Humeral head-troch adapter and method of installing same

Abstract

The present disclosure provides a humeral head-tuberosity adapter and its installation method, comprising an adapter body, the adapter body is formed with a tuberosity side surface and a bone side surface; the bone side surface is provided with a fixing column extending away from the adapter body; the inner concave arc-shaped bone side surface of the adapter body is combined with the humeral head bone surface, which can expand the load transmission area and disperse the local compressive stress; the outer convex arc-shaped tuberosity side surface forms a sliding support interface with the tuberosity surface, so that the contact load generated by the shoulder joint movement is transmitted along the arc surface, which is beneficial to limit the upward movement of the humeral head and maintain the distance between the tuberosity and the humeral head; the fixing column is inserted into the humeral head to form axial anchoring, and the triangular anti-rotation piece extends from the outer periphery of the fixing column to the bone side surface, which can transmit the tangential force and eccentric load to the humeral head; the adapter body, the fixing column and the anti-rotation piece are integrally formed, which reduces the risk of loosening or breaking at the connection position, so as to balance the implant stability and long-term support effect.

Description

Technical Field

[0001] This disclosure relates to the field of medical device technology, and more specifically, to a humeral head acromion adapter and its installation method. Background Technology

[0002] The shoulder joint is mainly composed of the humeral head, glenoid fossa, acromion, and rotator cuff. The acromion is located above the humeral head, and the rotator cuff tendons wrap around the humeral head, maintaining the relative position between the humeral head and glenoid fossa during shoulder joint movement. After a large or irreparable rotator cuff injury, the restraining effect of the rotator cuff on the humeral head weakens, making the humeral head more prone to displacement towards the acromion. This reduces the gap between the humeral head and the acromion, thus affecting the stability and range of motion of the shoulder joint.

[0003] To address the above situation, existing technologies typically employ methods such as subacromial spacers, soft tissue reconstruction, or shoulder replacement. Subacromial spacers are generally placed between the humeral head and the acromion to maintain the distance between them; soft tissue reconstruction usually involves using grafts to rebuild the soft tissue constraints above the shoulder joint; and shoulder replacement improves the functional impairment caused by superior displacement of the humeral head by altering the joint structure and stress relationships of the shoulder joint.

[0004] However, the shoulder joint experiences continuously changing compressive forces, tangential forces, and eccentric loads during movement. Existing subacromial spacers are prone to positional changes, morphological alterations, or decreased support capacity after prolonged stress, making it difficult to maintain a stable relationship between the humeral head and the acromion. Soft tissue reconstruction places high demands on graft quality and healing, while shoulder replacement surgery involves relatively significant surgical trauma and alterations to the original bony structure. Therefore, current techniques still face the challenge of simultaneously achieving implant stability, long-term support, and preservation of the original shoulder joint structure. Summary of the Invention

[0005] The main objective of this disclosure is to provide a humeral head acromion adapter and its installation method, aiming to solve the technical problem mentioned in the background art that existing subacromial spacers are difficult to balance implantation stability and long-term support effects.

[0006] The present invention adopts the following technical solution: A humeral head acromion adapter and its installation method, comprising an adapter body, wherein the adapter body is arc-shaped and has an acromion-side surface and a bone-side surface, wherein the acromion-side surface and the bone-side surface are disposed opposite to each other; The bony side surface is provided with a fixation post extending away from the adapter body. An anti-rotation plate is provided on the outer periphery of the fixation post. The anti-rotation plate extends in a triangular shape along the outer periphery of the fixation post to the bony side surface. The acromion side surface is an outwardly convex arc surface, and the bony side surface is an inwardly concave arc surface. The adapter body, the fixation post and the anti-rotation plate are integrally formed.

[0007] Furthermore, the outer periphery of the fixation post is provided with a plurality of recessed grooves, the recessed grooves extend along the axial direction of the fixation post, the plurality of recessed grooves are arranged in a circumferential array around the axis of the fixation post, one end of the recessed groove extends to the bone side surface, and the other end of the recessed groove is distributed between the end of the fixation post away from the adapter body and the anti-rotation plate, for embedding and installation of bone cement.

[0008] Furthermore, the anti-rotation plate includes a first anti-rotation portion and a second anti-rotation portion, which are symmetrically distributed on opposite sides of the fixed column along the axis of the fixed column.

[0009] Furthermore, an arc-shaped transition portion is provided at the connection between the first anti-rotation portion and the bone side surface and the fixation post, as well as at the connection between the second anti-rotation portion and the bone side surface and the fixation post.

