Glenoid component for shoulder prosthesis and related shoulder prosthesis
The glenoid component with a predetermined offset and increased thickness addresses the challenges of correcting glenoid erosions by simplifying surgical procedures and ensuring effective bone defect correction and prosthetic integration.
Patent Information
- Application Number
- JP2025092278
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2019-11-18
- Filing Date
- 2025-06-03
- Publication Date
- 2025-09-09
AI Technical Summary
Existing shoulder prosthetic surgery techniques face challenges in correcting glenoid surface erosions and deformities, particularly due to the need for significant bone removal and complex grafting procedures, which can lead to suboptimal results and mechanical issues.
A glenoid component with a predetermined offset between its attachment and prosthesis surfaces, providing increased thickness to compensate for bone defects, allowing for standardized and simplified surgical correction without extensive milling, and facilitating easy integration with bone pins and prosthetic components.
The solution enables efficient and precise correction of various bone defects, ensuring proper tensioning of soft tissues and mechanical stability, while allowing for quick and intuitive surgical application and compatibility with different prosthetic components.
Smart Images
Figure 2025131674000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to a glenoid component for a shoulder prosthesis including a glenoid joint and a prosthetic joint. The present invention also relates to a shoulder prosthesis including a glenoid component.
[0002] Generally, the present invention finds application in the prosthetic orthopedic field of shoulder surgery. (Prior Art)
[0003] Glenoid surface erosion is a fairly common factor in the art and must be considered in the context of shoulder prosthetic surgery.
[0004] Indeed, to achieve a good mid- to long-term result, during surgery it is necessary not only to re-establish proper tension in the soft tissues, but also to attempt to repair any bone defects that may be present that could lead to the problem of subluxation of the humeral head.
[0005] There are various types of glenoid erosions. Posterior ones are the most common, but there are also glenoid deformities with superior erosions, lower inclinations, and central defects. All of these individual defects are often combined together in specific cases. For example, a lower glenoid deformity combined with a posterior erosion is one of the more common conditions seen in osteoarthritis patients.
[0006] Therefore, during surgery, it is important to properly identify the type of defect and correct it by restoring the glenoid morphology to a neutral state. For example, a prosthetic humeral head that articulates off-center can cause excessive premature wear of the polyethylene component as well as glenoid component failure due to a phenomenon known as "rocking horse."
[0007] The prior art has sometimes ameliorated this type of crisis by asymmetrical milling of the glenoid surface to return the glenoid to its original neutral configuration.
[0008] Although this measure constitutes a solution that is still used today, it has drawbacks, particularly related to the disadvantage that asymmetric milling of the surface requires the removal of a significant portion of bone to correct the defect, which requires subsequent lateralization of the component to properly tension the soft tissue.
[0009] A further technique in use today involves the insertion of a bone graft into the defect area. A disadvantage of this technique is the difficulty of retrieving the graft. In fact, the graft is usually obtained from a bone bank or directly from a patient who has undergone surgery (e.g., removal of a bone graft from the iliac crest), which can be painful and require a long recovery time. Furthermore, this technique has the disadvantage of involving a particularly complex grafting technique that is subject to the possibility of human error, which can lead to suboptimal results in the correction of the bone deformity and, consequently, in the prosthetic connection.
[0010] These problems can be overcome by using augmented prosthetic components, such as those encompassed by the present invention, in particular, the implantation technique is much easier for any user skilled in the art and at the same time allows obtaining good results. Summary of the Invention
[0011] The object of the present invention is to overcome the drawbacks of the prior art.
[0012] A further object is to provide components that are adapted to provide particular benefits to a glenoid prosthetic system.
[0013] A further object is to provide components that are adapted to provide greater convenience for application or use by the surgeon.
[0014] A particular object of the present invention is to provide a device that allows for the repair of typical bone defects of varying severity.
[0015] A further specific object of the present invention is to provide a solution that allows a surgeon to make an immediate and standardized selection at the stage of surgery.
[0016] Yet another particular object is to provide a solution that allows for simple application by the surgeon.
[0017] Another specific object is to provide a structure of increased specific dimensions for the correction of bone defects.
[0018] A further specific object is to provide a component that allows for quick coupling with further devices for prosthetic surgery, such as bone pins.
[0019] Finally, a particular object of the present invention is to provide a device that is particularly suited to standard production processes for prosthetic components.
[0020] These and other objects are achieved by a glenoid component according to the features of the appended claims, which form an integral part of this specification.
[0021] The underlying idea of the present invention is to provide a glenoid component for a shoulder prosthesis, the glenoid component comprising a glenoid attachment surface adapted for attachment to bone and having a first convex portion including a first outer edge defining a development plane, and a prosthesis attachment surface opposite the glenoid attachment surface and adapted to receive a second prosthesis component of the shoulder prosthesis, the prosthesis attachment surface having a second portion including a second outer edge defining a reference plane. The glenoid component provides a predetermined offset between the development plane and the reference plane to define an increased thickness of the glenoid component, the increased thickness adapted to adequately compensate for bone defects.
