WO2022068118A1 - Cranial screw - Google Patents

Cranial screw Download PDF

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Publication number
WO2022068118A1
WO2022068118A1 PCT/CN2020/141955 CN2020141955W WO2022068118A1 WO 2022068118 A1 WO2022068118 A1 WO 2022068118A1 CN 2020141955 W CN2020141955 W CN 2020141955W WO 2022068118 A1 WO2022068118 A1 WO 2022068118A1
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WO
WIPO (PCT)
Prior art keywords
screw
thread
tooth
diameter
tail end
Prior art date
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PCT/CN2020/141955
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French (fr)
Chinese (zh)
Inventor
全华林
王航
宋春辉
张伟健
张高龙
Original Assignee
北京品驰医疗设备有限公司
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Application filed by 北京品驰医疗设备有限公司 filed Critical 北京品驰医疗设备有限公司
Publication of WO2022068118A1 publication Critical patent/WO2022068118A1/en

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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00—Electrotherapy; Circuits therefor
    • A61N1/02—Details
    • A61N1/04—Electrodes
    • A61N1/05—Electrodes for implantation or insertion into the body, e.g. heart electrode
    • A61N1/0526—Head electrodes
    • A61N1/0529—Electrodes for brain stimulation
    • A61N1/0539—Anchoring of brain electrode systems, e.g. within burr hole
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N1/00—Electrotherapy; Circuits therefor
    • A61N1/02—Details
    • A61N1/04—Electrodes
    • A61N1/05—Electrodes for implantation or insertion into the body, e.g. heart electrode
    • A61N1/0526—Head electrodes
    • A61N1/0529—Electrodes for brain stimulation
    • A61N1/0534—Electrodes for deep brain stimulation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/10—Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working

Definitions

  • the present invention relates to the field of bone implants, in particular, to a skull screw, which is mainly used for the fixation of medical instruments, especially electrode fixation devices, on the skull.
  • DBS Deep Brain Stimulation
  • Skull screws are a type of bone screw.
  • Bone screws are generally divided into self-tapping screws and non-self-tapping screws.
  • the basic structure of the two kinds of screws includes a cylindrical body, the outer surface of the body is provided with a set of external threads, and the external threads cooperate with the threads cut into the bone.
  • the engagement between the external thread and the internal bone thread provides initial stabilization of the screw, and long-term stability of the screw is provided by new bone growth around the screw.
  • a non-self-tapping screw is a threaded hole in which the thread is screwed into the bone, and the screw itself does not participate in drilling and tapping.
  • Self-tapping screws include cutting threads and flutes, and their tails have more obvious cones than non-self-tapping screws.
  • the cutting thread of the self-tapping screw is similar to a metal tap, which can cut the bone tissue into the bone when drilling, and the chip groove is conducive to the scraping of the bone tissue and the export of debris, thereby reducing the frictional resistance when the screw is tapped.
  • Non-self-tapping screws require pre-drilling prior to installation, and although this greatly reduces torque during screw insertion, clinical trials have shown that this approach establishes insufficient bone/screw contact, while making the procedure compact and operative. Actions strive for simple DBS surgery, this method has limitations.
  • the skull screw adopts the form of self-tapping screw, so it has the common structural features of self-tapping screw, such as cutting thread, tail cone, chip flute and so on.
  • the existing skull screws have shortcomings, which is that the comprehensive performance of the screw strength and self-tapping ability is difficult to guarantee. Specifically: when the screw strength is sufficient, the self-tapping performance is often poor, the screw introduction resistance is large, and the doctor's clinical operation At the same time, it may cause discomfort to the patient due to the increased torque; when the self-tapping performance of the screw is good, the strength of the screw is not enough, the screw is prone to breakage, and the safety and reliability are insufficient; performance can not meet the requirements.
  • the purpose of the present invention is to provide a new type of easy-tapping high-strength skull screw by analyzing the influence of the main parameters of the skull screw on the structural strength and self-tapping performance of the screw, optimizing the combination of parameters, and effectively preventing the screw from being easily broken or required.
  • the high screw-in torque exacerbates the problem of patient discomfort.
