Prosthesis for shoulder joint

Abstract

This invention discloses a prosthesis for the shoulder joint. The prosthesis includes a limiting structure and a protective structure connected to the limiting structure; the limiting structure has an arc along the coronal plane. This prosthesis conforms to the physiological structure of the human shoulder joint, self-limiting itself within the subacromial space, reducing adverse events such as foreign body sensation, dislocation, and functional failure in patients. The protective structure provides support within the space between the humeral head and the acromion of the human shoulder joint, while simultaneously shifting the humeral head upwards in patients with rotator cuff injuries, avoiding pain caused by tissue impingement and increasing the lever arm of the deltoid muscle, thus immediately improving shoulder joint function. The limiting structure at least partially conforms to the humeral head of the human shoulder joint to limit its movement and prevent prosthesis displacement.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and in particular to a prosthesis for the shoulder joint. Background Technology

[0002] The rotator cuff is a musculoskeletal structure connecting the scapula and the head of the humerus, located on the outer layer of the shoulder joint capsule and the inner layer of the deltoid muscle. The rotator cuff consists of the anterior rotator cuff (subscapularis), superior rotator cuff (supraspinatus), and posterior rotator cuff (infraspinatus and teres minor). Besides its function of internally, externally, and abducting the upper arm, the rotator cuff's primary function is to stabilize the position of the humeral head within the glenoid fossa, preventing it from shifting upwards and impinging on the acromion, thus avoiding pain. Therefore, the rotator cuff plays a crucial role in maintaining shoulder joint stability and facilitating shoulder joint movement. However, with age, long-term repetitive shoulder joint activity, subacromial osteophyte formation, or repetitive strenuous activity can cause wear and tear of the subacromial soft tissues (bursae and rotator cuff), impairing the stability and mobility of the humeral head. During shoulder joint movement, patients may be unable to abduct or raise their arm, and the impingement between bones or between the bone and the rotator cuff can cause severe pain, leading to insomnia and significantly impacting their quality of life and ability to care for themselves.

[0003] Currently, treatment for rotator cuff injuries mainly includes surgery and prosthesis implantation. For mild rotator cuff injuries, surgery can achieve good results, but for injuries larger than 3cm, the effectiveness of surgery is uncertain and recurrence is common. Prosthesis implantation artificially restricts the upward movement of the humeral head, avoiding pain caused by tissue impingement, and also increases the lever arm of the deltoid muscle, thus immediately improving shoulder joint function. However, existing prostheses, such as prosthetic devices and bio-pads, may shift during patient activity. For example, displacement of the prosthetic device may alter pressure distribution, leading to prosthesis rupture, and the release of deteriorated contents at a prolonged 37° angle, causing further damage to the affected area. Furthermore, the injection port is made of a rigid material, which may cause discomfort and a foreign body sensation during certain movements after implantation. Displacement of the bio-pad may cause discomfort, limited mobility, or even damage to surrounding soft tissues, further exacerbating the injury. In addition, existing prosthetic implants have the potential for failure. Summary of the Invention

[0004] Therefore, it is necessary to provide a shoulder joint prosthesis that conforms to the physiological structure of the human shoulder joint, self-limits to the subacromial space to solve the problem of implant displacement, and reduces the occurrence of adverse events.

[0005] A prosthesis for a shoulder joint includes a limiting structure and a protective structure connected to the limiting structure; the limiting structure has an arc along the coronal plane.

[0006] In one embodiment, the limiting structure has a first surface and a second surface, both of which are curved surfaces, the second surface being used to fully or partially fit the large nodule, and the protective structure being used to support the acromion.

[0007] In one embodiment, the limiting structure has an arc along the sagittal plane.

[0008] In one embodiment, the radius of curvature of the second surface of the limiting structure is 10 to 50 mm.

[0009] In one embodiment, the thickness of the limiting structure gradually increases from the end furthest from the protective structure to the end connected to the protective structure.

[0010] In one embodiment, the edges of the limiting structure are arc-shaped.

[0011] In one embodiment, the maximum width of the limiting structure is greater than the maximum width of the protective structure.

[0012] In one embodiment, the thickness H1 of the protective structure is 4-14 mm.