[0010] Furthermore, the length of the first anti-rotation portion extending along the axial direction of the fixing post is greater than the length of the second anti-rotation portion extending along the axial direction of the fixing post, and the lengths of both the first and second anti-rotation portions extending along the axial direction of the fixing post are less than the length of the fixing post extending away from the adapter body.

[0011] Furthermore, the fixation post is a long column or a short column. The fixation post includes a main body and a bottom end disposed at the end of the main body away from the bone side surface. The main body is cylindrical or conical, and the bottom end is spherical or truncated conical. When the fixation post is conical, the diameter of the fixation post gradually decreases in the direction away from the bone side surface.

[0012] Furthermore, the axis of the fixation post passes through the center of curvature of the bone side surface.

[0013] Furthermore, the surface of the antirotation plate is provided with an array of longitudinal grooves or a rough surface, and the bone side surface is provided with a bone bonding layer, which is one of a porous titanium coating, a rough layer, or a biological coating.

[0014] Furthermore, the adapter body, fixing post, and anti-rotation plate are all integrally molded from one of the following materials: PEEK material, carbon fiber reinforced PEEK material, PEKK material, or medical polymer composite material.

[0015] A method for installing a humeral head acromion adapter, using the humeral head acromion adapter as described in any of the preceding claims, comprising: S1. Provide a mounting base, drill holes in the mounting base according to the shape of the fixing column to form mounting holes, and cut the edges of the mounting holes according to the shape of the anti-rotation plate to form mounting grooves. S2. Based on the gap between the fixing post and the mounting hole and between the anti-rotation plate and the mounting groove, inject bone cement in a measured amount into the mounting hole and / or mounting groove; S3. When the bone cement is in a plastic state, press the fixation post and the anti-rotation plate into the mounting hole and mounting groove respectively, so that the bone cement is distributed between the wall of the fixation post and the wall of the mounting hole and / or between the anti-rotation plate and the wall of the mounting groove. During the pressing process, prevent the bone cement from overflowing to the bone side surface. S4. Maintain the position of the adapter body relative to the mounting base, so that the bone side surface is in contact with the surface of the mounting base and the acromion side surface is facing away from the mounting base, until the bone cement hardens to form a fixed structure.

[0016] Beneficial effects: In this invention, the concave arc-shaped bony side surface of the adapter body fits against the humeral head bone surface, which expands the load transfer area and disperses local compressive stress. The convex arc-shaped acromion side surface and the acromion underside surface form a suitable sliding support interface, allowing the contact load generated by shoulder joint movement to be transferred along the arc surface, which helps to limit the upward movement of the humeral head and maintain the distance between the acromion and the humeral head. The fixation post is inserted into the humeral head to form axial anchorage, and the triangular anti-rotation plate extends from the outer periphery of the fixation post to the bony side surface, which can transfer tangential force and eccentric load to the humeral head and improve anti-rotation and anti-swing capabilities, and reduce micro-movements at the bone contact interface. The adapter body, fixation post and anti-rotation plate are integrally molded, which can ensure the continuity of load transfer and reduce the risk of loosening or breakage at the connection position, thus taking into account both implantation stability and long-term support effect. In addition, the integral molding is carried out by injection molding in one step, which can greatly improve production efficiency compared to the hours or even days of existing machining. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of a humeral head acromion adapter according to the present invention; Figure 2 This is a bottom view of the acromion adapter for the humeral head according to the present invention; Figure 3 This is a front view structural diagram of an acromion adapter for the humeral head according to the present invention; Figure 4 This is a schematic cross-sectional view of the present invention along the axis of the fixed column; in: 1. Adapter body; 11. Acromion side surface; 12. Bone side surface; 2. Fixation post; 21. Recessed groove; 22. Main body; 23. Bottom end; 3. Anti-rotation plate; 31. First anti-rotation part; 32. Second anti-rotation part; 4. Arc-shaped transition part.

[0018] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0020] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0022] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0023] Reference Figures 1 to 4 The present invention proposes a humeral head acromion adapter, including an adapter body 1, wherein the adapter body 1 is formed in an arc shape with an acromion side surface 11 and a bone side surface 12, and the acromion side surface 11 and the bone side surface 12 are arranged opposite to each other. The bony side surface 12 is provided with a fixation post 2 extending away from the adapter body 1. An anti-rotation plate 3 is provided on the outer periphery of the fixation post 2. The anti-rotation plate 3 extends in a triangular shape along the outer periphery of the fixation post 2 to the bony side surface 12. The acromion side surface 11 is an outwardly convex arc surface, and the bony side surface 12 is an inwardly concave arc surface. The adapter body 1, the fixation post 2 and the anti-rotation plate 3 are integrally formed.