  • the present invention provides a skull screw
  • Screw head including arc surface, cylindrical surface and conical surface
  • Screw bodies including straight cylinders and serrated asymmetrical threads on the straight cylinders;
  • Screw tails including vertebral bodies and tapered threads on vertebral bodies;
  • the pitch P of the screw body and the screw tail end is 0.60-0.75mm;
  • the gradual thread has a top diameter and a bottom diameter of uniform transition, and the tip angle ⁇ 2 of the cone-like body is 48°-65°.
  • the size of the bottom diameter d 2 is 1.2-1.3 mm.
  • the outer circular surface of the straight cylinder is the same as the bottom diameter parting surface of the zigzag asymmetric thread; the top diameter and the bottom diameter of the zigzag asymmetric thread on each turn are respectively the same.
  • both the zigzag asymmetric thread and the gradual thread have a specially designed tooth structure, the tooth structure has a narrow ridge-like platform at the top of the tooth, and the width e of the ridge-like platform is 0.05-0.15mm.
  • the chamfering radius r 5 of the top of the tooth is 0-0.05 mm; and/or, the tooth flank angle ⁇ of the side of the tooth structure close to the screw head is 3°-5° and/or, the tooth flank angle ⁇ of the tooth structure close to the tail end of the screw is 32°-38°
  • a tooth bottom chamfer on the side of the tooth structure close to the tail end of the screw, the radius r 3 of the tooth bottom chamfer is 0.25-0.3 mm; and/or, the tooth structure
  • the tooth bottom chamfer on the side close to the screw head is chamfered, and the radius r 4 of the tooth bottom chamfer is 0.05-0.1 mm.
  • the tail end of the screw includes a chip flute
  • the chip flute passes through multiple threads
  • the number of turns of the multiple threads is not less than 2
  • the cross-sectional angle ⁇ of the chip flute 3 is 75°-112° and includes a scraping edge with scraping action.
  • the center of the arc surface is provided with a cross-shaped drive slot used as a drive interface for screw connection, the cross-shaped drive slot extends orthogonally outward from the center of the arc surface, and the extension length is between the cylinders.
  • 60%-98% of the diameter d 3 of the face; and/or, the radius r 1 of the arc-shaped bottom of the cross-shaped drive groove is 90%-100% of the diameter d 3 of the cylindrical surface; and/or, the ten
  • the depth l of the font-shaped driving groove is 0.7-0.9 mm.
  • the threads of the screw body and the screw tail end are single-threaded right-hand threads.
  • the overall length of the screw is 5.8-6 mm; the diameter d 3 of the cylindrical surface of the screw head is 2.95-3 mm; the top diameter d 1 of the asymmetric thread of the screw body is 1.775-1.825 mm.
  • the technical effect of the present invention is that the parameter-optimized skull screw has the characteristics of easy tapping and high strength, and can be successfully tapped into the bone with a special torque screwdriver at a low torque, and achieves relatively low torque. Good surgical fixation.
  • Fig. 1 is the side view of the skull screw of the present invention
  • Figure 2 is an end view of the skull screw of the present invention
  • Figure 3 is a bottom view of a longitudinal section of the skull screw flute of the present invention.
  • Figure 4 is a cross-sectional view of the skull screw of the present invention.
  • FIG. 5 is a partial enlarged view of the thread profile of the skull screw of the present invention.
  • Figure 7 is an end view of the torque driver for the skull screw of the present invention.
  • the invention relates to a skull screw, which has the characteristics of easy tapping and high strength.
  • "Easy-tapping” should be understood as the self-tapping performance of the screw is good, the screw-in torque is small, and the insertion into the bone is easy. Tensile compression and torsional strength are in line with surgical requirements. It should be pointed out that there is a certain negative correlation between the self-tapping performance and structural strength of cranial screws. Only by comprehensively weighing the structural parameters of the screw can the two performances achieve a better balance. "Easy tapping and high strength” refers to the excellent comprehensive performance of the two, not just the outstanding performance of a certain performance.
  • the skull screw provided by the present invention can be designed through the optimized combination of the remaining structural parameters of the screw, and the comprehensive performance of its self-tapping performance and structural strength can be achieved. Better than ordinary skull screws.
  • Figure 1 is a side view of the skull screw of the present invention.