[0013] In one embodiment, the straight length H2 of the limiting structure along the sagittal plane is H1+15mm.

[0014] In one embodiment, the protective structure includes an arc segment, the two endpoints of which form an isosceles trapezoid with the line connecting the maximum width of the limiting structure.

[0015] In one embodiment, the curvature of the arc segment is ≤0.21mm. -1 .

[0016] In one embodiment, the lower base angle of the isosceles trapezoid ranges from 45° to 90°.

[0017] In one embodiment, the limiting structure has a first accommodating cavity, and the protective structure has a second accommodating cavity communicating with the first accommodating cavity, both the first accommodating cavity and the second accommodating cavity being used for filling with filler.

[0018] In one embodiment, the limiting structure and / or the protective structure is provided with an injection hole, the injection hole being connected to the first accommodating cavity and the second accommodating cavity, and a one-way valve being provided in the injection hole.

[0019] This invention relates to a shoulder joint prosthesis that conforms to the physiological structure of the human shoulder joint, self-confining within the subacromial space, thus reducing adverse events such as foreign body sensation, dislocation, and functional failure in patients. The protective structure provides support within the space between the humeral head and the acromion of the shoulder joint, while simultaneously shifting the humeral head upwards in patients with rotator cuff injuries, avoiding pain caused by tissue impingement. This also increases the lever arm of the deltoid muscle, immediately improving shoulder joint function. The confining structure at least partially conforms to the humeral head of the shoulder joint to limit prosthesis displacement.

[0020] The first and second surfaces of the restraining structure of the prosthesis for the shoulder joint of the present invention are both curved surfaces, so that the restraining structure fits completely or partially with the human humeral head or greater tubercle, thereby allowing the restraining structure to play a maximum limiting role and avoiding prosthesis displacement to the greatest extent.

[0021] The limiting structure of the prosthesis used in this invention for the shoulder joint has an arc-shaped edge. This arc-shaped structure can adapt to the physiological shape of the shoulder joint and the top of the rotator cuff, without restricting the patient's movement or damaging the surrounding soft tissue.

[0022] The prosthesis of this invention for the shoulder joint has a first receiving cavity in its restricting structure and a second receiving cavity communicating with the first receiving cavity in its protective structure. After filling material is injected into the restricting and protective structures, the protective structure can conform to the rotator cuff, preventing the rotator cuff from impinging on the acromion or other tissue structures during shoulder joint movement, and maintaining the distance between the humeral head and the acromion, thus maintaining the lever arm length of the shoulder joint and reducing muscle load. The restricting structure can tightly engage with the humeral head of the human shoulder joint, improving its limiting ability. Filling liquids or colloids can be injected into the restricting and protective structures to achieve conformity with the physiological structure of the joint, effectively improving shoulder joint function in patients with rotator cuff injuries. Furthermore, the prosthesis's special shape adapts to the special physiological structure of the human shoulder joint, achieving better support, reducing impingement, and obtaining better therapeutic effects.

[0023] In order to reduce the possible foreign body sensation caused to patients after implantation, the prosthesis of the shoulder joint of the present invention has the following design: when both the first accommodating cavity and the second accommodating cavity are filled with filler, the thickness of the restricting structure gradually increases from the end away from the protective structure to the end connected to the protective structure. That is, the restricting structure is designed to be thinner on the outer side and gradually thicker towards the head, so as to reduce the impact of the restricting structure on the humeral head during movement. Attached Figure Description

[0024] Figure 1 A schematic diagram of the various anatomical planes of the human body;

[0025] Figure 2 This is a side sectional view of a shoulder joint prosthesis according to an embodiment of the present invention;

[0026] Figure 3 for Figure 1 The diagram shown is a top view of a prosthesis for the shoulder joint.

[0027] Figure 4 for Figure 1 The diagram shown is a rear view of a prosthesis used for the shoulder joint.

[0028] Figure 5 for Figure 1 The diagram shown is a frontal view of a prosthesis used for the shoulder joint.

[0029] Figure 6 for Figure 1 The diagram shows a side view of a prosthesis used for the shoulder joint.