[0024] In the above embodiments, this embodiment provides a humeral head acromion adapter, including an adapter body 1 in the shape of an arcuate plate. The adapter body 1 has an acromion-side surface 11 and a bone-side surface 12 disposed opposite to each other along its thickness direction. The names of the two surfaces are determined by their orientation after implantation. The acromion-side surface 11 faces the inferior surface of the acromion and forms an outwardly convex arcuate surface, while the bone-side surface 12 faces the bone surface of the humeral head and forms an inwardly concave arcuate surface. The contour of the inwardly concave arcuate surface is adapted to the contour of the bone surface of the humeral head implantation area, so that the adapter body 1 can cover and conform to the bone surface of the humeral head. The load transmitted from the acromion to the adapter body 1 can be distributed to the corresponding bone surface through the bone-side surface 12, avoiding the load being concentrated only in a small connection area. The outwardly convex arcuate surface forms a continuous support contour. When it contacts the inferior surface of the acromion during shoulder joint movement, the contact position can change along the arcuate surface with the relative movement of the two, thus being able to withstand the load from the acromion direction in different movement positions and providing continuous support to the humeral head through the adapter body 1.

[0025] The bony surface 12 is provided with a fixation post 2 extending away from the adapter body 1. The fixation post 2 is used to insert into a pre-formed mounting hole on the humeral head, thereby restricting the translation of the adapter body 1 along the bone surface and bearing the pull-out load acting along the axial direction of the fixation post 2. An anti-rotation plate 3 is provided on the outer periphery of the fixation post 2. The anti-rotation plate 3 is a sheet-like structure extending from the fixation post 2 to the bony surface 12. In this embodiment, the triangular extension means that the lateral contour of the anti-rotation plate 3 is defined by the post side connecting the outer periphery of the fixation post 2, the body side connecting the bony surface 12, and the inclined side located between the two. When the adapter is implanted, the anti-rotation plate 3 is embedded in the mounting area on the humeral head corresponding to its shape. When the acromial side surface 11 is subjected to tangential force or eccentric load, the load will cause the adapter body 1 to tend to rotate about the axis of the fixation post 2 or swing relative to the bone surface; the anti-rotation plate 3 forms a circumferential constraint with the surrounding bone tissue and uses its radial extension distance relative to the axis of the fixation post 2 to bear the rotational load, thereby reducing the relative rotation between the fixation post 2 and the mounting hole. The anti-rotation plate 3 forms a wider connection area near the bone side surface 12, which can gradually transfer the load borne by the adapter body 1 to the fixation post 2, reducing the local stress at the connection root. The adapter body 1, fixation post 2 and anti-rotation plate 3 are integrally molded, and there is no detachable connection interface between the three, so that the support load can be transferred along the continuous structure, thereby improving the anti-rotation, anti-sway and structural load-bearing capacity after implantation, taking into account both installation stability and long-term support performance.

[0026] In one embodiment, a plurality of recessed grooves 21 are provided on the outer peripheral side of the fixation post 2. The recessed grooves 21 extend along the axial direction of the fixation post 2. The plurality of recessed grooves 21 are arranged in a circumferential array around the axis of the fixation post 2. One end of the recessed groove 21 extends to the bone side surface 12, and the other end of the recessed groove 21 is distributed between the end of the fixation post 2 away from the adapter body 1 and the anti-rotation plate 3, for embedding and installing bone cement.

[0027] In the above embodiment, a plurality of recessed grooves 21 are formed on the outer periphery of the fixation post 2, which are recessed into the post body. The length direction of each recessed groove 21 is consistent with the axial direction of the fixation post 2, and they are arranged circumferentially with the axis of the fixation post 2 as the center. One end of the recessed groove 21 near the adapter body 1 extends to the bone side surface 12, and the other end terminates in the post body area between the distal end of the fixation post 2 and the anti-rotation plate 3, that is, the recessed groove 21 does not penetrate the end of the fixation post 2 away from the adapter body 1. During installation, bone cement can enter the recessed groove 21 and form an interlocking structure extending along the axial direction of the fixation post 2 after curing. When the adapter is subjected to tensile load or rotational load, the cured bone cement abuts against the groove wall of the recessed groove 21, so that the load is no longer borne solely by the interface between the circumferential surface of the fixation post 2 and the bone cement. Several recessed grooves 21 are distributed in a circumferential array, which can make the bone cement form a relatively uniform connection area around the fixation post 2, reducing the deviation caused by insufficient connection on one side; since the recessed grooves 21 do not extend to the distal end of the fixation post 2, the structural continuity of the distal post can be preserved, avoiding excessive weakening of the integrity of the end of the fixation post 2 by the slotting, thereby improving the fixation post 2's ability to resist axial loosening and circumferential rotation.