  • the screw of the present invention includes: screw head 1 , screw head arc surface 11 , arc cross-shaped driving groove 111 , screw head cylindrical surface 12 , screw head cone surface 13 , cone surface chamfer 131 , screw main body 2, screw main body polished rod 21, main body straight cylinder 22, main body zigzag asymmetric thread 23, large bottom chamfer of asymmetric thread body 231, asymmetric thread tooth bottom small chamfer 232 , The crest 233 of the asymmetric thread body, the screw tail end 3, the screw tail end tapered thread 31, the tapered thread cutting edge 311, the screw tail end chip groove 32, the chip groove scraping edge 321, and the tip angle of the screw tail end.
  • the main characteristic dimensions of the skull screw of the present invention are shown in FIG. 4 .
  • the overall length of the screw is 6mm
  • the upper tolerance is 0,
  • the lower tolerance is -0.2mm
  • the diameter d3 of the cylindrical surface 12 of the screw head is 3mm
  • the upper tolerance is 0,
  • the lower tolerance is -0.05mm
  • the screw body is asymmetrical thread
  • the top diameter d 1 of 23 is 1.8mm
  • the upper tolerance is +0.025mm
  • the lower tolerance is -0.025mm.
  • the aforementioned three dimensions are the basic dimensions of this embodiment, and the rest of the structural parameters of the screw are based on these parameters remain unchanged. Carry out optimal combination design.
  • the screw of the present invention is made of a group of medical-grade biocompatible materials capable of resisting high torque, including but not limited to titanium alloy, cobalt-chromium and high-strength resin polymer, and titanium alloy is preferred in terms of comprehensive performance and application maturity ,
  • the screws of this embodiment are made of titanium alloy material TC4 (GB/T13810).
  • the screw of the present invention does not impose strict restrictions on the thread and the direction of rotation of the thread, and can be selected according to actual application conditions.
  • the introduction efficiency of single thread thread can meet the requirements, and the double thread thread can theoretically increase the introduction efficiency, but in the actual introduction process, due to the increase of the contact surface between the thread and the bone tissue, the friction force Increase, but increase the difficulty of screw introduction.
  • right-hand threads are in line with the idiom that people "turn clockwise to tighten, and counterclockwise to loosen”. Therefore, the thread of the screw in this embodiment is a single-thread right-hand thread.
  • the included angle ⁇ 1 of the taper surface 13 of the screw head is at least 90° to prevent the screw from being easily pulled out axially. It is recommended that the included angle ⁇ 1 be between 90° and 120°. In this embodiment, ⁇ 1 is 100° .
  • the diameter of the arc of the arc surface 11 of the screw head is between 2 and 3 times the diameter d3 of the cylindrical surface of the screw head, and the diameter of the arc of the arc surface 11 of the screw head is between 6-9 mm.
  • this embodiment The arc diameter of the arc surface 11 of the screw head is 6.36 mm.
  • the cross-shaped driving groove 111 of the screw head extends orthogonally outward from the center of the arc surface 11, and the extension length is between 60%-98% of the diameter of the cylindrical surface of the screw head, and the optimal extension length is In order to ensure the maximum driving torque of the screw without destroying the integrity of the outer circle of the nail head and the structural strength.
  • the bottom of the cross-shaped drive slot 111 is arc-shaped to reduce the amount of material removed from the screw head 1 when machining the cross-shaped drive slot 111, and to maximize the strength of the screw head.
  • the outer circle radius r 1 should be between 90%-100% of the diameter of the cylindrical surface of the screw head, and the depth l of the cross-shaped driving slot 111 should be between 0.7-0.9 mm.
  • the extension length of the cross-shaped driving slot 111 in this embodiment is about 2.90 mm
  • the outer radius r1 of the arc bottom of the cross-shaped driving slot 111 is 2.75 mm
  • the depth l of the cross-shaped driving slot 111 is 0.75 mm.
  • the structure is capable of providing sufficient torque to allow the screw to be driven into the skull and sufficient strength to resist torsional deformation of the head of the screw and the torque driver for the screw during installation. If the extension length of the cross-shaped driving slot 111 is less than 60% of the diameter of the cylindrical surface of the screw head, it will cause the screwdriver to be difficult to fit and provide a small torque; It will lead to low strength of the screw head and easy deformation.