[0022] Advantageously, the present invention provides surgeons with a standard solution to a variety of typical deformity situations of varying severity encountered in shoulder surgery.
[0023] In particular, the increased thickness of the glenoid component is defined by a maximum offset provided by the respective predetermined offsets between the development plane defined by the first outer edge and the reference plane defined by the second outer edge, preferably the increased thickness of the glenoid component is defined by a maximum offset equal to or greater than 15% of the diameter of the glenoid component, more preferably equal to or greater than 25%.
[0024] Preferably, the predetermined offset is configured to vary the longitudinal distance along the periphery of the first outer edge and the periphery of the second outer edge, thereby defining an angle between the development plane and the reference plane.
[0025] Advantageously, this solution makes it possible to re-establish the correct morphology in the presence of angular-type bone defects, especially in the posterior spherical glenoid surface.
[0026] More preferably, the angle between the development plane and the reference plane is comprised between 2 and 30 degrees, preferably between 5 and 25 degrees, and more preferably available in increments of 5 degrees.
[0027] Advantageously, this range is particularly effective for correcting typical bone defects of the angular type, without problems of mechanical resistance of the components and without the need for further milling operations.
[0028] According to an alternative embodiment, the predetermined offset is configured to maintain a substantially constant longitudinal distance along a parameter of the first outer edge and the second outer edge, wherein the unfolding plane and the reference plane are substantially parallel to each other in defining the standard increased thickness.
[0029] Advantageously, this alternative embodiment is particularly suited to central glenoid erosion, allowing for restoration of original thickness.
[0030] Preferably, the longitudinal distance is comprised between 2 and 10 mm, more preferably between 4 and 6 mm.
[0031] Advantageously, this range is particularly suited to typical central bone defects where proper tensioning of the soft tissue is still required.
[0032] Preferably, the glenoid component further includes a substantially frustoconical glenoid connecting element protruding from the glenoid connecting surface and adapted to connect to a bone pin, the glenoid connecting element extending along an axis that is substantially perpendicular to the reference plane.
[0033] Advantageously, this solution is suitable for association with bone pins of different lengths, making the glenoid component according to the invention suitable for a number of different solutions.
[0034] Further preferably, the first convex portion of the glenoid component presents a substantially constant radius of curvature preferably comprised between 25 and 35 mm, more preferably between 27 and 30 mm, while the second portion is preferably concave.
[0035] Advantageously, such configurations allow the radius of curvature of the original glenoid bone to be replicated in the best possible way, and the same instrumentation can be used for all configurations to obtain the correct seat for the glenoid component.
[0036] More preferably, the first outer edge of the glenoid joining surface is substantially circular or oval or glenoid shaped, while the second outer edge of the prosthetic joining surface is substantially circular or oval.
[0037] Advantageously, the circular configuration allows for continuous orientation of the glenoid component, covering all types of defects over 360 degrees.
[0038] The oval or glenoid configurations represent the optimum conditions for an anatomical prosthesis, where the humeral head articulates precisely anatomically on the glenoid surface. Indeed, these configurations are particularly suitable when the surgeon considers it necessary to use an anatomical prosthesis, for example in young patients with an intact rotator cuff.
[0039] More preferably, the glenoid component further comprises at least two holes, preferably four holes, adapted to receive the component's mounting screws.
[0040] Advantageously, the correct selection of the number of attachment screws allows for correct orientation of the components even in mixed bone defects.
[0041] Preferably, according to an alternative embodiment, said holes are adapted to receive respective angle locking screws.
[0042] More preferably, the predetermined offset comprises a first offset at the bore and a second offset at the glenoid joint element.
[0043] The first and second offsets are intended in a particularly advantageous embodiment to provide an additional thickness to the screw hole for the introduction of an angularly stable fixation element.
[0044] Preferably, the first offset includes a first threaded portion adapted to receive a circumferentially threaded closure element, and preferably, the second offset includes a second threaded portion adapted to receive a head of one of the angle locking screws.
[0045] Advantageously, the above solution leaves the surgeon with the possibility, in a first step, of introducing the angle-fixing screws and orienting them in the most suitable direction, and, in a second step, of fixing the inserted screws by inserting a closure element, regardless of the direction selected for the angle-fixing screws in the first step.
[0046] Preferably, the glenoid bonding surface includes a trabecular porous structure adapted to increase stability and osteointegration of the glenoid component.
[0047] More preferably, the glenoid component further includes a retention element protruding from the prosthesis bonding surface, said retention element preferably adapted to receive and retain an anatomical liner, preferably of polyethylene, that advantageously replicates the surface against which the humeral head articulates.
[0048] Preferably, the present invention provides a set including a plurality of glenoid components having different predetermined offsets to define different standard augmented thicknesses adapted to compensate for different bone defects. Advantageously, the glenoid components provide different standard augmented thicknesses, particularly in multiple discrete increments (i.e., 5%, or 7.5%, or 10% increases, or even different increments) that are available to the surgeon to appropriately compensate for the unique bone defects encountered by the patient.
