Glenoid cavity navigator for reverse full shoulder joint replacement

Abstract

The utility model relates to a glenoid cavity navigator for reverse type full shoulder joint replacement. The glenoid cavity navigator comprises a main shaft, a handle, a front locking nut, a rear locking nut and five positioning supports. Scales on the surface of the spindle are used for adjusting the position of the positioning bracket; a Kirschner wire is inserted into the central duct to position the prosthesis; the handle accords with ergonomics and is antiskid, and is detachably connected with one end of the main shaft through a rear locking nut; the positioning supports are different in model and accord with the glenoid cavity anatomical structure, the ends of the positioning supports are arranged between the handle and the main shaft and are screwed and locked through rotation of the front locking nut, and marks are arranged on the surfaces of the positioning supports. Compared with the prior art, the navigator adjusts the scales of the positioning support according to the plan before the operation, is fixed to the glenoid cavity during the operation, guides the follow-up operation, ensures that the implant angle of the prosthesis is consistent with the plan before the operation, effectively solves the problem that the implant angle of the glenoid cavity prosthesis is accurately controlled, reduces the risk of complications, and improves the success rate and efficiency of the operation; the postoperative shoulder function recovery of the patient is ensured.

Description

Technical Field

[0001] This utility model relates to a glenoid navigator, and more particularly to a glenoid navigator for reverse total shoulder arthroplasty. Background Technology

[0002] In modern orthopedic medicine, reverse total shoulder arthroplasty (rTSA) has become an important treatment for various shoulder conditions, with its application expanding to include rotator cuff injuries, proximal humeral fractures, humeral head necrosis, osteoarthritis, large rotator cuff tears, and proximal humeral tumors. Compared to traditional anatomical total shoulder arthroplasty (aTSA), rTSA demonstrates advantages in postoperative shoulder pain relief and shoulder joint range of motion, and it does not rely on the integrity of the rotator cuff muscles. Therefore, it is increasingly favored by clinicians and is being used more widely.

[0003] However, despite the numerous advantages of rTSA, some patients still experience serious complications post-surgery, significantly impacting their quality of life and the overall surgical outcome. Clinical studies have shown that improper glenoid prosthesis placement is a key factor leading to surgical failure. The anterior and posterior bones of the scapula are relatively thin; when the glenoid prosthesis is misaligned, it can easily lead to scapular bone destruction, prosthesis loosening, and other adverse consequences. Furthermore, it may negatively affect humeral stability and joint mobility, ultimately resulting in severely limited shoulder joint function post-surgery.

[0004] During the surgery, various factors make it difficult for surgeons to accurately locate the glenoid prosthesis. On the one hand, the intraoperative field of vision is limited, and the visible range of the surgical area is restricted, making it difficult to fully and clearly observe the anatomical details of the glenoid. On the other hand, the anatomical structure of the shoulder is complex and variable, with certain individual differences among patients, and bony landmarks are not obvious and are limited. This poses a great challenge to surgeons in determining the accurate placement and angle of the glenoid prosthesis.

[0005] With the rapid development of computer technology, preoperative planning systems have emerged and are gradually being applied in clinical practice. Using the rTSA preoperative planning system, surgeons can perform three-dimensional reconstruction of the bony structure of the patient's shoulder joint, simulate the prosthesis implantation position preoperatively, and obtain the most suitable glenoid prosthesis implantation angle. Although this technology provides important reference for surgery to a certain extent, in actual surgical operations, due to the lack of effective intraoperative navigation tools, it is still difficult to avoid errors in glenoid angle measurement caused by various factors. This results in a still relatively high risk of prosthesis implantation failure, seriously affecting the efficacy of the surgery and the patient's prognosis.