[0030] Figure 7 for Figure 1 The diagram shown illustrates the integration of a shoulder joint prosthesis with the human body.

[0031] Figure 8 This is a side view of a prosthesis for a shoulder joint according to another embodiment; wherein, L1 is the length of the prosthesis for the shoulder joint along the coronal plane, L2 is the length of the protective structure in the prosthesis for the shoulder joint along the coronal plane, H1 is the height of the protective structure in the prosthesis for the shoulder joint along the sagittal plane, and H2 is the height of the prosthesis for the shoulder joint along the sagittal plane.

[0032] Figure 9 This is a top view schematic diagram of a prosthesis for a shoulder joint according to another embodiment; wherein, L3 is the width of the protective structure in the prosthesis for a shoulder joint along the horizontal plane, and L4 is the width of the restrictive structure in the prosthesis for a shoulder joint along the horizontal plane.

[0033] Figure 10 This is a top view schematic diagram of a prosthesis for the shoulder joint according to another embodiment;

[0034] Figure 11 This is a top view schematic diagram of a prosthesis for the shoulder joint according to another embodiment.

[0035] Explanation of reference numerals in the attached figures

[0036] 10: Prosthesis for shoulder joint; 100: Restriction structure; 110: First accommodating cavity; 200: Protective structure; 210: Second accommodating cavity; 300: Injection port; 400: Injection tube; 500: One-way valve; 600: Filler. Detailed Implementation

[0037] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0039] See Figure 1 As shown, Figure 1 This is a schematic diagram defining the various anatomical planes of the human body. Among them, the sagittal plane 101 is a longitudinal section that divides the human body or joint into left and right parts from the front-to-back direction. The sagittal plane passing through the center of the human body is called the median sagittal plane, which divides the human body into two equal parts. The coronal plane 102 is a longitudinal section that divides the human body or joint into front-to-back parts from the left-to-right direction. This section is perpendicular to the sagittal plane. The horizontal plane 103, also called the transverse plane, is a plane parallel to the ground plane that divides the human body or joint into upper and lower parts. This plane is perpendicular to both the coronal and sagittal planes.

[0040] See Figure 2 As shown, an embodiment of the present invention provides a prosthesis 10 for a shoulder joint, comprising a limiting structure 100 and a protective structure 200 connected to the limiting structure 100. The limiting structure 100 has an arc along the coronal plane, or the limiting structure 100 and the protective structure 200 have an angle along the coronal plane. Preferably, the limiting structure 100 has an arc along both the coronal and sagittal planes, and the radius of curvature of the inner surface of the limiting structure 100 is 10 to 50 mm. Specifically, the limiting structure 100 has a first surface and a second surface, both of which are curved surfaces; for example, the second surface is an inner surface (e.g., ...). Figure 2 (The surface shown facing downwards). See also Figure 7As shown, the second surface is used to fully or partially conform to the humeral head and / or greater tuberosity, extending from the humeral head and at least partially covering the greater tuberosity. The inventors have discovered that, compared to only covering the humeral head, the second surface of the limiting structure 100 partially or fully covering the greater tuberosity can prevent prosthesis displacement during activities such as abduction and internal rotation of the arm, while simultaneously protecting rotator cuff tendon tears within the prosthesis limiting structure, further preventing severe pain caused by impact between the tear and bone. Therefore, the limiting structure 100 can exert its optimal limiting effect, minimizing prosthesis displacement for the shoulder joint. Preferably, the limiting structure 100 can be a semi-bowl-shaped structure, which conforms to the humeral head and functions to maintain the position of the entire prosthesis for the shoulder joint. It is understood that in other embodiments, the structure and shape of the limiting structure 100 are not limited to those described above; the structure and shape of the limiting structure 100 can also be a semi-basin-shaped, semi-bowl-shaped, etc.

[0041] See Figure 7 As shown, the protective structure 20 is used to support the acromion within the gap between the humeral head and the acromion of the human shoulder joint.

[0042] Further, see Figure 4 and Figure 5 As shown, the edge of the restriction structure 100 is arc-shaped and smooth. This arc-shaped structure can adapt to the physiological shape of the shoulder joint and the top of the rotator cuff, reducing the damage to muscle tissue caused by the outer edge of the restriction structure 100 during shoulder joint movement.

