204 may be for operation with high eccentricity or 3 millimeters of eccentricity. As shown in FIG. 13, the offset adapters 201, 202, 203, and 204 may be essentially identical except that the protrusions 250 are arranged at different angular positions, such as B1, B2, B3, and B4, relative to the offset upper and lower portions of the offset adapters 201, 202, 203, and 204, respectively. FIG. 14 is a view showing the offset adapters 201, 202, 203, and 204 fixed to the humeral head 101. The markings 205, 206, 207, and 208 are respectively disposed on the distal ends (or sides) of the offset adapters 201, 202, 203, and 204 and may be alignable with the indications "C", "L", "M", and "H" on the humeral head 101.

[0067] As further described below, prior to final installation for fixing the humeral head implant system 10 to the resected proximal humerus 12, the eccentrically disposed humeral head 100 may be rotated or aligned relative to the resected proximal humerus 12. For example, the outer peripheral portion of the humeral head may be marked and aligned with the outermost position of the proximal portion of the resected femur.

[0068] Referring to FIG. 15, in this exemplary embodiment, the trial humeral head system 11 may include a trial humeral head 400, a pin guide 500, and a trial offset adapter 600 according to an embodiment of the present disclosure. As will be described in more detail below, the trial humeral head 400 and the pin guide 500 are used to attach the humeral anchor 300, and the trial humeral head 400 and the trial offset adapter 600 are used to trial the trial humeral head 400 and select the appropriate offset adapter 200.

[0069] As shown in FIG. 16, the trial humeral head 400 and the pin guide 500 are assembled and positioned on the resected proximal portion of the patient's humerus 12 to guide the pin 700 into the cancellous bone 13 of the resected humerus 12.

[0070] Referring to FIGS. 17 and 18, the trial humeral head 400 may include a first portion 410 and a second portion 420. The first portion 410 of the trial humeral head 400 may have an articular surface 412. The second portion 420 of the trial humeral head 400 may be a connecting portion having a second or bottom surface 422 (FIG. 18) located on the side opposite the articular surface 412.

[0071] The articular surface 412 may be a convex surface such as the surface of a hemisphere of a spherical cap, or alternatively, a non-spherical cap. The first portion 410 and the second portion 420 of the trial humeral head 400 may define a central axis A6 extending from the first portion 410 to the second portion 420 of the trial humeral head 400. The second portion or connecting portion 420 may be configured to receive not only the pin guide 500 but also the trial offset adapter 600 (FIG. 15).

[0072] As shown in FIGS. 19 and 20, the trial humeral head 400 may include a central opening 450 that extends from a first portion 410 (FIG. 19) to a second portion 420 (FIG. 20). An oval opening 455 may extend from the first portion 410 (FIG. 19) to the second portion 420 (FIG. 20) and may be disposed adjacent to the central opening 450.

[0073] As shown in FIGS. 20 and 21, the second or coupling portion 420 may include an eccentric cavity 440 defined by a plurality of resilient fingers 460 having, for example, a proximal portion 462 (FIG. 21) and a distal portion 464 (FIG. 21). The distal portion includes a protrusion 465 (FIG. 21) that extends inwardly. An annular channel 470 is disposed around the plurality of resilient fingers 460. The annular channel 470 extends from the proximal portion of the finger to the distal portion of the finger. The annular channel 470 allows the plurality of fingers 460 to flex outwardly to releasably connect to the pin guide 500 (FIG. 15) and to the trial offset adapter 600 (FIG. 15) in a snap-fit manner.

[0074] The second or coupling portion 420 may include a concave ledge 480 that extends in a peripheral direction surrounding the annular channel 470 and the concave cavity 440. The concave ledge 480 may be sized and shaped to receive the peripheral portions of, for example, the guide pin 500 and the trial offset adapter 600.