[0006] In summary, ensuring the precision of glenoid prosthesis implantation angle in reverse total shoulder arthroplasty has become a critical issue that urgently needs to be addressed. Solving this problem is crucial for improving the success rate of rTSA surgery, reducing the incidence of complications, and improving patients' postoperative quality of life. It is against this backdrop that this invention aims to provide a glenoid navigator for reverse total shoulder arthroplasty to fill this clinical gap and effectively solve the problem of accurately controlling the glenoid prosthesis implantation angle. Utility Model Content

[0007] The purpose of this invention is to overcome the defects of the prior art and provide a glenoid navigator for reverse total shoulder arthroplasty, which effectively solves the problem of the difficulty in accurately controlling the glenoid prosthesis implantation angle in reverse total shoulder arthroplasty.

[0008] The objective of this utility model can be achieved through the following technical solutions:

[0009] This utility model provides a glenoid navigator for reverse total shoulder arthroplasty, including a main shaft, a handle, a front locking nut, and multiple positioning brackets;

[0010] The main shaft surface is provided with a scale, the smallest scale is used to adjust the position of the positioning bracket along the main shaft axis, and an axial channel is provided in the center of the main shaft, the axial channel is used to insert Kirschner wires to position the glenoid prosthesis.

[0011] The handle is detachably connected to one end of the spindle;

[0012] Multiple positioning brackets are designed to match the normal anatomical structure of the human glenoid cavity. The positioning brackets are detachably mounted on the outer surface of the spindle. One end of the positioning bracket is placed between the handle and the surface of the spindle and can be locked by rotating the front locking nut. The positioning bracket can be moved along the axial direction of the spindle to adjust its position and locked by the front locking nut.

[0013] Furthermore, the outer surface of the spindle is provided with multiple positioning grooves, and the positioning bracket is disposed in the positioning grooves.

[0014] Furthermore, the end of the handle is provided with an outwardly extending pressure plate, which presses against one end of the positioning bracket to form an interference fit.

[0015] Furthermore, the front locking nut includes a pressing section near the pressure plate and an internal thread section screwed to the end of the handle. When the front locking nut rotates toward the pressure plate, the pressing section presses against the pressure plate, so that the positioning bracket is clamped between the spindle surface and the pressure plate, thereby locking the positioning bracket.

[0016] Furthermore, when the front locking nut rotates toward the side away from the pressure plate, the clamping force on the pressure plate decreases, thereby unlocking the positioning bracket. This allows the positioning bracket to slide and adjust along the positioning groove and to be aligned with the scale on the spindle surface.

[0017] Furthermore, one end of each of the multiple different models of positioning brackets corresponds to a different model of finger support, thereby classifying the different models of positioning brackets into positioning bracket A, positioning bracket B, positioning bracket C, positioning bracket D, and positioning bracket E.

[0018] Furthermore, when the front locking nut is tightened, positioning bracket A and positioning bracket E can be placed on the upper front edge and lower front edge of the glenoid cavity, respectively, while positioning brackets B, C, and D are placed on the glenoid cavity surface, thus properly fixing the navigator.

[0019] Furthermore, the diameter of the axial channel at the center of the main shaft is 1 to 3 mm.

[0020] Furthermore, the handle is detachably connected to one end of the spindle via a rear locking nut.

[0021] Furthermore, the handle is provided with an anti-slip texture;

[0022] Furthermore, the surface of the positioning bracket is marked to enable quick and accurate identification and adjustment of its position during surgery, ensuring consistency with preoperative planning.

[0023] Furthermore, the rear locking nut is located at the end of the handle away from the front locking nut.

[0024] Furthermore, the handle has a hollow tube structure, the end of the spindle is placed in the handle, and the rear locking nut is screwed to the handle, such that the rear locking nut abuts against the end of the spindle.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] This invention effectively solves the problem of accurately controlling the glenoid prosthesis implantation angle during reverse total shoulder arthroplasty through a sophisticated structural design consisting of a main shaft, handle, front locking nut, rear locking nut, and five positioning brackets conforming to the anatomical structure of the human glenoid cavity. By utilizing a preoperative planning system combined with the precise scale of the navigator and the adjustment function of the positioning brackets, it can ensure that the glenoid prosthesis implantation angle during surgery is highly consistent with the preoperative plan, greatly reducing the risk of complications such as scapular bone destruction, prosthesis loosening, and limited joint movement caused by errors in the prosthesis implantation angle. Attached Figure Description