  • the outer radius r 1 of the cross-shaped drive slot 111 is less than 90% of the diameter of the cylindrical surface of the screw head, it will cause the cross-shaped drive slot to be difficult to fit with the tool and easy to slide the wire; if the outer radius r 1 of the cross-shaped drive slot 111 is larger than the screw The diameter of the cylindrical surface of the head will lead to the strength of the cross-shaped drive groove and it is easy to break. If the depth l of the cross-shaped driving slot 111 is less than 0.7mm, it will cause the cross-shaped driving slot to be difficult to fit the tool and easy to slide the wire; Fragile.
  • the rounded corner radius r 2 is between 0-0.3 mm. It should be pointed out that for screws whose head and the contact surface of the fixation device need to be in strict and flat contact, rounding is not recommended at the connection between the head and the main body.
  • the rounded corners are used to make the transition between the screw head 1 and the screw body 2 evenly, to avoid stress concentration, and to better transmit the driving torque of the screw head 1 to the screw body 2.
  • the rounded corners r 2 is 0.3mm.
  • the screw body 2 has a straight cylindrical body 22 and a serrated asymmetrical thread 23, and the straight cylindrical body is more conducive to the screw structure having better strength.
  • the outer circular surface of the straight cylinder 22 is the same as the bottom diameter parting surface of the thread 23 , and the top diameter and the bottom diameter of the threads 23 of each circle on the screw body 2 are respectively the same. Among them, under the condition that the top diameter d1 of the thread 23 remains unchanged at 1.8mm, the bottom diameter d2 of the thread 23 is 1.2mm to 1.3mm to obtain a better comprehensive performance between self-tapping performance and structural strength. 23 The bottom diameter d 2 is 1.20mm.
  • bottom diameter d 2 of the thread 23 is less than 1.2 mm, the strength of the screw is low and it is easy to break; if the bottom diameter d 2 of the thread 23 is greater than 1.3 mm, the feed rate of the screw is small and it is difficult to tap.
  • the thread profile of the screw body 2 is shown in Figure 5 .
  • the chamfering radii r 3 and r 4 at the bottom of the tooth mainly affect the strength of the thread
  • the flank angles ⁇ and ⁇ of the tooth mainly affect the cutting efficiency of the thread
  • the chamfering radius r 5 at the top of the tooth is related to the ridge-like platform.
  • the size of the width e affects the strength and cutting efficiency of the thread at the same time, and is affected by the hardness of the screw itself and the hardness of the bone tissue to be cut.
  • the width e of the shape platform should be smaller.
  • the preferred value range of the chamfering radius r 3 at the bottom of the tooth body close to the end of the screw is 0.25-0.3 mm, and it is close to the head of the screw.
  • the preferred value range of the chamfering radius r 4 at the bottom of the tooth on one side is 0.05-0.1 mm, and the preferred value range of the tooth flank angle ⁇ on the side close to the screw head is 3°-5°, close to the screw tail
  • the preferred value range of the tooth flank angle ⁇ on the end side is 32°-38°
  • the preferred value range of the chamfer radius r 5 of the tooth top is 0-0.05mm
  • the preferred ridge-like platform width e is The value range is 0.05-0.15mm.
  • the selected structural parameters of the tooth type are: the bottom chamfers r 3 and r 4 of the tooth are 0.3 mm and 0.1 mm respectively, the flank angles ⁇ and ⁇ of the tooth are 3° and 35° respectively,
  • the chamfer r5 at the top of the body and the width e of the ridge - like platform are 0.05mm and 0.1mm, respectively. If the chamfering radius r3 at the bottom of the tooth body is less than 0.25mm, the strength of the screw will be low, and the screw will be easily broken. If the chamfering radius r3 at the bottom of the tooth body is greater than 0.3mm, the resistance surface of the screw will be large and it will be difficult to tap. The problem.
  • the chamfer radius r 4 at the bottom of the tooth is less than 0.05mm, the strength of the screw will be low, and the screw will be easily broken; if the chamfer radius r 4 at the bottom of the tooth is greater than 0.1mm, the resistance surface of the screw will be large, The problem of not easy tapping. If the tooth flank angle ⁇ is less than 3°, the screw feed will be small and the tapping efficiency will be low; if the tooth flank angle ⁇ is greater than 5°, the screw feed will be too large. Due to the large feeding resistance, it is not easy to tap.
