Subacromion implantation prosthesis

Abstract

The utility model discloses a prosthesis implanted under acromion, which is positioned between the acromion and the humeral head and comprises an acromion section and a scapular glenoid section which are distributed from inside to outside, the scapular glenoid section is provided with a lower surface matched with the surface of a scapular glenoid on the acromion, and the scapular glenoid section is provided with a mounting through hole. The scapular glenoid section is fixed to the scapular glenoid by arranging a fastener in the mounting through hole, the acromion section is provided with an upper surface matched with the lower surface of the acromion, and the acromion section is further provided with a lower surface matched with the surface of the humerus head. The device can be safely and stably fixed on the shoulder glenoid cavity for a long time.

Description

Technical Field

[0001] The utility model relates to the technical field of medical equipment, in particular to a subacromial implant prosthesis. Background Art

[0002] Rotator cuff injury is a common clinical disease. Among them, large and irreparable rotator cuff tears are a common cause of shoulder pain and disability. There are many treatment options for this disease, such as conservative treatment, palliative treatment (shoulder joint cleaning), tendon transfer, subacromial balloon implantation, superior joint capsule reconstruction and reverse shoulder replacement.

[0003] Among them, conservative treatment and palliative treatment cannot solve the patient's problems.

[0004] Tendon transfers utilize healthy muscles from elsewhere in the body that are transferred to reproduce the function of the rotator cuff. These muscles can be trained postoperatively to improve the function of the transfer, but the procedure requires extensive dissection and postoperative immobilization to allow the tendon to heal, which may result in adhesive scarring, restricted muscle and tendon gliding, decreased transfer muscle strength, and possible tendon and muscle balance issues.

[0005] Superior capsule reconstruction is another treatment method that uses soft tissue to stabilize the joint. However, unlike tendon transfer, it uses passive soft tissue to achieve this. The graft used constrains the humeral head by preventing it from translating upward. However, the graft of superior capsule reconstruction is prone to tearing, resulting in poor clinical results.

[0006] Subacromial balloon implantation creates a passive barrier that limits the upward migration of the humeral head. It differs from superior capsule reconstruction in that a foreign body that can be freely placed under the acromion is used. The implant is usually absorbed after one year, but the patient will then experience shoulder symptoms similar to those before.

[0007] Reverse shoulder arthroplasty is significantly different from the above treatment methods. This procedure involves the removal of the glenoid and humeral head and their replacement with a metallic implant. This approach has been well validated in the literature for several different shoulder pathologies and is considered by many to be the definitive approach for the large number of irreparable RCTs in elderly patients with glenohumeral arthritis. However, this technique is not suitable for young, active patients with large, irreparable rotator cuff tears due to issues such as the longevity of the prosthesis. Higher complication rates have also been reported with this procedure in younger patients.

[0008] In summary, there is currently no single method for treating young, active patients with large, irreparable rotator cuff tears. Utility Model Content

[0009] The utility model aims to provide a subacromial implant prosthesis designed to solve the deficiencies of the above-mentioned technologies, so as to restore the stability and range of motion of the normal shoulder joint without replacing the glenohumeral joint.

[0010] The utility model designs a subacromial implant prosthesis, which is located between the acromion and the humeral head, and comprises an acromion section and a glenoid section distributed along the inner-outer direction, wherein the inner-outer direction refers to the relative direction after the prosthesis is placed in the human body, the glenoid section has a lower surface adapted to the glenoid surface on the acromion, the glenoid section is provided with a mounting through hole extending substantially along the upper-lower direction, the glenoid section is fixed to the glenoid by arranging a fastener in the mounting through hole, the acromion section has an upper surface adapted to the lower surface of the acromion, and the acromion section also has a lower surface adapted to the surface of the humeral head.

[0011] Further optimized, the lower surface of the glenoid segment presents a trabecular porous grid structure.

[0012] Preferably, the upper surface of the acromion segment is a trabecular porous grid structure.

[0013] Preferably, the lower surface of the acromion segment is an arc-shaped surface, and its curvature radius is greater than the curvature radius of the humeral head.

[0014] Preferably, the lower surface of the acromion segment is smooth.

[0015] Preferably, the lower surface of the shoulder segment is highly polished.