[0027] Figure 1 This is a three-dimensional structural diagram of the glenoid navigator used in reverse total shoulder arthroplasty according to this utility model;

[0028] Figure 2 This is a cross-sectional structural diagram of the glenoid navigator used in reverse total shoulder arthroplasty according to this utility model;

[0029] Figure 3 This is a schematic diagram of the main shaft in this utility model;

[0030] Figure 4 This is a schematic diagram of the structure of one of the positioning brackets in this utility model;

[0031] Figure 5 This is a schematic diagram of the handle structure in this utility model;

[0032] Figure 6 This is a physical example drawing showing the width of the end of the positioning bracket in this utility model. Detailed Implementation

[0033] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Component models, material names, connection structures, control methods, algorithms, and other features not explicitly described in this technical solution are considered common technical features disclosed in the prior art.

[0034] Example 1

[0035] This embodiment provides a glenoid navigator for reverse total shoulder arthroplasty, including a main shaft 1, a handle 2, a front locking nut 4, and multiple positioning brackets 3 of different or identical models. See details below. Figures 1 to 5 .

[0036] The main spindle 1 has a scale on its surface, the smallest scale of which is used to adjust the position of the positioning bracket along the axial direction of the main spindle 1, and an axial channel is opened in the center of the main spindle. The axial channel is used to insert Kirschner wires to position the glenoid prosthesis. The outer surface of the main spindle 1 has multiple positioning grooves, and the positioning bracket 3 is located in the positioning grooves.

[0037] The handle 2 is detachably connected to one end of the spindle 1. The end of the handle 2 is provided with an outwardly extending pressure plate 5, which presses against one end of the positioning bracket 3 to form an interference fit.

[0038] Multiple positioning brackets 3 of different or the same model are used to match the normal anatomical structure of the human glenoid cavity. The positioning bracket 3 is detachably mounted on the outer surface of the main shaft 1. One end of the positioning bracket 3 is placed between the handle 2 and the surface of the main shaft 1 and can be locked by rotating the front locking nut 4. The positioning bracket 3 can be moved along the axial direction of the main shaft to adjust its position and locked by the front locking nut 4.

[0039] The front locking nut 4 includes a pressing section 41 near the pressure plate 5 and an internally threaded section 42 screwed to the end of the handle 2. When the front locking nut 4 rotates toward the pressure plate 5, the pressing section 41 abuts against the pressure plate 5, clamping the positioning bracket 3 between the surface of the spindle 1 and the pressure plate 5, thus locking the positioning bracket 3. When the front locking nut 4 rotates toward the side away from the pressure plate 5, the clamping force on the pressure plate 5 decreases, unlocking the positioning bracket 3. This allows the positioning bracket 3 to slide and adjust along the positioning groove and to be aligned with the scale on the surface of the spindle 1.

[0040] One end of each of the multiple different models of positioning brackets 3 corresponds to a different model of finger support part, thereby dividing the different models of positioning brackets 3 into positioning bracket A, positioning bracket B, positioning bracket C, positioning bracket D, and positioning bracket E.

[0041] When the front locking nut 4 is tightened, positioning brackets A and E can be placed on the upper front edge and lower front edge of the glenoid cavity, respectively, and positioning brackets B, C and D can be placed on the glenoid cavity surface, so that the navigator can be properly fixed.

[0042] The diameter of the axial channel in the center of the spindle is 1-3 mm. The handle 2 is detachably connected to one end of the spindle via a rear locking nut 6. The handle 2 has anti-slip textures; the surface of the positioning bracket 3 is marked for quick and accurate identification and adjustment of its position during surgery, ensuring consistency with preoperative planning. The rear locking nut 6 is located at the end of the handle 2 furthest from the front locking nut 4. The handle 2 has a hollow tube structure, with the end of the spindle 1 placed within the handle 2. The rear locking nut 6 is screwed onto the handle 2, abutting against the end of the spindle 1.