[0049] According to a further aspect of the present invention there is provided a shoulder prosthesis including a glenoid component made in accordance with the above and at least one second prosthetic component.
[0050] Further features and advantages will become more apparent from the following detailed description of preferred, non-limiting embodiments of the invention and from the dependent claims which outline preferred and particularly advantageous embodiments of the invention. [Brief explanation of the drawings]
[0051] The invention will now be described with reference to the following figures, given as non-limiting examples. [Figure 1A] 1A-1D show front and rear perspective views of an embodiment of a glenoid component according to the present invention. [Figure 1B] 1A-1D show front and rear perspective views of an embodiment of a glenoid component according to the present invention. [Figure 2] 2 illustrates a possible connection between the glenoid component of FIG. 1 and a bone pin; [Figure 3A] 1C illustrates an exemplary attachment of the glenoid component of FIGS. 1A and 1B on the scapula. [Figure 3B] 1C illustrates an exemplary attachment of the glenoid component of FIGS. 1A and 1B on the scapula. [Figure 4] FIG. 1C shows a side view of the glenoid component of FIGS. 1A and 1B. [Figure 5] 1C illustrates possible variations of the glenoid component of FIGS. 1A and 1B. [Figure 6] 1C illustrates a further variation of the glenoid component of FIGS. 1A and 1B. [Figure 7] 1A and 1B combined with attachment screws. [Figure 8] 1 shows a second embodiment of a glenoid component according to the present invention. [Figure 9] 9 illustrates a side view of the glenoid component of FIG. 8. [Figure 10]1C shows an exploded view of an exemplary configuration of the glenoid portion of a reverse shoulder prosthesis including the glenoid component of FIGS. 1A and 1B. FIG. [Figure 11A] 10A-10C show front and rear perspective views of a further embodiment of a glenoid component according to the present invention; [Figure 11B] 10A-10C show front and rear perspective views of a further embodiment of a glenoid component according to the present invention; [Figure 12A] 11C and 11D show front and rear perspective views of a variation of the glenoid component of FIGS. 11A and 11B. [Figure 12B] 11C and 11D show front and rear perspective views of a variation of the glenoid component of FIGS. 11A and 11B. [Figure 13] 11A and 11B show possible variations of the glenoid component of FIG. [Figure 14] 11A and 11B illustrate possible connections between the glenoid component and an anatomic liner. [Figure 15] 11C shows an exploded view of a further exemplary configuration of the glenoid portion of a reverse shoulder prosthesis including the glenoid component of FIGS. 11A and 11B. FIG. [Figure 16A] 11C illustrates a further exemplary attachment of the glenoid component of FIGS. 11A and 11B onto the scapula. [Figure 16B] 11C illustrates a further exemplary attachment of the glenoid component of FIGS. 11A and 11B onto the scapula. [Figure 17] 10 shows a perspective view of a further embodiment of a glenoid component according to the present invention; FIG. [Figure 18] 18 shows a further perspective view of the variant of FIG. 17 coupled with a mounting screw. [Figure 19A] 18 shows a perspective view and a cross-sectional view of the variation of FIG. 17 coupled with a mounting screw. [Figure 19B] 18 shows a perspective view and a cross-sectional view of the variant of FIG. 17 coupled with a mounting screw. In these different figures, similar elements will be identified by similar reference numerals. DETAILED DESCRIPTION OF THE INVENTION
[0052] Referring to the accompanying drawings, the reference numeral 100 generally designates one embodiment of a glenoid component for a shoulder prosthesis made in accordance with the present invention.
[0053] 1 depicts one embodiment of a glenoid component 100 including a glenoid interface surface 101 adapted for attachment to a bone. The glenoid interface surface 101 has a first convex portion 102 including a first outer edge 103 that defines a development plane 104. The glenoid component 100 further includes a prosthesis interface surface 105 opposite the glenoid interface surface 101 and adapted to receive a second prosthesis component of a shoulder prosthesis. The second prosthesis component is preferably the humeral component of the shoulder prosthesis.
[0054] The prosthesis bonding surface 105 has a second portion 106 that includes a second outer edge 107 that defines a reference plane 108. The second portion 106 is preferably concave.
[0055] The glenoid component provides a predetermined offset 109 between the development plane 104 and the reference plane 108 .
[0056] Additionally, the glenoid component 100 includes a substantially frustoconical glenoid joining element 110 that protrudes from the glenoid joining surface 101. The glenoid joining element 110 may be integral to the body of the glenoid component 100 or may be removable.
[0057] As can be seen in Figure 2, the glenoid connection element 110 is adapted to connect to a bone pin 111. This connection is of a modular type, preferably a Morse gradient conical connection. This allows for the possibility of using bone pins 111 of various lengths based on the bone quality and the stability desired by the surgeon during surgery. As a result, the surgeon has maximum flexibility for use with the same glenoid component 100. The glenoid connection element 110 extends along an axis that is substantially perpendicular to the reference plane 108.