[0016] Preferably, the edge or side of the shoulder segment is chamfered.

[0017] Further optimization also includes a connecting segment connecting the acromion segment and the glenoid segment.

[0018] Preferably, the inner and outer sides of the connecting section respectively have a front arc surface and a rear arc surface, and the curvature radius of the front arc surface is smaller than the curvature radius of the rear arc surface.

[0019] Preferably, the prosthesis is made entirely or on its surface from a rigid material.

[0020] The technical effects of the utility model are:

[0021] 1. The prosthesis is placed between the acromion and the humeral head. The glenoid segment of the prosthesis is adapted to contact with the glenoid, and the acromion segment of the prosthesis is adapted to contact with the acromion to maintain the distance between the acromion and the humeral head, thereby directly isolating the collision between the humeral head and the acromion bone structure, thereby alleviating the corresponding pain, and at the same time restoring the rotation center of the humeral head, thereby improving the mobility of the shoulder joint. Therefore, it is suitable for treating young, active and huge irreparable rotator cuff tears. The bone structure of the patient's shoulder joint can be preserved. In addition, whether the patient suffers from glenohumeral arthritis does not affect the application of the prosthesis. The reverse shoulder replacement surgery can be performed when the patient is older and the prosthesis is loose in the later stage. Therefore, the prosthesis can not only increase the age of joint replacement surgery, but also preserve sufficient bone conditions for later joint replacement and improve the treatment effect.

[0022] 2. The glenoid segment of the prosthesis is provided with mounting holes penetrating the upper and lower surfaces, and is fixedly connected to the glenoid by fasteners, thereby achieving stable and long-term fixation of the prosthesis.

[0023] 3. The surfaces of the acromion segment and the glenoid segment that contact the acromion and the humeral head respectively are both arc-shaped surfaces, making the contact more close.

[0024] 4. The surfaces of the prosthesis in contact with the acromion and humeral head are all set to a porous grid structure like trabeculae, which is convenient for new bone structure to grow into the hole structure and facilitates long-term stable fixation between the prosthesis and the acromion and glenoid. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the anatomical structure of the human shoulder;

[0026] Figure 2 is a structural diagram of a prosthesis of an embodiment installed between the acromion and the humeral head, and the clavicle is not shown because it is not directly related to the prosthesis;

[0027] Figure 3 yes Figure 2 A top view of the prosthesis structure;

[0028] Figure 4 yes Figure 2 Side view of the prosthesis structure;

[0029] Figure 5 yes Figure 2 Bottom view of the prosthesis structure.

[0030] In the figure: 1, acromion; 101, clavicle; 2, humerus; 21, humeral head; 3, acromion segment; 31, second porous network structure; 4, connecting segment; 41, anterior arc surface; 42, posterior arc surface; 5, glenoid segment; 51, mounting through hole; 52, first porous grid structure; 6, fastener; 70, scapula; 71, glenoid; 711, glenoid labrum; 72, supraglenoid tubercle; 73, coracoid process. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the utility model. Figure 1 As shown, the bony structure at the human shoulder includes an acromion 1, a scapula 70 and a humerus 2. A glenoid 71 is formed on the scapula 70. A humeral head 21 is formed on the humerus 2 to fit in the glenoid 71. A glenoid labrum 711 is attached to the periphery of the glenoid 71. An acromion 1 and a coracoid process 73 are provided on the scapula 70. The glenoid 71 is formed at the supraglenoid tubercle 72. The outer end of the clavicle 101 extends to the vicinity of the acromion 1.

[0032] In this embodiment, Figure 2-5 As shown, a prosthesis for human body includes an acromion segment 3 and a glenoid segment 5 distributed along the inner and outer directions after implantation into human body, and a connecting segment 4 is also provided between the acromion segment 3 and the glenoid segment 5. The acromion segment 3, the connecting segment 4 and the glenoid segment 5 are sequentially connected and smoothly transitioned to form an integrated prosthesis structure. The prosthesis is in a "semi-disc-shaped" structure as a whole. The prosthesis is placed in the shoulder joint cavity of the human shoulder joint, that is, placed between the acromion 1 and the humeral head 2 to maintain the spacing between the acromion 1 and the humeral head 2, and improve the mobility of the shoulder joint. The glenoid segment 5 is a "disc-shaped" structure that is narrow in front and wide in the back, and has a certain thickness. It has an upper surface and a lower surface. The upper surface is a plane or arc surface, and the lower surface is an arc surface that is narrow in front and wide in the back. A side portion is formed between the upper and lower surfaces, and the lower surface of the glenoid segment 5 contacts the supraglenoid tubercle 72.