[0075] The concave ledge 480 may include a planar portion 482, a first angled or inclined portion 484 (best shown in FIG. 21), and a second angled or inclined portion 486. The concave ledge 480 may include a plurality of radially outwardly extending semi-circular portions 485 for use in positioning and orienting the trial offset adapter 600 (FIG. 15) as described below. The concave ledge 480 may include indicia disposed adjacent to the plurality of radially outwardly extending semi-circular portions 485. The indicia may be the letter "C" for identifying center eccentricity or zero eccentricity, the letter "L" for identifying low eccentricity, the letter "M" for identifying medium eccentricity, and the letter "H" for identifying high eccentricity. The concave ledge 480 may include a radially outwardly extending rectangular portion 487 (FIG. 20) for use in positioning and orienting the pin guide 500 relative to the trial humeral head 400 in a single fixed position and orientation as described below.

[0076] Referring again to FIGS. 17 and 18, the pin guide 500 can include an elongate member 510 and an outwardly extending member 520. The elongate member 510 includes a first end or upper end 512 and a second end or lower end 514. The lower end 514 of the elongate member 510 is fixed to the outwardly extending member 520. A passageway 530 extends through the elongate member 510 from the first end 512 to the outwardly extending member 520.

[0077] As shown in FIGS. 17 and 22, the outwardly extending member 520 may have an upper inner disk 522. The upper inner disk 522 is disposed eccentrically compared to the elongate member 510 and the passageway 530. Referring to FIGS. 22 and 23, the outwardly extending member 520 may have a generally circular outer periphery 550 having an outwardly extending tab 560 and an inwardly extending notch 570.

[0078] Figures 24 and 25 illustrate the assembled trial humeral head 400 and trial offset adapter 500. The upper inner disk 522 (FIG. 25) is disposed eccentrically between the fingers 460 as compared to the elongated member 510 (FIG. 25) and the passage 530. The outwardly extending member is releasably fixed in the eccentric cavity of the trial humeral head 400 with the elongated member 510 extending through the opening of the trial humeral head 400 and the passage 530 of the pin guide 500 being concentric with the central axis of the trial humeral head 400.

[0079] As shown in FIG. 26, in this exemplary embodiment, according to an embodiment of the present disclosure, the trial humeral head 400 and the trial offset adapter 600 (FIG. 15) may be operably connected to the humeral anchor 301 and positioned at the resected proximal portion of the patient's humerus 12. The trial humeral head 400 and the trial offset adapter 600 (FIG. 15) are used to trial the humeral head 100 (FIG. 1) and select an appropriate offset adapter 200.

[0080] Referring to FIGS. 27 and 28, the second or coupling portion 420 (FIG. 28) of the trial humeral head 400 may be configured to receive the trial offset adapter 600.

[0081] The trial offset adapter 600 may include a body 601 having a generally disk-shaped member 630 extending outwardly from the center, an upper inner ring 640, and a lower tapered portion 650. As shown in FIGS. 29 and 30, the passage 660 extends through the trial offset adapter 600 from the upper inner ring 640 to the lower tapered portion 650 (FIG. 30).

[0082] The outwardly extending member 630 may have a generally circular outer peripheral portion 635 having an outwardly extending detent 637 and an inwardly extending cutout 670. As shown in FIG. 29, the upper inner ring 640 is disposed eccentrically compared to the central outwardly extending generally disc-shaped member 630 and passage 660. As shown in FIG. 30, the lower tapered portion 650 is disposed eccentrically compared to the central outwardly extending generally disc-shaped member 630 and passage 660. The curved channel 680 extends through the central outwardly extending generally disc-shaped member 630 and can enable the detent 637 to be movable inwardly.

