Humeral reconstruction system and use method
The humerus prosthesis with a spherical outer surface and tapered surfaces addresses the challenges of accurately fitting humeral implants in shoulder arthroplasty, enhancing joint mobility and reducing pain.
Patent Information
- Application Number
- JP2024168884
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-09-28
- Filing Date
- 2024-09-27
- Publication Date
- 2025-04-17
AI Technical Summary
Current shoulder arthroplasty techniques face challenges in accurately determining the appropriate length and tilt angle of humeral implants, leading to potential misfit and reduced mobility in the shoulder joint.
The development of a humerus prosthesis with a prosthesis body featuring a spherical outer surface, tapered anterior and posterior surfaces, and a unique arrangement of suture openings to facilitate precise fitting and soft tissue attachment.
This solution enables more accurate measurement and fitting of humeral implants, improving joint mobility and reducing pain by ensuring a better match between the prosthesis and the patient's anatomy.
Smart Images

Figure 2025065031000001_ABST
Abstract
Description
[Technical field]
[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of the filing date of U.S. Provisional Patent Application No. 63 / 586,016, filed September 28, 2023, the disclosure of which is incorporated herein by reference. [Background technology]
[0002] Over time and through repeated use, bones and joints can become damaged or worn down. For example, repetitive strain on bones and joints (e.g., through athletic activities), traumatic events, and certain diseases (e.g., arthritis) can wear down cartilage in joint areas that normally provide a cushioning effect. When cartilage wears down, water can accumulate in the joint area, resulting in pain, stiffness, and reduced mobility. The same can happen if tendons in a joint become loose or soft tissue in (or adjacent to) a joint becomes damaged or worn down.
[0003] Arthroplasty can be used to repair such damaged joints. During a typical arthroplasty, an arthritic or otherwise dysfunctional joint can be reconstructed or realigned. A prosthesis or multiple prostheses can be implanted to repair the damaged area(s). Arthroplasty can be performed in any of many different areas of the body, such as, for example, the knee, hip, shoulder, or elbow. One type of arthroplasty is shoulder arthroplasty, in which a damaged shoulder joint can be replaced with one or more prosthetic implants. The shoulder joint can be damaged, for example, by arthritis (e.g., severe osteoarthritis or osteoarthritis), trauma, or destructive joint disease.
[0004] A typical anatomical shoulder replacement attempts to mimic the anatomical condition. For example, a humeral stem and humeral head replacement is attached to the humerus of the arm to replace the humeral side of the shoulder joint that is arthritic, has suffered trauma, or otherwise requires replacement to improve the patient's condition. The humeral head replacement may articulate with the natural glenoid or may articulate with an implant in the opposing prosthetic glenoid.
[0005] For more severe cases, a reverse reconstruction may be performed, which involves reversing the kinematics of the shoulder joint. A reverse shoulder prosthesis may be created by anchoring a hemispherical device (sometimes called a glenosphere) to the glenoid cavity and implanting a humeral stem having a socket or cup capable of accepting the glenosphere.
[0006] Prior to implanting the humeral implant, it may be desirable to trial the humeral implant to determine the appropriate length of the stem, the appropriate inclination angle of the articulating head, and / or the size of the articulating head, or other characteristics of the implant. The trial humeral implant may be assembled and then inserted into the humerus. The entire trial implant may then be removed and the final humeral implant may be selected and implanted into the bone. Even before starting assembly of the trial prosthesis, it may be desirable to have a tool to assist in measuring the height between the proximal humeral resection and the center of the glenoid cavity to determine the desired height of the prosthesis. Summary of the Invention
[0007] In one aspect of the present disclosure, a humeral prosthesis for replacing a proximal humerus can include a prosthesis body that can include a lateral surface, a medial surface, an anterior surface, a posterior surface, and a first superior surface. The lateral surface can have a spherical curvature. The anterior and posterior surfaces can each be flat and can intersect with the first superior surface, the lateral surface, and the medial surface, respectively. A first bore can extend through the first superior surface and into the prosthesis body. The prosthesis body can also include a plurality of suture openings.
[0008] Additionally, the plurality of suture openings can include a first suture opening and a second suture opening. The first suture opening can define a first suture opening axis, and the second suture opening can define a second suture opening axis. The first axis and the second axis can intersect at an angle Θ. The angle Θ can be an oblique angle. By way of example, the angle Θ can be between 20 degrees and 60 degrees.
[0009] Additionally, the front and rear faces may be tapered inwardly in a superior-to-inferior and lateral-to-inner direction. The front and rear faces may each include a porous patch. The porous patch of each of the front and rear faces may be surrounded by a non-porous portion. Additionally, the porous patch may be one of flush with the non-porous portion and recessed relative to the non-porous portion.
[0010] Further, the anterior surface can intersect the lateral surface at a first rounded edge and the posterior surface can intersect the lateral surface at a second rounded edge. The lateral surface can be curved in at least one plane and can intersect with the first upper surface.
[0011] Continuing with this aspect, the body may further include a second upper surface that may intersect with the first upper surface and the outer surface. The first upper surface and the second upper surface may each be flat. The first upper surface may also be obliquely inclined with respect to the longitudinal axis of the body, and the second upper surface may be oriented perpendicular to the longitudinal axis of the body. In addition, the body may further include a second bore extending through the first upper surface and through the entire body. The first bore and the second bore may intersect. The first bore and the second bore may each be a smooth bore. Alternatively, the first bore may include a plurality of scallops arranged about a central axis of the first bore. Each scallop may be rotationally offset by an angle α with respect to an adjacent scallop. The angle α may be, for example, 5 degrees to 45 degrees. The body may further include a distal surface, which may be flat. The body can further include a tapered strut that can extend from the distal face. Additionally, the body can include a pair of inner legs and a pair of outer legs. Each outer leg can be offset from and parallel to a corresponding inner leg. A slot can extend entirely through each outer leg in a direction toward the inner leg.
[0012] The prosthesis may further include a spacer. The spacer may have a first porous ring and a first spacer suture opening and a second spacer suture opening. The first spacer suture opening may be disposed adjacent to an upper portion of the first porous ring. The second spacer suture opening may be disposed adjacent to a lower portion of the first porous ring. The first spacer suture opening may define a first spacer suture opening axis, and the second spacer suture opening may define a second spacer suture opening axis, and the first spacer suture opening axis and the second spacer suture opening axis may extend parallel to one another. The spacer may include a second porous ring and a third spacer suture opening and a fourth spacer suture opening. The third spacer suture opening may be disposed adjacent to an upper portion of the second porous ring. The fourth spacer suture opening may be disposed adjacent to a lower portion of the second porous ring. The third spacer suture opening can define a third spacer suture opening axis, the fourth spacer suture opening can define a fourth spacer suture opening axis, and the first spacer suture opening axis and the second spacer suture opening axis can extend perpendicular to the third spacer suture opening axis and the fourth spacer suture opening axis.
[0013] The prosthesis can also include a stem component that can have an adaptor and a stem that can extend distally from the adaptor. The stem can include a first stem portion and a second stem portion. The first stem portion and the second stem portion can be radially movable between a first position and a second position.
[0014] In another aspect of the disclosure, a system for replacing a proximal humerus can include a prosthesis body that can include a first bore extending through a first superior surface, an anterior surface, a posterior surface, a lateral surface, a medial surface, and the first superior surface. The first bore can have a plurality of scallops arranged about a central axis of the first bore. The system can also include an articulating trial component that can include a trial body and a boss that can extend from the trial body. The trial body can have an articulating surface disposed thereon. The boss can be configured to be received within the first bore, can extend radially outward therefrom, and can have a protrusion that can be configured to engage one of the scallops.
[0015] Additionally, the trial body can include a central axis and the boss can define a boss axis. The central axis can be offset from the central axis and the prosthesis body can include a midline plane that bisects the prosthesis body and can extend in a superior-inferior direction and a medial-lateral direction. The articulating trial component can have a first eccentric orientation relative to the prosthesis body, in which the projection can engage the first scallop and the central axis of the trial body and the boss axis can be coplanar with the midline plane. The articulating trial component can also have a second eccentric orientation relative to the prosthesis body, in which the projection can engage the second scallop and the boss axis can be coplanar with the midline plane and the central axis of the trial body can be offset in one of an anterior direction and a posterior direction with respect to the midline plane. The trial body can include a central opening, which can be coaxial with a central axis of the trial body, and the through bore can extend through the trial body and the boss. The through bore can be coaxial with the boss axis.
[0016] Additionally, the articular surface can be a concave articular surface. Alternatively, the articular surface can be a convex articular surface. Additionally, the prosthesis body can have a second bore extending entirely through the prosthesis body. The system can also include a trial adaptor disposed within the second bore and can have a flange that can partially define the first bore of the prosthesis body. A scallop can be disposed within the flange.
[0017] In a further aspect of the present disclosure, a bone clamp assembly for resecting a proximal humerus can include a first member, which can have a first handle and a first jaw. The clamp assembly can also include a second member, which can be pivotally connected to the first handle and can have a second handle and a second jaw. Additionally, the assembly can include a resection guide, which can be connectable to the second jaw. The resection guide can have at least one of a captured guide slot and a non-captured guide surface.
[0018] The second jaw may also include a first opening that may extend therein. The resection guide may include a first post that may extend therefrom and may be configured to be received within the first opening. The resection guide may include a second post, and the second jaw may include a movable plunger that may extend from a free end thereof and may have a capture slot extending therein. The second post may be receivable within the capture slot. The second jaw may include a spring, and the plunger may be movable between a first position and a second position. The spring may bias the plunger toward the first position. The plunger may include a cam surface, and the first post of the resection guide may define an axis of rotation about which the resection guide rotates, and the second post may be configured to engage the cam surface when the resection guide is rotated in a first direction about the axis of rotation, thereby moving the plunger from the first position to the second position. The plunger can include a protrusion that can extend into the capture slot, and the second post can have a notch configured to receive the protrusion when the second post is positioned in the capture slot.
[0019] The first jaw can have a first row of teeth that can extend along an arcuate path, and the second jaw can include a first row of teeth that form a "V" shape. The second jaw can include a second row of teeth that can form a "V" shape. The bone clamp can define a first axis that can extend along the length of the handles and be equidistant between the handles, and a second axis that can extend along the length of the jaws and be equidistant between the jaws. The first can intersect the second axis at an angle β. The angle β can be between 120 degrees and 140 degrees, as one example. The angle β can be 130 degrees, as another example.
[0020] In a further aspect of the present disclosure, a method of replacing a proximal portion of the humerus can include clamping a first jaw and a second jaw of a clamp assembly to a humeral shaft, guiding a bone saw through a captured guide slot or along a non-captured guide surface of a resection guide of the clamp assembly to resect the proximal portion of the humerus, and inserting a stem component of a humeral prosthesis into the humeral shaft. The humeral prosthesis can include a prosthesis body and one or more spacers connected to the prosthesis body and the stem component.
[0021] Additionally, the clamping step can include engaging a first jaw with a posterior aspect of the humeral shaft and engaging a second jaw with an anterior aspect of the humeral shaft. The method can also include connecting the resection guide to the second jaw by inserting a first post into a first opening in the second jaw and rotating the resection guide in a first direction until a second post of the resection guide is received in a slot of the second jaw. The method can also include connecting the articulating trial component in a first eccentric arrangement, in which a boss of the articulating trial component is received in a first bore of the prosthesis body and a protrusion of the boss engages a first scallop that at least partially defines the first bore. The articulating trial component can have a trial body and an articular surface disposed on the trial body. The method can also include rotating the joint trial component to a second eccentric configuration, where a protrusion on the boss can engage a second scallop that at least partially defines the first bore. Further, the method can include connecting one or more spacers to the stem component and the prosthesis body via a taper lock connection.
[0022] The method may further include connecting one or more spacers to the stem component and the prosthesis body via a snap-fit connection. Additionally, the method may include passing a suture through the first suture opening and the second suture opening in the one or more spacers and passing the soft tissue through the first suture opening and the second suture opening and pressing the soft tissue against the porous structure between the first suture opening and the second suture opening via the suture. The method may also include connecting an anatomy tracker to the bone clamp and registering the humerus to a computer-aided surgical system using the anatomy tracker. [Brief description of the drawings]
[0023] [Figure 1A] FIG. 1 is a schematic diagram of a human shoulder joint showing the bones. [Figure 1B] FIG. 1B is a schematic diagram of the humerus of the human shoulder joint of FIG. [Figure 2A] 1B is a perspective view of an exemplary humeral prosthesis according to one embodiment of the present disclosure implanted in the humerus of FIG. 1A and including an exemplary reverse-style joint insert and an exemplary reverse-style insert tray. [Figure 2B] 2B is a front elevational view of an exemplary proximal body according to one embodiment of the present disclosure that may be implemented in the humeral prosthesis of FIG. 2A. [Figure 2C] FIG. 2C is a perspective view of the proximal body of FIG. 2B. [Figure 2D] FIG. 2C is a perspective view of the proximal body of FIG. 2B. [Figure 2E] 2B is a perspective view of an exemplary proximal body according to another embodiment of the present disclosure that may be implemented in the humeral prosthesis of FIG. 2A. [Figure 2F] FIG. 2C is a front elevational view of an exemplary kit of proximal bodies according to one embodiment of the present disclosure, similar to that of FIG. 2B. [Figure 2G] 2B is a perspective view of an exemplary stem component according to one embodiment of the present disclosure that may be implemented in the humeral prosthesis of FIG. 2A. FIG. [Figure 2H]FIG. 2C is a cross-sectional view of the stem component of FIG. 2G taken along its midline. [Figure 2I] 2B is a perspective view of an exemplary implant spacer according to one embodiment of the present disclosure that may be implemented in the humeral prosthesis of FIG. 2A. [Figure 2J] FIG. 2I is a front elevation view of the implant spacer of FIG. 2I. [Figure 2K] FIG. 2I is a front elevation view of an exemplary kit of implant spacers similar to that of FIG. 2I. [Figure 2L] 2B is an exploded view of an exemplary humeral prosthesis according to another embodiment of the present disclosure, similar to that of FIG. 2A. [Figure 2M] FIG. 2B is an elevational view of the assembled humeral prosthesis of FIG. 2A. [Figure 2N] FIG. 2C is a cross-sectional view of the humeral prosthesis of FIG. 2L taken along its midline. [Figure 3A] FIG. 13 is a perspective view of an exemplary proximal body trial adaptor according to one embodiment of the present disclosure; [Figure 3B] FIG. 3B is a side elevational view of the proximal body trial adaptor of FIG. 3A . [Figure 3C] 13 is a partial cross-sectional perspective view of a proximal body trial adaptor within a prosthesis proximal body taken along its midline; FIG. [Figure 4A] FIG. 1 is a perspective view of an exemplary reverse style trial insert according to one embodiment of the present disclosure; [Figure 4B] FIG. 4B is a front view of the reverse type trial insert of FIG. 4A. [Figure 5A] FIG. 1 is a perspective view of an exemplary trial tray according to one embodiment of the present disclosure. [Figure 5B] FIG. 5B is another perspective view of the trial tray of FIG. 5A. [Figure 5C] FIG. 5B is a partial perspective view of the boss of the trial tray of FIG. 5A. [Figure 5D] FIG. 5B is a cutaway view of the trial tray of FIG. 5A assembled with a proximal body trial adapter. [Figure 5E]FIG. 2 is a perspective view of a trial tray assembled to an implant proximal body in a first configuration. [Figure 5F] FIG. 13 is a perspective view of a trial tray assembled to an implant proximal body in a second configuration. [Figure 5G] FIG. 13 is a perspective view of a trial tray assembled to an implant proximal body in a third configuration. [Figure 6A] FIG. 13 is a top perspective view of an exemplary humeral head trial according to one embodiment of the present disclosure. [Figure 6B] FIG. 6B is a bottom perspective view of the humeral head trial of FIG. 6A . [Figure 7] FIG. 1 is a perspective view of an exemplary humeral head coupler according to one embodiment of the present disclosure. [Figure 8A] FIG. 13 is a perspective view of an exemplary humeral head coupler trial according to one embodiment of the present disclosure. [Figure 8B] FIG. 13 is a perspective view of an exemplary humeral head coupler trial according to one embodiment of the present disclosure. [Figure 9A] 5A and 5B are perspective views of an exemplary humeral trial prosthesis according to one embodiment of the present disclosure, implanted in the humerus of FIG. 1A and assembled with the trial tray of FIG. 5A and the trial insert of FIG. 4A. [Figure 9B] 2B is a perspective view of an exemplary proximal trial body according to one embodiment of the present disclosure that may be implemented in the humeral prosthesis of FIG. 2A . [Figure 9C] 2B is a perspective view of an exemplary proximal trial body according to one embodiment of the present disclosure that may be implemented in the humeral prosthesis of FIG. 2A . [Figure 9D] FIG. 9C is a partial side view of the trial proximal