[0033] Therefore, the lower surface of the glenoid segment 5 is adapted to the surface shape of the supraglenoid tubercle 72 of the scapula 70, so as to fit the supraglenoid tubercle 72. The glenoid segment 5 is provided with a mounting through hole 51 that penetrates the upper and lower surfaces and extends substantially in the up-down direction. A fastener 6 such as a screw or bolt is arranged in the mounting through hole 51. The fastener 6 passes through the mounting through hole 51 from top to bottom and is fixedly connected with the supraglenoid tubercle 72, so that the glenoid segment 5 is fixedly connected with the scapula 70 through the fastener 6, thereby making the entire prosthesis fixedly connected with the scapula 70. Among them, the mounting through hole 51 can have an appropriate inclination angle relative to the up-down direction or be arranged in a strictly vertical up-down direction, as long as the fastening purpose can be achieved.

[0034] The lower surface of the glenoid segment 5 presents a first porous grid structure 52 in the shape of bone trabeculae, that is, a microporous structure, which facilitates bone growth into the grid micropores to increase the fixation stability between the glenoid segment 5 and the scapula 70 .

[0035] The acromion segment 3 is an "elliptical disc" structure that is wide in front and narrow in the back and has a certain thickness. It also has an upper surface and a lower surface, and its upper surface is a plane or an arc surface. In this embodiment, the upper surface of the acromion segment 3 is a convex arc surface, which is adapted to the lower surface of the acromion 1 that is a concave arc surface, so that the upper surface of the acromion segment 3 and the acromion 1 can fit in place, and the lower surface of the acromion segment 3 contacts the humeral head 2 and adapts to the surface of the humeral head 2; in other embodiments, the upper surface of the acromion segment 3 can also be a flat surface. If the lower surface of the acromion is a non-flat surface during the implantation, the lower surface of the acromion can be polished during the operation.

[0036] In this embodiment, the lower surface of the acromion segment 3 is an inwardly concave arc surface, which fully fits with the surface of the humeral head 2 which is an outwardly convex arc surface structure.

[0037] Preferably, the upper surface of the acromion segment 3 presents a second porous grid structure 31 in the shape of bone trabeculae, that is, a microporous structure, which facilitates bone growth into the grid micropores to increase the fixation stability between the acromion segment 3 and the lower surface of the acromion 1 .

[0038] Preferably, the lower surface of the acromion segment 3 is a concave arc surface, and its curvature radius is greater than the curvature radius of the humeral head 2, that is, the arc radius of the arc surface of the lower surface is greater than the arc radius of the surface of the humeral head 2, which facilitates the movement of the humeral head 2 along the acromion segment 3.

[0039] Preferably, the lower surface of the acromion segment 3 is smooth to avoid friction between the humeral head 2 and the acromion segment 3 to cause wear.

[0040] Preferably, the lower surface of the shoulder segment 3 is subjected to high polishing treatment, so that the lower surface of the shoulder segment 3 is smooth.

[0041] Preferably, the edge or side of the acromion segment 3 is chamfered to reduce friction or impact with the greater tuberosity of the humeral head 2, and the edge or side of the glenoid segment 5 is also chamfered, that is, the outer end of the acromion segment 3 is set as a corner structure to avoid friction or impact with the acromion 1 or surrounding tissues.

[0042] Preferably, the inner and outer sides of the connecting section 4 respectively have a front arc surface 41 and a rear arc surface 42 connected to each other, that is, the connecting section 4 is in an arc convex shape when viewed from the left and right sides, and the curvature radius of the front arc surface 41 is smaller than the curvature radius of the rear arc surface 42, that is, the front arc surface 41 is steeper, and the rear arc surface 42 is relatively gentle, and the front arc surface 41 is close to the lower surface of the acromion 1, so that part of the acromion 1 is just against the front arc surface 41 of the connecting section 4. Therefore, the stability of the prosthesis is improved, and the contact with the surrounding soft tissue is reduced, thereby reducing the stimulation to the soft tissue.