  • the tooth flank angle ⁇ is less than 32°, the screw feed will be small and the tapping efficiency will be low; if the tooth flank angle ⁇ is greater than 38°, the screw feed will be excessive. Large, the feeding resistance is large, and it is not easy to tap. If the width e of the ridge-like platform is less than 0.05mm, the strength of the screw is low and it is easy to break; if the width e of the ridge-like platform is greater than 0.15mm, the screw feed resistance is large and it is not easy to tap. If the chamfer r 5 at the top of the tooth is larger than 0.05mm, the width of the ridge-like platform will be too small and it will be easy to break.
  • the screw tail end 3 includes a cone-like body 33 and a gradient thread 31 on the cone-like body.
  • the structure of the cone-like body 33 and the gradient thread 31 is conducive to the introduction and tapping of the screw tail end 3.
  • the chip groove 32 on the gradient thread 31 has It is beneficial to export or accommodate bone tissue debris, so as to reduce the resistance of the screw to the bone tissue material, thereby reducing the screw-in torque.
  • the number of turns of the chip flute 32 passing through the thread depends on the structural strength of the screw. On the premise that the strength of the screw meets the requirements, the more the number of turns of the thread passing through, the more conducive to the export of chips. As shown in FIG.
  • the scraping edge 321 on the chip flute 32 also has the function of scraping the thread shape, and the scraping effect is affected by the size of the included angle ⁇ 3 of the chip flute section.
  • the included angle ⁇ 3 of the flute section is in the range of 45°-120°, and the smaller the angle, the better the scraping effect.
  • the size of the included angle ⁇ 3 of the chip flute section also affects the rate of chip ejection. In theory, within the range of 45°-120°, the larger the included angle, the faster the chip ejection efficiency. In general, the angle dimension ⁇ 3 of the chip flute section is between 75°-112° to obtain a better value.
  • the included angle dimension ⁇ 3 of the chip flute section of the screw in this embodiment is 90°. If the included angle dimension ⁇ 3 of the chip flute section is less than 75°, there will be problems such as less chip capacity or slow chip ejection, high screw feeding resistance, and difficulty in tapping; if the included angle dimension ⁇ 3 of the chip flute section is greater than 112° , there will be problems of low screw strength and easy breakage.
  • the gradient thread 31 of the screw has a uniform transition top diameter and bottom diameter. Taking into account the hardness of the bone and the material of the screw at the same time, its tip angle ⁇ 2 is between 48°-65° to obtain the screw drilling efficiency and screw tail. The optimal balance of end strength.
  • the tip angle ⁇ 2 of the tail end of the screw in this embodiment is 60°. If the angle of the tip angle is less than 48°, the strength of the tail end of the screw is low and it is easy to break; if the angle of the tip angle is greater than 65°, the tail end of the screw is difficult to feed and difficult to tap.
  • the screw body 2 and the screw tail 3 have the same pitch P.
  • the basis for the design optimization of the pitch P is as follows:
  • the thread pitch P is inversely proportional to the axial output force, that is, the smaller the thread pitch P, the greater the axial output force F, and the greater the feed force in the screw bone; when the axial output force F and
  • the pitch P is proportional to the driving torque M, that is, the smaller the pitch P, the smaller the required driving torque M, and the smaller the screw-in torque. Therefore, in order to output a large axial output force under a small driving torque, the pitch P of the screw should be as small as possible.
  • the feed amount W of the screw is equal to the pitch P of the screw, that is, when the driving rate is constant, the smaller the pitch P, the smaller the feed amount W of the screw, and the corresponding clinical operation is as follows: the doctor drives the small pitch screw The torque of the screw is small, but the tapping rate of the screw is correspondingly slow, and the doctor needs to rotate more turns to completely fix the screw.
  • the pitch P of the screw should obtain a certain intermediate value within a certain range, so that the driving torque of the screw is small and the screwing rate is fast.
  • the screw pitch P is preferably 0.60-0.75 mm, and the screw pitch P in the preferred example of this embodiment is 0.70 mm. If the pitch P is less than 0.60mm, the feed rate of the screw is small and the tapping efficiency is slow; if the pitch P is greater than 0.75mm, the screw feeding resistance is large and it is not easy to tap.
  • FIGS. 6 and 7 are respectively a partial side view and an end view of a torque screwdriver 4 matched with a skull screw according to an embodiment of the present invention.