[0028] In one example, the anti-rotation plate 3 includes a first anti-rotation portion 31 and a second anti-rotation portion 32, which are symmetrically distributed on opposite sides of the fixed post 2 along the axis of the fixed post 2.

[0029] In the above embodiment, the anti-rotation plate 3 includes a first anti-rotation portion 31 and a second anti-rotation portion 32, which are respectively disposed on opposite radial sides of the fixation post 2 with the axis of the fixation post 2 as the position reference, and extend from the outer periphery of the fixation post 2 to the bony surface 12. After the adapter is installed on the humeral head, the fixation post 2 constitutes the main intraosseous anchoring structure, and the first anti-rotation portion 31 and the second anti-rotation portion 32 are respectively embedded in the corresponding bony mounting areas on both sides of the fixation post 2. When the acromial side surface 11 is subjected to a tangential load with changing direction, the adapter body 1 may tend to rotate around the axis of the fixation post 2. The anti-rotation portion located on the front side in the direction of rotation abuts against the adjacent bone tissue and bears compressive stress, while the other anti-rotation portion restricts the adapter from further deflection from the opposite side.

[0030] Two anti-rotation parts are symmetrically distributed on opposite sides of the fixation post 2, so that the anti-rotation constraint is not concentrated on one side of the fixation post 2, and the resistance torque that the adapter needs to overcome when it rotates around the fixation post 2 in the circumferential direction is increased. At the same time, the double-sided structure can form opposite constraints on the swing of the adapter body 1, reduce the possibility of local warping of the bone side surface 12 and repeated swaying of the fixation post 2 in the mounting hole, thereby maintaining the relative position between the adapter and the humeral head.

[0031] In one example, an arc-shaped transition portion 4 is provided at the connection between the first anti-rotation portion 31 and the bone side surface 12 and the fixation post 2, as well as at the connection between the second anti-rotation portion 32 and the bone side surface 12 and the fixation post 2.

[0032] In the above embodiments, arc-shaped transition portions 4 are provided at the connection points between the first anti-rotation portion 31 and the second anti-rotation portion 32 and the outer peripheral side and bone side surface 12 of the fixation post 2. The arc-shaped transition portion 4 refers to a transition surface where the anti-rotation portion does not form an abrupt right-angle turn with the adjacent structure, but is connected by a continuously curved transition surface. Its curvature and width can be set according to the thickness of the anti-rotation portion, the diameter of the fixation post 2, and the thickness of the adapter body 1. When the adapter is subjected to compressive loads or tangential loads in the acromion direction, the load is transferred from the adapter body 1 to the anti-rotation portion and the fixation post 2. If the cross-section at the connection point changes drastically, the load is prone to concentrate at the root of the anti-rotation portion. The arc-shaped transition portion 4 allows the cross-section to gradually change at this point, expanding the load transfer area between the anti-rotation portion and the fixation post 2 and the bone side surface 12, thus dispersing bending stress and shear stress along the transition surface. The arc-shaped treatment at the connection points of the two anti-rotation portions also avoids abrupt stiffness changes on one side, thereby improving the consistency of stress on both anti-rotation structures and reducing the possibility of localized damage to the root of the anti-rotation portion under long-term alternating loads.

[0033] In one example, the length of the first anti-rotation part 31 extending along the axial direction of the fixing post 2 is greater than the length of the second anti-rotation part 32 extending along the axial direction of the fixing post 2, and the lengths of both the first anti-rotation part 31 and the second anti-rotation part 32 extending along the axial direction of the fixing post 2 are less than the length of the fixing post 2 extending away from the adapter body 1.

[0034] In the above embodiment, the length of the first anti-rotation part 31 extending axially along the fixation post 2 is greater than the length of the second anti-rotation part 32 extending in the same direction, and the axial extension lengths of both are less than the length of the fixation post 2 extending out of the bone side surface 12. The fixation post 2 thus has a pilot section extending beyond the end edges of the two anti-rotation parts. During installation, this pilot section can first enter the mounting hole on the humeral head to constrain the direction of the adapter's entry. After the fixation post 2 provides initial guidance, the two anti-rotation parts then enter their respective mounting areas, reducing interference between the anti-rotation parts and the bone surface before alignment.