[0083] FIGS. 31 and 32 illustrate the assembled trial humeral head 400 and trial offset adapter 600. The upper inner ring 640 (FIG. 32) is disposed between the plurality of fingers 460 (FIG. 32). The generally disc-shaped member 630 extending outwardly is releasably fixed to the concave ledge 480 (FIG. 21) extending in the outer peripheral direction of the trial humeral head 400 with the lower tapered portion 650 extending downward. The annular channel 470 (FIG. 32) enables the plurality of fingers 460 to bend outward and be releasably connected to the trial offset adapter 600 (FIG. 15) in a snap-fit manner and to be releasably connected to the trial offset adapter 600 (FIG. 15) in a snap-fit manner. As shown in FIG. 31, the trial humeral head 400 may include an indication 490 such as the letter "E" and an arrow indicating the rotational direction of the trial offset adapter 600 with respect to the trial humeral head 400 so that the trial offset adapter 600 can be detached from the trial humeral head 400. When the trial offset adapter 600 is rotated sufficiently in the direction R, the generally circular outer peripheral portion 635 of the outwardly extending member 630 engages the ramp 484 and the detent 637 engages the ramp 486 to force the upper disk 640 of the trial offset adapter 600 to pop out from the resilient fingers 460 (FIG. 32).

[0084] The trial humeral head 400 is used to determine the required curvature and diameter of the resected proximal portion of the patient's humerus 12. The trial offset adapter 600 is rotatable or dialable by engaging a detent 637 with one of four radially outwardly extending semi-circular portions 485 (FIG. 31) having indicia such as the letter "C" to identify central eccentricity or zero eccentricity, the letter "L" to identify low eccentricity, the letter "M" to identify medium eccentricity, and the letter "H" to identify high eccentricity.

[0085] As shown in FIG. 33, the trial offset adapter 600 is rotated relative to the trial humeral head 400 using a hexagonal tool 800 such that the detent 637 (FIG. 31) clicks into one of the four radially outwardly extending semi-circular portions 485 and such that the lower tapered portion 650 (FIG. 32) is disposed at a different eccentricity relative to the central axis of the trial humeral head 400. The surgeon can select the degree of eccentricity and assemble it to the humeral anchor 300 (FIG. 1), and remove it as needed to adjust the eccentricity of the trial humeral head 400 relative to the trial offset adapter 600. When the desired eccentricity is achieved, the offset and the orientation of the trial humeral head 400 may be recorded. For example, the offset may be centered or without eccentricity, or low, medium, or high eccentricity. The orientation of the trial humeral head 400 may employ an indicator 495 (FIG. 19) disposed at the periphery of the outer surface of the trial humeral head 400 that is aligned with the outermost position of the resected proximal portion of the patient's humerus 12. The correct humeral head size can be selected based on the diameter and thickness previously used in the trial.

[0086] FIG. 34 is a view showing a humeral head sizer 900 disposed on the resected proximal portion of the humerus 12 of a patient according to an embodiment of the present disclosure. As shown in FIGS. 35 and 36, the humeral head sizer 900 may include a handle 910 and a base plate 920. The distal ends 914 of the handle 910 and the base plate 920 may include a passage 930 extending therethrough. The passage 930 is extensible over a pin 700 (FIG. 34). The surgeon can select the largest size implant based on the size of the base plate 920 appropriate for the patient's anatomy, taking care not to place the periphery of the base plate 920 on the resected cortical bone. It is desirable that the outside of the humeral head sizer 900 be selected to cover most of the cancellous bone without including the cortex. For example, it may be desirable to allow a 5 mm bone ring from the outside of the cortex to the peripheral edge of the humeral head sizer of the base plate 920 for proper sizing of a humeral anchor 300, such as a humeral stemmed anchor or a humeral stemless anchor.