[0043] The surfaces of the acromion segment 3, the connection segment 4 and the glenoid segment 5 can be made of the same rigid material, or they can be solid as a whole and made of the same rigid material and connected to each other; or they can be made of layered materials in the upper and lower directions and connected to each other.

[0044] The rigid material may be one or more combinations of polyester, polyvinyl chloride, nylon, etc.

[0045] From a top view, the overall length of the prosthesis is about 51.6mm, the width is about 40.1, and the thickness is about 15.7mm. The maximum thickness of the connecting segment 4 is about 13mm, and the minimum thickness is about 11mm; the maximum thickness of the acromion segment 3 is 11mm, and the minimum thickness is 6.1mm; the maximum thickness of the glenoid segment 5 is about 10.4mm.

[0046] In this embodiment, the curved surfaces of the glenoid segment and the acromion segment can better fit the bone surface, the connecting portion is set to an arc shape to avoid contact with the anterior soft tissue and reduce stimulation, the upper surface of the acromion segment 3 is a microporous structure to promote bone ingrowth and increase long-term stability; the lower surface of the acromion segment 3 is highly polished to reduce the friction coefficient and reduce wear; the outer end of the acromion segment 3 is set to a corner design to reduce the impact of the prosthesis with the greater tuberosity.

[0047] Therefore, we use a rigid subacromial implant to restore the inherent stability of the glenohumeral joint. The function of this implant is similar to that of a subacromial balloon, in that it is a passive barrier that limits the upward movement of the humeral head. However, unlike a subacromial balloon, the implant is rigid and, through its special structural design, allows it to be safely and stably fixed to the scapula for a long time. This implant is particularly suitable for young, active patients with large, irreparable rotator cuff tears, providing a different treatment option from the existing ones, achieving the purpose of delaying joint replacement surgery and improving treatment outcomes.

[0048] The present utility model is not limited to the above-mentioned optimal implementation mode. Anyone can derive other various forms of products under the inspiration of the present utility model. However, no matter what changes are made in the shape or structure, all those having the same or similar technical solutions as the present application fall within the protection scope of the present utility model.

Claims

1. A subacromial implant prosthesis, for implantation between the acromion (1) and the humeral head (2), characterized in that: The invention comprises an acromion section (3) and a glenoid section (5) which are distributed inwardly and outwardly, wherein the glenoid section (5) has a lower surface adapted to the upper surface of the supraglenoid tubercle (72), and the glenoid section (5) is provided with a mounting through hole (51) arranged in the up-down direction, and the acromion section (3) has an upper surface adapted to the lower surface of the acromion (1), and the acromion section (3) also has a lower surface adapted to the surface of the humeral head (2).

2. A subacromial implant according to claim 1, characterized in that: The lower surface of the glenoid scapula segment (5) is in the form of a first porous grid structure (52) in the shape of trabeculae.

3. A subacromial implant according to claim 2, characterized in that: The upper surface of the acromion segment (3) is in the form of a second porous grid structure (31) in the shape of trabeculae.

4. A subacromial implant according to claim 3, characterized in that: The lower surface of the acromion segment (3) is an arc-shaped surface, and its curvature radius is greater than the curvature radius of the humeral head (2).

5. The subacromial implant according to claim 4, characterized in that: The lower surface of the shoulder segment (3) is smooth.

6. The subacromial implant according to claim 5, characterized in that: The lower surface of the shoulder section (3) is subjected to high polishing treatment.

7. The subacromial implant according to claim 6, characterized in that: The edge or side of the shoulder section (3) is chamfered.

8. The subacromial implant according to claim 1, characterized in that: It also includes a connecting section (4) connecting the acromion section (3) and the glenoid section (5).

9. The subacromial implant according to claim 8, characterized in that: The connecting section (4) has a front arc surface (41) and a rear arc surface (42) at the inner and outer sides respectively, and the curvature radius of the front arc surface (41) is smaller than the curvature radius of the rear arc surface (42).

10. The subacromial implant according to claim 8, characterized in that: The prosthesis as a whole or on its surface is made of rigid material.

Images