[0035] The longer first anti-rotation portion 31 has a larger intraosseous contact area and can bear a larger circumferential restraint load on its side; the shorter second anti-rotation portion 32 provides auxiliary restraint from the opposite side and can reduce the amount of bone to be removed from the installation area on that side. The two portions create a differentiated embedding depth, which can accommodate situations where the bone surface contours or available bone volume on both sides of the humeral head implantation area are not completely consistent. The extension length of the fixation post 2 is greater than that of the two anti-rotation portions, which also allows the axial anchorage to be mainly borne by the fixation post 2, so that the anti-rotation portions focus on restricting rotation and oscillation, and prevent the end edge of the anti-rotation portion from bearing the main insertion load instead of the fixation post 2.

[0036] In one example, the fixation post 2 is a long column or a short column. The fixation post 2 includes a main body 22 and a bottom end 23 disposed at the end of the main body 22 away from the bone side surface 12. The main body 22 is cylindrical or conical, and the bottom end 23 is spherical or truncated conical. When the fixation post 2 is conical, the diameter of the fixation post 2 gradually decreases in the direction away from the bone side surface 12.

[0037] In the above embodiments, the fixation post 2 can be configured as a long post or a short post with different axial lengths to adapt to the amount of bone available for fixation in the implantation area and the predetermined installation depth. The fixation post 2 includes a main body portion 22 connected to the bone side surface 12 and a bottom end portion 23 located at the distal end of the main body portion 22, the distal end referring to the end of the fixation post 2 away from the bone side surface 12. The main body portion 22 can be a cylinder with a diameter that remains constant along the axial direction, or a cone with a diameter that gradually decreases in the direction away from the bone side surface 12; the bottom end portion 23 can form a continuously rounded spherical profile, or a truncated conical profile with tapered sides. The cylindrical main body portion 22 can maintain a relatively stable fit with the mounting hole over a large axial range, while the conical main body portion 22 can gradually form radial constraints as the insertion depth increases during the pressing process. The lateral dimension of the spherical or truncated conical bottom end portion 23 tapers distally, which can correct slight positional deviations when the fixation post 2 enters the mounting hole, reducing the situation where the edge of the post directly abuts the hole wall. The longer column can increase the intraosseous fit length of the fixation column 2, while the shorter column is suitable for installation areas with less available bone depth, so that the length of the fixation column 2 matches the local bone volume of the humeral head, avoiding insufficient fixation depth or excessive column insertion.

[0038] In one embodiment, the axis of the fixation post 2 passes through the center of curvature of the bone side surface 12.

[0039] In the above embodiment, the axis of the fixation post 2 passes through the center of curvature of the corresponding arc surface of the bony side surface 12. The bony side surface 12 is a concave arc surface, and the center of curvature is used to characterize the bending direction of the arc surface in the region where the fixation post 2 is located; the axis of the fixation post 2 passes through this center of curvature, so that the fixation post 2 extends radially along the arc surface relative to the bony side surface 12. When the adapter is installed, the insertion direction of the fixation post 2 is therefore consistent with or close to the normal direction of the corresponding position of the bony side surface 12, and the force generated by the fixation post 2 pressing into the mounting hole can be transmitted to the adapter body 1 more directly, reducing the additional bending moment caused by the fixation post 2 being inclined to the bony side surface 12. After the acromion side surface 11 is subjected to a compressive load, the load is transmitted to the bony side surface 12 and the fixation post 2 through the adapter body 1. The fixation post 2 is arranged radially along the arc surface, which is beneficial to make the axial component force borne by the mating area between the fixation post 2 and the mounting hole, and to keep the bony side surface 12 in a state of contact with the humeral head bone surface. This positional relationship also facilitates determining the drilling direction based on the curvature of the bone side surface 12, ensuring that the mounting hole corresponds to the fixation post 2, and reducing the impact of assembly misalignment on fixation stability.

[0040] In one embodiment, the surface of the anti-rotation plate 3 is provided with an array of longitudinal grooves or a rough surface, and the bone side surface 12 is provided with a bone bonding layer, which is one of a porous titanium coating, a rough layer, or a biological coating.