  • the cross-shaped bit 41 of the torque screwdriver 4 is installed in conjunction with the cross-shaped groove driving slot 111 of the screw head.
  • the screw of the present invention can be easily manufactured by using a modern lathe capable of cutting threads, and can also be processed and formed at one time by CNC, and the surface of the screw is deburred, polished and anodized.
  • the screw torque test and fracture torsion angle are tested according to the method specified in YY/T0662, the maximum torque is ⁇ 0.5N m, and the maximum fracture torsion angle is ⁇ 150°.
  • the hardness of the screw material is measured according to the method specified in GB/T4340.1, and the material hardness is greater than or equal to 260HV.
  • the screw torque is tested according to YY/T1506-2016, and the average screw-in torque is 0.25N m.
  • the self-tapping performance and strength test of the screw of the invention and the traditional skull screw on the bovine bone can be completely and smoothly screwed into the bovine bone under a lower torque value, and the screw has no cracks.
  • the measured average complete screw-in torque value of the traditional skull screw is 0.282N.m
  • the measured average screw-in torque value of the preferred embodiment skull screw is 0.226N.m.
  • the preferred embodiment The self-tapping performance optimization rate of the skull screw is 19.8%; the measured average breaking torque of the traditional skull screw is 0.49N.m, and the measured average breaking torque of the skull screw of the preferred embodiment is 0.51N.m.
  • the structural strength of the skull screw of the preferred embodiment is 4%. Because the skull screw of the preferred embodiment has better self-tapping performance compared with the traditional skull screw, and the introduction resistance is small, the possibility of fracture during the actual tapping process is smaller, and its self-tapping performance and structural strength are better than the traditional skull screw. .

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Abstract

A cranial screw, which relates to the field of bone implants. The cranial screw comprises: a screw head (1) comprising a cambered face (11), a cylindrical face (12) and a conical face (13); a screw main body (2) comprising a straight cylinder (22) and a serrated asymmetric thread (23) on the straight cylinder (22); and a screw tail end (3) comprising a cone-like body (33) and a gradient thread (31) on the cone-like body (33), wherein the screw main body (2) and the screw tail end (3) have a screw pitch (P) of 0.60-0.75 mm; the gradient thread (31) has a top diameter and a bottom diameter which have uniform transition; and the cone-like body (33) has a tip angle (θ2) of 48°-65°. The cranial screw, which has been subjected to parameter optimization, has the characteristics of easy tapping and high strength, can be smoothly tapped into bone under low torque by means of a special torque screwdriver (4), and achieves a good surgical fixation effect.

Description

一种颅骨螺钉a skull screw 技术领域technical field
本发明涉及骨植入物领域，具体而言，涉及一种颅骨螺钉，主要用于医疗器械尤其是电极固定装置在颅骨上的固定。The present invention relates to the field of bone implants, in particular, to a skull screw, which is mainly used for the fixation of medical instruments, especially electrode fixation devices, on the skull.
背景技术Background technique
在脑深部刺激术(Deep Brain Stimulation，DBS)手术中，经常需要用紧固件将植入器械固定在颅骨上，这种紧固件常见的有颅骨螺钉。In Deep Brain Stimulation (DBS) surgery, it is often necessary to fix the implanted device on the skull with fasteners, such as skull screws.
颅骨螺钉属于骨螺钉的一种。骨螺钉一般分为自攻螺钉和非自攻螺钉。所述两种螺钉的基本结构都包括一个圆柱形的主体，该主体外表面有一组外螺纹，外螺纹与切入骨头的螺纹配合连接。对于所述两种螺钉，外螺纹与骨内螺纹之间的配合提供了螺钉的初始稳定，螺钉长期的稳定性是由螺钉周围的新骨生长所提供的。Skull screws are a type of bone screw. Bone screws are generally divided into self-tapping screws and non-self-tapping screws. The basic structure of the two kinds of screws includes a cylindrical body, the outer surface of the body is provided with a set of external threads, and the external threads cooperate with the threads cut into the bone. For both types of screws, the engagement between the external thread and the internal bone thread provides initial stabilization of the screw, and long-term stability of the screw is provided by new bone growth around the screw.