[0087] Figure 37 shows a surgical method 1000 for sizing the humeral head relative to a humeral anchor, which is disposable at the proximal portion of the patient's humerus. The method 1000 includes, for example, at 1100, assembling a trial humeral head and a pin guide; at 1200, positioning the trial humeral head and the pin guide relative to the resected humerus; at 1300, inserting a pin through the pin guide into the resected humerus; at 1400, removing the trial humeral head and the pin guide from the resected humerus and the attached pin; at 1500, forming a cavity in the resected humerus using the pin; at 1600, removing the pin from the resected humerus; at 1700, removing the pin guide from the humeral head; at 1800, attaching an offset adapter to the humeral head; at 1900, selecting the eccentricity of the offset adapter relative to the humeral head to adjust the position of the humeral head relative to the humeral resection; at 2000, using the tapered cylindrical portion of a trial offset adapter disposed in the cavity of the humeral anchor disposed in the resected humerus to confirm the position relative to the resected humerus and placing the assembled trial offset adapter and the trial humeral head on the resected humerus; and at 2100, selecting the humeral head and the offset adapter based on the assembled trial humeral head and the trial offset adapter.

[0088] From this specification, it is understood that the disclosed technique of using a humeral head and an offset adapter employing a peg-in-hole system provides a cost-effective and intuitive humeral head implant system. This technique provides a rapid and inexpensive humeral head implant system that enables addressing and determining the eccentricity of the humeral head relative to the resected proximal portion of the patient's humerus.

[0089] With this technique, the surgeon can select the eccentricity in an unconfusing manner, prevent the taper from being inserted upside down, and is cost-efficient. For example, this technique enables the surgeon to adjust the eccentricity without displacement.

[0090] Conventional humeral heads have a predetermined diameter and thickness to address and reproduce normal human anatomy. However, having each of several different eccentricities of humeral heads requires excessive inventory. The present technology provides a reduced number of predetermined humeral heads, along with an offset adapter that enables a surgeon to select and customize the eccentricity of the humeral head to replicate the presented anatomy of each patient.

[0091] For example, with a pin guide for positioning the pins and a trial offset adapter for determining the eccentricity, the same trial humeral head can be utilized to provide several options to the surgeon while minimizing the amount of instrumentation required during total shoulder arthroplasty and can be used in both steps.

[0092] As will be appreciated by those skilled in the art based on the teachings herein, numerous changes and modifications can be made to the above-described and other embodiments of the present disclosure without departing from the scope of the disclosure. The implants, screws, and other components of the apparatus and / or system disclosed herein, including the accompanying summary and drawings, may be replaced by alternative components or features, such as those disclosed in other embodiments that perform the same, equivalent, or similar functions for the intended purpose, as are known to those skilled in the art. Further, the apparatus and system may include more or fewer components or features than the embodiments described and illustrated herein. Accordingly, this detailed description of the presently preferred embodiments is to be received as illustrative rather than limiting of the present disclosure.

[0093] The terms used in this specification are for the purpose of describing particular embodiments only and are not intended to limit the present disclosure. As used in this specification, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprise" (and any form of comprise such as "comprises", "comprising", etc.), "have" (and any form of have such as "has", "having", etc.), "include" (and any form of include such as "includes", "including", etc.), and "contain" (and any form of contain such as "contain", "containing", etc.) are further understood to be open-ended linking verbs. As a result, a method or apparatus that "comprises", "has", "includes", or "contains" one or more steps or elements holds those one or more steps or elements but is not limited to holding only those one or more steps or elements. Similarly, a step of a method or an element of an apparatus that "comprises", "has", "includes", or "contains" one or more features owns those one or more features but is not limited to owning only those one or more features. Further, an apparatus or structure configured in a certain way is at least configured in that way but may also be configured in ways not described.

[0094] The present disclosure has been described with reference to preferred embodiments. It will be understood that the embodiments of the architecture and operations described herein are examples of multiple possible arrangements for providing the same general features, characteristics, and general system operations. Modifications and changes will occur to others upon reading and understanding the foregoing detailed description. The present disclosure is intended to be construed as including all such modifications and changes.