[0058] In this embodiment, the glenoid component 100 includes four through holes 112 adapted to receive mounting screws for the glenoid component 100. Corresponding to each hole 112 is a recess 113, preferably having a substantially parallelepiped section, in the glenoid joint surface 101. Furthermore, a circular recess 114 associated with the recesses 113 is preferably provided around the periphery of the glenoid joint element 110.
[0059] 3A and 3B show a possible exemplary application of the glenoid component 100 to the scapula. In this exemplary, non-limiting embodiment, both the first outer edge 103 of the glenoid articulating surface 101 and the second outer edge 107 of the prosthesis articulating surface 105 are substantially circular. This configuration allows for continuous orientation of the glenoid component 100, covering all types of defects over 360 degrees. Nothing precludes the use of different configurations. For example, a first outer edge 103 of the glenoid articulating surface 101 in a glenoid shape can be provided, which represents an optimal state for an anatomical prosthesis in which the humeral head articulates on the glenoid surface.
[0060] However, this exemplary solution is only suitable for reverse prostheses. By reverse prosthesis, we mean a prosthesis that does not rely on the action of the rotator cuff muscles but on the deltoid muscle. That is, it is a prosthesis in which the humeral head rests on the glenoid cavity of the scapula, which articulates on a spherical liner placed on the humerus using the lever arm of the deltoid muscle. This type of prosthesis is strictly used in patients with irreparable rotator cuff injuries, which result in loss of shoulder function and strength, and in which the rotator cuff muscles cannot be employed to enable the shoulder prosthesis to function.
[0061] 4 represents a side view of the glenoid component 100, in which the first convex portion 102 can be particularly seen. Preferably, said first portion 102 presents a substantially constant radius of curvature R, preferably comprised between 25 and 35 mm, more preferably between 27 and 30 mm. The above configuration allows the radius of curvature of the original glenoid bone to be replicated in the best possible way and allows the same instrumentation to be used for all configurations to obtain the correct seat for the glenoid component 100.
[0062] Furthermore, the embodiment depicted in FIG. 4 has a predetermined offset 109 that is configured to vary the longitudinal distance along the periphery of the first outer edge 103 and the periphery of the second outer edge 107, thereby defining an angle α between the unfolding plane 104 and the reference plane 108.
[0063] 5 shows different variations of the above embodiment. Considering the need to establish an appropriate correction in all cases, the different variations of the glenoid component 100 provide different inclinations of the unfolding plane 104 of the first convex portion 102, and thus different angles α, that should be considered based on the severity of the defect. It should be noted that even overcorrection relative to the neutral position (where the patient is in an upright position, the limb being examined is adducted laterally, and the palm is facing the side of the corresponding lower limb) can cause problems for the patient in the medium to long term.
[0064] As mentioned, the first portion 102 of the glenoid joint surface 101 is convex and has a constant radius of curvature R for all configurations using the same instrument, which in this case is represented by a cutter with the same radius of curvature. Therefore, it is sufficient to orient the cutter in the correct manner based on the defect. In particular, FIG. 5 depicts variations with angles from 0 to 25 degrees in 5-degree increments. Obviously, the above representations are merely exemplary and do not limit the scope of protection defined in the appended claims. This example was chosen because the depicted angles are the most frequently encountered, and a 5-degree increment between one variation and the other is considered the smallest perceptible. However, as mentioned, the glenoid component 100 can be fabricated with all possible intermediate angles, such as 17.5- or 12-degree angles, based on the surgeon's specific needs. For glenoid components 100 with greater angulation, longer bone pins 111 are used because the additional material covers part of the exposed surface of the pin.
[0065] Preferably, the glenoid component 100 is not fabricated at an angle greater than 30 degrees, preferably no greater than 25 degrees, to avoid mechanical strength problems of the glenoid component 100 that increase the lever arm between the point of application of force and the bone. Generally, to correct very severe defects, such as a 35-degree angle, it is preferable to use a glenoid component 100 combined with a preliminary milling operation on an inclined axis to the eroded surface. However, nothing prevents the provision of a more durable glenoid component 100 and the use of a higher angle for the development plane 104.
[0066] Additionally, the increased thickness of the glenoid component shown in FIG. 5 is defined by a maximum offset between the glenoid and prosthetic interface surfaces ranging from approximately 10% at 0 degrees, approximately 20% at 5 degrees, approximately 25% at 10 degrees, approximately 33% at 25 degrees, approximately 43% at 20 degrees, and approximately 50% at 25 degrees relative to the respective diameters of the glenoid component.
[0067] The location of the center of convex curvature of the glenoid component 100 is selected in various configurations to ensure the desired angle α while also ensuring a minimum thickness of the glenoid component 100 and to avoid any mechanical sealing issues.
[0068] In this case having the first circular outer edge 103 and the second circular outer edge 107, it is sufficient to position the thickest part of the glenoid component 100 along the direction of the bone defect.