[0043] Further, see Figure 2 and Figure 3 As shown, the maximum width of the limiting structure 100 is greater than the maximum width of the protective structure 200. Preferably, see [reference needed]. Figure 8As shown, the width L4 at the transition point between the restricting structure 100 and the protective structure 200 is greater than the width L3 of the protective structure 200. This design improves the fit between the restricting structure 100 and the humeral head and greater tuberosity of the human shoulder joint, and helps to prevent displacement of the protective structure 200 and the entire prosthesis used for the shoulder joint at the subacromial bursa fold. Preferably, the restricting structure 100 and / or the protective structure 200 are deformable. This deformation can be a recovery deformation after compression, an expansion deformation after filling with filler, or other forms of deformation. The deformability of the restricting structure 100 and / or the protective structure 200 allows for a fit with the humeral head of the human shoulder joint and the gap between the humeral head and the acromion, adapting to the special physiological structure of the human shoulder joint, achieving better support, reducing impingement, and obtaining better therapeutic effects. During the filling process, the limiting structure 100 and / or the protective structure 200 adapt to the physiological structure of the shoulder joint through deformation, such as self-expansion after compression or expansion after filling. They can fit the human humeral head and, together with the physiological structure of the shoulder joint bursa fold, limit the medial and lateral displacement of the prosthesis used in the shoulder joint, self-limiting it to the subacromial space to avoid dislocation. In addition, the adaptive function brought about by deformation ensures that the limiting structure 100 and the protective structure 200 will not restrict the patient's movement or damage the surrounding soft tissues.

[0044] In another embodiment, see Figure 8 As shown, H1 is the height of the protective structure 200 in the sagittal plane of the prosthesis 10 for the shoulder joint, which is also the thickness of the protective structure 200, preferably 4-14 mm. According to the elastic mechanical principle of a sealed cavity under pressure, P = σ·h / r, where P is the maximum pressure that the cavity can withstand, σ is the circumferential stress intensity of the cavity shell material, h is the wall thickness of the cavity shell, and r is the minimum radius of the cavity. At the subacromial space of the shoulder joint prosthesis implanted in this invention, the maximum pressure exerted between the acromion and the humeral head is approximately 88 kPa (i.e., P = 88 kPa). The height H1 of the protective structure of the shoulder joint prosthesis is 4-14 mm (i.e., the minimum radius r of the protective structure cavity is 2-7 mm). Therefore, the value of σ·h ranges from 176 to 616 kPa·mm. This value guides the selection of the shoulder joint prosthesis material and the specific design of the wall thickness. For example, when the wall thickness h of the shoulder joint prosthesis is 0.1 mm, materials with a strength σ in the range of 1760-6160 kPa can be selected. In practice, commonly used non-degradable and degradable medical materials such as polyamide, polyester, polyethylene, polylactic acid, and polycaprolactone can meet this requirement. Therefore, H1 is preferably 4-14 mm, which allows the shoulder joint prosthesis to achieve the function of supporting the humeral head and acromion under the conditions of commonly used medical materials and conventional manufacturing precision.

[0045] H2 is the height of the prosthesis 10 for the shoulder joint along the sagittal plane, which is preferably 9-34 mm. More preferably, the straight length H2 of the restricting structure 100 along the sagittal plane is H1+15 mm. This setting can achieve the restriction structure 100 covering the greater tubercle of the humeral head while avoiding the restriction structure 100 being too large and hindering the movement of the rotator cuff muscles.

[0046] See Figure 8 As shown, L1 is the length of the prosthesis 10 for the shoulder joint along the coronal plane, which is preferably 30-70 mm. L2 is the length of the protective structure 200 in the prosthesis 10 for the shoulder joint along the coronal plane, which is preferably 10-40 mm. See also Figure 9 As shown, L3 is the width of the protective structure 200 in the shoulder joint prosthesis 10 along the horizontal plane, which is preferably 15-60 mm. L4 is the width of the restraining structure 100 in the shoulder joint prosthesis 10 along the horizontal plane, which is preferably 20-70 mm. The above arrangement enables the protective structure 200 to separate the acromion from the humeral head, and the restraining structure 100 to cover the humeral head and greater tuberosity, thereby preventing dislocation.