body of FIGS. 9B and 9C. [Figure 9E] 13 is a partial perspective view of an exemplary proximal trial body according to another embodiment of the present disclosure. [Figure 9F] 9B is a perspective view of an exemplary trial spacer according to one embodiment of the present disclosure that may be implemented in the humeral trial prosthesis of FIG. 9A. [Figure 9G]9B is a perspective view of an exemplary trial spacer according to one embodiment of the present disclosure that may be implemented in the humeral trial prosthesis of FIG. 9A. [Figure 9H] 9B is a perspective view of an exemplary trial spacer according to one embodiment of the present disclosure that may be implemented in the humeral trial prosthesis of FIG. 9A. [Figure 9I] FIG. 9C is a front elevational view of an exemplary kit of trial spacers, similar to that of FIG. 9F. [Figure 9J] FIG. 9I is an exploded cross-sectional view of a pair of trial spacers from the kit of FIG. 9I. [Figure 10A] 9B is a perspective view of an exemplary expandable trial stem according to one embodiment of the present disclosure that may be implemented in the humeral trial prosthesis of FIG. 9A . [Figure 10B] FIG. 10B is an elevational view of the expansion bolt of the expandable trial stem of FIG. 10A. [Figure 11A] 9B is a perspective view of an exemplary taper protection insert according to one embodiment of the present disclosure that may be implemented in the humeral trial prosthesis of FIG. 9A. [Figure 11B] 9F is a partially exploded view of the taper protection insert assembled with the trial spacer of FIG. 9F together with the stem component of FIG. 2G. [Figure 12A] FIG. 1 is a perspective view of an exemplary bone clamp assembly with a pair of intersecting axes shown superimposed, according to one embodiment of the present disclosure; [Figure 12B] FIG. 12B is a schematic diagram of the pair of intersecting axes of FIG. 12A. [Figure 12C] FIG. 12B is an exploded view of the bone clamp assembly of FIG. 12A. [Figure 12D] 12B is a partial perspective view of the bone clamp assembly of FIG. 12A with the resection guide in a first configuration; [Figure 12E] 12B is a partial perspective view of the bone clamp assembly of FIG. 12A with the resection guide in a second configuration; [Figure 12F] FIG. 12B is a partial perspective view of the bone clamp assembly of FIG. 12A. [Figure 12G]FIG. 12B is a partial perspective view of the bone clamp assembly of FIG. 12A attached to the humerus of FIG. 1B and in conjunction with an oscillating bone saw. [Figure 12H] FIG. 13 is a partial perspective view of an exemplary bone clamp assembly according to another embodiment of the present disclosure. [Figure 12I] FIG. 12H is a top view of the bone clamp assembly of FIG. 12H attached to the humerus of FIG. 1B. [Figure 13] FIG. 1 is a perspective view of an exemplary sounder according to one embodiment of the present disclosure. [Figure 14A] FIG. 1 is a perspective view of an exemplary reamer planar according to an embodiment of the present disclosure. [Figure 14B] FIG. 14B is a partial perspective view of the reamer planar of FIG. 14A. [Figure 15A] FIG. 2 is an elevational view of an exemplary handle according to one embodiment of the present disclosure. [Figure 15B] FIG. 15B is a cross-sectional view of the handle of FIG. 15A taken along its midline. [Figure 15C] FIG. 15B shows the handle of FIG. 15A immediately prior to engagement with the stem component of FIG. 2G. [Figure 15D] FIG. 15B shows the handle of FIG. 15A while in an unlocked position, immediately after engagement with the stem component of FIG. 2G. [Figure 15E] FIG. 15B shows the handle of FIG. 15A after transition to a locked position, immediately after engagement with the implant stem. [Figure 16A] FIG. 1 is a front elevation view of an exemplary height measurement gauge according to an embodiment of the present disclosure. [Figure 16B] 16B is a cross-sectional view of the scale of the height measuring gauge of FIG. 16A taken along line BB. [Figure 16C] FIG. 16B is a perspective view of the height measurement gauge of FIG. 16A without the pointer member. [Figure 16D] FIG. 16B is an enlarged view of the clamp of the height measuring gauge of FIG. 16A. [Figure 17A] FIG. 1 is a perspective view of an exemplary push stand according to one embodiment of the present disclosure. [Figure 17B]FIG. 17B shows the pusher stand of FIG. 17A assembled with the stem component of FIG. 2G. [Figure 18] FIG. 1 illustrates a perspective view of an exemplary tapered separation tool according to an embodiment of the present disclosure. [Figure 19A] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 19B] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 19C] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 19D] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 19E] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 19F] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 19G] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 19H] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 19I] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 19J] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 19K] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 19L] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 19M] 1C shows the individual steps of a method for replacing the proximal portion of the humerus of FIG. 1B. [Figure 20A] FIG. 1 illustrates an exemplary surgical navigation system in accordance with the present disclosure. [Figure 20B]FIG. 20B is a perspective view of an exemplary bone clamp according to an embodiment of the present disclosure that may be implemented in the computer-assisted surgical system of FIG. 20A. [Figure 21] 1 is a perspective view of an exemplary humeral prosthesis according to another embodiment of the present disclosure; [Figure 22] 13 is a perspective view of an exemplary humeral trial prosthesis according to another embodiment of the present disclosure; FIG. [Figure 23A] FIG. 1 is a perspective view of a modular adapter according to one embodiment of the present disclosure. [Figure 23B] 11 is a perspective view of a humeral head trial according to another embodiment of the present disclosure; FIG. [Figure 23C] 23B is an elevational view of a modular humeral head trial assembly including the modular adapter of FIG. 23A and the humeral head trial of FIG. 23B. [Figure 23D] FIG. 23D is a perspective view of the modular humeral head trial assembly of FIG. 23C . [Figure 23E] FIG. 23D is a cross-sectional view of the modular humeral head trial assembly of FIG. 23C taken along its midline. [Figure 24] 23C in a first eccentric position; FIG. 24 is an elevational view of a humeral trial prosthesis assembly including the humeral trial prosthesis of FIG. 22 and the humeral head trial assembly of FIG. 23C in a first eccentric position; [Diagram 25] 13 is an elevational view of the humeral head trial prosthesis assembly in a second eccentric position. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] In the following discussion of certain implantable devices, when reference is made to a particular direction, it should be understood that such direction is described with respect to the orientation and position of the implantable device during an exemplary application to the human body. Thus, as used herein, the term "proximal" refers to a position closer to an individual's heart and the term "distal" refers to a position farther from an individual's heart. The term "inferior" refers to a position closer to an individual's feet and the term "superior" refers to a position closer to an individual's head. The term "anterior" refers to a position closer to the front of the body or face and the term "posterior" refers to a position closer to the back of the body. Additionally, the term "medial" refers to a position closer to the midline of the body and the term "lateral" refers to a position farther from the midline of the body.
[0025] 1A and 1B show the anatomy of a typical glenohumeral joint. The joint is formed in part by a head 51 of the humerus 50 and a glenoid cavity 58 of the scapula 54. The head 51 is a generally spherical, convex structure. The glenoid cavity 58 includes a concave articular surface over which the head 51 moves. As shown in FIG. 1B, the humerus 50 has a proximal portion 53, which is the portion of the humerus 50 adjacent the glenoid cavity 58 and which forms part of the shoulder joint. The proximal humerus 53 is sometimes referred to herein as the upper humerus. If the glenohumeral joint is arthritic, diseased, or damaged, treatment may include making an incision over the joint to provide access to the head 51 of the humerus 50 and the glenoid cavity 58 of the scapula 54. Once the head 51 is accessible, it may be separated from the remainder of the humerus 50 as an initial step in the process of implanting the implant.
[0026] In some circumstances, removal of a significant portion of the proximal humerus or upper humerus 53 may be necessary, which would otherwise be unavailable to support a humeral implant as part of the arthroplasty. For example, in a revision arthroplasty where a previously implanted humeral prosthesis must be removed and replaced with a new humeral prosthesis, a significant portion of the proximal humerus 53 may be unavailable to support the new humeral prosthesis. In another example, significant trauma or disease may require removal of a significant portion of the proximal humerus 53 prior to implantation of a humeral prosthesis. In this regard, this significant portion of the proximal humerus 53 may be removed by resecting the humerus 50 through the humeral shaft 52, such that the bone removed includes a portion of the humeral shaft 52 and the humeral head 51. As a result of removing this bone, soft tissue attachments of the proximal humerus are also removed. Such soft tissues may include the deltoid and the rotator cuff, which is generally made up of the supraspinatus, infraspinatus, teres minor, and subscapularis muscles. To restore function of the glenohumeral joint, the resected proximal humerus 53 can be replaced with a humeral prosthesis.
[0027] 2A shows an exemplary humeral prosthesis 100 implanted in the diaphysis 52 of the humerus 50 after the proximal portion 53 has been resected. The humeral prosthesis 100 is configured to facilitate soft tissue connection to the humeral prosthesis 100 and may include a proximal body 110, a stem component 130, and one or more implant spacers 150 disposed between the proximal body 110 and the stem component 130 to account for the length of bone removed. The humeral prosthesis 100 may also include an articular component 260 that may be configured to articulate with a corresponding component implanted in the scapula 54 to replace the glenoid cavity 58. In the illustrated embodiment, the articular component 260 is an exemplary reverse-type articular component that includes a reverse-type insert tray 262 and a reverse-type articular insert 264 coupled to the reverse-type insert tray 260. The reverse articular insert 264 includes a concave articular surface 266 configured to articulate with a glenosphere (not shown) that may be implanted in the scapula 54. Although the reverse articular component 260 is shown connected to the proximal body 110, it should be understood that the articular component 260 connected to the proximal body 110 may alternatively include a humeral head prosthesis (not shown) that may have a convex articular surface configured to articulate with a concave prosthetic glenoid cavity (not shown) implanted in the scapula 54.
[0028] 2B-2E show an exemplary proximal body or prosthetic body 110 that may be implemented into the humeral prosthesis 100. Although the proximal body 110 typically replaces the proximal end of the humerus 50, the proximal body 110 may not be shaped to perfectly match the bone structure it is intended to replace. Instead, the proximal body 110 may be shaped to optimally interact with soft tissue and sutures, wires, and the like that may be used to secure the soft tissue to the proximal body 110. In this regard, the proximal body 110 may include a number of exterior surfaces that cooperate to form the geometry of the exterior shape of the proximal body 110. In the illustrated embodiment, the proximal body 110 includes a lateral surface 111, a medial surface 114, a first anterior-posterior ("AP") surface 113a, a second AP surface 113b, a first proximal surface 115, a second proximal surface 116, and a distal surface 118.
[0029] The lateral or spherical surface 111 forms the outer end of the proximal body 110. The lateral surface 111 is preferably spherical with a spherical radius of curvature because this geometry promotes atraumatic soft tissue contact and helps maximize the surface area, thereby allowing soft tissue to spread across this surface area to ensure that a functional range of motion is achieved. In other words, the deltoid is a triangular shaped muscle with three heads (i.e., anterior, lateral, and posterior) that extend from their origin at the scapula and clavicle, across the glenohumeral joint, to their collective attachment at the triangular tuberosity, located generally along the humeral shaft 52. These three heads, in conjunction with other soft tissues such as the rotator cuff, pectoralis major, and latissimus dorsi, help provide anterior, lateral, and posterior ranges of motion, respectively, to the humerus 50. The proximal body 110 can be implanted such that the natural deltoid muscle extends along the lateral surface 111 beyond the prosthesis. The spherical geometry of the lateral surface 111 facilitates enveloping the deltoid muscle such that the three heads of the deltoid muscle spread over the lateral surface 111 and remain in their respective anterior, lateral and posterior positions surrounding the proximal body 110, and ensures that the forces generated by such muscles are appropriately directed to provide a desired range of motion. The radius of curvature of the sphere can vary depending on the size of the proximal body 110. For example, the radius of curvature can be between 18 mm and 24 mm.
[0030] The first AP surface 113a and the second AP surface 113b may substantially form the anterior and posterior sides of the proximal body 110, respectively intersecting the lateral surface 111. The proximal body 110 may be utilized in either a right or left shoulder joint, such that the first AP surface 113a and the second AP surface 113b are positioned anteriorly or posteriorly within the patient, respectively, depending on which side of the patient's body the proximal body 110 is implanted on. The first AP surface 113a and the second AP surface 113b are preferably flat surfaces that taper inwardly toward each other from the lateral end of the proximal body 110 toward the medial end of the proximal body 110. In addition, the AP surfaces 113a and 113b taper inwardly from the top to the bottom. In this manner, the AP surfaces 113a and 113b define a double tapered shape of the proximal body 110 that narrows the proximal body 110 in the medial and downward directions.
[0031] Each of the AP faces 113a and 113b may include a porous patch 117 configured with a porous structure. Such porous structure has a porosity configured to promote tissue ongrowth / ingrowth. Porosity is generally a measure of the empty space of a material relative to the total space occupied by the material. In contrast, the portions of the AP faces 113a and 113b surrounding each porous patch 117 have no porosity or a porosity that is substantially zero. In this regard, such seemingly non-porous portions of the AP faces 113a and 113b may be considered solid structures, although it will be recognized that structures that appear non-porous at least to the naked eye may have porosity on a very small scale. Indeed, structures manufactured using additive manufacturing techniques, as may be the case for the proximal body, often have inherent porosity in the material. Thus, as used herein, the terms non-porous and solid refer to having a porosity so small or close to zero that it prohibits tissue growth therein. On the other hand, as used herein, terms such as porous refer to having a porosity large enough to promote tissue in-growth. Each porous patch 117 may have a rough exterior compared to the non-porous surface of the proximal portion 110 due to at least the peaks and valleys formed by its porous nature. In this regard, each porous patch 117 may be formed to be flush with or recessed relative to the surrounding non-porous portions of the AP surfaces 113a and 113b. In other words, the peaks of each porous patch 117 may be flush with or recessed relative to the non-porous portions. The flat geometry of the first 113a and second 113b AP surfaces, along with the flush or recessed configuration of the porous patch 117, helps simplify suturing and also helps provide clearance for the sutures to pass through the porous patch 117 on the first 113a and second 113b AP surfaces so that the sutures do not rub against the porous patch 117 and wear out. However, when tissue is pressed against the AP surfaces 113a and 113b, the tissue comes into contact with the porous patch 117 and promotes in-growth.
[0032] Although the porous patch 117 is shown and described as being located on the AP faces 113a and 113b, the porous patch 117 may be disposed at other locations on the proximal body 110. For example, as shown in FIG. 2E, the implant proximal body 110' can include an outer surface 111' having a porous patch 117 thereon.
[0033] As discussed above, the first and second AP planes 113a, 113b may intersect with the outer surface 111. This may result in a sharp edge at the respective intersection. To help smooth this edge, the edge may be rounded or chamfered to prevent tissue abrasion. In this manner, the proximal body may include rounded edges or surfaces 112a and 112b extending along the respective boundaries between the first and second AP planes 113a, 113b and the outer surface 111.
[0034] The first AP plane 113a and the second AP plane 113b can intersect the lateral surface 111 at an outer end of the proximal body 110, and the AP planes 113a and 113b can also intersect the medial surface 114 at an inner end of the proximal body 110. The medial surface 114 can be curved in one or more planes and can be defined by one or more radii of curvature along the superior-inferior length of the medial surface 114. It should be noted that the maximum radius of curvature of the medial surface 114 is smaller than the radii of curvature defining the lateral surface 111.
[0035] The first and second upper surfaces 115, 116 are each preferably flat surfaces that intersect at an edge 112c, which may be rounded or chamfered. The first upper surface 115 is generally oriented at an oblique angle to the longitudinal axis of the proximal body 110, and the second upper surface 116 is generally oriented perpendicular to the longitudinal axis. In the illustrated embodiment, the first upper surface 115 intersects the inner surface 114 and the first and second AP planes, and the second upper surface 116 intersects the outer surface 111. However, in other embodiments, the first upper surface 115 may also intersect the outer surface 111, and in further embodiments, the second upper surface 116 may also intersect the first and second AP planes 113a, 113b.
[0036] The distal surface 118 is located at the distal end of the proximal body 110, as shown in FIG. 2B, and may be a flat surface. The tapered post 119 may extend from the distal surface 118 and may be conically tapered inwardly in a top-to-bottom direction. The tapered post 119 may facilitate connection with a corresponding tapered bore in another component of the humeral prosthesis 100, such as the implant spacer 150 and / or the implant stem 130. However, other connection mechanisms are contemplated, such as, for example, a screw mechanism or a snap-fit mechanism. In another example shown in FIG. 2E, the proximal body 110' may include a raised distal surface 118' and a tapered opening 119' for receiving the tapered post therein.
[0037] The proximal body 110 may also include a first bore 121 and a second bore 122. As shown in FIG. 2N, the first bore 121 may extend through the first upper surface 115 perpendicular to the first bore 121 and may intersect with the second bore 122 at an oblique angle. The first bore 121 may be a smooth bore or may be tapered to form a taper lock with a corresponding tapered post of an articulating component, such as articulating component 260.
[0038] The second bore 122 may be a smooth bore and may extend vertically through the entire proximal body 110, as best shown in the cross-sectional view of FIG. 2N. In this regard, the second bore 122 may extend through the first proximal face 115 and / or the second proximal face 116 at the top end of the proximal body 110 and through the tapered post 119 at the bottom end. To facilitate access to the second bore 122, a notch or recess 120 surrounding the second bore 122 may extend through the first proximal face 115 and the second proximal face 116, as best shown in FIG. 2C.
