Skull nail for stereotactic positioning

Abstract

The utility model provides a skull nail for stereotactic positioning. The skull nail comprises an implantation end part which is provided with a thread and is provided with a tip end, and the implantation end part is used for being drilled into a skull in a self-tapping mode and is in threaded connection with the skull; a tool engaging portion configured to engage with a driving tool to receive a rotational driving force from the driving tool, where the tool engaging portion is provided with a probe engaging portion for receiving a probe of a robot, the probe engaging portion being dimensioned so that the probe does not accidentally disengage from the probe engaging portion; and the connecting part connects the implanting end part with the tool joint part or is integrally formed with the implanting end part and the tool joint part, so that the implanting end part, the tool joint part and the connecting part are arranged along a straight line, and the axis of the skull nail is defined. By means of the skull nail for stereotactic positioning, the purposes of being convenient to implant and small in wound can be achieved, and the requirement for nuclear magnetic examination of a patient before an operation can be met.

Description

Technical Field

[0001] The utility model relates to a medical device, in particular to a medical device used for assisting stereoscopic positioning during an operation (especially a brain operation). Background Art

[0002] Nowadays, robots are increasingly used in brain surgery and play an increasingly important role. During surgery, robots can help doctors complete surgical plans more conveniently and provide accurate positioning and navigation, thereby assisting doctors in successfully completing brain surgery operations that require high precision. In order to operate the robot more precisely, the patient's position in the real world must be correctly located before the operation begins, and the patient's exact position must be accurately registered in the robot's data system. It can be seen that the above-mentioned precise positioning is crucial for the successful implementation of brain surgery using robots.

[0003] At present, the methods of robot positioning patients mainly include visual positioning, positioning frame positioning and stereoscopic positioning of skull pins. Among these three positioning methods, the accuracy of visual positioning is relatively low, and it is usually difficult to meet the data accuracy requirements of robotic surgery. The accuracy of positioning frame positioning is significantly improved compared with visual positioning, but the positioning frame device used is relatively bulky, which directly limits the applicable surgical population, and the existence of the positioning frame device may lead to the creation of surgical blind spots, which directly affects the implementation of the operation.

[0004] In contrast, the positioning achieved by using skull pins for stereotaxic positioning is more accurate, and is therefore generally chosen by doctors. However, the skull pins currently used are inconvenient to implant due to their structural defects, and the wound after implantation is large. In addition, the choice of manufacturing materials may interfere with the patient's preoperative MRI examination.

[0005] Therefore, a skull nail which is easy to implant, has a small incision and is made of a specific material is needed to solve the above problems. Utility Model Content

[0006] In order to solve one or more of the above problems, the utility model provides a skull nail for assisting stereo positioning. The skull nail comprises: an implant end, the implant end is provided with a thread and has a tip, which is used to drill into the skull in a self-tapping manner and be threadedly connected to the skull; a tool joint, the tool joint is configured to engage with a driving tool to receive a rotational driving force from the driving tool, wherein the tool joint is provided with a probe joint for receiving a robot probe, and the size of the probe joint is designed so that the probe and the probe joint will not be accidentally disengaged; and a connecting part, the connecting part connects the implant end with the tool joint or is formed integrally with it, so that the three are arranged along a straight line, thereby defining the axis of the skull nail.

[0007] Furthermore, the axial length of the implant end portion does not exceed 5.0 mm.

[0008] According to one embodiment of the utility model, the implant end is in the shape of a right cone, the center line of the right cone coincides with the axis of the skull nail, and the cone angle of the right cone is 20° to 30°.

[0009] According to another embodiment of the present invention, the implant end portion comprises a cylindrical portion, the thread is arranged on the cylindrical portion, and the tip is arranged on a side of the cylindrical portion opposite to the connecting portion.

[0010] Furthermore, the tip is a flat pointed tip or a triangular tip; or the tip is also provided with a thread, and the tip is in the shape of a right circular cone and is provided with a cutting groove and a back angle, and the cone angle of the right circular cone is 30° to 45°.

[0011] According to yet another embodiment of the present invention, the connecting portion is cylindrical, and the axial length of the connecting portion along the axis of the skull nail can be selected according to actual needs.

[0012] Furthermore, a stopper is provided between the implantation end and the connecting portion.