[0069] 6 further depicts a variation 600 of the glenoid component 100 in which a porous / trabecular structure 601 is provided on the glenoid bonding surface 101 to increase stability and osseointegration of the glenoid component 100 in bone. The trabecular structure is a structure that incorporates that property of bone tissue, in which lamellae are arranged to form interconnecting cavities.
[0070] 7, the glenoid component 100, in this embodiment, has four holes 112 adapted to receive attachment screws 715 relative to the bone surface. In the above embodiment, these four holes 112 allow for the selection of the location and optimal number of attachment screws 715 for attachment, even when the glenoid component 100 is oriented along a mixed defect, for example, a 45-degree inclined inferior-posterior defect.
[0071] FIG. 8 shows a different embodiment 800 in different variations. In this embodiment, the predetermined offset 809 is configured to maintain a substantially constant longitudinal distance along the circumference of the first outer edge 803 and the circumference of the second outer edge 807. Here, the development plane 104 and the reference plane 108 are substantially parallel to each other. This embodiment is particularly suitable for cases of central glenoid erosion. Indeed, under this condition, the glenoid component 800 requires an axial milling operation to remove the missing portion. By increasing it in terms of its planar thickness rather than angularly, the milled glenoid surface returns to the same original height. The variants depicted in FIG. 8 differ from each other in that the thickness S is different.
[0072] The glenoid joint surface 801, as seen in FIG. 9, again has a first convex portion 802 with a constant radius of curvature R. The center of the convex curvature is always axial with the glenoid component 800 in this case. Therefore, in the preparation stage, a sheet for the glenoid component 800 is made with a cutting tool having the same radius R. This sheet is placed coaxially and worked until the central defect is removed. In addition to its use to compensate for central bone defects, this embodiment is also suitable for correctly tensioning the soft tissue. Preferably, this embodiment is made with a thickness that is not too large to avoid drawbacks of the mechanical seal.
[0073] Further, the increased thickness of the glenoid component shown in FIG. 8 is defined by a maximum offset provided by each predetermined offset 809 between the development plane defined by the first outer edge 803 and the reference plane defined by the second outer edge ranging from about 9%, about 18%, and about 25% of the respective diameter of the glenoid component.
[0074] In that regard, a "normal" thickness of the glenoid component is defined by an offset of approximately 9% of the diameter of the glenoid component, while an increased thickness of the glenoid component is defined by a larger offset, preferably greater than 15%, and more preferably greater than 25%, as also illustrated with reference to FIG. 5 above.
[0075] Preferably, the longitudinal distance is comprised between 2 and 10 mm, more preferably between 4 and 6 mm.
[0076] However, nothing prevents the use of more resistant components of different thicknesses, which fall within the scope of protection defined in the appended claims.
[0077] FIG. 10 depicts an exploded view of an exemplary configuration of the glenoid portion of a reverse shoulder prosthesis having a glenoid component 100 including a glenoid connection element 110 and joined with a mounting screw 715, a bone pin 111, and a prosthetic hemisphere 116.
[0078] In cases where the surgeon deems it necessary to use an anatomical prosthesis rather than a reverse prosthesis, for example in the case of a young patient with an intact rotator cuff, a further embodiment of the glenoid component 1000 is provided, represented in two different variants in Figures 11A and 11B and Figures 12A and 12B.
[0079] In particular, Figures 11A and 11B show an inferior-superior bone defect (IS) configuration, while Figures 12A and 12B show an anterior-posterior bone defect (AP) configuration.
[0080] As can be seen, this embodiment in both variations shown provides both a first outer edge 1003 of the glenoid joining surface 1001 and a second outer edge 1007 of the prosthesis joining surface 1005 that is substantially elliptical. The two variations are necessary because, as with the embodiment having circular outer edges 103 and 107, the glenoid component 1000 cannot be rotated due to asymmetry issues.
[0081] This is an anatomical prosthesis. Therefore, the glenoid component 1000 must be positioned vertically on the glenoid cavity to anatomically recreate the surface. Therefore, in the case of a mixed defect, e.g., an upper-posterior defect with a 45-degree inclination, one of two positions, i.e., posterior or superior, must be selected and a seat must be created by milling until the defect is eliminated. However, alternatively, a dedicated glenoid component 1000 for a specific bone defect can be deployed.
[0082] Even in this embodiment, the glenoid component 1000 includes a substantially frustoconical glenoid attachment element 1010 that protrudes from the glenoid attachment surface 1001 and is adapted to attach to a bone pin 1111, the glenoid attachment element 1010 extending along an axis that is substantially perpendicular to the reference plane 1008. Even in this embodiment, bone pins 1111 of various lengths can be modularly attached. Because the geometry of the glenoid attachment element 1000 is similar, the same glenoid component can be employed in both the reverse configuration and the anatomical prosthetic case. This is particularly useful when a conversion is required, i.e., when a transition to a reverse implant is required after initial anatomical implantation.