[0041] In the above embodiments, the surface of the anti-rotation plate 3 is provided with an array of longitudinal grooves or rough surfaces. The longitudinal grooves extend along the direction in which the anti-rotation plate 3 enters the bone tissue, and multiple longitudinal grooves are arranged at intervals to form alternating grooves and protrusions; the rough surfaces can be formed by sandblasting, etching, machining, or molding texture. After the anti-rotation plate 3 is embedded in the corresponding installation area, the longitudinal grooves or rough surfaces increase the contact interface between the anti-rotation plate 3 and the surrounding fixation medium or bone tissue, and form a microscopic limiting structure distributed along the surface of the anti-rotation plate 3. When the adapter generates a rotational tendency, the surrounding structures need to cross the grooves, protrusions, or rough undulations to move relative to each other, thus increasing the ability of the anti-rotation plate 3 to resist circumferential slippage. The bone side surface 12 is provided with a bone bonding layer, which can be a porous titanium coating with interconnected pores, a rough layer formed by surface processing, or a biological coating formed by biocompatible materials such as hydroxyapatite or calcium phosphate. The bone bonding layer expands the interfacial contact area of ​​the bone side surface 12 and provides interfacial conditions for bone tissue attachment or ingrowth, so that the long-term bonding of the bone side surface 12 and the mechanical constraints provided by the fixation post 2 and the anti-rotation plate 3 together maintain the position of the adapter.

[0042] In one embodiment, the adapter body 1, the fixing post 2, and the anti-rotation plate 3 are all integrally molded from one of the following materials: PEEK material, carbon fiber reinforced PEEK material, PEKK material, or medical polymer composite material.

[0043] In the above embodiments, the adapter body 1, the fixation post 2, and the anti-rotation plate 3 are continuously formed from the same selected material, which can be implant-grade PEEK, carbon fiber reinforced PEEK, PEKK, or a medical polymer composite material that meets implantation requirements. Here, "integrated molding" means that the three structures form an inseparable whole after manufacturing, without assembly using screws, clips, or adhesive layers, and can be obtained through injection molding, compression molding, additive manufacturing, or integral processing. When the load borne by the acromial lateral surface 11 is transferred from the adapter body 1 to the bone lateral surface 12, the fixation post 2, and the anti-rotation plate 3, the continuous material structure avoids abrupt load changes at the assembly interface and eliminates the problem of relative structural displacement caused by fastener loosening.

[0044] PEEK and PEKK can form stable arc-shaped bodies and detailed structures. Carbon fiber reinforced PEEK can improve structural stiffness and load-bearing capacity while retaining molding capability, while medical polymer composite materials can select appropriate reinforcing components according to the predetermined load. The combination of material selection and integrated structure can maintain the positional relationship between the fixing column 2 and the anti-rotation plate 3 relative to the adapter body 1, avoiding weakening of support stability due to loosening of component connections during long-term stress. Moreover, the integrated molding of the structure also significantly improves production efficiency, eliminating the process of assembling multiple parts, reducing dimensional errors generated during processing and assembly, lowering manufacturing costs, ensuring product consistency, and better adapting to the needs of large-scale clinical applications.

[0045] The present invention also provides a method for installing a humeral head acromion adapter, using the humeral head acromion adapter as described in any of the preceding claims, comprising: S1. Provide a mounting base, drill holes in the mounting base according to the shape of the fixing column 2 to form mounting holes, and cut the edge of the mounting holes according to the shape of the anti-rotation plate 3 to form mounting grooves. In step S1, the mounting base corresponds to the bony mounting area on the humeral head used to support the adapter, or it can be a bony model corresponding to the morphology of the humeral head. The diameter, depth, and drilling direction of the mounting hole are determined based on the cross-sectional shape, outer diameter, and extension length of the fixation post 2, ensuring that the mounting hole can accommodate the fixation post 2 and maintain a predetermined gap for bone cement filling. Based on the circumferential position, thickness, and extension profile of the anti-rotation plate 3 relative to the fixation post 2, a mounting groove corresponding to the anti-rotation plate 3 is cut at the edge of the mounting hole, and the mounting groove is connected to the mounting hole. The mounting hole accommodates the fixation post 2 and establishes axial positioning, while the mounting groove accommodates the anti-rotation plate 3 and establishes circumferential positioning; their positional relationship corresponds to the positional relationship between the fixation post 2 and the anti-rotation plate 3. After the fixation post 2 enters the mounting hole, the mounting hole restricts its movement along the bone surface; after the anti-rotation plate 3 enters the mounting groove, the groove wall of the mounting groove can abut against the anti-rotation plate 3 when the adapter tends to rotate, thereby forming a mounting base combining axial positioning and circumferential restraint.