[0047] The aforementioned prostheses 10 for the shoulder joint of different sizes are suitable for humeral heads of different diameters. For example, when suitable for a humeral head diameter of 5 cm, it is preferable that H1 is 10-12 mm, H2 is 25-27 mm, L1 is 55-65 mm, L2 is 25-35 mm, L3 is 30-50 mm, L4 is 55-60 mm, and the radius of curvature of the inner surface of the constriction structure 100 is 25-30 mm.

[0048] See Figure 8 As shown, the thickness of the limiting structure 100 gradually increases from the end away from the protective structure 200 to the end connected to the protective structure 200.

[0049] Figure 10 This is a top view of another embodiment of the shoulder joint prosthesis. (See attached image.) Figure 10 As shown, the lines connecting the maximum widths of the limiting structure 100 form points D and C. The protective structure 200 includes arc segments, the endpoints of which form points A and B. Points A, B, C, and D form an isosceles trapezoid. This structure can improve the transmission of horizontal force between the AB and CD sides of the protective structure. During arm abduction and elevation, the humeral head rotates inward toward the shoulder socket, creating a horizontal force on the protective structure from CD to AB, causing horizontal compression between the protective structures. The large-angle trapezoidal profile design reduces the loss of force transmission between the two edges, thus reducing internal strain and deformation / wrinkling of the protective structure during arm abduction. More preferably, the curvature of arc segment AB is ≤0.21mm. -1 The preferred curvature of the CD segment arc is ≤0.15mm. -1 .

[0050] Points A and D can be connected by one or more straight line segments, one or more curved line segments, or a straight line segment and a curved line segment. For example... Figure 11 As shown, the area between points A and B includes arc segments AB and BC, wherein the curvature of the arc segments AB and EF is preferably ≤0.3mm. -1 The curvature of the arcs in segments BC and DE is preferably ≤0.15mm. -1 .

[0051] The first receiving cavity 110 of the restricting structure 100 and the second receiving cavity 210 communicating with the first receiving cavity 110 are both used for filling with the filler 600. During the filling process, after the filler 600 is filled, the protective structure 200 can conform to the rotator cuff, preventing the rotator cuff from impacting the acromion or other tissue structures during shoulder joint movement, and can maintain the distance between the humeral head and the acromion, maintain the lever arm length of the shoulder joint movement, and reduce muscle load; the restricting structure 100 can tightly engage with the humeral head of the human shoulder joint, improving the limiting ability.

[0052] Preferably, the limiting structure 100 and the protective structure 200 can be a balloon, a sponge-like element, or a non-inflatable structure.

[0053] When the restricting structure 100 has a first accommodating cavity 110 and the protective structure 200 has a second accommodating cavity 210, the maximum thickness of the restricting structure 100 gradually increases from the end away from the protective structure 200 to the end connected to the protective structure 200. The minimum thickness of the restricting structure 100 is the thickness before filling with filler or the thickness after compressing the restricting structure 100; the maximum thickness of the restricting structure 100 is the thickness after filling with filler or the thickness in the self-recovering state after compressing the restricting structure 100. The minimum thickness of the protective structure 200 is the thickness before filling with filler or the thickness after compressing the protective structure 200; the maximum thickness of the protective structure 200 is the thickness after filling with filler or the thickness in the self-recovering state after compressing the protective structure 200.

[0054] See Figure 2As shown, when both the first accommodating cavity 110 and the second accommodating cavity 210 are filled with filler material 600, the thickness of the restricting structure 100 gradually increases from the end furthest from the protective structure 200 to the end connected to the protective structure 200. To reduce the potential foreign body sensation in patients after implantation of the prosthesis 10 for the shoulder joint, the thickness of the restricting structure 100 gradually increases from the end furthest from the protective structure 200 to the end connected to the protective structure 200 when both the first accommodating cavity 110 and the second accommodating cavity 210 are filled with filler material 600. That is, the restricting structure 100 is designed to be thinner on the outer side and gradually thicker towards the head, thus reducing the impact of the restricting structure 100 on the humeral head during movement.