[0043] The following is a detailed process of how the various components of this utility model work together to achieve beneficial effects:

[0044] Synergistic effect of spindle 1 and other components:

[0045] The coordination of the scale and positioning bracket 3: The surface of the main shaft 1 is equipped with precise scales. Before surgery, the surgeon, based on the optimal implantation angle of the glenoid prosthesis determined by the preoperative planning system, precisely adjusts the position of the positioning bracket 3 by referring to the scale on the main shaft 1. For example, positioning brackets A and E are placed at the anterior upper edge and anterior lower edge of the glenoid, respectively, while positioning brackets B, C, and D are placed on the glenoid surface. The relative position adjustment of different positioning brackets 3 on the main shaft 1 is the basis for achieving precise angle control. Due to the presence of the scale, the surgeon can move the positioning bracket 3 with millimeter-level precision, ensuring that the angle determined by the combination of positioning brackets 3 is consistent with the preoperative plan, thereby providing an accurate angle reference for glenoid prosthesis implantation and effectively avoiding complications caused by angle errors.

[0046] The axial channel and Kirschner wire connection: The axial channel in the center of spindle 1 is used to insert Kirschner wires, with a diameter of 1-3mm. This size ensures stable insertion of the Kirschner wires and allows them to enter the glenoid cavity precisely along the predetermined direction, providing accurate starting direction guidance for subsequent osteotomy, drilling, and prosthesis implantation. After the positioning bracket 3 is adjusted to the position according to the scale of spindle 1, the Kirschner wire is inserted into the glenoid cavity through the axial channel, allowing subsequent surgical operations to be performed closely around the pre-planned angle, further ensuring the accuracy of the glenoid prosthesis implantation angle and reducing surgical risks.

[0047] The cooperation between the positioning groove and the positioning bracket 3: Multiple positioning grooves on the outer surface of the main shaft 1 provide a stable mounting track for the positioning bracket 3, ensuring that the positioning bracket 3 is positioned more accurately and stably on the main shaft 1. The positioning bracket 3 is installed in the positioning groove, and is less prone to displacement or rotation when subjected to external forces such as collisions or traction during surgery. This ensures the stability of the glenoid prosthesis implantation angle determined by the positioning bracket 3, allowing the surgical procedure to be performed more precisely according to the preoperative plan and reducing angular errors caused by changes in the position of the positioning bracket 3.

[0048] The synergistic effect of handle 2 with other components:

[0049] Connection stability with spindle 1: Handle 2 is detachably connected to one end of spindle 1 via a rear locking nut 6. The rear locking nut 6 is screwed onto handle 2 and abuts against the end of spindle 1, forming a stable integral structure between handle 2 and spindle 1. This connection method ensures that there will be no loosening or displacement between handle 2 and spindle 1 during surgical operations. When the surgeon operates the navigator through handle 2, the hand movements can be accurately transmitted to spindle 1 and positioning bracket 3, ensuring the structural stability of the entire navigator and contributing to precise surgical operations and accurate implantation of the glenoid prosthesis.

[0050] Anti-slip texture and ease of operation: The handle 2 features an anti-slip texture, which makes it more stable and comfortable for the surgeon to hold, reducing the possibility of hand slippage. During surgery, especially when adjusting the position of the positioning bracket 3 and fixing the navigator to the glenoid surface, the anti-slip handle 2 allows the surgeon to more precisely control the movement and placement angle of the navigator, ensuring that the positioning bracket 3 accurately conforms to the anatomical structure of the glenoid, improving the precision and efficiency of the surgical operation, and thus ensuring the accuracy of the glenoid prosthesis implantation angle.

[0051] The engagement between the pressure plate 5 and the positioning bracket 3: The pressure plate 5 at the end of the handle 2 presses against one end of the positioning bracket 3 to form an interference fit. Under the action of the front locking nut 4, the pressure between the pressure plate 5 and the positioning bracket 3 can further fix the position of the positioning bracket 3. When the front locking nut 4 is tightened, the pressing section 41 presses against the pressure plate 5, so that the positioning bracket 3 is clamped between the surface of the main shaft 1 and the pressure plate 5, effectively preventing the positioning bracket 3 from shifting during the operation, ensuring the stability of the glenoid prosthesis implantation angle determined by the positioning bracket 3, and reducing the risk of surgical errors caused by the movement of the positioning bracket 3.