[0046] S2. Based on the gap between the fixing post 2 and the mounting hole and the gap between the anti-rotation plate 3 and the mounting groove, inject bone cement in a measured amount into the mounting hole and / or mounting groove; In step S2, the amount of bone cement injected is determined based on the gaps between the fixing post 2 and the mounting hole, and between the anti-rotation plate 3 and the mounting groove. These gaps can be obtained by subtracting the volume of the corresponding embedded portions of the fixing post 2 and the anti-rotation plate 3 from the internal volume of the mounting hole and the mounting groove, and the actual injection amount is determined by considering the flow margin of the bone cement during the pressing process. Bone cement can be injected into the mounting hole, the mounting groove, or both, ensuring sufficient bone cement in the corresponding gaps after the fixing post 2 and the anti-rotation plate 3 are pressed in, preventing large-area gaps due to insufficient injection or excessive overflow due to excessive injection. When the bone cement is in a flowable and malleable state, it can be redistributed along the outer periphery of the fixing post 2 and the surface of the anti-rotation plate 3 during subsequent pressing. Quantitative injection ensures that the distribution range of the bone cement corresponds to the preset fixing area, forming a continuous connecting medium between the fixing post 2 and the hole wall, and between the anti-rotation plate 3 and the groove wall, and preventing uncontrolled bone cement usage from affecting the adhesion of the bone side surface 12.

[0047] S3. When the bone cement is in a plastic state, the fixation post 2 and the anti-rotation plate 3 are pressed into the mounting hole and the mounting groove respectively, so that the bone cement is distributed between the fixation post 2 and the hole wall of the mounting hole and / or between the anti-rotation plate 3 and the groove wall of the mounting groove. During the pressing process, the bone cement is prevented from overflowing to the bone side surface 12. In step S3, while the bone cement remains in a malleable state, the fixing post 2 is aligned with the mounting hole, and the anti-rotation plate 3 is aligned with the mounting groove. Pressure is then applied to the adapter body 1 along the insertion direction of the fixing post 2. As the fixing post 2 enters the mounting hole, it compresses the bone cement, causing it to flow along the outer periphery of the fixing post 2 towards the hole wall and fill local gaps. Simultaneously, the anti-rotation plate 3 enters the mounting groove, allowing the bone cement to enter between the surface of the anti-rotation plate 3 and the groove wall. Maintaining a stable injection speed and force direction reduces the increase in unilateral gaps caused by the tilting of the fixing post 2 and prevents the edge of the anti-rotation plate 3 from contacting the opening of the mounting groove. By controlling the injection volume, injection depth, and injection speed, the bone cement is confined to the fixing area corresponding to the mounting hole and mounting groove; if necessary, excess bone cement squeezed out can be collected and removed from the hole opening. Preventing spillage onto the bone side surface 12 does not require the complete absence of any trace spillage, but rather avoids the formation of a continuous and uncontrollable layer of bone cement between the bone side surface 12 and the mounting substrate, so as not to hinder the adhesion between the concave arc-shaped bone side surface 12 and the surface of the mounting substrate.

[0048] S4. Maintain the position of the adapter body 1 relative to the mounting base, so that the bone side surface 12 is attached to the surface of the mounting base, and the acromion side surface 11 is set away from the mounting base, until the bone cement solidifies to form a fixed structure.

[0049] In step S4, after the fixation post 2 and anti-rotation plate 3 reach the predetermined installation depth, the adapter body 1 is maintained relative to the mounting base, and a stable holding force is applied along the direction of the bone side surface 12 toward the mounting base, so that the concave arc-shaped bone side surface 12 fits against the surface of the mounting base. The acromion side surface 11 is positioned away from the mounting base, so that the convex arc surface faces the lower surface of the acromion after installation. During the holding period, axial displacement, circumferential rotation, or lateral swing of the adapter body 1 is prevented, so that the bone cement maintains a predetermined distribution state between the fixation post 2 and the wall of the mounting hole, and between the anti-rotation plate 3 and the wall of the mounting groove. After the bone cement cures, it covers the embedded parts of the fixation post 2 and the anti-rotation plate 3 respectively, and forms a fixed connection with the hole wall and the groove wall. The cured structure around the fixation post 2 bears the axial load, the cured structure on both sides of the anti-rotation plate 3 bears the circumferential load and the eccentric load, and the bone side surface 12 disperses and transmits the pressure borne by the adapter body 1 to the mounting base, thereby maintaining the implantation position of the adapter and providing a stable fixation base for the continuous support of the acromion side surface 11.