[0055] In addition, the protective structure 200 can be specially optimized for different usage needs. For example, for those who need more exercise, the thickness can be appropriately increased to extend the service life.

[0056] Furthermore, when both the first accommodating cavity 110 and the second accommodating cavity 210 are filled with filler 600, the thickness of the end where the limiting structure 100 connects to the protective structure 200 is consistent with the thickness of the protective structure 200, so as to reduce discomfort in the humeral head during shoulder joint movement.

[0057] One surface of the protective structure 200 is curved to allow it to conform substantially to the rotator cuff. Specifically, the protective structure 200 is a downward-curving arc in the transverse plane. This arc conforms to the physiological shape of the shoulder joint and the tip of the rotator cuff. After the filler 600 is injected, the protective structure 200 can conform to the rotator cuff and prevent the rotator cuff from impinging on the acromion or other tissue structures during shoulder joint movement. It can also maintain the distance between the humeral head and the acromion, maintain the lever arm length of the shoulder joint, and reduce muscle load.

[0058] Further, see Figure 3 and Figure 5 As shown, the limiting structure 100 and / or the protective structure 200 are provided with an injection hole 300, which is connected to the first accommodating cavity 110 and the second accommodating cavity 210. A one-way valve 500 is provided in the injection hole 300, which can prevent the filler 600 injected through the injection hole 300 from flowing out in the reverse direction.

[0059] Further, see Figure 2 and Figure 6 As shown, the above-mentioned prosthesis 10 for the shoulder joint also includes an injection tube 400 disposed in the first accommodating cavity 110 and / or the second accommodating cavity 210 and connected to the injection hole 300. The outward-facing opening of the injection tube 400 is flush with the outer surface of the limiting structure 100 or the protective structure 200. A one-way valve 500 is disposed in the injection tube 400.

[0060] Further, see Figure 6As shown, the diameter of one end of the injection tube 400 that connects to the injection hole 300 is smaller than that of the end facing inward.

[0061] Preferably, the injection tube 400 is flexible, which effectively solves the problem of discomfort and foreign body sensation that may be caused to patients during specific actions after implantation in traditional technologies.

[0062] Further, see Figure 6 As shown, the limiting structure 100 and the protective structure 200 are connected as an integral structure. The design of the limiting structure 100 and the protective structure 200 as an integral structure facilitates mold opening and processing, and reduces manufacturing costs.

[0063] Furthermore, the limiting structure 100, the protective structure 200, and the injection tube 400 are all made of non-degradable materials. The limiting structure 100 and the protective structure 200 of the shoulder joint prosthesis 10 of this invention are both made of non-degradable materials, solving the problem of short-term degradation and failure of implants in traditional technologies. This avoids the rupture of the shoulder joint prosthesis 10, allowing it to function effectively for a long time at 37°C, and effectively preventing further damage to the affected area caused by the release of deteriorated filler.

[0064] Furthermore, the materials used to prepare the limiting structure 100 include, but are not limited to, one or more of silicone, polyurethane, rubber, polyamide, polyester, and polyolefin. The materials used to prepare the protective structure 200 include, but are not limited to, one or more of silicone, polyurethane, rubber, polyamide, polyester, and polyolefin. The materials used to prepare the injection tube 400 include, but are not limited to, one or more of silicone, polyurethane, rubber, polyamide, polyester, and polyolefin.

[0065] Further, see Figure 2 As shown, the aforementioned prosthesis 10 for the shoulder joint further includes a filler 600, which fills the first receiving cavity 110 and the second receiving cavity 210. Preferably, the filler 600 includes a liquid and / or a colloid. For example, the filler 600 is water, silicone, gel, etc.

[0066] In a preferred embodiment, the method of using the prosthesis 10 for the shoulder joint of the present invention includes the following steps:

[0067] First, an incision is made on the skin of the patient's shoulder joint, and a routine arthroscopic exploration is performed to assess the condition of the rotator cuff. If a severe rotator cuff injury is diagnosed and conventional repair methods are not suitable for treatment, the prosthesis 10 for the shoulder joint of this invention is used for interventional treatment.