[0052] In practical implementation, the width of the three ends of the positioning bracket is a key factor in model classification. (See [link to relevant documentation]). Figure 6 The corresponding positioning brackets 3 have end widths of 19mm, 12mm, 14mm, 15mm, and 16mm, respectively, which can be used to position the navigator at the center of the glenoid cavity of different patients.

[0053] The synergistic effect of the front locking nut 4 with other components:

[0054] The locking mechanism for the positioning bracket 3: The front locking nut 4 includes a pressing section 41 and an internal thread section 42. When rotated towards the pressure plate 5, the pressing section 41 presses against the pressure plate 5, clamping and fixing the positioning bracket 3. This locking method converts the rotational motion of the thread into pressure on the positioning bracket 3, firmly fixing the positioning bracket 3 to the main shaft 1 and preventing displacement or angular changes due to external forces during surgery. During surgery, once the positioning bracket 3 is adjusted to its position according to the preoperative plan, the front locking nut 4 can reliably maintain its position, ensuring the accuracy of the glenoid prosthesis implantation angle, effectively avoiding angular errors caused by loosening of the positioning bracket 3, and ensuring the safety and success rate of the surgery.

[0055] Convenience of unlocking the positioning bracket 3: When the forward locking nut 4 is rotated away from the pressure plate 5, the clamping force on the pressure plate 5 decreases, thus unlocking the positioning bracket 3. At this time, the positioning bracket 3 can slide and adjust along the positioning groove and can be aligned with the scale on the surface of the main shaft 1. This flexible locking and unlocking mechanism allows the doctor to accurately adjust the position of the positioning bracket 3 during surgery according to the preoperative planning data. During the adjustment process, the doctor can easily move the positioning bracket 3 and then lock it again with the forward locking nut 4 to ensure that the positioning bracket 3 is always in the optimal position so that the glenoid prosthesis implantation angle is consistent with the preoperative planned height.

[0056] Synergistic effect among the five positioning brackets 3:

[0057] Anatomically Conforming Multi-Point Support: Five positioning supports (A, B, C, D, and E) each have different types of finger-shaped support parts. These supports are designed to precisely match the normal anatomical structure of the glenoid cavity, providing support and angle control from multiple key locations within the cavity. For example, positioning supports A and E are used for positioning and angle adjustment at the anterosuperior and anteroinferior edges of the glenoid cavity, respectively, while positioning supports B, C, and D provide finer angle control and stability support within the glenoid cavity. They work together to form a stable multi-point support structure that closely and accurately conforms to the complex curved shape of the glenoid cavity. This provides a precise angular reference for glenoid prosthesis implantation, significantly reducing the risk of complications such as scapular bone destruction, prosthesis loosening, and limited joint movement caused by implantation angle errors. This improves surgical success rates and postoperative shoulder function recovery.

[0058] The markings and operational accuracy of the positioning brackets 3: The surface of the positioning brackets 3 is marked, allowing the surgeon to quickly and accurately identify and adjust the position of each positioning bracket 3 during surgery, ensuring consistency with the preoperative plan. This marking design facilitates the surgeon's rapid location and operation of specific positioning brackets 3 in the stressful surgical environment, improving the efficiency and accuracy of the surgical procedure. It also helps to achieve precise control of the glenoid prosthesis implantation angle, further ensuring the smooth progress of the surgery and a good surgical outcome.

[0059] It is evident that through the close and coordinated cooperation among the above components, the glenoid navigator of this utility model fully leverages the advantages of its structural design. Combined with the preoperative planning system, it effectively solves the problem of accurately controlling the glenoid prosthesis implantation angle during reverse total shoulder arthroplasty, providing strong support and guarantee for the successful implementation of the surgery and the good prognosis of the patient.

[0060] The above description of the embodiments is provided to enable those skilled in the art to understand and use the utility model. It will be apparent to those skilled in the art that various modifications can be easily made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present utility model is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present utility model without departing from its scope should be within the protection scope of the present utility model.

Claims

1. A glenoid navigator for a reverse total shoulder arthroplasty, characterized in that, It comprises a main shaft (1), a handle (2), a front locking nut (4), and a plurality of positioning supports (3). The main shaft (1) is provided with a scale on its surface, wherein the smallest scale is used to adjust the position of the positioning supports along the axial direction of the main shaft (1), and an axial hole is formed in the center of the main shaft, which is used to insert a Kirschner wire to position the glenoid prosthesis. The handle (2) is detachably connected to one end of the main shaft (1). The end of the plurality of positioning supports (3) is used to match the normal anatomical structure of the human glenoid, and the positioning supports (3) are detachably arranged on the outer surface of the main shaft (1). One end of the positioning supports (3) is arranged between the handle (2) and the surface of the main shaft (1), and can be locked by rotating and screwing the front locking nut (4). The positioning supports (3) are moved along the axial direction of the main shaft to adjust the position and are locked by the front locking nut (4).

2. A glenoid navigator for a reverse total shoulder arthroplasty according to claim 1, wherein, The outer surface of the main shaft (1) is provided with a plurality of positioning grooves, and the positioning supports (3) are arranged in the positioning grooves.

3. A glenoid navigator for a reverse total shoulder arthroplasty according to claim 2, wherein, The end of the handle (2) is provided with an outwardly extending pressing plate (5), which is pressed on one end of the positioning support (3) to form an interference fit.

4. A glenoid navigator for a reverse total shoulder arthroplasty as recited in claim 3, wherein, The front locking nut (4) comprises a pressing section (41) near the side of the pressing plate (5) and an internal thread section (42) screwed with the end of the handle (2). When the front locking nut (4) is rotated towards the side of the pressing plate (5), the pressing section (41) is tightly pressed on the pressing plate (5), so that the positioning support (3) is clamped between the surface of the main shaft (1) and the pressing plate (5), and the locking of the positioning support (3) is realized.

5. A glenoid navigator for a reverse total shoulder arthroplasty as defined in claim 4, wherein, When the front locking nut (4) is rotated away from the side of the pressing plate (5), the pressing force on the pressing plate (5) is reduced, the positioning support (3) is unlocked, the positioning support (3) can be adjusted by sliding along the positioning groove, and the alignment can be performed by referring to the scale on the surface of the main shaft (1).

6. A glenoid navigator for a reverse total shoulder arthroplasty as recited in claim 1, wherein, The ends of a plurality of positioning supports (3) of different models correspond to different model finger-shaped support parts, so that the positioning supports (3) of different models are divided into positioning support A, positioning support B, positioning support C, positioning support D and positioning support E.

7. A glenoid navigator for a reverse total shoulder arthroplasty according to claim 6, wherein, When the front locking nut (4) is tightened, the positioning support A and the positioning support E can be respectively arranged on the upper and lower front edges of the glenoid, and the positioning support B, the positioning support C and the positioning support D are arranged on the surface of the glenoid, so that the navigator is properly fixed.

8. A glenoid navigator for a reverse total shoulder arthroplasty as recited in claim 1, wherein, The diameter of the axial hole in the center of the main shaft is 1-3 mm.

9. A glenoid navigator for a reverse total shoulder arthroplasty as recited in claim 1, wherein, The handle (2) is detachably connected to one end of the main shaft by a rear locking nut (6). The handle (2) is provided with anti-slip texture.

10. A glenoid navigator for a reverse total shoulder arthroplasty as defined in claim 9, wherein, The rear locking nut (6) is arranged at the end of the handle (2) away from the front locking nut (4). The handle (2) is a hollow tube structure, the end of the main shaft (1) is arranged in the handle (2), the rear locking nut (6) is screwed with the handle (2), and the rear locking nut (6) abuts against the end of the main shaft (1).

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