[0013] Furthermore, the stop portion is in the form of a shoulder, the radial dimension of the shoulder is equal to the radial dimension of the connecting portion, but larger than the maximum radial dimension of the implant end; or the stop portion is in the form of a flange, the radial dimension of the flange is larger than the radial dimension of the connecting portion, and larger than the maximum radial dimension of the implant end; or the stop portion is in the form of a boss, the radial dimension of the boss is smaller than the radial dimension of the connecting portion, but larger than the maximum radial dimension of the implant end; or the stop portion is in the shape of a truncated cone, the minimum radial dimension of the truncated cone is equal to the maximum radial dimension of the implant end, and the maximum radial dimension of the truncated cone is equal to the radial dimension of the connecting portion.

[0014] According to another embodiment of the utility model, the probe coupling portion is arranged on a side of the tool coupling portion away from the implant end and is recessed along the axis toward the implant end, wherein the probe coupling portion is in the form of a conical groove, the cone angle of which is an obtuse angle; or the probe coupling portion is in the form of a cylindrical groove, the radial dimension of which is equal to or greater than the diameter of the probe, and the axial depth of the cylindrical groove is not less than the radius of the probe.

[0015] Furthermore, the skull nail is a medical device made of weakly magnetic titanium alloy material.

[0016] By using the skull nail for stereo positioning of the utility model, the purpose of easy implantation and small incision can be achieved, and the need for patients to undergo nuclear magnetic resonance examination before surgery can be met. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1A and Figure 1B They are respectively a front view and a right side view of a skull nail according to an embodiment of the utility model.

[0018] Figure 1C yes Figure 1A A partial cross-sectional view of a skull pin is shown illustrating a probe engagement portion for receiving a robotic probe.

[0019] Figure 2 A schematic diagram showing the use of a robot probe in cooperation with a skull pin according to the present invention positioned on a skull is shown.

[0020] Figure 3-Figure 5 They are shown respectively Figure 1A The alternative structures of the skull pins shown show several alternative structures of the stopper.

[0021] Fig. 6A and Figure 6B They are respectively a partial front view and a corresponding partial top view of a skull nail according to another embodiment of the utility model.

[0022] Figure 7A-7C They are respectively a partial front view and a corresponding rear view and a left side view of a skull nail according to yet another embodiment of the utility model.

[0023] Fig. 8A and Figure 8B They are respectively a partial front view and a left side view of a skull nail according to another embodiment of the utility model. DETAILED DESCRIPTION

[0024] The skull nail of the utility model will be described in more detail below with reference to the accompanying drawings. In the accompanying drawings, similar reference numerals are used to represent similar components, and the components in the accompanying drawings are not necessarily drawn to scale.

[0025] Hereinafter, the term "axial length" means the length along the axis, the term "cross section" is a cross section taken perpendicular to the axis, and the term "radial dimension" means a dimension obtained in the cross section.

[0026] Figure 1A-Figure 1C They are respectively a front view, a right side view and a partial cross-sectional view of a skull nail according to the first embodiment of the utility model.

[0027] Figure 1A-Figure 1C The skull pin 100 shown in the figure mainly includes an implant end 101, a connecting portion 102 and a tool engaging portion 103, and defines an axis XX of the skull pin 100. Although the implant end 101, the connecting portion 102 and the tool engaging portion 103 are shown as being integrally formed in the present invention, those skilled in the art can understand that these three parts can be formed separately and then connected together in sequence in a detachable manner (such as threaded connection, etc.) or a permanent connection manner (such as welding, etc.).

[0028] As shown in the figure, in this embodiment, the implant end 101 is in the shape of a right cone, and the center line of the right cone coincides with the axis XX of the skull nail 100. In order to avoid unnecessary damage to the skull when the skull nail 100 is used, the axial length L1 of the implant end 101 of the skull nail 100 is set to be less than 5 mm. The implant end 101 has a tip 1011 configured to be implanted into the skull and an opposite side 1012 opposite to the tip 1011, and the implant end 101 has a radial maximum dimension on the opposite side 1012. In order to facilitate the implantation of the skull nail 100 into the skull, the periphery of the implant end 101 is provided with threads from the tip 1011 to the opposite side 1012. Considering the rotational force applied to the skull nail 100 and the strength of the skull nail 100, the cone angle α of the implant end 101 can be 23° to 25°, preferably 24.12°, and its maximum radial dimension D1 is 2.3 mm to 2.6 mm, preferably 2.46 mm. The tip 1011 of the skull nail 100 adopts a thread structure with a small taper to realize self-drilling and self-tapping of the screw, which is convenient for implanting the skull nail 100 into the skull SK (shown in FIG. Figure 2 ). This structure can reduce the implantation torque and thus reduce the trauma caused on the patient's skull.

[0029] The tool engagement portion 103 is located at the end of the skull pin 100 opposite to the implantation end 101. The cross section of the tool engagement portion 103 is roughly square (eg Figure 1B) or hexagonal, etc., and is configured to engage with a tool (e.g., a torque tool) to receive a drilling torque from the tool. The structure of the tool engagement portion 103 can be customized to engage with a special tool, or can have a standard size to engage with a general tool. In order to facilitate engagement with the tool, the axial length L3 of the tool engagement portion 103 is not less than 5 mm. The tool engagement portion 103 includes a cylindrical portion 1031 and a truncated cone portion 1032 that are connected to each other or integrally formed. The cylindrical portion 1031 is configured to be connected to the connecting portion 102. The truncated cone portion 1032 is located at the end of the skull nail 100 and has a length L32 of not less than 3 mm (indicated in Figure 1A ). The cone angle of the truncated cone portion 1032 is 5° to 10°, preferably 7°. Taking a square cross section as an example, the side length of the cylindrical portion 1031 can be, for example, 4.2 mm. Those skilled in the art can imagine that in some alternative embodiments, the cylindrical portion 1031 can be omitted.

[0030] A probe engagement portion 1033 (shown in FIG. 1 ) is provided on the side of the truncated cone portion 1032 opposite to the implant end portion 101. Figure 1B and Figure 1C The probe joint 1033 is used to receive the probe of the robot (see Figure 2 ), and its size is designed to prevent the probe from accidentally disengaging from the probe joint 1033. In one embodiment, the probe joint 1033 is in the form of a tapered groove, see Figure 1B and Figure 1C . The taper and depth of the tapered groove can be selected according to the size of the probe to ensure stable contact between the two. For example, the taper angle β of the tapered groove can be 100° to 120°, preferably 118°, its maximum radial dimension w is equal to or greater than the diameter of the robot's spherical probe, and its depth d is 0.5mm to 1mm, preferably 0.75mm. Although the tapered groove is depicted as a conical groove in the figure, those skilled in the art will understand that the utility model is not limited to this, and it can also be a square tapered groove.

[0031] As an alternative embodiment, the probe joint can also be in the form of a cylindrical groove, the diameter of which can be equal to or slightly larger than the diameter of the (spherical) probe, and the axial depth of which is designed to be no less than the radius of the probe. As in the case of the aforementioned tapered groove, the cylindrical groove can be a cylindrical groove or a square cylindrical groove.

[0032] The connecting portion 102 is disposed between the implant end portion 101 and the tool engaging portion 103. The connecting portion 102 is cylindrical, and its cross section may be circular or other polygonal shapes. Taking the cylindrical shape as an example, the diameter of the connecting portion 102 may be equal to or slightly larger than the side length of the cylindrical portion 1031 (for example, a square cross section) of the tool engaging portion 103. According to actual needs, the axial length of the connecting portion 102 can be selected. The axial length L2 of the connecting portion 102 may be from 1.62 mm to 10.62 mm. Therefore, the axial length A (indicated at) from the side of the connecting portion 102 close to the implant end portion 101 to the side of the tool engaging portion 103 farthest from the implant end portion 101. Figure 1C The length A can be selected according to actual needs. The applicant provides four specifications for the length A, for example, 8 mm, 11 mm, 14 mm and 17 mm, according to actual needs. Of course, those skilled in the art can imagine that other specifications that meet the requirements can be selected according to actual conditions.

[0033] like Figure 1A and Figure 1C As shown in the figure, due to the size difference between the position where the opposite side 1012 of the implant end 101 is connected to the connecting portion 102, a shoulder 1021 is presented at the connecting position of the two. The existence of the shoulder 1021 acts as a stopper, which is intended to prevent the implant end 101 from drilling too deep into the skull, thereby causing damage to the skull.

[0034] A groove 104 is provided between the connecting portion 102 and the tool engaging portion 103, which is intended to facilitate machining of the skull pin 100. The axial length of the groove 104 is 1.0 mm to 1.5 mm, preferably 1.38 mm. When the cross section of the groove 104 is circular (the present invention is not limited thereto), its diameter is about 4.0 mm.

[0035] Figure 2 A schematic diagram of the robot probe cooperating with the skull pin according to the present invention positioned on the skull is shown. In the figure, the implant end 101 of the skull pin 100 has been screwed into the designated position of the skull SK by engaging the tool engagement portion 103 of the skull pin 100 with the torque tool, and the skull pin 100 is fixed to the skull by the threaded connection between the implant end 101 and the skull SK, and then the robot probe P is placed in the probe engagement portion 103 of the skull pin 100 to achieve the state shown in the figure. In this state, the robot locates the position shown by the skull pin 100 through the specific position of the probe P, thereby aligning the designated position of the patient's skull SK (for example, the patient's coordinates in the real world) to the robot's data system for use in surgery.

[0036] Figure 3 Shows Figure 1A-Figure 1C An alternative embodiment of the skull pin shown, the skull pin 100-1 is Figure 1A-Figure 1C The difference of the skull nail shown is that a stopper in the form of a flange 105-1 is provided between the implant end 101 and the connection part 102. The radial dimension of the flange 105 is larger than the maximum radial dimension of the implant end 101 and larger than the radial dimension of the connection part 102.

[0037] Figure 4 Shows Figure 1A-Figure 1C Another alternative embodiment of the skull pin shown, the skull pin 100-2 and Figure 1A-Figure 1C The difference of the skull nail shown is that a stopper in the form of a boss 105-2 is provided between the implant end 101 and the connection part 102. The radial dimension of the boss 105-2 is larger than the maximum radial dimension of the implant end 101, but smaller than the radial dimension of the connection part 102.

[0038] Figure 5 Shows Figure 1A-Figure 1C Another alternative embodiment of the skull pin shown. This embodiment can be regarded as a preferred embodiment of the skull pin. The skull pin 100-3 and Figure 1A-Figure 1C The difference of the skull nail shown is that a stopper in the form of a truncated cone 105-3 is provided between the implant end 101 and the connection portion 102. The minimum radial dimension of the truncated cone 105-3 is equal to the maximum radial dimension of the implant end 101, and the maximum radial dimension of the truncated cone 105-3 is equal to the radial dimension of the connection portion 102. The axial length L4 of the truncated cone 105-3 is about 2 mm, and its cone angle γ is greater than the cone angle α of the implant end 101, and can be 60° to 65°, preferably 63.8°.

[0039] As those skilled in the art can imagine, a suitable stopper in a variety of different forms can be provided between the implant end and the connecting portion, and the present invention is not limited to the disclosed forms.

[0040] Fig. 6A and Figure 6B A partial top view and a corresponding front view of another embodiment of a skull nail according to the utility model are shown. Fig. 6A and Figure 6B The skull pin 200 shown is Figure 5 The difference between the skull pin 100-3 shown is that the structure of the implant end is different. Fig. 6A and Figure 6B The implantation end 201 of the skull nail 200 shown in the figure includes a cylindrical portion 2011 configured to be connected to the connecting portion 102 and a flat tip 2012 connected to the cylindrical portion 2011. The outer circumference of the cylindrical portion 2011 is provided with a thread. Figure 5 Compared with the skull nail 100-3 shown, the skull nail 200 changes the conical thread into a cylindrical thread to increase the strength and stability of the screw, and sets the tip to a flat tip. This improvement on the tip can use the flat tip 2012 to pre-drill a hole in the skull before the thread is drilled into the skull, thereby making it easier to drill the subsequent cylindrical part 2011 with the thread.

[0041] Figure 7A-7C A partial front view and corresponding rear view and left side view of yet another embodiment of a skull pin according to the present utility model are shown. Figure 7A-7C The skull pin 300 shown in FIG. Figure 5 The difference between the skull pin 100-3 shown is also that the structure of the implant end is different. Figure 7A-7B The implant end portion 301 shown in the figure includes a cylindrical portion 3011 configured to be connected to the connecting portion 102 and a triangular head 3012 connected to the cylindrical portion 3011. The outer circumference of the cylindrical portion 3011 is provided with a thread. Figure 6A-6B Compared with the skull nail 200 shown, the skull nail 300 has a triangular tip, which enhances its drilling performance and further improves the screw strength at the front end of the thread.

[0042] Fig. 8A and Figure 8B A partial front view and a corresponding left side view of another embodiment of a skull pin according to the present utility model are shown. Fig. 8A and Figure 8B The skull pin 400 shown is Figure 5 The difference between the skull pin 100-3 shown is also that the structure of the implant end is different. Fig. 8A and Figure 8B The implant end 401 shown in the figure includes a cylindrical portion 4011 configured to be connected to the connecting portion 102 and a triangular head 4012 connected to the cylindrical portion 4011. The outer circumference of the cylindrical portion 4011 is provided with a thread. Figure 6A-6B Compared with the skull nail 200 shown in the figure, the skull nail 400 has a tip that is a conical portion with a threaded outer circumference, and further has a cutting angle and a back angle on the conical portion to enhance the drilling performance. Due to the presence of the cylindrical portion 4011, the cone angle of the conical portion is greater than Figure 5 The taper angle of the implant end 100 - 3 shown in FIG. 4 increases the stability of the skull pin 400 .

[0043] In addition, in order to enable the patient to undergo MRI examination after the skull pin is implanted, the material of the skull pin can be selected from materials such as weakly magnetic titanium alloy materials to reduce or even avoid any undesirable interference with the MRI examination results.

[0044] Although multiple embodiments of the utility model have been described with reference to the accompanying drawings, as will be appreciated by those skilled in the art, various modifications may be made to the above embodiments without departing from the scope defined by the appended claims. The above embodiments are provided only as examples to illustrate the technical solutions of the utility model and are not intended to limit the scope of protection of the utility model. Features or elements described in one embodiment may be incorporated into another embodiment for implementation unless they conflict with existing features or elements in another embodiment.

Claims

1. A skull nail for stereotaxic positioning, characterized in that: The skull nail comprises: An implant end portion, the implant end portion being provided with threads and having a tip, for drilling into the skull in a self-drilling manner and being threadedly connected to the skull; a tool engagement portion configured to engage with a driving tool to receive a rotational driving force from the driving tool, wherein the tool engagement portion is provided with a probe engagement portion for receiving a probe of a robot, the size of the probe engagement portion being designed so that the probe and the probe engagement portion will not accidentally disengage; and A connecting portion connects the implant end portion and the tool engaging portion or is formed integrally therewith, so that the three are arranged along a straight line, thereby defining the axis of the skull nail.

2. The skull nail according to claim 1, characterized in that: The axial length of the implant end does not exceed 5.0 mm.

3. The skull nail according to claim 2, characterized in that: The implantation end is in the shape of a right cone, the center line of the right cone coincides with the axis of the skull nail, and the cone angle of the right cone is 20° to 30°.

4. The skull nail according to claim 2, characterized in that: The implant end portion includes a cylindrical portion, the thread is disposed on the cylindrical portion, and the tip is disposed on a side of the cylindrical portion opposite to the connecting portion.

5. The skull nail according to claim 4, characterized in that: The tip is a flat tip or a triangular tip; or The tip is also provided with threads, and the tip is in the shape of a right circular cone and is provided with a cutting groove and a back angle, and the cone angle of the right circular cone is 30° to 45°.

6. The skull nail according to claim 1, characterized in that: The connecting portion is cylindrical, and the axial length of the connecting portion along the axis of the skull pin can be selected according to actual needs.

7. The skull nail according to claim 6, characterized in that: A stopper is provided between the implantation end and the connection portion.

8. The skull nail according to claim 7, characterized in that: The stop portion is in the form of a shoulder, the radial dimension of the shoulder is equal to the radial dimension of the connecting portion but greater than the maximum radial dimension of the implant end portion; or The stopper is in the form of a flange, the radial dimension of the flange is larger than the radial dimension of the connecting portion and larger than the maximum radial dimension of the implant end; or The stopper is in the form of a boss, the radial dimension of which is smaller than the radial dimension of the connecting portion but larger than the maximum radial dimension of the implant end; or The stopper portion is in a truncated cone shape, the minimum radial dimension of the truncated cone is equal to the maximum radial dimension of the implantation end, and the maximum radial dimension of the truncated cone is equal to the radial dimension of the connecting portion.

9. The skull nail according to claim 1, characterized in that: The probe engagement portion is disposed on a side of the tool engagement portion away from the implantation end portion and is recessed toward the implantation end portion along the axis. Wherein, the probe joint portion is in the form of a tapered groove, and the tapered angle of the tapered groove is an obtuse angle; or The probe engaging portion is in the form of a cylindrical groove, the radial dimension of the cylindrical groove is equal to or greater than the diameter of the probe, and the axial depth of the cylindrical groove is not less than the radius of the probe.

10. The skull nail according to claim 1, characterized in that: The skull nail is a medical device made of weakly magnetic titanium alloy material.

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