[0050] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A humeral head acromion adapter, characterized in that, The adapter body (1) is formed in an arc shape with an acromial side surface (11) and a bony side surface (12), which are arranged opposite to each other. The bony side surface (12) is provided with a fixation post (2) extending away from the adapter body (1). An anti-rotation plate (3) is provided on the outer periphery of the fixation post (2). The anti-rotation plate (3) extends in a triangular shape along the outer periphery of the fixation post (2) to the bony side surface (12). The acromion side surface (11) is an outwardly convex arc surface, and the bony side surface (12) is an inwardly concave arc surface. The adapter body (1), the fixation post (2), and the anti-rotation plate (3) are integrally formed.

2. The humeral head acromion adapter according to claim 1, characterized in that, The outer periphery of the fixation post (2) is provided with a plurality of recessed grooves (21). The recessed grooves (21) extend along the axial direction of the fixation post (2). The plurality of recessed grooves (21) are arranged in a circular array around the axis of the fixation post (2). One end of the recessed groove (21) extends to the bone side surface (12). The other end of the recessed groove (21) is distributed between the end of the fixation post (2) away from the adapter body (1) and the anti-rotation plate (3) for bone cement to be embedded and installed.

3. The humeral head acromion adapter according to claim 1, characterized in that, The anti-rotation plate (3) includes a first anti-rotation part (31) and a second anti-rotation part (32), which are symmetrically distributed on opposite sides of the fixed column (2) along the axis of the fixed column (2).

4. The humeral head acromion adapter according to claim 3, characterized in that, An arc-shaped transition portion (4) is provided at the connection between the first anti-rotation portion (31) and the bone side surface (12) and the fixation post (2), as well as at the connection between the second anti-rotation portion (32) and the bone side surface (12) and the fixation post (2).

5. The humeral head acromion adapter according to claim 3, characterized in that, The length of the first anti-rotation part (31) extending along the axial direction of the fixed post (2) is greater than the length of the second anti-rotation part (32) extending along the axial direction of the fixed post (2), and the lengths of the first anti-rotation part (31) and the second anti-rotation part (32) extending along the axial direction of the fixed post (2) are both less than the length of the fixed post (2) extending away from the adapter body (1).

6. The humeral head acromion adapter according to claim 1, characterized in that, The fixation post (2) is a long post or a short post. The fixation post (2) includes a main body (22) and a bottom end (23) disposed at the end of the main body (22) away from the bone side surface (12). The main body (22) is cylindrical or conical, and the bottom end (23) is spherical or truncated conical. When the fixation post (2) is conical, the diameter of the fixation post (2) gradually decreases along the direction away from the bone side surface (12).

7. The humeral head acromion adapter according to claim 1, characterized in that, The axis of the fixation post (2) passes through the center of curvature of the bone side surface (12).

8. The humeral head acromion adapter according to claim 1, characterized in that, The surface of the anti-rotation plate (3) is provided with one of an array of longitudinal grooves or a rough surface, and the bone side surface (12) is provided with a bone bonding layer, which is one of a porous titanium coating, a rough layer or a biological coating.

9. The humeral head acromion adapter according to claim 1, characterized in that, The adapter body (1), the fixing post (2) and the anti-rotation plate (3) are all integrally molded from one of the following materials: PEEK material, carbon fiber reinforced PEEK material, PEKK material or medical polymer composite material.

10. A method for installing a humeral head acromion adapter, characterized in that, The humeral head acromion adapter as described in any one of claims 1-9 comprises: S1. Provide a mounting base, drill holes in the mounting base according to the shape of the fixing column to form mounting holes, and cut the edges of the mounting holes according to the shape of the anti-rotation plate to form mounting grooves. S2. Based on the gap between the fixing post and the mounting hole and between the anti-rotation plate and the mounting groove, inject bone cement in a measured amount into the mounting hole and / or mounting groove; S3. When the bone cement is in a plastic state, press the fixation post and the anti-rotation plate into the mounting hole and mounting groove respectively, so that the bone cement is distributed between the wall of the fixation post and the wall of the mounting hole and / or between the anti-rotation plate and the wall of the mounting groove. During the pressing process, prevent the bone cement from overflowing to the bone side surface. S4. Maintain the position of the adapter body relative to the mounting base, so that the bone side surface is in contact with the surface of the mounting base and the acromion side surface is facing away from the mounting base, until the bone cement hardens to form a fixed structure.

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