非自攻螺钉是将螺纹旋入到骨内的螺纹孔，螺钉本身不参与钻孔与攻丝。自攻螺钉则包括切削螺纹和出屑槽，其尾端相对非自攻螺钉有更明显的椎体。自攻螺钉的切削螺纹类似于金属丝锥，可在钻孔时切削骨组织进入骨头，出屑槽则有利于骨组织的刮削及碎屑的导出，进而减少螺钉攻丝时受到的摩擦阻力。A non-self-tapping screw is a threaded hole in which the thread is screwed into the bone, and the screw itself does not participate in drilling and tapping. Self-tapping screws include cutting threads and flutes, and their tails have more obvious cones than non-self-tapping screws. The cutting thread of the self-tapping screw is similar to a metal tap, which can cut the bone tissue into the bone when drilling, and the chip groove is conducive to the scraping of the bone tissue and the export of debris, thereby reducing the frictional resistance when the screw is tapped.
非自攻螺钉在安装前需预先钻孔，尽管这大大降低了螺钉旋入过程中的扭矩，但临床试验表明，这种方法建立了不充分的骨/螺钉接触，同时对于操作程序紧凑、操作动作力求简单的DBS手术，此方法有所限制。Non-self-tapping screws require pre-drilling prior to installation, and although this greatly reduces torque during screw insertion, clinical trials have shown that this approach establishes insufficient bone/screw contact, while making the procedure compact and operative. Actions strive for simple DBS surgery, this method has limitations.
有鉴于此，颅骨螺钉采用自攻螺钉的形式，因而具有自攻螺钉常见的切削螺纹、尾端椎体、出屑槽等结构特征。In view of this, the skull screw adopts the form of self-tapping screw, so it has the common structural features of self-tapping screw, such as cutting thread, tail cone, chip flute and so on.
然而现有的颅骨螺钉存在不足之处，其表现为螺钉强度和自攻能力的综合性能难以保证，具体地：当螺钉强度足够时，自攻性能往往欠佳，螺钉导入阻力大，医生临床操作时的手感差，同时因扭矩增大可能造成患者的不适；当螺钉自攻性能较好时，螺钉的强度不够，螺钉容易发生断裂，安全可靠性不足；有的则表现为螺钉强度与自攻性能均不能满足要求。However, the existing skull screws have shortcomings, which is that the comprehensive performance of the screw strength and self-tapping ability is difficult to guarantee. Specifically: when the screw strength is sufficient, the self-tapping performance is often poor, the screw introduction resistance is large, and the doctor's clinical operation At the same time, it may cause discomfort to the patient due to the increased torque; when the self-tapping performance of the screw is good, the strength of the screw is not enough, the screw is prone to breakage, and the safety and reliability are insufficient; performance can not meet the requirements.
发明内容SUMMARY OF THE INVENTION
本发明的目的为：通过分析颅骨螺钉各主要参数对螺钉结构强度与自攻性能的影响，优化组合各参数，提供一种新型的易攻丝高强度颅骨螺钉，有效避免螺钉容易断裂或所需旋入扭矩大而加剧病人不适的问题。The purpose of the present invention is to provide a new type of easy-tapping high-strength skull screw by analyzing the influence of the main parameters of the skull screw on the structural strength and self-tapping performance of the screw, optimizing the combination of parameters, and effectively preventing the screw from being easily broken or required. The high screw-in torque exacerbates the problem of patient discomfort.
为实现上述目的，本发明提供一种颅骨螺钉，In order to achieve the above object, the present invention provides a skull screw,
螺钉头部，包括弧面、圆柱面与锥面；Screw head, including arc surface, cylindrical surface and conical surface;
螺钉主体，包括直形柱体和直形柱体上的锯齿状不对称螺纹；Screw bodies, including straight cylinders and serrated asymmetrical threads on the straight cylinders;
螺钉尾端，包括类椎体和类椎体上的渐变螺纹；Screw tails, including vertebral bodies and tapered threads on vertebral bodies;
所述螺钉主体和所述螺钉尾端的螺距P为0.60-0.75mm；The pitch P of the screw body and the screw tail end is 0.60-0.75mm;
所述渐变螺纹具有均匀过渡的顶径与底径，所述类椎体的顶尖角θ 2为48°-65°。 The gradual thread has a top diameter and a bottom diameter of uniform transition, and the tip angle θ 2 of the cone-like body is 48°-65°.