Claims

Claim 1 A humeral head implant system, comprising: A humeral head having a first portion and a second portion, wherein the first portion has an articular surface, and the first portion and the second portion define a central axis extending from the first portion to the second portion, and the second portion has a surface having a tapered cavity therein, the cavity having a recess therein, and the cavity defining an axis that is eccentrically disposed with respect to the central axis of the humeral head; a humeral head; An offset adapter having a first tapered cylindrical portion having a first axis and a second tapered cylindrical portion having a second axis, wherein the first axis is eccentrically disposed with respect to the second axis, and a distal end of the first tapered cylindrical portion of the offset adapter includes a protrusion offset from the first axis of the first tapered cylindrical portion and the second axis of the second tapered cylindrical portion of the offset adapter; an offset adapter; A humeral anchor having a tapered cavity defining a central axis; and The first tapered cylindrical portion of the offset adapter is received in the tapered cavity of the humeral head such that the protrusion is received in the recess of the tapered cavity of the humeral head; The second tapered cylindrical portion of the offset adapter is received in the cavity of the humeral anchor. A humeral head implant system. Claim 2 The humeral head implant system according to claim 1, wherein an angular position of the protrusion with respect to the first axis of the first tapered cylindrical portion and the second axis of the second tapered cylindrical portion of the offset adapter is operable to eccentrically dispose the central axis of the humeral head with respect to the central axis of the humeral anchor. Claim 3 The offset adapter comprises a plurality of the offset adapters; Each of the plurality of offset adapters includes a protrusion disposed at a different angular position with respect to the first axis of the first tapered cylindrical portion and the second axis of the second tapered cylindrical portion; The humeral head implant system according to claim 1, wherein the plurality of offset adapters are operable such that the central axis of the humeral head is eccentrically disposed differently with respect to the central axis of the humeral anchor. Claim 4 When the proximal humeral head is assembled to the offset adapter, the angular position of the protrusion relative to the first axis of the first tapered cylindrical portion and the angular position of the recess relative to the first axis are operable such that the central axis of the proximal humeral head is concentric with the central axis of the humeral anchor. The proximal humeral head implant system according to claim 1.

5. The offset adapter and the proximal humeral head include an indicator related to the relative amount of eccentricity between the proximal humeral head and the second tapered cylindrical portion of the offset adapter when assembled. The proximal humeral head implant system according to claim 4.

6. The proximal humeral head implant system according to claim 1, wherein the proximal humeral head includes an indicator for use in aligning the proximal humeral head with the resected proximal humerus.

7. The proximal humeral head implant system according to claim 1, wherein the humeral anchor includes at least one of a stem or a stemless.

8. An offset adapter for operably connecting a proximal humeral head to a humeral anchor, the offset adapter comprising: a first tapered cylindrical portion having a first axis; and a second tapered cylindrical portion having a second axis, wherein the first axis is eccentrically disposed relative to the second axis of the offset adapter, and a distal end of the first tapered cylindrical portion includes a protrusion having a third axis offset from the first axis of the first tapered cylindrical portion of the offset adapter and from the second axis of the second tapered cylindrical portion of the offset adapter. The offset adapter.

9. The angular position of the protrusion relative to the first axis of the first tapered cylindrical portion and the second axis of the second tapered cylindrical portion is operable such that the central axis of the proximal humeral head is eccentrically disposed relative to the central axis of the humeral anchor. The offset adapter according to claim 8.

10. The offset adapter includes a plurality of the offset adapters, each of the plurality of offset adapters includes a protrusion disposed at a different angular position relative to the first axis of the first tapered cylindrical portion and relative to the second axis of the second tapered cylindrical portion. The offset adapter according to claim 8, wherein the plurality of the offset adapters are operable to be arranged eccentrically so that the central axis of the humeral head is different from the central axis of the humeral anchor.

11. The offset adapter according to claim 8, including an indicator alignable with the humeral head to indicate an amount of eccentricity between the humeral head and the second tapered cylindrical portion of the offset adapter when assembled.

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