[0083] The glenoid component 1000, as can be seen in Figure 13, offers the same features as the previous embodiment. In particular, a variant is seen having a predetermined offset 1009 which varies in longitudinal distance along the periphery of the first outer edge 1003 and the periphery of the second outer edge 1007 and is configured to define an angle α between the unfolding plane 1004 and the reference plane 1008. Even in this case, a range of angle α comprised between 5 and 25 degrees is preferred, although nothing prevents different angles from being employed.
[0084] In the case of central erosion, a further variant can be found with a predetermined offset 1009 configured to maintain a substantially constant longitudinal distance along the periphery of the first outer edge 1003 and along the periphery of the second outer edge 1007. Even in this case, a range of longitudinal distances comprised between 4 mm and 6 mm is preferred, although nothing prevents the provision of different longitudinal distances.
[0085] In all cases, a constant radius of curvature R is provided, with the same characteristics regarding the convex center of curvature as described for the corresponding embodiment above.
[0086] A retaining element 1110 is preferably further provided which protrudes from the prosthesis bonding surface 1001 .
[0087] The retaining element 1110 is preferably adapted to receive and retain an anatomical liner 1113, as seen in FIG. 14, i.e., a coating that replicates the surface against which the humeral head will articulate. The element protects and reduces impacts and allows for coupling between the humeral head and the glenoid cavity. Preferably, the anatomical liner 1111 is made of polyethylene. It can further be seen in FIG. 14 that this embodiment, given its particular configuration, allows for the use of two attachment screws 1115 and thus provides only two holes 1112.
[0088] FIG. 15 shows an exploded view of an exemplary configuration of the glenoid portion of a reverse shoulder prosthesis having a glenoid component 1000 including a glenoid connection element 1010 and joined with a mounting screw 1115, a bone pin 1111, and a prosthetic hemisphere 1116.
[0089] 16A and 16B show possible exemplary applications of glenoid component 1000 to the scapula. Glenoid component 1000 can be fabricated in various length and width dimensions to replicate the correct geometry of the glenoid for anatomical implantation, and as a result, different sized anatomical liners can be employed.
[0090] If the surgeon provides for the use of angle locking screws, an alternative embodiment 1200 is further provided, as depicted in Figures 17, 18, 19A, and 19B, in which the holes 112 are adapted to receive respective angle locking screws 1201.
[0091] According to the above embodiment, the predetermined offset 109 on the prosthesis joining surface 105 of the glenoid component 1200 comprises a first offset 109A on the bore 112 and a second offset 109B on the glenoid joining element 110. The first offset 109A is preferably comprised between 1 mm and 7 mm, and even more preferably between 2 mm and 4 mm. It is observed that in this embodiment, the first offset 109A represents an additional thickness, while the second offset 109B substantially corresponds to the overall thickness 109 of the other previously described embodiments. The first offset 109A consequently serves as an additional thickness, allowing the introduction of a fixation element for the angle locking screw 1201.
[0092] The portion of the glenoid component 1200 including the glenoid joint element 110 remains unchanged by not introducing any lateralization, while the glenoid component 100 provides an offset in the hole 112 that is configured to provide space for polyaxial fixation of the screw 1201.
[0093] 19B, the first offset 109A includes a first threaded portion 1202 that, in this embodiment, is adapted to receive a circumferentially threaded closure element 1203. The circumferentially threaded closure element 1203 is similar to a threaded cover and locking cap for the screw 1201.
[0094] The second offset 109B comprises a second threaded portion 1204 adapted to receive the head 1205 of one of the angle locking screws 1201. In the embodiment shown, these figures particularly represent a hemispherical head of the screw 1201 having a hexagonal recess into which an associated circumferentially threaded closure element 1203 is inserted, said embodiment being, as stated, exemplary and non-limiting.
[0095] Specifically, the mounting screw 1201 is oriented and threaded in the same manner as in the previous embodiment, while the closure element 1203 allows for its angular fixation once introduced. The closure element 1203 is consequently threaded onto the head of the angle fixation screw 1201, compressing and fixing it polyaxially. Obviously, this solution may be applied to all holes 112 or to some of them.
[0096] In a variant, nothing prevents the provision of a second offset 109B without threads and only the first offset 109A with threads, particularly if the angle desired for the screw 1201 and the angle at which the majority of the screw 1201 projects is not particularly emphasized.
[0097] Furthermore, further variants with different fixation solutions can be provided, for example, by employing a mounting screw with an oversized head that includes an expandable elastic element, in which case polyaxial fixation of the screw 1201 can be obtained by expanding the elastic element within the first offset 109A, without the latter having to provide a threaded portion.
[0098] The present invention further provides at least one shoulder prosthesis including a glenoid component according to one of the embodiments and variations of the present invention and at least one associated prosthetic component associated with the glenoid component, such as, for example, the anatomical liner 1113 described above.
[0099] Advantageously, the present invention allows a variety of possibilities in correcting bone defects using standard and tested components suited to the patient's unique clinical situation.
[0100] Furthermore, the present invention allows the surgeon to employ a single instrument during the preparation stage, combining specificity under different conditions with different characteristics related to the inherent bone defect with universality of use by providing a surface that is specifically adapted to bond on a convex glenoid cavity having a constant radius.