[0039] In addition to the porous patch 117, which can promote tissue on-growth / ingrowth into the proximal body 110, the proximal body 110 can also include a number of suture holes or suture channels 124, which can facilitate connection of soft tissue to the proximal body 110 via sutures, wires, and the like. In particular, both the anterior and posterior sides of the proximal body 110 can include a first suture hole 124a and a second suture hole 124b. As shown in FIG. 2B, the first suture hole 124a can extend through the outer surface 111 and the first AP plane 113a, across the boundary 112a thereof. Such suture hole 124a can define an axis A1 extending both laterally-medially and superiorly-inferiorly. The second suture hole 124b can be located more distal than the first suture hole 124a and can extend through the lateral surface 111 and the first AP plane 113a, across the boundary 112a thereof. An axis A2 defined by the second suture hole 124b can extend substantially in a lateral-medial direction. However, in other embodiments, the axis A2 can extend in a superior-inferior ("SI") direction as well as in a lateral-medial ("LM") direction.
[0040] In some embodiments, axis A1 and axis A2 may be coplanar and intersect at an angle Θ, which may be an acute angle, such that axis A1 and axis A2 form an "X" shaped configuration. For example, angle Θ may be 20 degrees to 60 degrees. However, in other embodiments, axis A1 and axis A2 may be offset from one another in the AP direction such that they are not coplanar. In such a configuration, axis A1 and axis A2, although not intersecting, may nevertheless be projected onto a single plane, such as the plane defined by FIG. 2B, to form the same X-shaped configuration as described above. It should be understood that the same configuration of first suture opening 124a and second suture opening 124b is included on the other AP side of proximal body 110 with respect to second AP plane 113b, as shown in FIG. 2B.
[0041] The proximal body 110 can also include a second suture hole 124c and a third suture hole 124d that extend through the medial surface 114 in a substantially AP direction, as best shown in Figures 2B and 2C. Although the proximal body 110 is shown and described as having six suture holes (i.e., two pairs of first suture hole 124a and second suture hole 124b, and third suture hole 124c and fourth suture hole 124d), other embodiments of the proximal body 110 can include more or fewer suture holes 124.
[0042] The X-shape of the cross axes A1, A2 of the first and second suture holes 124a, 124b, alone or in cooperation with the third and fourth suture holes 124c, 124d, facilitates compression of the soft tissue against the porous patch 117. For example, the subscapularis muscle can be sutured to the anterior side of the proximal body 110 and the infraspinatus muscle can be sutured to the posterior side of the proximal body 110. This can be accomplished, for example, by placing such muscles against the porous patch 117 on the first and second AP planes 113a, 113b, respectively, and threading one or more sutures through the first and second openings 124a, 124b on the anterior and posterior sides of the proximal body 110, through one or both of the third and fourth suture openings 124c, 124d at the medial end of the proximal body 110, and over the muscles. One or more sutures in this regard may extend along axis A1 and axis A2 and may traverse the proximal body 110 such that the subscapularis and infraspinatus are pressed by the sutures against the entire patch area of the porous patch 117 on the anterior and posterior sides of the proximal body 110, respectively. In a further example, the supraspinatus may be secured by sutures extending through suture openings 124a and 124b and pressed against the lateral surface 111. The X-shape defined by openings 124a and 124b creates intersecting force vectors extending along axis A1 and axis A2 that help press the supraspinatus against the lateral surface 111 and, if included, against the patch 117 on the lateral surface 111 to promote on-growth / ingrowth of the supraspinatus.
[0043] Additionally, axis A1 and / or axis A2 of the X-shape extend along the flat AP surfaces 113a and 113b, which not only provides the benefits discussed above, such as avoiding abrasion, but also allows the needle to pass through the suture holes 124a and 124b without steps or other material obstructions in its path. In other words, the suture needle passing through both the suture holes 124a and 124b and the soft tissue has a well-defined path due to at least the flatness of the AP surfaces 113a and 113b.
[0044] The kit can include multiple proximal bodies 110, each of different sizes. For example, a kit can be provided that can include two or more proximal bodies 110 of different sizes. In another example, as shown in FIG. 2F, the kit can include a first proximal body 110a, a second proximal body 110b, and a third proximal body 110c, which can be characterized as small, medium, and large. The size differences between the proximal bodies 110a-110c can include differences in AP dimensions and medial-lateral ("ML") dimensions. In addition, each of the differently sized proximal bodies 110a-110c can have an outer surface 111 with a different radius of curvature than the others. For example, the outer surfaces 111 of the first proximal body 110a, the second proximal body 110b, and the third proximal body 110c can have radii of curvature of 18 mm, 20 mm, and 22 mm, respectively. However, in other embodiments, one or more of the proximal bodies 110a-110c can have the same radius of curvature. For example, the outer surface 111 of the first proximal body 110a and the second proximal body 110b can have a radius of curvature of 22 mm.
[0045] 2G and 2H illustrate an exemplary implant stem component 130 according to one embodiment of the present disclosure. In the illustrated embodiment, the stem component 130 is a one-piece stem component including a stem 132 and an adapter 140 integrally connected to the stem 132 to form a monolithic structure. However, in other embodiments, the stem 132 and the adapter 140 can be separate modularly connected components, examples of which are described in U.S. patent application Ser. No. 18 / 189,261 (the "'216 Application"), which is incorporated herein by reference in its entirety.
[0046] The stem 132 is configured to be inserted into the intramedullary canal of the remaining humeral shaft 52. The stem 132 can include features configured to mate with the humeral shaft 52 to inhibit relative rotation therewith. For example, the stem 132 can be configured for a press-fit connection and can include a number of flutes or splines 138, as shown in FIG. 2G, to enhance primary engagement with the bone and rotational resistance. In addition, the stem 130 can include a porous structure to promote in-growth and secondary engagement with the bone. For example, the stem 132 can include a proximal portion 134 and a distal portion 136. The proximal portion 134 can have a porous structure that forms an exterior thereof, and the distal portion 136 can be substantially solid. For example, the porous structure of the proximal portion 134, and all other porous structures described herein, may include an in-growth structure, such as an on-growth structure, such as titanium plasma spraying, or a porous structure formed from an additive manufacturing process, such as 3D printing. The grooves 138 may extend through both the proximal portion 134 and / or the distal portion 136. In other embodiments, the stem 132 may be configured to be cemented into the humeral shaft 52 and may not include a porous structure. However, ridges, grooves, splines, or the like may be provided to facilitate engagement with bone cement and reduce or eliminate rotation of the stem 132 within the humeral shaft 52.
[0047] The adaptor 140 may be a generally cylindrical member and may include a radially projecting distal collar 142 configured to abut the proximal end of the humeral shaft 52. The distal collar 142 may include a distal surface 144 having a porous structure that promotes bone ingrowth from the resected proximal end of the humeral shaft 52. The adaptor 140 may also include a base portion or adaptor body 145 extending proximally from the distal collar 142. As shown in FIG. 2H, a tapered bore 148 may extend into the adaptor body 145 through its proximal end. Such tapered bore 148 may be configured to mate with a tapered post of another component of the humeral prosthesis 100, such as, for example, the tapered post 119 of the proximal body 110. A threaded opening 143 may extend through the distal end of the tapered bore 148. Such threaded opening 143 may be configured to engage threads of such other humeral prosthetic components to aid in their fixation and / or may be configured to connect a removal tool (e.g., a slap hammer), for example, for extraction.
[0048] A connection mechanism may be formed on the exterior of the adapter body 145. For example, the adapter 140 may be configured to connect to an inserter / extractor handle 700, which is described in more detail below. In this regard, the adapter 140 may include opposing flats 149, each extending perpendicular to a longitudinal axis of the stem component 130. The adapter 140 may also be bounded at a distal end by a distal collar 142 and at a proximal end by a proximal collar or shoulder 141, which may have a smaller cross-sectional dimension than the distal collar 142.
[0049] Other connection mechanisms can include mechanisms configured to quickly connect and disconnect to other components, such as, for example, the trial proximal body 310, the trial spacer 350, and the height gauge 800, each of which is described further below. In this regard, the adapter 140 can include two recesses 146, each bounded at its proximal end by a shoulder or protrusion 147 and at its distal end by the outer periphery of the adapter body 145. In the illustrated embodiment, the recesses 146 are rotationally offset from the flat 149 by approximately 90 degrees, although other relative orientations may be suitable in other embodiments.
[0050] To construct the humeral prosthesis 100, one or more spacers 150 can be connected to the proximal body 110 and the implant stem component 130 to achieve a desired height. Figures 2I and 2J show an exemplary implant spacer 150 that can be implemented in the humeral prosthesis 100. The implant spacer 150 can include a spacer body 155 and a tapered post 152 extending distally from the body 155.
[0051] The spacer body 155 may be substantially cylindrical; however, other shapes are contemplated, such as, for example, rectangular. The spacer body 155 may extend from a proximal face 158 to a distal face 159, and the length L of the spacer may be measured from the proximal face 158 to the distal face 159. The length L of the spacer 150 at least partially determines the height of the humeral prosthesis 100, as described further below.
[0052] The spacer body 155 may be substantially formed of a solid metallic material. However, the spacer body 155 may include a plurality of porous rings 156 positioned at regular intervals along its height. For example, as shown, the spacer 150 may include four porous rings 156, namely, a first porous ring 156a, a second porous ring 156b, a third porous ring 156c, and a fourth porous ring 156d. However, the spacer 150 may have more or fewer porous rings 156. For example, a shorter implant spacer 150 may have fewer rings 156, such as one to three rings 156, and a longer spacer 150 may have more rings 156, such as five to eight rings 156. Additionally, although the porous structures are shown and described as rings extending circumferentially around the longitudinal axis of the spacer body 155, other embodiments of the spacer 150 may include porous patches that do not extend completely around the spacer body 155. As discussed above, removal of the proximal humerus 153 may also remove tissue deposits. The porous rings 156 promote reattachment of tissue to the humeral prosthesis 100 via tissue in-growth.
[0053] The spacer body 155 may also include a number of suture openings 153 that may further facilitate attachment of tissue via sutures, wires, and the like. In the illustrated embodiment, the suture openings 153 may be positioned relative to the porous ring 156 such that the suture openings 153 may be used to press tissue against the porous ring to facilitate tissue in-growth. In this regard, a first suture opening 153a may be positioned adjacent to the first porous ring 156a proximally and a second suture opening 156b may be positioned adjacent to the first porous ring 156a distally. The first suture opening 156a may define an axis A3 and the second suture opening 153b may define a second axis A4. Axis A3 and A4 can extend perpendicular to the longitudinal axis of spacer body 155 and can extend parallel to one another. However, in some embodiments, axis A3 and axis A4 can be angled relative to one another so that they intersect. In this configuration of first and second suture openings 153a, 153b and first porous ring 156a, tissue can be sutured proximal and distal to suture ring 156a such that tissue is pressed against porous ring 156a to promote tissue in-growth.
[0054] The first suture opening 153a and the second suture opening 153b are disposed on one side of the spacer body 155, such as the front side. Another pair of the first openings 153a and the second openings 153b may be disposed on the opposite side of the spacer body, such as the rear side of the spacer body, as shown in FIG. 2J. In such a configuration, the axis of the second pair of the first suture openings 153a and the second suture openings 153b may be parallel to the respective axes A3 and A4 of the first pair of the first suture openings 153a and the second suture openings 153b. However, in some embodiments, the second pair of suture openings 153a and 153b may not be rotationally offset 180 degrees relative to the first pair of openings 153a and 153b such that the respective axes intersect.
[0055] The configuration of first suture openings 153a and second suture openings 153b proximally and distally of first porous ring 153a may also be applied to other suture rings, such as rings 156b-d, disposed along spacer body 155. However, as shown in Figures 2I and 2J, the suture openings 153 associated with each of rings 156a-156d of spacer body 155 may be rotationally offset relative to the suture openings 153 of the other rings proximally and distally thereto. For example, the third suture opening 153c and the fourth suture opening 153d associated with the second suture ring 156b are rotated 90 degrees relative to the first suture opening 153a and the second suture opening 153b such that the axes A5 and A6 of the third suture opening 153c and the fourth suture opening 153d, respectively, are oriented perpendicular to the axes A3 and A4 of the first suture opening 153a and the second suture opening 153b. Such an offset arrangement can provide the surgeon with maximum flexibility for soft tissue attachment. However, it should be understood that in other embodiments, the third suture opening 153c and the fourth suture opening 153d do not need to be rotationally offset relative to the first suture opening 153a and the second suture opening 153b such that the axes A5 and A6 can be parallel to the axes A3 and A4.
[0056] Additionally, the bore 151 may extend axially through the entire spacer 150, including the tapered struts 152. Such a bore 151 may have a first portion 151a and a second portion 151b, as shown in FIG. 2N. FIG. 2N is a cross-sectional view of the humeral prosthesis 100 having other spacers (i.e., spacers 150a and 150c) with the same bore characteristics. The first portion 151a of the bore 151 may be located at the proximal end of the spacer 150 and may be conically tapered to accommodate, for example, the tapered struts 152 of another spacer 150 or the tapered struts 119 of the proximal body 110. The second portion 151b may be substantially cylindrical and may extend from the first portion 151a toward the distal end of the spacer 150 and extend through the struts 152. This allows a tool to traverse the spacer 150.
[0057] As with other components described herein, although a single implant spacer 150 is shown in FIGS. 2I and 2J, it should be understood that multiple implant spacers 150 of the same height or different heights can be included in the kit. For example, FIG. 2K illustrates multiple implant spacers 150 of different heights that can be included in the kit, such as a first implant spacer 150a, a second implant spacer 150b, a third implant spacer 150c, and a fourth implant spacer 150d. Each of these spacers 150a-150d can have the same characteristics as described above for the implant spacer 150, except that the height of the spacer body is different. For example, if four implant spacers 150a-150d are included in the kit, such implant spacers 150a-150d can have heights of 20 mm, 30 mm, 60 mm, and 100 mm, respectively, to accommodate various clinical situations in the operating room. Additionally, due to at least the height differences between implant spacers 150a-150d, the shorter spacers may have fewer suture openings 153 and porous rings 156 than the longer spacers, as shown in FIG. 2K.
[0058] 2L-2N show the assembly of a humeral prosthesis 100. In the particular embodiment shown, the humeral prosthesis 100 includes a proximal body 110, a stem component 130, and a first spacer 150a and a third spacer 150c of the kit described above. Thus, the humeral prosthesis 100 of FIGS. 2L-2N illustrates that two or more spacers 150 can be utilized to provide the humeral prosthesis 100 with a desired height. The humeral prosthesis 100 and its height can be assembled by stacking each component on top of the next. As shown, the third spacer 150c can be connected to the adaptor 140 of the stem component 130 by inserting the tapered post 142 into the tapered bore. Similarly, the first implant spacer 150a can be connected to the third implant spacer 150c by inserting the tapered struts 152 of the first implant spacer 150a into the first portion 151a of the bore 151 of the third implant spacer 150c. Finally, the proximal body 110 can be connected to the first implant spacer 150a by inserting the tapered struts 152 of the proximal body 110 into the first portion 151a of the bore 151 of the first implant spacer 150a. Each of these connections forms a series of Morse taper locks that secure each component to the next. Also, as shown in the cross-sectional view of FIG. 2N, the bore 122 of the proximal body 110 and the bores 151 of the implant spacers 151a, 150c, respectively, are aligned to form a bore that extends the entire height of the humeral prosthesis 100 to the stem component 130. This allows a driver to extend distally through the stack to the stem component 130 to drive a screw into the threaded opening 143 of the stem component 130 to provide additional fixation between the stem component 130 and the third implant spacer 150c, for example.
[0059] When assembled, the through bore 151b of each spacer 150a, 150c and the second bore 122 of the proximal body 110 align to cooperate to form a through bore extending entirely through the proximal body 110 and the spacers 150a, 150c. This allows, for example, a driver having a screw to be inserted through the proximal body 110 and the spacers 150a, 150c to the stem component 130. The screw can engage the threaded opening 143 in the adapter 140 of the stem component 130 and the distal-most spacer 150c to further secure the distal-most spacer 150c to the implant stem component 130.
[0060] Once the humeral prosthesis 100 has been assembled and implanted, it may be desirable to trial a particular constructed configuration to confirm that the desired articulation is achieved prior to finalizing the structure of the prosthesis 100 by attaching articulation components such as component 260 thereto.
[0061] 3A and 3B show a proximal body trial adaptor 200 that can be mounted with the proximal body 110 to facilitate trialing of the joint component in conjunction with the humeral prosthesis 100. The proximal body trial adaptor 200 can include a post 202, a flange 201 extending radially outward from the post 202, and a connecting portion 205 extending distally from the post 202. The post 202 can include an inclined surface 204 and a circumferentially extending groove 203. The connecting portion 205 can include a plurality of movable legs or bends 207. For example, the adaptor 200 can include three legs 207 that can be arranged in an evenly spaced arrangement around the longitudinal axis of the adaptor 200. However, in other examples, more or fewer legs 207 can be included. As shown in FIG. 3C, the connecting portion 205 and the post 202 can be inserted into the second bore 122 of the proximal body 110. Once inserted, the legs 207 may be forced radially inward by the surfaces defining the second bore 122, which may have a diameter less than the maximum diameter defined by the legs 207 in a relaxed, unflexed state. In this regard, the legs 207 may be forced from within the bore 122 against the proximal body 110 to secure the adaptor 200 therein. In this configuration, the angled surface 204 of the post 202 may be flush with or recessed relative to the angled first proximal surface 115 of the proximal body 1110 to provide clearance for the trial joint component. Once trialing is complete, the proximal body trial adaptor 200 may be removed by grasping the post 202 and pulling the trial adaptor 200 out of the second bore 122. This may be aided by the grooves 203 forming a finger pulling mechanism.
[0062] The flange or tab 201 extends radially from the post 202 and at an angled distally away from the post 202. This angled distal extension allows the flange 201 to extend over the first bore 121 when the adapter 200 is inserted into the second bore 122, as best seen in FIG. 3C. The flange 201 may include an opening 208 extending through its entire thickness. The opening 208 may be a scalloped opening or a splined opening. In this regard, a plurality of scallops or splines 206 may be arranged around the opening at predetermined increments that may be defined by an angle α, as shown in FIG. 3B. In other words, each scallop 206 may be rotationally offset from an adjacent scallop by an angle α measured from a center point of the opening 208. The incremental angle α may be, for example, 30 degrees, but may also be between 5 degrees and 45 degrees. As discussed below, such scallops 206 allow an articulating component received within the opening 208 to be rotated at regular intervals to create a desired eccentricity relative to the proximal body 110 and particularly the first bore 121. In the particular embodiment shown, seven scallops 206 are provided. However, more or fewer scallops 208 are contemplated, such as, for example, between three and twelve scallops.
[0063] 4A-5G show an exemplary first trial joint component including a reverse type trial insert 210 and a trial tray 220. Thus, the trial joint component is a reverse type trial joint component. FIGS. 4A and 4B show an exemplary reverse type trial insert 210, which may include an articular side 211 and a connecting side 212. The articular side 211 may include a concave articular surface 213 that may be configured to articulate with a trial glenosphere (not shown). The connecting side 212 may be configured to connect to a trial tray 220. In this regard, the connecting side 212 may include a pair of legs or flexures 214 that may be configured to fit within an opening or recess in the trial tray 220, such as recess 227, which will be described further below. However, other connection mechanisms are also contemplated, such as, for example, a snap-fit mechanism or a twist-lock mechanism.
[0064] 5A-5G show an exemplary trial tray 220. The trial tray 220 can include a tray body or trial body 221 and a boss 222 extending distally from the tray body 221. The tray body 221 can include a circumferentially extending rim 223 and an inner surface 225 bounded by the rim 223, the rim 223 and the inner surface 225 cooperating to define a cavity for receiving at least a portion of the connecting side 212 of the reverse type trial insert 210. A central opening or recess 227 can extend at least partially into the tray body 221 and through the inner surface 225 such that a central axis CA2 of the opening 227 is coaxial with a central axis of the trial tray body. A through bore 229 extends through the tray body 221 and overlaps with the opening 227 such that a central axis CA1 of the through bore 229 is offset from a central axis CA2 of the opening 227 by a distance D1, as shown in FIG. 5A. The tray body 221 may also include a flat distal surface 228 disposed opposite the inner surface 225 .
[0065] The boss 222 extends distally from the distal face 228. The through bore 229 extends through the boss 222 such that the central axis of the boss 222 is also the central axis of the through bore 229. In other words, the central axis CA1 is the central axis of the through bore 229 and the boss 222. The through bore 229 can have threads 226 along at least a portion of its length, as best shown in FIG. 5C. The boss 222 can also include teeth or protrusions 224 extending radially outward therefrom. Such teeth 224 can be configured to be received and engaged with any one of the scallops 206 of the proximal body trial adaptor 200 when the boss 222 is received within its scallop opening 208, as best shown in FIG. 5D. The teeth 224 may be stationary teeth such that the boss 222 may be required to be removed from the scallop opening 208 and out of engagement with one scallop 206 in order to engage another scallop 206. However, in other embodiments, the teeth 224 may be movable radially inward such that a threshold amount of torque may be applied to the tray 220 when the boss 222 is positioned within the scallop opening 208 to move the teeth 224 inward and rotate the tray 220 to another clocked position within the opening 208 where the teeth 224 snap back into place to engage another scallop 206. In either embodiment, the engagement of the teeth with the scallops generally inhibits rotation of the trial tray 220 relative to the adapter 200 such that the boss 222 is rotationally fixed within the scallop opening 208.
[0066] As shown in FIGS. 5E-5G, the trial tray 220 can have multiple eccentric configurations with respect to the implant proximal body 110. Such eccentric configurations can be determined, at least in part, by which scallop 206 the tooth 224 engages. For example, FIGS. 5D and 5E show a first eccentric configuration in which the tooth 224 engages the first scallop 206a. In this first eccentric configuration, an axis A7 extending through the tooth 224 and the first scallop 206a is coplanar with a midline plane MP that bisects the proximal body 110 and extends in the SI direction and substantially in the ML direction. Thus, in this configuration, the central axes CA1, CA2 of the through bore 229 and central opening 227 are coplanar with the midline plane MP such that the trial tray 220 does not exhibit eccentricity with respect to the proximal body 110.
[0067] This is in contrast to the second eccentric arrangement as shown in FIG. 5F, in which the trial tray 220 is rotated by an angle α from the first configuration described above, such that the tooth 224 engages the second scallop 206b adjacent to the first scallop 206a. Thus, in this second eccentric arrangement, the axis A7, now extending through the tooth 224 and the second scallop 206b, intersects the midline plane MP by an angle α. In addition, the central axis CA1 of the through bore 229 is coplanar with the midline plane MP, whereas the central axis CA2 of the central opening 227 is not. In this way, the central axis CA2 of the central bore is offset from the midline plane in the AP direction, resulting in an eccentric relationship between the trial tray 220 and the proximal body 110. This leads to an eccentric positioning of the articular surface 221 of the trial insert 210 when coupled to the trial tray 220.
[0068] 5G shows a third eccentric position illustrating increased eccentricity relative to the first and second eccentric configurations described above. As shown, the tooth 224 is rotated within the scallop opening 208 to engage the third scallop 206c adjacent to the second scallop 206c. In this regard, an axis A7 intersecting the third scallop 206c and the tooth 224 intersects the midline plane at an angle 2α. In this position, the central axis CA2 of the central opening 227 is offset from the midline plane MP in the AP direction further than in the second eccentric configuration. It should be noted that eccentricity may be greatest when the axis A7 is perpendicular to the midline plane MP.
[0069] 6 illustrates an exemplary humeral head trial 230 according to one embodiment of the present disclosure that may be implemented with the humeral prosthesis 100. The humeral head trial 230 may include an articular side 231 and a connecting side 232. The articular side 231 may include a convex articular surface 233, which may be partially spherical and configured to articulate with a corresponding concave glenoid prosthesis or trial component. The connecting side 232 may be configured to individually connect to a humeral head coupler trial, such as the humeral head coupler trial 250, described in further detail below. In this regard, the connecting side 233 may include a socket 234 and a tab or rib 236 extending radially inward into the socket 234, as shown in FIG. 6B.
[0070] The humeral head trial 230 also represents a humeral head prosthesis that may be configured to mate with a humeral head coupler, such as the humeral head coupler 240 shown in FIG. 7. The humeral head coupler 240 may include a connector 243, a plate or flange 241, and a tapered post 242. The tapered post 242 may be configured to be received within the second bore 122 of the proximal body 110. In addition, the connector 240 may be configured to connect to the connection side 232 of the humeral head 230. For example, the connector 240 may be a circular boss configured to be received within the socket 234 of the humeral head 230.
[0071] 8A and 8B illustrate an exemplary humeral head coupler trial 250 according to one embodiment of the present disclosure. The coupler trial 250 may include a connection body 251 and a boss 252 extending from the connection body 251. The connection body or trial body 251 may be configured to engage the connection side 232 of the humeral head trial 230 to secure the humeral head trial 230 thereto. For example, the socket 234 on the connection side 232 of the humeral head trial 230 may have a corresponding size and shape to receive the trial body 251 therein. The trial body 251 may include a through bore 255 and an axial slot 253. The axial slot 253 may extend into a side of the trial body 251 and may extend from a first or upper surface 256 to a second or lower surface 258. The axial slot 253 may be configured to receive a feature, such as a tab 236 in the connection side 232 of the humeral head trial 230, to prevent rotation relative thereto. The through bore 255 may define a central axis CA3 that is offset from the central axis CA4 of the axial slot 253 by a distance D2, which may correspond to a degree of offset applied to the humeral head trial 230 when coupled to the coupler trial 250. For example, the coupler trial 250 may have an offset of 3.5 mm. However, other offsets are possible, such as, for example, an offset of 1.5 mm or a centered offset (i.e., no offset). Thus, a kit may include multiple coupler trials 250, each having a different offset. In addition, the trial body defines a central axis CA5 that extends through a center point of the trial body. The central axis CA5 is offset from the central axis CA3 of the through bore by a distance D3.
[0072] The boss 252 may be similar to the boss 222 of the trial tray 220. In this regard, the boss 252 may have teeth or protrusions 254 that may be configured to engage any of the scallops 206 on the proximal body trial adaptor 200 to position the humeral head coupler trial 250 and the associated humeral head trial 230 in any one of a number of eccentric arrangements, such as those described above. Also similar to the trial tray 220, a through bore 255 extends through the boss 252 such that a central axis CA3 of the through bore 255 is coaxial with the boss 252. As shown in FIGS. 8A and 8B, the coupler trial 250 may be secured to the implant proximal body 110 or another device, such as the trial proximal body 230 described below, via a screw 257 positioned within the through bore 255.
[0073] As explained above, the humeral prosthesis 100 can be adapted to provide a trial function, but typically it is desirable to first implant a "trial" component that exhibits the function of the humeral prosthesis 100. In this regard, a trial humeral prosthesis can be constructed and implanted within the humeral shaft. With the trial prosthesis in place, the range of motion, joint positioning, and other parameters that may predict success can be tested or otherwise determined. If the surgeon determines that a particular trial implant exhibits the desired surgical outcome, the actual humeral prosthesis 100 can be implanted in a configuration that is intended to match the successful trial configuration, such that the final permanent implant will have the desired parameters that were tested or identified in the corresponding trial configuration.
[0074] 9A illustrates an exemplary humeral trial prosthesis 300 implanted within the humeral shaft 52, according to one embodiment of the present disclosure. The humeral trial prosthesis 300 can include a trial proximal body 310, an expandable trial stem component 330, and one or more trial spacers 350 positioned between the trial proximal body 310 and the expandable stem component 330 to account for the length of bone removed.
[0075] 9B-9D show an exemplary trial proximal body or trial prosthesis body 310 according to one embodiment of the present disclosure. The trial proximal body 310 corresponds to the implant proximal body 110. As such, the trial proximal body 310 has similar features as those of the implant proximal body 110. For ease of review, similar elements of the trial proximal body 310 are given similar reference numerals as those of the implant proximal body 110, but within the range of 300 numerals. For example, the trial proximal body 310 can have a similar geometric profile as that of the implant proximal body 110, such as having an outer surface 311, an inner surface 314, a first AP surface 313a, a second AP surface 313b, a first proximal surface 315, a second proximal surface 316, and a distal surface 318. Additionally, the trial proximal body can also have a second bore 322 bounded by a notch 320 and a first bore 321 that intersects with the second bore 322. The first bore 321 and the second bore 322 are disposed within the trial proximal body in a manner similar to that of the implant proximal body 110.
[0076] However, the trial proximal body 310 differs from the implant proximal body 110 in that the first bore 321 may be a scalloped bore having a threaded opening 325 disposed therein, rather than a smooth bore like that of the first bore 121 of the implant proximal body 110. In this regard, the scalloped bore 321 may include a scallop 326 formed within the trial proximal body 310 itself, similar to the scalloped opening 208 of the proximal body trial adaptor 200. In this regard, the first bore 321 may have a plurality of scallops or splines 326 arranged about a central axis of the first bore 321. For example, the first bore 321 may have twelve scallops 326 as shown in FIG. 9D. In another example, the first bore 321 may have seven scallops 326 like that of the proximal body trial adaptor 200 shown in FIG. 3A. In further examples, the first bore 321 can have more or fewer scallops 326, such as, for example, between 3 and 12 scallops. Additionally, the scallops 326 can be rotationally offset from one another by the same incremental angle α as described above. Thus, the first bore 321 can be configured to clock a trial joint component, such as the trial tray 220 or humeral head coupler trial 250, in various eccentric arrangements.
[0077] It should be understood that while the joint trial components, such as the insert 210, tray 220, insert 230, and coupler trial 250, are described above in connection with their use in connection with the implant proximal body 110, their use is equally applicable to the trial proximal body 310. However, because the trial proximal body 310 has a scalloped opening 321 formed therein, the proximal body trial adaptor 200 may not be utilized with the trial proximal body 310.
[0078] Another difference between the trial proximal body 310 and the implant proximal body 110 is that instead of a porous patch 117, the trial proximal body 310 may include a visualization pocket 317. As shown in Figures 9B and 9C, the pocket 317 may be formed in the trial proximal body 310 in the same shape and in the same location as the porous patch 317 on the implant proximal body 110. Thus, during trialing, the surgeon can visualize where the porous patch 117 will be located relative to anatomical structures such as soft tissue to aid in determining the viability of a particular humeral trial prosthesis 300 for implementation in the final humeral prosthesis 100.
[0079] A further difference between the trial proximal body 310 and the implant proximal body 110 is in its connection mechanism. As previously described, the implant proximal body 110 may include tapered posts 119 that taper lock with another structure, such as the implant spacer 150 or the implant stem component 130. However, such connection mechanisms are generally preferred for permanent or semi-permanent connections best suited for a final implant, such as the implant proximal body 110. On the other hand, the trial proximal body 310 may be a temporary structure that is desirably quickly assembled and disassembled during a surgical procedure. In this regard, the trial proximal body 310 may instead include a quick connect / disconnect mechanism for connection to other components of the humeral trial prosthesis. An exemplary quick connect / disconnect mechanism is shown in FIG. 9B and may include a pair of outer legs 327 and a pair of inner legs 329.
[0080] The inner leg or inner bend 329 is disposed adjacent the outer leg or outer bend 327 and may include an inwardly extending protrusion 329a. The outer leg 327 may be parallel to the inner leg 329 and may be offset from the outer leg by a gap. The outer leg 327 is generally stiffer than the inner leg 329 and therefore generally resists movement more than the inner leg 329 configured to move outwardly from a first position to a second position. The inner leg 329 is biased toward the first position. The outer leg 327 thus acts as a limiter or stop for the inner leg 329 to prevent the inner leg 329 from moving too far and potentially being damaged or permanently deformed. Thus, the outermost position that the inner leg 329 can be is where the inner leg 329 abuts the outer leg 327. The gap between the outer leg 327 and the inner leg 329 can present some difficulty in cleaning and sterilization as debris can become trapped in the gap. To help mitigate such difficulties, each outer leg 327 can include a cleaning slot 328 that extends through the outer leg 327 and communicates with the gap. This can make it easier to flush or otherwise remove debris from the gap not only during post-operative cleaning and sterilization, but also during procedures to ensure that the inner leg 329 has freedom of movement.
[0081] FIG. 9E illustrates an exemplary trial proximal body 310' according to another embodiment of the present disclosure. The trial proximal body 310' is similar to the trial proximal body 310 in that it includes a first bore 321 and a second bore 322. In addition, the first bore 321 can be a scalloped bore as previously described. However, the trial proximal body 310' differs in that it is an implantable trial. In other words, in some procedures, such as primary or revision shoulder arthroplasties, where sufficient bone stock exists, the proximal humerus 53 may not need to be removed, and instead, the proximal humerus 53 may be prepared or otherwise shaped to accommodate a prosthesis that is inserted into the bone such that the bone of the proximal humerus 53 surrounds the proximal body 310'. The trial proximal body 310' can be utilized in such procedures and is thus configured to be inserted into a void or cavity within the proximal end of the humerus 50. As such, its geometric profile is generally narrower than that of the trial proximal body 310 to fit within the bone cavity. In addition, the proximal body 310' can have a cleaning window 328' extending therein that can facilitate cleaning and sterilization after each procedure.
[0082] 9F-9H show an exemplary trial spacer 350. The trial spacer 350 can share common features with the implant stem component 130 and particularly the adaptor 140. For example, the trial spacer 350 can include a body 354, a recess 358, and a proximal collar or shoulder 359. In this regard, the recess 358 is bounded proximally by the shoulder 359 and distally by the body 354. This allows features such as the inner leg 329 of the trial proximal body 310 to securely engage the trial spacer 350. However, unlike the adaptor 140, the trial spacer 350 can include a post 356 extending proximally from the body 354. The post 356 is preferably cylindrical except for two flats 356a and 356b extending axially along the post 356, which are preferably parallel to one another. This configuration can prevent rotation of a component sliding on the posts 356 and can limit the possible rotational orientation of other components relative to the posts 356, which can aid in aligning different features between different components.
[0083] Additionally, the bore 351 can extend axially through the entire spacer 350, including the post 356. Such a bore 351 can have a first portion 351a and a second portion 351b, as shown in FIG. 9J, which is a cross-sectional view of another spacer having the same bore features. The first portion 351a of the bore 351 can be located at the distal end of the spacer 350 and can include opposing flats 357a and 357b, as shown in FIG. 9H, for engaging with the post 356 and its corresponding flats 356a and 356b of another spacer 350 or another component, such as, for example, the taper protection insert 370 and the expandable trial stem component 330, each of which is described in further detail below. The second portion 351b can be substantially cylindrical and can be located toward the proximal end of the spacer 350, extending through the post 356. This allows a tool to traverse the length of the spacer 350.
[0084] The trial spacer 350 can also share common features with the trial proximal body 310. More specifically, the trial spacer 350 can include an inner leg 352 having an inwardly extending protrusion 352a, an outer leg 353, and a cleaning slot 355 similar to those of the trial proximal body 310, allowing the trial spacer 350 to be connected to other trial spacers 350 and to an expandable trial stem 330 (discussed below) or an implant stem component 130 (discussed above), as previously described with respect to the trial proximal body 310.
[0085] As with other components described herein, although a single trial spacer 350 is shown in Figures 9F-9H, it should be understood that multiple trial spacers 350 of the same height or different heights can be included in the kit. For example, Figure 9I shows multiple trial spacers of different heights, such as a first spacer 350a, a second spacer 350b, a third spacer 350c, and a fourth spacer 350d, that can be included in the kit. Each of these spacers 350a-350d can have the same characteristics as described above with respect to the trial spacer 350, except that the height of the spacer body is different. For example, if four trial spacers 350a-350d are included in the kit, such trial spacers can have heights of 20 mm, 30 mm, 60 mm, and 100 mm, respectively, to accommodate various clinical situations in the operating room.
[0086] The trial spacers may be "push-to-connect." For example, as shown in FIG. 9J, when connecting trial spacer 350b to trial spacer 350c, trial spacer 350b may be positioned adjacent to post 356 of spacer 350c with flats 357a and 357b of first portion 351a of bore 351 aligned with flats 356a and 356b of post 356. With this configuration, there are only two possible rotational orientations in which trial spacer 350b may be coupled to trial spacer 350c. In either rotational configuration, as trial spacer 350b advances distally, each inner leg 352 is aligned with a respective recess 358 of spacer 350c. When the trial spacer 350b is fully advanced, it is positioned relative to the trial spacer 350c such that the inner leg 352, and in particular the inwardly extending protrusion 352a, fits within the recess 358 of the spacer 350c. The inner leg 352 and its inwardly extending protrusion 352a are shaped and positioned such that when the trial spacer 350b is connected to the trial spacer 350c, the shoulder 359 of the trial spacer 350c first flexes the inner leg 352 outward. The inner leg 352 can then "snap" back into place once the inwardly extending protrusion 352a clears the shoulder 359. This snap fit can provide audible and / or tactile feedback to confirm the connection. The inner leg may provide some resistance to trial spacer 350b being pulled proximally to separate it from trial spacer 350c, but because trial spacers 350b and 350c are typically under compression during trialing, there is no significant concern that trial spacer 350b will unintentionally separate from trial spacer 350c during use. To separate trial spacer 350b from trial spacer 350c, it is simply pulled proximally away from trial spacer 350c.Furthermore, as will be appreciated from the above discussion, the engagement between flats 356a and 356b of 356 and flats 357a and 357b of the internal cavity of trial spacer 350b prevents rotation between the two components once connected.
[0087] 10A and 10B illustrate an exemplary expandable trial stem 330 according to one embodiment of the present disclosure. The expandable trial stem 330 may include a stem 332, an adaptor 340, and an expansion bolt 335. The stem 332 is configured to be inserted into the intramedullary canal of the remaining humeral shaft 52. However, unlike the stem 132 of the implant stem component 130, which impacts the bone in a press-fit manner, the stem 332 may be inserted into the humeral shaft 52 without impaction and then expanded to securely engage the bone. This may help preserve the shape of the bone and the intramedullary canal for subsequent implantation of the implant stem component 130.
[0088] The stem 332 can include a proximal portion 334 and a distal portion 336 split along its length to form first and second movable stem portions 337a, 337b extending from and cantilevered relative to the proximal portion 334. An expansion bolt or driver 335 can extend through the proximal portion 334 and can be movable in a proximal-distal direction between the first and second movable stem portions 337a, 337b such that distal movement of the expansion bolt 335 causes the first and second stem portions 337a, 337b to move radially outwardly away from one another and proximal movement of the expansion bolt 335 causes the first and second stem portions 337a, 337b to move radially inwardly toward one another under their own bias. Thus, the first and second stem portions 337a, 337b are biased to a first or contracted configuration and are movable to a second or expanded configuration. While in the first configuration, the stem 332 is positioned within a bore in the humerus 50 and may be freely rotated therein. While in the second configuration, the first and second stem portions 337a, 337b are pressed against the bone and secured thereto until trialing is completed. Once trialing is completed, the first and second stem portions 337a, 337b may be moved back to the first configuration for removal by moving the expansion bolt 335 proximally. This helps prevent damage and / or alteration to the bone prior to insertion of the implant stem component 130. Further details of these operations as well as other exemplary stem and expansion bolt constructions are described in U.S. Pat. No. 9,011,549, the disclosure of which is incorporated herein by reference in its entirety.
[0089] The adaptor 340 is similar to the adaptor 140 of the implant stem component 130. For ease of review, similar features have been given similar reference numerals as those of the adaptor 140. For example, the adaptor 340 may include a proximal collar or shoulder 341, a distal collar 342, a distal face 344, an adaptor body 345, a recess 346, a protrusion 347, and a flat 349. However, unlike the adaptor 140, the adaptor 340 may include a post 348 extending proximally from the adaptor body 345. The post 348 is preferably cylindrical except for two flats 348a and 348b that extend axially along the post 348, and the flats 348a and 348b are preferably parallel to one another. This configuration can prevent rotation of components sliding on the posts 348 and can also limit possible rotational orientations of other components relative to the posts 348 to aid in aligning different features between different components. The posts 348 can be configured to connect to one of the trial spacer 350 and / or the trial proximal body 310. Additionally, a bore (not shown) can extend axially through the entire adapter 340 including the posts 348. The expansion bolt 335 can be accessed through such bore.
[0090] In some embodiments, the expandable trial stem 330 may not be used in the trial humeral prosthesis. Instead, the implant stem component 130 may be inserted into the humeral shaft and used with the trial spacer 350 and the trial proximal body 310 to trial the final implant configuration. As shown in FIG. 2H, the implant adaptor 140 may include a central bore 148 defined by a tapered inner surface, such that an implant spacer having a tapered post 152 (e.g., spacers 150a-d) may be secured to the adaptor 140 with a Morse taper fit. However, as shown in FIGS. 9F-9J, the trial spacers 350a-d may not include a post for engagement with the adaptor 140, and instead may be configured to engage the adaptor 140 of the expandable trial stem 330 340 and a non-tapered post 348 extending therefrom.
[0091] 11A illustrates an exemplary taper protection insert 370 according to one embodiment of the present disclosure. The taper protection insert or trial alignment peg 370 helps protect the tapered bore 148 of the implant stem component 130 during its insertion and can be used to further adapt the adapter 140 for connection with the trial spacer 350 or proximal body 310. The taper protection insert 370 generally includes a post 378 and a connecting portion 372. The post or non-tapered portion 378 is similar to the post 348 of the expandable trial stem 330 in that it is generally cylindrical and includes opposing flats 378a and 378b. The connecting portion or non-tapered portion 372 extends from the post 378 and can include multiple bends 374a-374c, such as two to four bends, that cooperate to taper inwardly in a proximal-to-distal direction to define an outer diameter having a maximum diameter greater than the inner diameter of the tapered bore 148 of the adaptor 148. Thus, when the connecting portion 372 is inserted into the tapered bore 148 of the implant stem component 130, the narrower bore 148 pushes the bends 347a-347c inwardly, which correspondingly pushes the tapered bore 148 outwardly, thereby securing the taper protector 370 to the adaptor 140 of the implant stem component 130. However, other embodiments of the insert 370 may not include matching bends 374a-374c, but rather may have a rigid connecting portion 372 that is tapered and / or has a separate connecting mechanism, such as a snap-fit mechanism, for connection to the stem component 130.
[0092] 11B, the taper protector insert 370 can be inserted into the tapered bore 148 of the implant adaptor 140 prior to coupling the trial spacer 350 or an impaction tool, such as an inserter / extractor handle 700, discussed further below, to the implant stem 110. Thus, the tapered portion 372 of the taper protector 370 can be received within the corresponding, but smaller, tapered bore 148 of the implant stem component 130 such that the upper, non-tapered portion 372 of the taper protector 370 extends proximally therefrom. With this configuration, when the trial spacer 350 is connected to the adaptor 140, its inner leg 352 engages the recess 146 of the adaptor 140 and the post 372 of the taper protector 370 is received within the corresponding bore 351 a in the spacer, helping to stabilize and secure the spacer 350 on the adaptor 140. Also, in this configuration, a pushing tool, such as the inserter / extractor handle 700, can be separately connected to the adapter 140 with the taper protector 370 inserted therein. The taper protector 370 can help ensure that there is not a large gap space between the pushing tool and the implant adapter 140, thereby helping to ensure that the pushing force is evenly distributed and that the pushing tool does not damage the implant adapter 140 and the tapered bore 148 therein.
[0093] Various instruments may be provided to assist in preparing the humeral shaft 52 for receipt of the prosthesis 100, 300 described above. Such instruments may include one or more of a bone clamp assembly 400, a sounder 500, a reamer planer 600, an inserter / extractor handle 700, a height gauge 800, a pusher stand 900, and a taper separation tool 1000.
[0094] 12A-12E illustrate an exemplary bone clamp assembly 400 according to one embodiment of the present disclosure. The bone clamp assembly 400 can include a bone clamp 402 and a resection guide 420.
[0095] The bone clamp 402 may include a first member 401a and a second member 401b pivotally connected to the first member 401a. Such connection may be configured via a pin 414 that may define a pivot axis about which the first member 401a and the second member 401b pivot relative to one another. The first member 401a may include a first handle 410a and a first jaw 411a, and the second member 401b may include a second handle 410b and a second jaw 411b. The first member 401a and the second member 401b cross each other at a location between the jaws 411a, 411b and the handles 410a, 410b. The pivotable connection can be configured in this position such that moving the handles 401a and 410b together moves the jaws 411a and 411b together and moving the handles 410a and 410b apart moves the jaws 411a and 411b apart. However, other configurations are contemplated where the handles 410a and 410b do not overlap and moving the handles 410a and 410b apart moves the jaws 411a and 411b together and moving the handles 410a and 410b apart moves the jaws 411a and 411b together.
[0096] As shown in FIGS. 12A and 12B, the jaw axis A9 extends along the length of the jaws 411a and 411b and is equidistant between the jaws 411a and 411b, and the handle axis A10 extends along the length of the handles 410a and 410b and is equidistant between the handles 410a and 410b. Such axis A9 and axis A10 may intersect each other at an angle β, as shown in FIG. 12B. This angle β may be an obtuse angle, for example, 130 degrees. In other embodiments, the angle β may be between 120 degrees and 140 degrees. This angular configuration between the handles 410a, 410b and the jaws 411a, 411b helps provide clearance for the bone saw to access the resection guide 420 and for positioning of soft tissue when the jaws 411a and 411b are clamped to the humerus shaft 52.
[0097] The bone clamp 402 may also include a handle locking mechanism 450. The handle locking mechanism 450 may include a threaded shaft 454 extending from one of the first and second handles 410a, 410b and through the other of the first and second handles 410a, 410b. Additionally, the knob 452 may be threadedly coupled to the threaded shaft 454 and may be positioned outside of the handles 410a, 410b through which the threaded shaft 454 extends. For example, as shown in FIG. 12A, the threaded shaft 454 extends from the second handle 410b and through the first handle 410a. The knob 452 is threadedly coupled to the threaded shaft 454 and positioned outside the first handle 410a such that rotation of the knob 452 in a first direction prohibits the first and second handles 410a, 410b from moving away from one another, effectively locking the jaws 411a, 411b in clamping engagement with the bone. Conversely, rotation of the knob 452 in a second direction permits the handles 410a, 410b to move away from one another, thereby allowing the jaws 411a, 411b to disengage from the bone. In either the right- or left-handed configuration of the clamp 402, the knob 540 and the threaded shaft 454 can be disposed in opposing directions. Other handle locking mechanisms are contemplated, such as a ratchet mechanism.
[0098] As shown in FIG. 12G, the first jaw 411a may be referred to as a posterior jaw because it may be positioned along the posterior aspect of the humerus shaft 52 when clamped to the humerus shaft 52, and the second jaw 411b may be referred to as an anterior jaw because it may be positioned along the anterior aspect of the humerus shaft 52 when clamped to the humerus shaft 52. The first jaw 411a and the second jaw 411b may each have a first row of teeth 415 that may help prevent slippage of the jaws 411a and 411b when engaged with bone. However, in other embodiments, the second jaw 411b may have a first row of teeth 415a and a second row of teeth 415b, as shown in FIG. 12H, which may facilitate vertical positioning for accurate vertical resection, as described further below.
[0099] The second jaw 411b can be configured to connect to the resection guide 420. In this regard, the second jaw 411b can include a first hole 413a and a second hole 413b extending through a top surface thereof. Additionally, the transverse opening 417 can extend through a free end of the second jaw 411b and into the second jaw 411b in a direction transverse to the first hole 413a and the second hole 413b such that the transverse opening intersects with the second hole 413b. The second jaw 411b can also include a plunger 430, a spring 435, and a pin 437. The plunger 430 can include a first slot 434 that can extend through the plunger in the SI direction. The plunger 430 may also include a second or captured slot 432 that is longitudinally offset from the elongated slot 434 and extends in a front-to-back direction into a side of the plunger 430. As best shown in FIG. 12D, a protrusion 436 may extend inwardly into the second slot 432 and longitudinally into an opening that defines an entrance to the second slot 432, and a cam surface 438 may be formed on the protrusion 436 adjacent the second slot 432. When assembled, the plunger 430 and spring 435 may be positioned within the transverse opening 417 such that the spring 435 biases the plunger 430 outwardly toward the free end of the second jaw 411b. The plunger 430 may be movably connected to the second jaw 411b via a pin 437 and the first slot 434. In this regard, when the plunger 430 is received within the transverse opening 417, the first slot 434 aligns with the second hole 413b in the second jaw 411b and the pin 437 extends through the second hole 413b to engage the first slot 434. This allows the plunger 430 to slide back and forth within the transverse opening 417 from a first position to a second position while remaining fixed within the transverse opening 417. Thus, the plunger 430 can be biased to the first position and can be pushed to move the plunger to the second position against the bias of the spring 435.
[0100] The second jaw 411b may also have a drop rod protrusion extending from its exterior or front side. Such drop rod protrusion 419 extends outwardly and forwardly therefrom. The drop rod protrusion 419 may have a rod slot 418 and / or one or more holes extending therethrough such that a drop rod, such as the drop rod 440 shown in FIG. 12A, may be disposed therethrough to align the jaws 411a and 411b with respect to the diaphyseal axis of the humerus diaphysis 52.
[0101] The resection guide 420 may be modular such that it may be connected to the bone clamp assembly 400, and in the particular embodiment shown, to the second jaw 411b. The resection guide 420 may include a first surface, or upper surface 421, and a second surface, or lower surface 422. The upper surface 421 may be flat and may form an uncaptured resection guide surface. The resection guide 420 may also include a resection guide slot 424 that is fully enclosed to form a captured resection guide slot. Such resection guide slot 424 may be located between the upper surface 421 and the lower surface 422, and may be a predetermined distance from the upper surface 421. This allows the surgeon to resect along the upper resection surface 421 and then, if necessary, resect through the resection guide slot 424 to remove a known amount of bone relative to the amount of initial resection. For example, an additional 2 mm of bone may be removed by cutting through the resection guide slot 424. This configuration allows the surgeon to know how much bone remains above the first and second jaws 411 a and 411 b after resection because it may be desirable to have a known amount of bone above the jaws 411 a and 411 b for additional operations subsequent to the resection, such as, for example, a reaming operation. In this regard, for example, resectioning along the top surface 421 may leave approximately 10 mm of bone above the first and second jaws 411 a and 411 b, while resectioning through the capture guide slots 424 may leave approximately 8 mm of bone above the first and second jaws 411 a and 411 b.
[0102] The resection guide 420 may also include a first strut 423a and a second strut 423b extending from the lower surface 422. The second strut 423b may have a recess or notch 425 extending therein transversely to a longitudinal axis of the strut 423b, as best shown in FIG. 12D. The first strut 423a is configured to be received within a first opening 413a in the second jaw 411b. As will be described in more detail below, the second strut 423b is configured to be received within a second slot 432 of the plunger 430, with a protrusion 436 of the plunger 430 configured to engage the notch 425.
[0103] 12D and 12E show the connection of the resection guide 420 to the second jaw 411b. As shown, the first post 423a can be inserted into the first opening 413a of the second jaw 411b, which defines an axis of rotation A11 about which the remainder of the resection guide 420 rotates or pivots to a final position. In this regard, the end of the resection guide 420 having the second post 423b can be rotated toward the plunger 430 protruding from the free end of the second jaw 411b such that the second slot 432 faces the second post 423b. When the second post 423b engages the plunger 430, the second post 423b contacts the cam surface 438, which urges the plunger 430 inward against the bias of the spring 435 to the second position. This allows the second post 423b to move further within the second slot 432. Once the second post 423b clears this cam surface 438 and is fully positioned within the second slot 432, the bias of the spring 435 returns the plunger 430 to the first position. As this occurs, the protrusion 438 engages the notch 425 in the second post 423b, preventing the second post 423b from returning along the same rotational path it just traveled. Thus, in this configuration, the resection guide 420 is inhibited from rotating back out of engagement with the plunger 430 unless the plunger 430 is forced back into the second position. Additionally, the engagement between the protrusion 426 and the notch 425 prevents the resection guide 420 from being lifted upwardly and away from the second jaw 411b. The connection with the second jaw 411b of the resection guide 420 can be formed before or after the bone clamp 402 is clamped to the bone.
[0104] The bone clamp assembly 400 may be versatile in that it may be used on both the left and right humerus. For example, the bone clamp assembly 400 as shown in FIG. 12A is configured for clamping the left humerus of a patient such that the first jaw 411a engages the posterior aspect of the left humerus and the second jaw 411b engages the anterior aspect of the left humerus and the handles 410a and 410b extend outwardly away from the patient's body. When used on the right humerus, the clamp 402 is flipped over so that the first jaw 411a and the second jaw 411b engage the posterior and anterior aspects of the right humerus, respectively, and the handles 410a and 410b extend outwardly away from the patient's body. The second jaw 411b may be configured to allow a resection guide 420 to be connected to either side thereof. In this regard, the first hole 413a can extend entirely through the jaw 411b such that the first post 423a of the resection guide 420 can engage the first hole 413a from either side of the second jaw 411b. In addition, the plunger is configured such that the second post 423b can engage the plunger from either side of the second jaw 411b.
[0105] When the bone clamp 402 is clamped to the humerus shaft 52 with the resection guide 420 connected to the second jaw 411b, the resection guide slot 424 is preferably aligned perpendicular to the shaft axis of the humerus shaft 52. Such perpendicularity can be aided by the arrangement of teeth 415 formed on the first jaw 411a and the second jaw 411b. In this regard, a typical humerus shaft can have a triangular cross-sectional shape. As discussed above, each jaw 411a and 411b can have one or more rows of teeth 415 that can assist in orienting the jaws 411a and 411b and the resection guide 420 to a desired vertical position. For example, the first jaw 411a can have a row of teeth 415 that can extend along an arcuate path, as shown in FIG. 12F. The second jaw 411b, on the other hand, can have a first row of teeth 415a and a parallel second row of teeth 415b, each of which can extend linearly in a generally "V" shaped pattern, as shown in FIG. 12H. In operation, the second jaw 411b can be disposed against the anterior surface of the humeral shaft 52, and the first jaw 411a can be positioned against the posterior aspect of the humeral shaft 52, as shown in FIG. 12G. The arcuate extensions of the teeth 415 of the first jaw 411a and the V-shaped extensions of the first row of teeth 415a and the second row of teeth 415b of the second jaw 411b interact with the triangular structure of the humeral shaft 52 to vertically align the jaws 411a and 411b if they are not already vertically aligned. Additionally, the additional second row of teeth 415b of the second jaw 411b can help prevent the clamp 402 from pivoting out of vertical alignment. In other words, the second row of teeth 415b helps inhibit the clamp 402 from pivoting as compared to a second jaw 411b having only the first row of teeth 415a. Vertical alignment can be confirmed by a drop rod 440 extending through a rod slot 418 in the second jaw 411b. Once properly aligned, a bone saw, such as the reciprocating saw 10 of FIG. 12G, can be passed through the captured slot 424 or along the non-captured upper guide surface 422 to resect the humerus shaft 52.Once the bone has been resected, the resection guide 420 may be removed by pushing the plunger 430 to release the second post 423b, swinging the second post 423b out of the second slot 432, and pulling the resection guide 420 up to remove the first post 423a from the first opening 413a. The clamp 402 may remain attached to the bone 52 for further manipulation and may facilitate easy manipulation of the bone via the clamp 402 throughout the remainder of the procedure.
[0106] 12H and 12I show jaws 411a', 411b' of an alternative bone clamp. The first jaw 411a' and the second jaw 411b' are the same as jaws 411a and 411b, except that each jaw 411a', 411b' includes a jaw extension 411ab, 411bb extending from its respective free end. As shown in FIG. 12I, when the first jaw 411a' and the second jaw 411b' are clamped to the humerus shaft 52, the first jaw extension 411aa and the second jaw extension 411bb meet and overlap such that the first jaw 411a' and the second jaw 411b' completely surround the circumference of the humerus shaft 52. Additionally, at least one of the first jaw extension 411aa and the second jaw extension 411bb can contact the bone 52 as a third contact point. Thus, the teeth 415 of the first jaw 411a' can form a first contact point or line, the teeth 415a and 415b of the second jaw 411b' can form a second contact point or line, and at least one of the jaw extensions 411aa and 411bb can form a third contact point or line. This embodiment can be particularly beneficial for slippery bones. In some cases, the bone clamp 402' can rotate, tilt, or otherwise adjust on the slippery bone due to gravity, causing it to move out of alignment with the bone 52. The closed ends of jaws 411a', 411b' closed by jaw extensions 411aa and 411bb help position the three contact points in the same plane and help maintain the position of bone clamp 402' on the slippery bone.
[0107] 13 illustrates an exemplary sounder 500 according to one embodiment of the present disclosure. The sounder 500 or reamer 500 can be used to assist in shaping the intramedullary canal of the humeral shaft 52 for receipt of the implant stem component 130 and the expandable trial stem 330. The sounder 500 can include an elongated shaft 502 and a reamer head 504 at a distal end of the shaft 502. The reamer head 504 can have a conical cutting profile configured to form a conical bore in the humeral shaft 52. Additionally, the shaft 502 can have depth markings 508 positioned along the shaft 502 to indicate the depth of the cutting head 504 within the bone.
[0108] 14A and 14B show an exemplary reamer planer 600 according to one embodiment of the present disclosure. The reamer planer 600 can also be used to assist in shaping the intramedullary canal of the humeral shaft 52 and to form a flat surface perpendicular to the intramedullary canal at the proximal end of the humeral shaft 52. The reamer planer 600 can include an elongated shaft 602, a reamer head 604, and a planing member 604. The reamer head 604 can have a conical cutting profile configured to form a conical bore in the humeral shaft 52. The reamer planer 600 can be mounted after the sounder 500. In this regard, the reamer head 604 can have a larger diameter than the sounder 500 such that the reamer head 604 provides the final shape of the bore in the humeral shaft 52. A planing member or planing plate 601 can be disposed between the elongated shaft 602 and the reamer head 604. The planing plate 601 can extend radially outward and can include a planing surface 603 oriented perpendicular to the longitudinal axis of the reamer head 604. The planing surface 603 can include cutting features configured to shape the proximal end of the resected bone 52 to form a flat surface and a bloody bone platform 144 that promotes bone growth into the porous distal surface 144 of the implant stem component 130.
[0109] 15A-15F illustrate an exemplary inserter / extractor handle assembly 700 according to one embodiment of the present disclosure. The handle assembly 700 generally includes a handle 710 and a connector 720 disposed at a distal end of the handle 710. The handle 720 can include a collar 712 at a proximal end that has a larger cross-sectional dimension than other portions of the handle 710 and can define a pushing surface 713 for pushing the handle 700 and any device connected thereto. The handle 710 can also include contours along its length to aid in easier gripping and can include one or more through holes 714 to reduce the weight of the handle 710. Also, as shown in FIG. 15B, an axial bore 716 can extend entirely through the handle 710 and the connector 720, allowing a driver, such as the driver 1200 shown in FIG. 19D, to be extended through the handle assembly 700 to engage a device connected thereto. Such a device may be, for example, an implant stem component 130 or an expandable stem trial 330. The axial bore 716 may also have a threaded portion 718 for threaded engagement with a slap hammer, for example, to assist in removal of such an implantable device.
[0110] The connector 720 generally includes a first portion 740 connected to a distal end of the handle 710 and a second portion 730 movable relative to the first portion 740 from a first position in which the adapter may engage the first portion 740 and a second position in which the second portion 730 also engages the adapter to secure the adapter to the handle assembly 700. Such an adapter may be any of the adapters described above, such as the adapter 140 of the implant stem component 130 with or without a taper protection insert, or the adapter 340 of the expandable trial stem 330.
[0111] An exemplary connector 720 is shown in FIGS. 15A and 15B and can include a connector body or first portion 740. The connector body 740 can be connected to a distal end of the handle 710 and can extend distally therefrom. The connector body 740 can be integrally connected to the handle 710 such that the connector body 740 and the handle 710 form a monolithic structure, or the connector body 740 and the handle 710 can be formed separately and modularly connected via pins, screws, taper fits, or the like. The connector body 740 can include a downwardly extending wall or flange 742 that can be disposed on one side of the handle assembly 710 and offset from its longitudinal axis. The connector body 740 can also include a pair of arms 744 that extend radially inward and can each be configured to engage a corresponding flat on the adapter, such as flats 149 and 349. Each arm 744 can also define a recess or slot 746 on its respective proximal side. Each such recess 746 can be configured to receive a shoulder, such as shoulders 141 and 341 .
[0112] The connector 720 may also include a sleeve or second portion 730. The sleeve 730 may include a cylindrical main body 732 that may be hollow and sized to cover at least a portion of the connector body 740. The sleeve 730 may also be movable in a proximal-distal direction relative to the connector body 740 between a first position and a second position. In this regard, the sleeve 730 may be connected to the main body 740 via a pin 750 that may extend through the sleeve 730 and into an axial slot 743 of the main body 740, as shown in FIG. 15B. As also shown in FIG. 15B, a spring 752 may be connected to the connector body 740 and the sleeve 730. The spring 752 may be a compression spring that biases the sleeve 730 toward the first position. The sleeve 730 can also include a proximal flange 736 that can extend circumferentially around the main body 740 at its proximal end, allowing a surgeon to pull the sleeve 730 up against the bias of the spring 752 to move the sleeve 730 from a first position to a second position. As best shown in FIG. 15C , the sleeve 730 can also include one or more projections 734 extending distally from the main body 732 and positioned opposite the longitudinal axis of the handle assembly 700 from the arm 744 of the connector body 740. In this regard, when the sleeve 730 is in the first position, a downwardly extending wall 742 of the connector body 740 and the projection 734 of the sleeve 730 can cooperate to define a cavity 722 configured to receive one of the adapters 140, 340 described above.
[0113] 15C-15E illustrate the act of coupling the handle to the adaptor 140 of the implant stem component 130. Although the adaptor 140 is illustrated without the taper protection insert 370, it should be understood that the procedure for coupling the handle assembly 700 to the adaptor 140 can be the same when the taper protection insert 370 is disposed within the tapered bore 148 of the adaptor 140. Additionally, the procedure is the same when connecting to the adaptor 340 of the expandable trial stem 330. As shown in FIG. 15C, prior to coupling the handle 700 to the adaptor 140, the connector 720 is prepared to receive the adaptor 140. In this regard, the sleeve 730 can be pulled proximally against the bias of the spring 752, and a proximal force is maintained on the sleeve 730 to keep the sleeve 730 in this proximal or unlocked position. In this proximal or unlocked position, arm 744 of connector body 740 is exposed, as is recess 746 proximal to arm 744. Arm 744 may be sized and shaped to contact corresponding flat 149 of adapter 140, and recess 746 may be sized and shaped to receive shoulder 141 of adapter 140.
[0114] 15D, handle assembly 700 is then slid laterally such that arms 744 slide laterally on flats 149 while sleeve 730 is maintained in the proximal or unlocked position. At this point, the user can simply release the force on sleeve 730 so that spring 752 is decompressed, allowing sleeve 730 to slide in distal direction D.
[0115] 15E shows sleeve 730 returned to a second or locked position in which each projection 734 covers a portion of main body 145 of adapter 140 and a corresponding arm 744. In this locked position, which is maintained by spring 752 in the absence of an applied force, lateral, axial, and rotational movement between adapter 140 and handle assembly 700 is prevented.
[0116] It should be understood that handle assembly 700 is merely exemplary of a handle assembly that may be used to connect to an adapter, such as adapters 140 and 340. Other inserter / extractor handles having other connector mechanisms may also be utilized, examples of which are described in the previously referenced '216 application, which is incorporated herein by reference.
[0117] 16A-16D illustrate an exemplary height measurement gauge 800 according to one embodiment of the present disclosure. The height measurement gauge 800 may include a main body 810, a pointer 820, and a clamp 830. The main body or scale 810 may be an elongated shaft having a generally symmetrical cylindrical shape to facilitate rotation of the clamp 830 about the scale 810. However, in some embodiments, the scale's face 812 may be flattened, such as to form a "D" shaped cross-sectional shape, as shown in FIG. 16D, for example. Such a flat face 812 may be positioned on the side of the scale 810 that faces the patient's glenoid cavity and may help prevent rotation of the clamp 820 about the scale 810. The scale 810 may include indicia 840 (e.g., hash marks with millimeter markings) provided thereon and may include a slot 817 (which may be closed at one or both axial ends) extending along the axial length of the scale 810. The slot 817 may define two openings 817a and 817b positioned approximately 180 degrees apart around the circumference of the scale 810, which facilitates the pointer 830 passing through the slot 817 and sliding axially.
[0118] The scale 810 can have a mating member or connector 811 at its distal end configured to couple to an adaptor, such as the adaptor 140 of the implant stem component 130 and the adaptor 340 of the expandable trial component 330, respectively. In this regard, the mating member 811 can include features similar to those of the trial proximal body 810 and the trial spacer 850. More specifically, the mating member 811 can include an inner leg or bend 813, an outer leg or bend 817, and a cleaning slot 817 extending through the outer leg 815. The inner leg 813 can be configured to mate with a shoulder and a recess, such as the shoulder 141, 341 and the recess 146, 346 of the respective adaptor 140, 340. However, it should be understood that this is merely exemplary and that any suitable coupling mechanism can be used to couple the scale 810 to the expandable trial stem 330 or implant stem 130.
[0119] The pointer 820 and the clamp 830 may cooperate to form the indicating member of the height measuring gauge 800. The pointer or stylus 830 may be a generally pin-shaped member having a point tip 822 intended to point to and / or contact the center of the patient's glenoid fossa 58 and a rear end 824 having a slightly larger diameter than the main shaft 826 of the pointer 820. The main shaft 826 of the pointer 820 may pass through a slot 817 in the scale 810. In some embodiments, the enlarged rear end 824 of the pointer 820 may have a diameter larger than the width of the slot 817 to ensure that the rear end 824 of the pointer 820 does not pass through the slot 817. However, this relationship is not required and any suitable feature (including an enlarged diameter) may be provided at the rear end 824 of the pointer 820 to facilitate a user's gripping and moving the pointer 820.
[0120] The clamp 830 may include an opening through which the scale 810 extends, a slider 832, and an arm 834 spaced from the slider 832. The slider 832 may include a generally "D" shaped opening that receives the "D" shaped scale 810 therethrough. The arm 834 may be disposed proximal to and otherwise aligned with the slider 832, and may be cantilevered from a proximal extension 837 of the slider 832 such that the arm 834 may be depressed toward the slider 832. The arm 834 may include a generally "D" shaped opening that receives the scale 810, and the openings in the slider 832 and the arm 834 may be generally aligned. However, the "D" shaped opening of the arm 834 can be slightly angled such that the shape of the opening of the arm 834 maintains the clamp 830 at its current height when no force is applied to the arm 834 against the slider 832. To slide the clamp 830 proximally or distally relative to the scale 810, the arm 834 can be pushed down towards the slider 832, which causes the angled hole in the arm 834 to reorient relative to the scale 810, allowing the clamp 830 to slide proximally or distally relative to the scale 810. As soon as the force on the arm 834 is released, the arm 834 returns to its original orientation, fixing the clamp 830 at its current height. The main shaft 826 of the pointer 820 can be used to read the indicia 812 on the scale that corresponds to the main shaft 826 to determine the indicated height of the proximal humeral prosthesis 100, as best shown in FIG. 16A.
[0121] The clamp 830 may also include a proximal extension 836 and a receiver 838 disposed on the proximal extension 836. The proximal extension 836 may be disposed proximally of the arm 834 and may extend from a proximal extension 837 of the slider 832. The proximal extension 836 may also have a "D" shaped opening, similar to the slider 832, through which the scale 810 is received. The receiver 838 may be a generally triangular shaped structure located on the proximal extension 836 and may define a through hole 833 for receiving the pointer 820. The receiver 838 may hold the pointer 820 in place by friction. For example, the receiver 838 may include a bent finger 839 terminating in an upwardly projecting protrusion that pushes against the pointer 820 when the pointer 820 is received in the receiver 838. The protrusions provide a baseline level of friction to the pointer 820 via the bent fingers 839, such that the pointer 820 tends to remain stationary when no force is applied (other than that applied by the bent fingers 839). A user can move the pointer 820 by pushing or pulling the pointer 820 with a pushing or pulling force that overcomes the friction from the protrusions of the bent fingers 839.
[0122] In use, after embedding the expandable trial stem 310 or implant stem component 110 into the humeral shaft 52, the measurement gauge 800, and in particular the mating member 811 of the scale 810, can be pressed against the adapter 340 in the same manner as described in relation to the trial spacer 350. At this point, the pointer 820 may be coupled to the clamp 830, but preferably is not. With the scale 810 coupled to the trial stem 310, the user can press the arm 834 down towards the slider 832 and, while holding it down, slide the clamp 830 to a position (height and / or angle) close to the patient's glenoid 58, as shown in FIG. 19E. If not already attached, the pointer 820 can be inserted into the through hole 833 of the receiver 838, and the position of the pointer 820 can be fine-tuned or otherwise adjusted until it points to the center of the patient's glenoid 58. At this point, the arm 834 can be released to temporarily relock the clamp 830 in position, and a height or distance measurement can be read by comparing the position of the main shaft 826 of the pointer 820 to the indicia 812 on the scale 810. This distance can be used for any desired purpose, including, for example, to better understand how the number and heights of trial spacers 350 and / or implant spacers 150 should be combined to construct the trial humeral prosthesis 300 or humeral prosthesis 100, respectively.
[0123] It should be understood that height gauge 800 is merely exemplary of a height gauge that may be used in a shoulder replacement procedure to determine the height of humeral prosthesis 100. Other height gauges may also be utilized, examples of which are described in the previously referenced '216 application, which is incorporated herein by reference.
[0124] 17A and 17B show an exemplary push-in stand 900 according to one embodiment of the present disclosure. As described above, the proximal body 110, the implant stem 130, and the spacer 150 can be connected together by a series of Morse taper locks to form the humeral prosthesis 100. This may require pushing the components together to fully seat the taper locks and secure the components relative to each other. The push-in stand 900 can be used in an operating room to aid in the assembly of the humeral prosthesis 100. The push-in stand 900 can be a generally hollow cylindrical structure that can include a base 902 and an elongated body 904 extending from the base 902. However, other shapes are also contemplated, such as, for example, a rectangular parallelepiped shape.
[0125] The body 904 extends along a longitudinal axis and terminates at a base 902 at a distal end and at an end cap or end plate 906 at a proximal end. The base 902 can have a diameter or cross-sectional dimension greater than a diameter or maximum cross-sectional dimension of the body 904 to provide stability and support to the body 904 during impaction. The body 904 includes a sidewall 909 that defines a cavity 901 configured to receive the implant stem component 130 therein. In this regard, a side slot 903 can extend through the sidewall 909 and into the endplate 906, the side slot 903 communicating with the cavity 901 and forming a notch 905 in the endplate 906. Such notch 905 can be defined by opposing rails 907 that can extend parallel to one another, as shown in FIG 17A, and can be spaced apart a distance configured to engage flats 149 of the implant stem adaptor 140, as shown in FIG 17B. A locking arm 910 can be connected to one end of the rails 907. A cam or slide member 912 can be connected to the locking arm 912 and configured to slide along the end plate 906 to move the locking arm 910 between the first and second positions.
[0126] In operation, the push-in stand 900 can be placed on a back table in an operating room so that the base 902 rests on the table. The implant stem 130 can be inserted through the side slots 903 into the cavity 901 so that the rails 907 engage the flats 149 of the stem adaptor 140 to hold and secure the stem component 130 in a suspended state, as shown in FIG. 17B. When the adaptor 140 is inserted into the notch 905 between the rails 907, it engages the locking arm 910, which moves the locking arm 910 from a first unlocked position to a second locked position, also shown in FIG. 17B. The sliding member 912 helps to hold the locking arm 910 in this position, which helps to hold the stem component 130 stationary in the notch 905 when the humeral prosthesis 100 is assembled thereto. In this regard, the spacer 150 can be pressed onto the stem component 130 and the proximal body 110 can be pressed onto the last spacer 150 in the stack. In this manner, the pressing stand 900 helps to provide a stable platform for assembly of the humeral prosthesis 100.
[0127] 18 illustrates an exemplary taper breaker tool 1000 according to an embodiment of the present disclosure. After assembling and trialing the humeral prosthesis 100, it may be desirable to remove the implant spacer 150 and / or replace it with another spacer 150 of a different length. In this regard, the taper breaker tool 1000 may be configured to break the spacers 150 from one another, from the stem component 130, and / or from the proximal body 110. As illustrated, the taper breaker tool 1000 may include a stationary block 1004, a drive member 1005, a movable block 1006, and a handle 1009. The stationary block 1004 may include a first member 1001, a second member 1002, and a third member 1003 configured in a U-shape. The third member 1003 may include a first wedge 1008a extending in a direction towards the first member 1001. The movable block 1006 may also include a second wedge 1008b, and the movable block 1006 may be disposed adjacent to the first member 1001 such that the second wedge 1008b of the movable block 1006 faces the first wedge 1008a of the third member 1003. The drive member 1005 may extend through the first member 1001 and may be connected to the movable block 1006 to drive the movable block 1006 towards the first wedge 1008a of the third member 1003. In this regard, the drive member 1005 can be threadedly coupled to the first member 1001 to facilitate a drive action that enables the wedges 1008a and 1008b to pry apart the taper locked components, as shown in FIGURE 19L. A handle 1009 can extend from the first member 1002 and / or the second member 1003 to facilitate manipulation of the taper separation tool 1000.
[0128] The implants, trials, and instruments described above may be provided as a system. In this regard, the humerus replacement system may include, for example, the humerus prosthesis 100 with all of its components, the trial humerus prosthesis 300 with all of its components, the reverse style trial and humeral head trial components 200, 210, 220, 230, 250, and instruments such as the bone clamp assembly 400, the sounder 500, the reamer planer 600, the inserter / extractor handle assembly 700, the height measurement gauge 800, the pusher stand 900, and the taper separation tool 1000.
[0129] In addition to those described above and illustrated in the figures, various other operations are now described with reference to Figures 19A-19M. It should be understood that the following operations do not have to be performed in the exact order described below. Instead, various operations may be treated in different orders or simultaneously. Also, unless otherwise noted, operations may be omitted or added.
[0130] In an exemplary method of replacing the proximal humerus 53, the proximal humerus 53 can be resected. This can be accomplished by clamping the bone clamp assembly 400 at a desired location along the length of the humerus shaft 52, as shown in FIG. 19A. The bone clamp 402 can be adjusted until the drop rod 440 extending through the second jaw 411b is aligned parallel to the shaft axis of the humerus shaft 52, thereby causing the resection guide slot 424 and the resection guide surface 424 to be aligned perpendicular to the humerus shaft 52. As described above, the teeth 415 of the clamp jaws 411a and 411b can assist in aligning the resection guide 420 perpendicular to the shaft axis. Once parallel alignment is achieved, the knob 450 is tightened to secure the clamp 402 to the bone 52. It should be noted that the resection guide 420 can be connected to the bone clamp 402 in the manner previously described before or after the bone clamp 402 is secured to the bone 52 .
[0131] Thereafter, a bone saw is guided through the bone 52 along the proximal guide surface 422 to remove the proximal portion 53 of the humerus 50. Alternatively, a bone saw may be guided through the capture guide slot 424 to resect the proximal humerus 53. Once the proximal portion 53 of the humerus 50 has been resected, the resection guide 420 may be disconnected from the second jaw 411b while the bone clamp 402 remains connected to the humerus shaft 52 such that a portion of the bone extends proximally from the jaws 411a and 411b, as shown in FIG. 19B. The clamp 402 may remain attached to the bone 52 throughout the remainder of the procedure to aid in manual manipulation and control of the bone. Additional bone shaping operations may then be performed. For example, the cutting head 504 of the sounder 500 may be inserted into the intramedullary canal 56 of the shaft and used to shape the intramedullary canal 56 for receipt of the stem component 130. Subsequently, or alternatively, the reamer head 604 of the reamer planer 600 can be inserted into the intramedullary canal 56 to further shape the intramedullary canal 56 while the planer plate 601 simultaneously cuts the proximal end of the humeral shaft 52 to form a flat proximal surface.
[0132] The inserter / extractor handle assembly 700 can be connected to the adaptor 340 of the expandable stem 330, as shown in FIGS. 15C-15E and 19C. In this regard, the sleeve 730 of the handle assembly 700 can be pulled proximally against the bias of the spring 752 to expose the arm 744. The arm 744 can then be slid into engagement with the flat 349 on the adaptor 340 of the expandable stem 330 such that the shoulder 341 is received in a corresponding recess 746. The sleeve 730 can then be released such that the compression of the spring 752 advances the sleeve 730 over the adaptor 740 to secure the handle assembly 700 relative to the expandable trial stem 330. The pivot rod 1100 can be connected to the proximal end of the handle 710 and to the adaptor 340 of the expandable stem 330, as shown in FIG. 19C.
[0133] The expandable trial stem 330 can then be inserted into the bone 52 such that the adaptor 340 is positioned at the proximal end of the resected bone 52. The trial stem 330 can then be rotated within the bone until the desired rotational alignment is achieved. Once the expandable trial 330 is inserted into the bone 52 and the desired rotation is achieved, the driver 1200 can be inserted through the handle assembly 700 into the adaptor 340 and engaged with the expansion bolt 335. The driver 1200 can then be rotated in a first direction, thereby driving the expansion bolt 335 distally, thereby moving the first stem portion 337a and the second stem portion 337b radially outwardly into engagement with the bone 52 to secure the trial stem 330 thereto. The handle can then be removed by again pulling the sleeve 730 proximally to a second position and sliding the arms 744 away from the flats 149.
[0134] In some embodiments, an expandable trial stem 330 may not be used. Instead, the implant stem component 130 may be embedded and then used for subsequent trialing. In such embodiments, the inserter / extractor handle assembly 700 may be attached to the adaptor 140 of the stem component 130 as described above in connection with the expandable trial stem 330. However, prior to connecting the handle assembly 700 to the adaptor 140 of the stem component 130, the taper protective insert 370 may be inserted into the tapered bore 142 of the adaptor 140 with the post 378 extending proximally therefrom. Additionally, prior to expansion of the stem 132, rather than placing the stem 132 in the bone 52 as in the case of the first stem portion 337a and the second stem portion 337b, the stem component 130 may be rotated to a desired rotation position and impacted into the bone 52 using the handle 710. The taper protector 370 helps protect the tapered bore 142 and the adapter 140 during impaction. The handle assembly 700 can then be removed from the adapter 140, leaving the taper protector insert 370 in the adapter 140.
[0135] The height gauge 800 may then be connected to the adaptor 340 of the expandable stem trial 330 (or the adaptor 140 of the implant stem component 130, if used instead). In this regard, the fitting 811 may be positioned over the adaptor 340 and then pushed distally into the adaptor 340, such that the inner leg 813 snaps into a locked arrangement with the recess 346 and shoulder 347. In addition, the flats 348a and 348b in the fitting 811 at the post 348 engage with one another such that the clamp 830 and the pointer 820 point towards the glenoid 58. The arm 834 of the clamp 830 is then pressed down to slide the clamp 830 up or down along the scale 810 until the pointer tip 822 is positioned at the center of the glenoid 58, as shown in FIG. 19E. The pointer 830 may also be slid medially towards the glenoid 58 until it contacts the center point of the glenoid 58. The arm 834 of the clamp 830 can be released to secure the clamp 830 in place on the scale 810. The height measurement can then be read by referencing the indicia 812 relative to the pointer 820.
[0136] Based on the height measurements obtained via the height gauge 800, one or more trial spacers 350 can be selected to match the measured height. For example, as shown in FIG. 19F, a first trial spacer 350a corresponding to a height of 20 mm and a second trial spacer 350b corresponding to a height of 30 mm can be selected for a total height of 50 mm. The first trial spacer 350a can then be connected to the adapter 340 by pressing the spacer 350a onto the adapter 340 until its inner leg 352 snaps into place. As shown in FIG. 19F, the second trial spacer 350b can be similarly pressed onto the first trial spacer 350a, and the proximal trial body 310 can be pressed onto the second trial spacer 350b. The corresponding flats 348a, 348b of the adapter posts 348 and flats 356a, 356b of the spacer posts 356 ensure that the trial proximal body 310 is properly oriented towards the glenoid fossa 58.
[0137] An appropriate trial joint component can then be assembled to the trial proximal body 310. Some procedures may utilize a reverse joint construction in which the prosthesis is constructed inversely to that of the natural joint. In a natural joint, the humeral head 51 is a convex structure that articulates with a concave glenoid cavity 58. However, in a reverse procedure, the prosthesis is reversed so that the humeral joint component includes a concave articular surface and the glenoid cavity includes a convex glenosphere for articulating with the concave articular surface of the humeral prosthesis. As shown in FIG. 19G, if a reverse joint construction is desired, the trial tray 220 can be coupled to the proximal body 310 by inserting the boss 222 into the scalloped opening 321 in the trial proximal body 310. A screw, such as screw 257, can be inserted through a through hole 229 in the trial tray 220 and engaged with a threaded opening 325 in the proximal body 310. The reverse insert 210 can then be connected to the tray 220 and engaged with the trial glenosphere to assess joint function with a particular anatomic configuration, as shown in FIG. 19H. Initial trialing in this regard can be performed with the trial tray 220 in a first eccentric configuration, such as that shown in FIG. 5E, corresponding to neutral or no eccentricity. If it is determined that eccentricity is required, the tray 220 can be rotated so that the tray 220 is positioned in a second eccentric configuration, such as that shown in FIG. 5F. The trialing of the joint is then repeated. Additional eccentricity can be added until the desired eccentricity is achieved.
[0138] In procedures where a standard, i.e., non-reverse style, prosthesis is desired, the humeral head union trial 250 and humeral head trial 230 can be connected to the trial proximal body 310 in the same manner as described with respect to the trial tray 220 and reverse style insert 210, and the trials can be advanced in the same manner until the proper eccentricity is achieved. Also, if it is determined that the height of the humeral trial prosthesis 300 is not sufficient, one or more of the trial spacers 350a and 350b can be replaced with another trial spacer configuration having a different overall height.
[0139] After trialing with the trial humeral prosthesis 300, the humeral prosthesis 100 can be constructed to match the height and eccentricity determined through the trialing motion. In this regard, implant spacers, such as the first spacer 150a and the second spacer 150b, can be selected to match the height of the trial humeral prosthesis 300. The humeral prosthesis 100 can be assembled on the back table using the push stand 900 as described above.
[0140] However, prior to assembling the articulation component 260 to the implant proximal body 110, additional trialing can be performed using the humeral prosthesis 100. In this regard, the connector 205 of the proximal body adaptor 200 can be inserted into the second bore 122 of the proximal body 110 such that the flange 201 extends over the first bore 121, as shown in FIG. 3C and FIG. 19J. The trial tray 220 or humeral head coupler trial 250 can then be connected to the proximal body 110 with the eccentricity determined from the trialing with the trial humeral prosthesis 300. This construct can then be trialed for functionality before final assembly. In some embodiments of the surgical procedure, the trial humeral prosthesis 300 may not be utilized for trialing. Instead, the humeral prosthesis 100 can be used for all trialing. Use of the height gauge 800 minimizes the risk of the prosthesis having an inappropriate height and requiring disassembly during the trialing process, which may otherwise prohibit use of the humeral prosthesis 100 as a trial.
[0141] However, in some circumstances, it may be determined that the humeral prosthesis 100 is too short or too tall. Thus, when trialing the humeral prosthesis 100, it may be desirable to remove one or more of the implant spacers 150a and 150b and / or replace one or more of the implant spacers 150a and 150b with one or more implant spacers 150a-150d of different sizes. However, this may prove difficult due to the taper lock between the spacers 150a and 150b and between the spacers 150a and 150b and the stem component 130 and the proximal body 110. A taper separation tool 1000 may then be used that can separate the spacers 150 easily and while protecting the bone-stem interface. In this regard, the taper separation tool 1000 may be positioned along the humeral prosthesis 100 such that the first wedge 1008a and the second wedge 1008b are aligned with the desired interface. Such an interface may be between adjacent implant spacers 150, between a spacer 150 and an adaptor 140 of the stem component 130, or between a spacer 150 and the implant proximal body 110. The drive member 1005 may then be driven to push the movable block 1006 towards the first wedge 1008a, thereby separating the desired components.
[0142] Once trialing is sufficiently complete, the articular component 260 may be assembled to the proximal body 110 and the soft tissue may be sutured to the humeral prosthesis 100. In this regard, some soft tissue structures, such as, for example, a portion or all of the rotator cuff muscles, may be attached to the implant proximal body 110 via sutures such that the soft tissue is compressed against the porous patch 117. Other soft tissue structures, such as, for example, a portion of the deltoid and rotator cuff muscles, may be attached to one or more of the implant spacers 150a and 150b such that the tissue is compressed against the porous ring 156.
[0143] The above-described devices, systems, and methods have been described in the context of a manually performed humerus replacement procedure. However, in some embodiments, the replacement of the proximal humerus portion 53 with the humerus prosthesis 100 may be performed robotically or with the assistance of a computer-assisted surgery ("CAS") system.
[0144] FIG. 20A is a schematic diagram of an exemplary CAS system 2000. In this regard, the CAS system 2000 may include a haptic device 2030 to assist in guiding a surgeon in performing various operations of a procedure, such as bone cutting. However, it should be understood that the system 2000 may also be utilized in robotic surgery, where an autonomous or semi-autonomous robot is utilized to perform such operations in lieu of the haptic device 2030. The CAS system 2000 may also include a display device 2010, an input device 2012, and a processor-based system 2016, which may include a visual tracking system that may include, for example, a computer 2040 having a processor and a storage medium 2014, and one or more cameras 2020 that may be communicatively connected to the processor-based system 2016. One example of a CAS system that may be utilized to replace a proximal humerus is described in more detail in U.S. Pat. No. 7,831,292, the disclosure of which is incorporated herein by reference.
[0145] A surgical procedure to replace a proximal humerus utilizing the CAS system 2000 can begin by registering a target anatomy of a patient (i.e., the humerus 50) with the system 2000. This can be performed by connecting an anatomy tracker 2050 to the humerus 50. The anatomy tracker can include a marker array that can include a plurality of markers 2052 arranged in a predetermined arrangement. Each of the markers 2052 can be an active marker or a passive marker. An example of an active marker is a light emitting diode ("LED"). An example of a passive marker is a reflective marker, such as a ball-shaped marker having a surface that reflects incident infrared radiation. Regardless of the marker 2052 utilized, the camera 2020 can be configured to detect and track the markers 2052 such that the position of such markers 2052 in the operating coordinate space can be communicated to the processor-based system 2016 so that the processor can map such position to a virtual coordinate space. This allows surgery to be performed on anatomical structures via the haptic device 2030 or an autonomous or semi-autonomous robot according to a pre-operative plan.
[0146] Once the anatomy tracker 2050 is connected to the bone 50, a probe (not shown), also having a marker array, can be used to contact various points on the humerus 50. The processor-based system 2016 associates the position of the probe with the position of the anatomy tracker 2050 on the bone 50 such that the particular anatomy of the humerus 50 can be mapped to a virtual coordinate system. Thus, once registration of the humerus 50 is complete, various surgical procedures can be performed on the humerus 50, such as resecting the proximal humerus portion 53 along the humeral shaft 52 and reaming the intramedullary canal of the humeral shaft 52.
[0147] In some methods of performing robotic or CAS surgery, the anatomy tracker 2050 may not be connected to the bone 50, but instead may be connected to the bone clamp 402 as shown in FIG. 20B. As shown in FIG. 20B, the anatomy tracker 2050 may be connected to the second jaw 411b of the bone clamp, such as in the second hole 413b. However, in other embodiments, the anatomy tracker 2050 may be connected to the bone clamp 402, for example, at another location on the second jaw 411b or in one of the first handle 410a and second handle 410b. The anatomy tracker may remain connected to the bone clamp 402 during surgery, or may be detached and connected as needed during various stages of surgery. In either case, registration of the humerus 50 can be performed using the anatomical structure tracker 2050 while the tracker 2050 is connected to the bone clamp 402 and the bone clamp 402 is clamped to the humerus 50.
[0148] After the humerus is registered with the CAS system 2000, various operations can be performed on the bone using the CAS system 2000. For example, the haptic device 2030 can be used to guide cutting tools, such as a rotary burr and bone saw, connected thereto through the humerus shaft 52 proximal to the jaws 411a and 411b of the bone clamp 402. Similarly, if an autonomous or semi-autonomous robot is utilized, such a robot can perform a cutting operation to remove the proximal humerus 53. With the bone clamp 402 and anatomical structure tracker 2050 still connected to the bone, further operations can be performed using the haptic device 2030 or the robot. Such operations can include, for example, reaming of the intramedullary canal of the bone.
[0149] 21 illustrates an exemplary humeral prosthesis 2100 according to another embodiment of the present disclosure. Unlike the humeral prosthesis 100, the humeral prosthesis 2100 is configured for implantation into the humerus 50, such as in a primary or revision surgery in which sufficient bone stock exists to encapsulate the prosthesis 2100, as described above with respect to FIG. 9E. In this regard, the humeral prosthesis 2100 may include a metaphyseal portion 2102 and a stem 2104 extending from the metaphyseal portion 2102. The stem 2104 may be configured to be positioned within the intramedullary canal of the humerus 50, and the metaphyseal portion 2102 may be configured to be positioned within the metaphyseal portion of the humerus 50 so as to be recessed within the proximal end of the humerus 50 or substantially flush with the proximal end of the humerus 50. The humeral prosthesis 2100 can be configured for cement implantation, whereby the stem 2104 can have a plurality of grooves 2106 configured to receive a cement coating that is thick enough to secure the stem 2104 to the bone 50, for example. In other embodiments, the humeral prosthesis 2100 can be configured to be press fit into the humerus 50 and can include a porous exterior along at least a portion of the metaphyseal portion 2102 to promote bone ingrowth. The metaphyseal portion 2102 can also include a bore 2108, which can be similar to the bore 121, and thereby can be configured to receive any of the final implant and trial components described above with respect to Figures 3A-8B. The bore 2108 can also be configured to receive a modular adaptor, as described below.
[0150] 22 illustrates an exemplary humeral trial prosthesis 2110 according to another embodiment of the present disclosure. The humeral trial prosthesis or humeral broach 2110 is a trial prosthesis corresponding to the humeral prosthesis 2100. As such, the humeral trial prosthesis 2110 can have a similar geometry to that of the humeral prosthesis 2100 and can include a metaphyseal portion 2112 and a stem 2114. Also, like the humeral prosthesis 2100, the humeral trial 2110 can include a bore 2118, which can be a scalloped bore, such as bore 321, or a smooth bore, such as bore 121. The stem 2114 can be an expandable stem, such as the expandable trial stem 332. However, in other embodiments, the humeral trial prosthesis 2110 may be configured as a broach, and the stem 2114 and / or metaphyseal portion 2112 may include cutting teeth or broaching surfaces configured to remove bone from the humerus 50 to match the geometric contours of the trial prosthesis 2110. When used as a broach, the humeral trial prosthesis 2110 may be left in the humerus 50 after broaching to perform a trial procedure, as discussed further below.
[0151] 23A illustrates a modular adapter 2120 according to one embodiment of the disclosure. The modular adapter or plug 2120 can include a proximal portion 2112, a distal portion 2124, and an annular flange or disk 2123 disposed between the proximal portion 2122 and the distal portion 2124. The proximal portion or first portion 2122 can include a spline section that can include a plurality of splines 2125 arranged circumferentially about a longitudinal axis of the modular adapter 2120 such that each spline 2125 extends in a proximal-distal direction. The proximal portion 2122 can also include a connection mechanism that can include a plurality of flexures or flexible arms 2127, as illustrated, that extend proximally from the spline section and can be movable radially inward from a first position to a second position. The proximal portion 2122 can include two or more flexures 2127, such as, for example, two flexures 2127. A circumferential groove 2129 may be disposed between the annular flange 2123 and the splined section to facilitate engagement of a removal tool (not shown). The distal or second portion 2124 may extend distally from the annular flange 2123. The distal or second portion 2124 may also include a connection mechanism that may include a plurality of distally extending flexures or flexible arms 2128. As an example, the distal portion 2124 may include two or more flexures 2128, such as, for example, three flexures 2128. The flexures 2127, 2128 of the proximal and distal portions 2122, 2124 provide a snap-fit connection with the humeral head trial (described below) and bores 2108, 2118 of either the humeral prosthesis 2100 or the humeral trial prosthesis 2110. However, other connection mechanisms are contemplated, such as, for example, a threaded connection or a taper-fit connection.
[0152] The modular adapter 2120 can be made of a radiopaque material. For example, the modular adapter 2120 can be made of a biocompatible polymer, such as Radel® R5000, in which a radiopaque material is added to the polymer composition. Such a radiopaque material can include, for example, radium sulfate. This can facilitate visualization of the modular adapter 2120 via fluoroscopy or other medical imaging during surgery to assess the eccentric axis of the humeral head trial during surgery, and can also assist in locating the modular adapter 2120 within the patient's surgical wound if unintentionally left in the patient.
[0153] 23B illustrates a humeral head trial 2130 according to another embodiment of the present disclosure. The humeral head trial 2130 can include an articulation side 2131 and an articulation side 2132. The articulation side 2131 can include a convex articular surface 2133. The articulation side 2132 can include a cavity 2137 extending therethrough and can define a circumferential rim 2135 that defines an outer periphery of the humeral head trial 2130. A boss or central body 2134 can be disposed within the cavity 2137. The body 2134 can include a first opening 2133a and a second opening 2133b extending therethrough. As shown in FIG. 23B, the first opening 2133a can define a central axis CA6 and the second opening 2133b can define a central axis CA7. The central axis CA6 and the central axis CA7 can be parallel and offset from each other by a distance D4. The distance D4 can at least partially determine the potential offset of the humeral head trial 2130, and the offset can be, for example, 1 mm to 4 mm. The central axis CA6 of the first opening 2133a can be coaxial with the central axis of the modular humeral head trial 2130 such that the axis CA6 substantially intersects the apex or center of the articular surface 2133. The first opening 2133a and the second opening 2133b can intersect with each other to form a larger oval opening. In other words, the first opening 2133a and the second opening 2133b can each define a radius, and the distance D4 can be less than the sum of the radii of the first opening 2133a and the second opening 2133b. The first opening 2133a and the second opening 2133b can include splines or scallops 2136 arranged around their respective peripheries. In this regard, each of the first opening 2133a and the second opening 2133b are configured to receive the proximal portion 2122 of the modular adapter 2120, respectively, such that the splines 2125 thereof, when spaced apart, index with the splines 2136 of the first opening 2133a and the second opening 2133b.
[0154] 23C-23E illustrate a modular humeral head assembly 2140, which may include a humeral head trial 2130 and a modular adaptor 2120. In this regard, the modular adaptor 2120 may be connected to the modular head trial 2130 in either a first eccentric arrangement or a second eccentric arrangement. In the first eccentric arrangement, the proximal portion 2122 of the modular adaptor 2120 may be received within the first opening 2133a of the humeral head trial 2130 such that the splines 2125 are aligned with the splines 2136 of the first opening 2133a to inhibit relative rotation and the longitudinal axis of the modular adaptor 2120 is coaxial with the central axis CA6. The bend 2127 of the proximal portion 2122 forms a quick connect / disconnect mechanism that secures the modular adaptor 2120 to the humeral head trial 2130 while allowing it to be disconnected from the humeral head trial 2130 during trialing. The first eccentricity arrangement may be a neutral eccentricity, as shown in FIG 24 where the distal portion 2124 of the modular adaptor 2120 is received within the bore 2118 of the trial prosthesis 2110 and the central axis CA6 is coplanar with the longitudinal axis A12 of the humeral trial prosthesis 2110. Thus, the humeral head trial assembly 2140 is centered relative to the trial prosthesis 2110 in the AP direction.
[0155] In the second eccentric arrangement, the proximal portion 2122 of the modular adapter 2120 can be received within the second opening 2133b of the humeral head trial 2130 such that the splines 2125 are aligned with the splines 2136 of the second opening 2133b and the longitudinal axis of the modular adapter 2120 is coaxial with the central axis CA7 of the second opening 2133b. Again, the bend 2127 facilitates a quick connect / disconnect mechanism that secures the modular adapter 2120 to the humeral head trial 2130. The second eccentric arrangement can define an anterior or posterior eccentricity having a magnitude of D4. 25, where the distal portion 2124 of the modular adaptor 2120 is received in the bore 2118 of the artificial head trial 2110, with the longitudinal axis A12 of the humeral trial prosthesis 2110 being coplanar with the central axis CA7. As shown, the central axis CA6 is offset anteriorly or posteriorly by a distance D4. It should be noted that the distal portion 2124 of the modular adaptor 2120 can be aligned with the bore 2118 of the trial prosthesis 2110 to provide multiple orientations, such that the modular head assembly 2140 can provide anterior and posterior eccentricity depending on the orientation of the modular adaptor within the bore 2118. This can be done via splines or scallops 2116 in the bore 2118 and corresponding splines in the distal portion 2124.
[0156] In use, the humeral trial prosthesis 2110 can be inserted into the proximal end of the humerus 50 and the broaching surface can be used to create a bone cavity. The trial 2110 can be left in the bone and the humeral head trial 2130 can be assembled with the modular adaptor 2120 in either the first eccentric arrangement or the second eccentric arrangement. The humeral head trial assembly 2140 can then be connected to the bore 2118 of the trial prosthesis 2110 via the bend 2128 of the distal portion 2124 of the modular adaptor 2120. Trialing with the glenoid component can then be performed. If a different eccentricity is ultimately desired, the humeral head trial assembly 2140 can be removed from the humeral trial prosthesis 2110 and the modular adaptor 2120 can be moved to the other of the first opening 2133a and the second opening 2133b to provide a different eccentric arrangement. Alternatively, a different humeral head trial 2130 having a different D4 offset dimension can be utilized, if desired. Thus, multiple humeral head trials 2130 having different offsets to accommodate different eccentric placements can be provided in a kit. The humeral head trial 2130 can then be reconnected to the trial prosthesis 2110 and trialing can be performed again. Once the humeral prosthesis 2100 is implanted after this initial trialing, a secondary trialing can be performed again using the humeral prosthesis 2100 and humeral head trial assembly 2140 in the same manner.
[0157] Although the invention has been described herein with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications can be made to the illustrative embodiments and that other arrangements can be devised without departing from the spirit and scope of the invention as defined by the appended claims.
Claims
1. 1. A system for replacing a proximal humerus, comprising: a prosthesis body having a first superior surface, an anterior surface, a posterior surface, an lateral surface, an inner surface, and a first bore extending through said first superior surface, said first bore having a plurality of scallops arranged about a central axis of said first bore; a joint component having a component body and a boss extending from the component body, the component body having an articulation surface disposed thereon, the boss configured to be received within the first bore and having a protrusion extending radially outwardly and configured to engage one of the scallops; A system comprising:
2. the component body includes a central axis, the boss defines a boss axis, the central axis being offset from the central axis; The system of claim 1 , wherein the prosthesis body includes a midline plane that bisects the prosthesis body and extends in a superior-inferior direction and a medial-lateral direction.
3. 3. The system of claim 2, wherein the joint component has a first eccentric orientation relative to the prosthesis body, in which the protrusion engages a first scallop and the central axis and boss axis of the component body lie coplanar with the midline plane.
4. 4. The system of claim 3, wherein the joint component has a second eccentric orientation relative to the prosthesis body, in which the projection engages a second scallop, the boss axis lies coplanar with the midline plane, and the central axis of the component body is offset in one of an anterior and a posterior direction relative to the midline plane.
5. 5. The system of claim 4, wherein the component body includes a central opening coaxial with the central axis of the body and a through bore extending through the component body and the boss, the through bore being coaxial with the boss axis.
6. The system of claim 4 , wherein the articular surface is a concave articular surface.
7. The system of claim 4 , wherein the articular surface is a convex articular surface.
8. 3. The system of claim 2, wherein the joint component includes a reverse-type trial insert having a concave articular surface, and the component body is a tray having an inner surface bounded by a rim, the rim and the inner surface cooperatively defining a cavity configured to receive the reverse-type trial insert.
9. the articular component includes a humeral head trial having a convex articular surface and a socket disposed opposite the convex articular surface; The system of claim 2 , wherein the component body is configured to be received within the socket of the humeral head trial.
10. 10. The system of claim 9, wherein the component body includes an axial slot, and the articulation component includes a rib disposed in the socket, the rib configured to be received in the axial slot of the component body.
11. The system of claim 1 , wherein the prosthesis body includes a second bore extending therethrough.
12. 12. The system of claim 11, further comprising a trial adaptor having a connecting portion receivable within the second bore and a flange extending from the connecting portion, the flange having an opening extending therethrough that at least partially defines the first bore of the prosthesis body when the connecting portion is received within the second bore, and the scallop is disposed within the flange about the opening.
13. The system of claim 1 , wherein the outer surface of the prosthesis body includes a spherical curvature, and the anterior and posterior surfaces are each flat and intersect with the first superior surface, the lateral surface, and the medial surface, respectively.
14. 14. The system of claim 13, wherein the prosthesis body includes a first suture opening and a second suture opening, the first suture opening defining a first suture opening axis and the second suture opening defining a second suture opening axis, the first axis and the second axis intersecting at an angle Θ.
15. The system of claim 14 , wherein the anterior surface includes a porous patch, and at least one of the first suture opening axis and the second suture opening axis overlaps the porous patch.
16. 14. The system of claim 13, further comprising a stem component having a stem and an adaptor connected to the stem, the stem configured to be received within an intramedullary canal of the humerus.
17. The system of claim 16 , wherein the adapter includes a radially protruding collar having a porous distal surface.
18. 17. The system of claim 16, further comprising a spacer connectable to the proximal body and the adapter of the stem component, the spacer having a first porous ring and a first suture opening and a second suture opening, the first spacer suture opening being disposed adjacent to an upper portion of the first porous ring and the second spacer suture opening being disposed adjacent to a lower portion of the first porous ring.
19. 17. The system of claim 16, further comprising a spacer connectable to the proximal body, radially movable, and having a pair of legs configured to connect to the adapter of the stem component in a snap-fit manner.
20. 17. The system of claim 16, wherein the stem of the stem component includes a first stem portion and a second stem portion and an expansion driver disposed between the first stem portion and the second stem portion, the expansion driver configured to move the first stem portion and the second stem portion in a radially outward direction.