[0068] Routine shoulder joint cleaning was performed to ensure adequate subacromial space and open field of vision. The size of the subacromial space and the width from the greater tubercle of the humeral head to the edge of the superior joint capsule were measured using a measuring instrument. Based on the measurement results, an appropriate size of the shoulder joint prosthesis 10 and a filler injection volume of 600 were selected.

[0069] Using an arthroscopic channel, the shoulder joint prosthesis 10, which has not yet been filled with filler 600, is placed into the subacromial space. Then, using arthroscopic instruments, the restraining structure 100 and the protective structure 200 are flattened and moved to the appropriate position under arthroscopic guidance.

[0070] Connect the syringe to the injection tube 400, and slowly inject the filler 600 into the first receiving cavity 110 and the second receiving cavity 210 of the restricting structure 100 and the protective structure 200. Disconnect the syringe from the injection tube 400, passively move the patient's affected limb, and observe whether the restricting structure 100 and the protective structure 200 are in place or displaced within the range of passive movement. If no displacement occurs, close the skin incision.

[0071] The prosthesis 10 for the shoulder joint of this invention is permanently functional, conforms to the physiological structure of the human shoulder joint, and is self-limiting within the subacromial space, reducing adverse events such as foreign body sensation, dislocation, and functional failure in patients. Fillers 600, such as liquids or colloids, can be injected into the limiting structure 100 and the protective structure 200 to achieve a close fit to the joint's physiological structure, effectively improving shoulder joint function in patients with rotator cuff injuries. Furthermore, the special shape of the prosthesis for the shoulder joint adapts to the unique physiological structure of the human shoulder joint, achieving better support, reducing impingement, and obtaining better therapeutic effects. Specifically, the protective structure 200 limits the upward displacement of the humeral head in patients with rotator cuff injuries, avoiding pain caused by interstitial impingement, and also increases the lever arm of the deltoid muscle, thus immediately improving shoulder joint function. The limiting structure 100 enables the support to achieve positional stability in the shoulder joint through its self-limiting structure, reducing adverse events such as foreign body sensation, dislocation, and functional failure in patients.

[0072] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0073] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A prosthesis for a shoulder joint, characterized in that The structure comprises a limiting structure and a protective structure connected to the limiting structure; the limiting structure has an arc along a coronal plane, the limiting structure has a first accommodating cavity, the protective structure has a second accommodating cavity communicated with the first accommodating cavity, the first accommodating cavity and the second accommodating cavity are used for filling a filler, the filler comprises a liquid and / or a gel, the thickness H1 of the protective structure is 4-14 mm, the linear length H2 of the limiting structure along a sagittal plane is H1+15 mm, and the limiting structure has an arc along a sagittal plane.

2. The prosthesis for shoulder joint as claimed in claim 1, wherein, The limiting structure has a first surface and a second surface, the first surface and the second surface of the limiting structure are both curved surfaces, the second surface is used for wholly or partially adhering to a greater tubercle, and the protective structure is used for supporting a shoulder peak.

3. The prosthesis for shoulder joint as claimed in claim 1, wherein, The radius of curvature of the second surface of the limiting structure is 10-50 mm.

4. The prosthesis for shoulder joint as claimed in claim 1, wherein, The thickness of the limiting structure gradually increases from an end far away from the protective structure to an end connected to the protective structure.

5. The prosthesis for shoulder joints according to claim 1, characterized in that, The edge of the limiting structure is arc-shaped.

6. The prosthesis for shoulder joints according to claim 1, characterized in that, The maximum width of the limiting structure is greater than the maximum width of the protective structure.

7. The prosthesis for shoulder joints according to claim 1, characterized in that, The protective structure comprises an arc segment, and two end points of the arc segment and a line connecting the maximum widths of the limiting structure form an isosceles trapezoid.

8. The prosthesis for shoulder joints according to claim 7, characterized in that, the curvature of the arc segment is ≤ 0.21 mm -1 .

9. The prosthesis for shoulder joints according to claim 8, characterized in that, The angle of a lower base angle of the isosceles trapezoid ranges from greater than or equal to 45° to less than 90°.

Images