[0101] Advantageously, the present invention is suitable for different conditions of bone defects, whether due to corner or central erosion.
[0102] Advantageously, the present invention allows for the optimization of time and precision of shoulder-specific surgical procedures.
[0103] Further advantageously, the present invention provides a relatively simple and intuitive application for the surgeon.
[0104] Further advantageously, the present invention provides for coupling with existing devices such as bone pins, and even allows for coupling with several bone pins of various lengths with a single glenoid component.
[0105] Finally, advantageously, the invention does not have particularly complex structural characteristics and is suitable for mass production, which has clear implications from an economic point of view.
[0106] It should also be noted that each of these different embodiments further offers unique and distinctive advantages as described.
[0107] It is apparent that specific element configurations described with reference to a particular embodiment can be used in other embodiments described herein, unless there is a technical contradiction apparent to one skilled in the art.
[0108] For example, the trabecular porous structure 601 can be used even in embodiments having an elliptical peripheral structure.
[0109] Therefore, the embodiments described herein should be understood as illustrative and non-limiting examples of the present invention. (Other possible items) (Item 1) A glenoid component (100, 600, 800, 1000, 1200) for a shoulder prosthesis, comprising: a glenoid joint surface (101, 1001) adapted for attachment to bone and having a first convex portion (102) including a first outer edge (103, 1003) defining a development plane (104, 1004); a prosthesis interface surface (105, 1005) opposite the glenoid interface surface (101, 1001) and adapted to receive a second prosthesis component of the shoulder prosthesis, the prosthesis interface surface (105, 1005) having a second portion (106) including a second outer edge (107, 1007) that defines a reference plane (108, 1008); Equipped with The glenoid component (100, 1000) provides a predetermined offset (109, 809, 1009) between the development plane (104, 1004) and the reference plane (108, 1008), thereby defining an increased thickness of the glenoid component (100, 1000) adapted to compensate for bone defects. Glenoid components (100, 600, 800, 1000, 1200). (Item 2) 2. The glenoid component (100, 600, 800, 1000, 1200) according to item 1, wherein the predetermined offset (109, 809, 1009) varies in longitudinal distance along the circumference of the first outer edge (103, 1003) and the circumference of the second outer edge (107, 1007) and is configured to define an angle (α) between the unfolding plane (104, 1004) and the reference plane (108, 1008). (Item 3) 3. The glenoid component (100, 600, 800, 1000, 1200) according to item 2, wherein said angle (α) is comprised between 2 degrees and 30 degrees, preferably comprised between 5 degrees and 25 degrees, and more preferably is available in increments of 5 degrees. (Item 4) 2. The glenoid component (100, 600, 800, 1000, 1200) according to item 1, wherein the predetermined offset (109, 809, 1009) is configured to maintain a substantially constant longitudinal distance along the outer periphery of the first outer edge (103, 1003) and the outer periphery of the second outer edge (107, 1007), and wherein the unfolding plane (104, 1004) and the reference plane (108, 1008) are substantially parallel to each other. (Item 5) 5. The glenoid component (100, 600, 800, 1000, 1200) according to item 4, wherein said longitudinal distance is comprised between 2 mm and 10 mm, more preferably comprised between 4 mm and 6 mm. (Item 6) 6. The glenoid component (100, 600, 800, 1000, 1200) according to any one of items 1 to 5, further comprising a substantially frustoconical glenoid connection element (110, 1010) protruding from the glenoid connection surface (101, 1001) and adapted to connect to a bone pin (111, 1111) of the shoulder prosthesis, the glenoid connection element (110, 1010) extending along an axis that is substantially perpendicular to the reference plane (108, 1008). (Item 7) 7. The glenoid component (100, 600, 800, 1000, 1200) according to any one of items 1 to 6, wherein the first convex portion (102) presents a substantially constant radius of curvature (R) preferably comprised between 25 mm and 35 mm, more preferably between 27 mm and 30 mm, and the second portion (106) is preferably concave. (Item 8) 8. The glenoid component (100, 600, 800, 1000, 1200) according to any one of items 1 to 7, wherein the first outer edge (103, 1003) of the glenoid joining surface (101, 1001) is substantially circular or elliptical or glenoid-shaped. (Item 9) 9. The glenoid component (100, 600, 800, 1000, 1200) according to any one of items 1 to 8, wherein the second outer edge (107, 1007) of the prosthesis joining surface (105, 1005) is substantially circular or elliptical. (Item 10) 10. The glenoid component (100, 600, 800, 1000, 1200) according to any one of items 1 to 9, further comprising at least two holes (112, 1112), preferably four holes (112, 1112), adapted to receive mounting screws (715, 1115) of the glenoid component of the shoulder prosthesis. (Item 11) Item 11. The glenoid component (100, 600, 800, 1000, 1200) according to item 10, wherein said holes (112, 1112) are adapted to receive respective angle locking screws (1201). (Item 12) Item 12. The glenoid component (100, 600, 800, 1000, 1200) according to item 11, wherein the predetermined offset (109, 809, 1009) comprises a first offset (109A) in the hole (112, 1112) and a second offset (109B) in the glenoid joint element (110, 1010). (Item 13) Item 13. The glenoid component (100, 600, 800, 1000, 1200) according to item 12, wherein the first offset (109A) comprises a first threaded portion adapted to accommodate a circumferentially threaded closure element (1203), and preferably the second offset (109B) comprises a second threaded portion adapted to accommodate a head (1205) of a respective angular locking screw (1201). (Item 14) 14. The glenoid component (100, 600, 800, 1000, 1200) according to any one of items 1 to 13, wherein the glenoid joint surface (101, 1001) has a trabecular porous structure (601) adapted to increase stability and bone integration of the glenoid component (100, 1000). (Item 15) A glenoid component (100, 600, 800, 1000, 1200) according to any one of items 1 to 14, further comprising a retention element (1110) protruding from the prosthesis bonding surface, preferably the retention element (1110) being adapted to receive and retain an anatomical liner (1113). (Item 16) 16. The glenoid component (100, 600, 800, 1000, 1200) of any one of items 1 to 15, wherein a set of said glenoid components (100, 600, 800, 1000, 1200) provide respective different predetermined offsets (109, 809, 1009) thereby defining a plurality of different standard increased thicknesses adapted to compensate for different bone defects. (Item 17) 17. A set of glenoid components (100, 600, 800, 1000, 1200) according to any one of items 1 to 16, wherein each glenoid component of the set defines a plurality of standard increased thicknesses adapted to compensate for different bone defects by providing a respective predetermined offset (109, 809, 1009). (Item 18) 17. A glenoid component (100, 600, 800, 1000, 1200) according to any one of items 1 to 16, at least one second prosthetic component (1010, 1116, 1113) connected to said glenoid component (100, 600, 800, 1000, 1200); A shoulder prosthesis comprising:
Claims
1. 1. A glenoid component for a shoulder prosthesis, comprising: a glenoid joint surface adapted for attachment to bone and having a first convex portion including a first outer edge defining a development plane; a prosthesis interface surface opposite the glenoid interface surface and adapted to receive a second prosthesis component of the shoulder prosthesis, the prosthesis interface surface having a second portion including a second outer edge defining a reference plane; a substantially frustoconical glenoid connecting element protruding from the glenoid connecting surface and adapted to connect to a bone pin of the shoulder prosthesis, the glenoid connecting element extending along an axis that is substantially perpendicular to the reference plane; Equipped with the glenoid component is configured to provide a predetermined offset between the unfolded plane and the reference plane, the predetermined offset varying in longitudinal distance along a circumference of the first outer edge and a circumference of the second outer edge and defining an angle between the unfolded plane and the reference plane, the predetermined offset defining an increased thickness of the glenoid component to compensate for a bone defect; the first outer edge of the glenoid joining surface is substantially circular and the second outer edge of the prosthesis joining surface is substantially circular, thereby allowing continuous orientation of the glenoid component and covering all types of bone defects over 360 degrees; Glenoid component.
2. The glenoid component of claim 1 , wherein the angle is comprised between 2 and 30 degrees, preferably between 5 and 25 degrees, and more preferably available in 5 degree increments.
3. 3. The glenoid component according to claim 1 or 2, wherein the first convex portion presents a substantially constant radius of curvature preferably comprised between 25 mm and 35 mm, more preferably between 27 mm and 30 mm, and the second portion is preferably concave.
4. 4. A glenoid component according to any one of claims 1 to 3, further comprising at least two holes, preferably four holes adapted to receive mounting screws of the glenoid component of the shoulder prosthesis.
5. The glenoid component of claim 4 , wherein the holes are adapted to receive respective angle locking screws.
6. The glenoid component of claim 5 , wherein the predetermined offset comprises a first offset at the bore and a second offset at the glenoid joining element.
7. 7. The glenoid component according to claim 6, wherein the first offset includes a first threaded portion adapted to receive a circumferentially threaded closure element, and preferably the second offset includes a second threaded portion adapted to receive a head of a respective angular locking screw.
8. The glenoid component of claim 1 , wherein the glenoid bonding surface has a trabecular porous structure adapted to increase stability and osteointegration of the glenoid component.
9. 9. The glenoid component of claim 1, further comprising a retention element protruding from the prosthesis bonding surface, preferably the retention element adapted to receive and retain an anatomical liner.
10. 10. The glenoid component of claim 1, wherein a set of said glenoid components provide respective different predetermined offsets to define a plurality of different standard increased thicknesses to compensate for different bone defects.
11. 11. A set of glenoid components according to any one of claims 1 to 10, wherein each glenoid component of the set provides a respective predetermined offset to define a plurality of standard increased thicknesses to compensate for different bone defects.
12. A glenoid component according to any one of claims 1 to 10; at least one second prosthetic component connected to the glenoid component; A shoulder prosthesis comprising: