Rotary distraction type atlantoaxial lateral mass joint supporting fusion device

Abstract

The utility model relates to the technical field of medical instruments, in particular to a rotary opening type atlantoaxial lateral mass joint supporting fusion device. Comprising a supporting body, the supporting body is provided with four side faces which are sequentially connected end to end, the four side faces are two symmetrically-arranged insertion contact faces and two symmetrically-arranged supporting contact faces respectively, the head of the supporting body is in a triangular wedge shape, and the tail of the supporting body is detachably connected with a surgical operation handle; and the width of the insertion contact surface is gradually reduced from one end close to the head part to one end close to the tail part. According to the supporting fusion device, the width of the contact surface where the supporting body is inserted is gradually reduced from the end close to the head to the end close to the tail, when the supporting contact surface makes contact with the joint, the supporting body is in the state that the front end is high and the rear end is low, and the function of fixing the angle of the atlantoaxial lateral mass joint is achieved; the regulation and control of the atlantoaxial lateral mass joint fixing angle and the physiological fusion function are achieved through a minimally invasive surgery method.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, and in particular to a rotational opening type atlantoaxial lateral mass joint support and fusion device. Background Technology

[0002] Atlantoaxial dislocation is a high cervical spine disorder occurring at the craniocervical junction. Due to compression of the high cervical spinal cord, surgical treatment is often required. The surgical goal is to reposition and fix the atlantoaxial joint in a suitable anatomical position, relieve spinal cord compression, and restore the physiological curvature of the upper cervical spine. Currently, the commonly used surgical method employs a combination of posterior atlantoaxial screws and titanium rods or plates to form a fixation system, and implants bone blocks or fusion devices at the lateral mass joint to improve fixation and fusion outcomes. Studies have found that fixing the atlantoaxial joint at a certain physiological angle (5-20 degrees) helps maintain the physiological balance between the lower and upper cervical spine. Current commercially available fusion devices do not have the function of adjusting the atlantoaxial joint angle. Therefore, a lateral mass joint support device that can achieve atlantoaxial joint angle fixation and promote bone fusion is proposed. Utility Model Content

[0003] The purpose of this invention is to provide a rotational opening type atlantoaxial lateral mass joint support and fusion device. This support and fusion device can achieve physiological angle fixation and fusion of the atlantoaxial lateral mass joint, thereby improving the physiological balance of the lower and upper cervical vertebrae and achieving better surgical results.

[0004] This utility model provides a rotary-spreading atlantoaxial lateral mass joint support fusion device, including a support body. The support body has four sides connected end to end in sequence, namely two symmetrically arranged insertion contact surfaces and two symmetrically arranged support contact surfaces. The head of the support body is triangular wedge-shaped, and the tail of the support body is detachably connected to the surgical operating handle. The width of the insertion contact surface gradually decreases from the end near the head to the end near the tail.

[0005] Furthermore, the tail of the support body is provided with a threaded groove, and the tail of the support body is symmetrically provided with two slots, which are respectively located on the insertion contact surface.

[0006] Furthermore, the two insertion contact surfaces are parallel to each other.

[0007] Furthermore, one of the supporting contact surfaces is inclined upwards at 2.5-10 degrees relative to the horizontal line, and the other supporting contact surface is inclined downwards at 2.5-10 degrees relative to the horizontal line, with the two supporting contact surfaces inclining at the same angle.

[0008] Furthermore, the insertion contact surface is a smooth plane, while the support contact surface is a rough surface.

[0009] Furthermore, the supporting contact surface is serrated.

[0010] Furthermore, the width of the insertion contact surface is 4-10 mm, and the width of the support contact surface is 5-6 mm.

[0011] Furthermore, the support is made of one of titanium, tantalum, or a titanium-tantalum composite material, and the support has a porous structure that mimics human cancellous bone.

[0012] Furthermore, the material of the support is allogeneic bone or polyetheretherketone.

[0013] Furthermore, all sides of the head of the support are smooth surfaces.

[0014] In summary, this utility model has the following advantages:

[0015] The support fusion device provided by this utility model includes a support body with two symmetrical insertion contact surfaces and two support contact surfaces. When the support body is connected to the surgical handle and implanted into the atlantoaxial lateral mass joint, its insertion contact surfaces correspond to the upper and lower articular surfaces of the atlantoaxial lateral mass joint, respectively. After the support body is fully inserted into the lateral mass joint space, the support body is rotated 90 degrees so that the support contact surfaces contact the joint, and the support body enters the working state. The head of the support body is designed in the shape of a triangular wedge, which can facilitate its insertion into the lateral mass joint space. The width of the insertion contact surface gradually decreases from the end near the head to the end near the tail. When the support contact surfaces contact the joint, the support body presents a state where the front end is higher and the rear end is lower, realizing the function of fixing the angle of the atlantoaxial lateral mass joint. The atlantoaxial lateral mass joint fixation angle is controlled and the physiological fusion function is achieved through minimally invasive surgical methods. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the supporting fusion device in an embodiment of the present invention;

[0018] Figure 2 This is a structural schematic diagram of the supporting fusion device from another angle in an embodiment of this utility model;

[0019] Figure 3This is a schematic diagram illustrating the process of implanting the fusion support device into the atlantoaxial lateral mass joint in an embodiment of this utility model.

[0020] Figure 4 This is a schematic diagram of the structure of the support fusion device after it is implanted into the atlantoaxial lateral mass joint in an embodiment of this utility model;

[0021] Figure 5 This is a schematic diagram of the structure of the support fusion device implanted at the anterior end of the atlantoaxial lateral mass joint in an embodiment of this utility model.

[0022] Explanation of reference numerals in the attached diagram: 1-Support body; 2-Insertion contact surface; 3-Support contact surface; 4-Head; 5-Slot; 6-Lateral mass of atlas; 7-Axis; 8-Surgical operating handle. Detailed Implementation

[0023] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0024] In the description of this utility model, 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", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to 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 this utility model.

[0025] 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, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" 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 or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0026] Example

[0027] A rotational expansion type atlantoaxial lateral mass joint support fusion device, such as Figure 1 and Figure 2 As shown, it includes a support body 1, which is approximately elongated and has an axisymmetric structure. It has four sides connected end to end, namely two symmetrically arranged insertion contact surfaces 2 and two symmetrically arranged support contact surfaces 3. The head 4 of the support body 1 is triangular wedge-shaped, and all sides of the head 4 are smooth surfaces. The tail of the support body 1 is detachably connected to the surgical handle. The width of the insertion contact surface 2 gradually decreases from the end near the head 4 to the end near the tail.

[0028] The support body 1 has a threaded groove inside its tail end, and two symmetrical retaining slots 5 are also provided at the tail end of the support body 1. The two retaining slots 5 are located on the insertion contact surface 2, and the retaining slots 5 are arc-shaped. When the support body 1 is implanted, the surgical operating handle is threadedly connected to the threaded groove at the tail end of the support body 1, and the two jaws on the surgical operating handle are engaged in the retaining slots 5 to connect and fix the support body 1 and the surgical operating handle.

[0029] The insertion contact surface 2 is a smooth plane, and the two insertion contact surfaces 2 are parallel to each other. The width of the insertion contact surface 2 is 4-10mm, and the width gradually decreases from the end near the head 4 to the end near the tail. This makes the supporting working state after the support body 1 is implanted present as a state where the front end is high and the rear end is low, thereby fixing the angle between the upper and lower articular surfaces of the atlantoaxial lateral mass joint. This is very helpful for patients with basilar impression to restore the physiological cranial angle.

[0030] The support contact surface 3 is a rough surface, with a serrated shape. Essentially, the support contact surface 3 is formed by machining serrations onto a smooth plane. It can also be designed with other rough shapes to increase friction with the superior and inferior articular surfaces of the atlantoaxial lateral mass joint, while simultaneously inducing bone fusion with the support body 1. Bone cells can grow along the concave and convex areas of the serrations. Compared to a planar structure, this increases the effective contact area between the bone and the support body 1, making bone ingrowth into the support body 1 more favorable. The width of the support contact surface 3 is 5-6 mm. This width is smaller than the width of the insertion contact surface 2, essentially meaning the implantation height of the support body 1 is slightly less than the support height, making it easier for the support body 1 to insert into the gap between the atlantoaxial lateral mass joints, even if the lateral mass joint gap is small.

[0031] The width of the insertion contact surface 2 gradually decreases from the end near the head 4 to the end near the tail. When the support body 1 enters the support working state, the two support contact surfaces 3 are tilted with the front end higher than the rear end. The upper support contact surface 3 is tilted downwards at 2.5-10 degrees relative to the horizontal line, and the lower support contact surface 3 is tilted upwards at 2.5-10 degrees relative to the horizontal line. The tilt angles of the two support contact surfaces 3 are the same.

[0032] The support 1 provided by this invention is small in size and does not have a specially designed bone window to accommodate autologous bone. It is manufactured using titanium or tantalum metal powder as raw material and employs metal 3D printing technology. Its internal structure mimics the porous structure of human cancellous bone, which not only provides support between the atlantoaxial lateral mass joints but also induces bone ingrowth into the porous structure of the support 1, achieving bony fusion. During manufacturing, the tilt angle of the two support contact surfaces 3 can be set according to the patient's specific condition. Furthermore, after the support 1 is implanted, autologous bone, allogeneic bone, or osteoinductive materials can be implanted in the space surrounding the support 1 to promote bony fusion of the atlantoaxial lateral mass joint.

[0033] Support 1 can also be made of titanium-tantalum composite material, or it can be made of materials such as allogeneic bone or polyetheretherketone.

[0034] The method of using the support fusion device provided by this utility model is as follows: First, insert the surgical operating handle 8 into the threaded groove and thread it to the support body 1. Then, lock the two claws on the surgical operating handle 8 into the slot 5. After fixing the support body 1 and the surgical operating handle 8, insert the head 4 of the support body 1 into the gap between the atlantoaxial lateral mass 6 and the axis 7 joint with the support contact surface 3 perpendicular to the horizontal plane. Use a special hammer or striking device to strike the surgical operating handle to drive the support body 1 into the gap between the atlantoaxial lateral mass 6 and the axis 7 joint (e.g., ...). Figure 3 As shown), after the support body 1 is fully inserted into the lateral mass joint space, the surgical operating handle 8 is rotated 90 degrees to rotate the support body 1 90 degrees, so that the two support contact surfaces 3 contact the inferior articular surface of the atlas lateral mass 6 and the superior articular surface of the axis 7 respectively, thus entering the support working state (as shown). Figure 4 and Figure 5 (As shown), finally remove the surgical handle 8 from the support 1.

[0035] Implanting a simple anteriorly higher than posteriorly support in clinical surgery is extremely difficult. The support provided by this invention has a unique shape and structure, employing a unique 90-degree rotational expansion design. This allows for the implantation of a 3D-printed support with anteriorly higher than posteriorly lower dimensions into the narrow atlantoaxial lateral mass space, overcoming the difficulty of implanting supports with unequal anterior and posterior heights. This achieves physiological angle fixation and fusion of the atlantoaxial lateral mass joint, thereby improving the physiological balance of the lower and upper cervical vertebrae and obtaining better surgical results.

[0036] Because most patients with basilar impression also have atlanto-occipital ossification and atlanto-lateral mass joint deformity, after posterior surgery to reposition the odontoid process of the axis, the atlanto-lateral mass joint often fails to restore its normal anatomical alignment. It cannot achieve the effective inter-articular contact and support seen in normal individuals. Consequently, most of the mechanical load from the skull is transmitted through the posterior screws and titanium rods. In the early postoperative period, excessive load on the screws and titanium rods (plates) may lead to internal fixation failure, such as premature rod breakage. The support provided by this invention, with its high front and low rear end, can transmit the mechanical load from the skull anteriorly, thereby dispersing posterior stress and reducing the incidence of internal fixation loosening and failure. Furthermore, its unique rotational design effectively adjusts the alignment and angle of the atlanto-axial lateral mass joint, correcting the craniovertebral angle in basilar impression patients and aiding in the fusion of the atlanto-axial lateral mass joint.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A rotational, distraction-type atlantoaxial lateral mass joint support fusion device, comprising: The support body (1) is provided with four side surfaces connected in sequence, two symmetrically arranged insertion contact surfaces (2) and two symmetrically arranged support contact surfaces (3), the head (4) of the support body (1) is in the shape of a triangular wedge, and the tail of the support body (1) is detachably connected with a surgical operation handle; the width of the insertion contact surface (2) gradually decreases from one end close to the head (4) to one end close to the tail.

2. The rotatable, distractible lateral mass articulating support fusion device of Claim 1, wherein, The tail of the support body (1) is provided with a threaded groove, and the tail of the support body (1) is symmetrically provided with two clamping grooves (5), and the two clamping grooves (5) are respectively located on the insertion contact surface (2).

3. The rotatorially distracting lateral mass articulating fusion device for the atlantoaxial spine according to claim 1, wherein, The two insertion contact surfaces (2) are parallel to each other.

4. The rotatorially distracting lateral mass articulating fusion device of the C-l-C2 spine of Claim 1 wherein, One of the support contact surfaces (3) is inclined upward by 2.5-10 degrees relative to the horizontal line, and the other support contact surface (3) is inclined downward by 2.5-10 degrees relative to the horizontal line, and the angles of inclination of the two support contact surfaces (3) are the same.

5. The rotatorially distracting Cervico-Axis Pedicle-Joint Support Fusion device according to claim 1, wherein, The insertion contact surface (2) is a smooth plane, and the support contact surface (3) is a rough surface.

6. The rotatorially distracting Cervico-Axis Pedicle-Joint Support Fusion device, according to claim 5, wherein, The support contact surface (3) is in the shape of a sawtooth.

7. The rotatorially distracting Cervico-Axis Pedicle-Joint Support Fusion device, according to claim 1, wherein, The width of the insertion contact surface (2) is 4-10 mm, and the width of the support contact surface (3) is 5-6 mm.

8. The rotary pedicle screw Cervico-Axial Lateral Mass Joint Support Fusion device of claim 1 wherein, The material of the support body (1) is one of titanium metal, tantalum metal or titanium-tantalum composite material, and the support body (1) is a porous structure simulating human cancellous bone.

9. The rotary pedicle screw Cervico-Axial Lateral Mass Joint Support Fusion device of claim 1 wherein, The material of the support body (1) is allogeneic bone or polyether ether ketone.

10. The rotary pedicle screw Cervico-Axial Lateral Mass Joint Support Fusion device of claim 1 wherein, All the side surfaces of the head (4) of the support body (1) are smooth surfaces.

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