可选的，所述底径d 2的尺寸为1.2-1.3mm。 Optionally, the size of the bottom diameter d 2 is 1.2-1.3 mm.
可选的，所述直形柱体的外圆面与所述锯齿状不对称螺纹的底径分型面相同；所述锯齿状不对称螺纹在各圈上的顶径与底径分别相同。Optionally, the outer circular surface of the straight cylinder is the same as the bottom diameter parting surface of the zigzag asymmetric thread; the top diameter and the bottom diameter of the zigzag asymmetric thread on each turn are respectively the same.
可选的，所述锯齿状不对称螺纹与所述渐变螺纹均具有特制的牙体结构，所述牙体结构牙体顶部具有较窄的类脊状平台，所述类脊状平台宽度e为0.05-0.15mm。Optionally, both the zigzag asymmetric thread and the gradual thread have a specially designed tooth structure, the tooth structure has a narrow ridge-like platform at the top of the tooth, and the width e of the ridge-like platform is 0.05-0.15mm.
可选的，所述牙体顶部倒角半径r 5为0-0.05mm；和/或，所述牙体结构靠近所述螺钉头部一侧的牙体牙侧角α为3°-5°；和/或，所述牙体结构靠近所述螺钉尾端一侧的牙体牙侧角β为32°-38° Optionally, the chamfering radius r 5 of the top of the tooth is 0-0.05 mm; and/or, the tooth flank angle α of the side of the tooth structure close to the screw head is 3°-5° and/or, the tooth flank angle β of the tooth structure close to the tail end of the screw is 32°-38°
可选的，所述牙体结构靠近所述螺钉尾端一侧的牙体底部倒角，所述牙体底部倒角的半径r 3为0.25-0.3mm；和/或，所述牙体结构靠近所述螺钉头部一侧的牙体底部倒角，所述牙体底部倒角的半径r 4为0.05-0.1mm。 Optionally, a tooth bottom chamfer on the side of the tooth structure close to the tail end of the screw, the radius r 3 of the tooth bottom chamfer is 0.25-0.3 mm; and/or, the tooth structure The tooth bottom chamfer on the side close to the screw head is chamfered, and the radius r 4 of the tooth bottom chamfer is 0.05-0.1 mm.
可选的，所述螺钉尾端包括一个出屑槽，所述出屑槽穿过多圈螺纹，所述多圈螺纹的圈数不少于2圈，所述出屑槽的截面夹角θ 3为75°-112°，且包括具有刮削作用的刮削刃。 Optionally, the tail end of the screw includes a chip flute, the chip flute passes through multiple threads, the number of turns of the multiple threads is not less than 2, and the cross-sectional angle θ of the chip flute 3 is 75°-112° and includes a scraping edge with scraping action.
可选的，所述弧面的中心处设置有用于螺钉连接时作为驱动接口的十字形驱动槽，所述十字形驱动槽从弧面中心处正交向外延伸，延伸长度介于所述圆柱面直径d 3的60％-98％；和/或，所述十字形驱动槽弧形底部的半径r 1为所述圆柱面直径d 3的90％-100％；和/或，所述十字形驱动槽的深度l为0.7-0.9mm。 Optionally, the center of the arc surface is provided with a cross-shaped drive slot used as a drive interface for screw connection, the cross-shaped drive slot extends orthogonally outward from the center of the arc surface, and the extension length is between the cylinders. 60%-98% of the diameter d 3 of the face; and/or, the radius r 1 of the arc-shaped bottom of the cross-shaped drive groove is 90%-100% of the diameter d 3 of the cylindrical surface; and/or, the ten The depth l of the font-shaped driving groove is 0.7-0.9 mm.
可选的，所述螺钉主体和所述螺钉尾端的螺纹为单线程右旋螺纹。Optionally, the threads of the screw body and the screw tail end are single-threaded right-hand threads.
可选的，所述螺钉整体长度为5.8-6mm；所述螺钉头部圆柱面的直径d 3为2.95-3mm；所述螺钉主体不对称螺纹的顶径d 1为1.775-1.825mm。 Optionally, the overall length of the screw is 5.8-6 mm; the diameter d 3 of the cylindrical surface of the screw head is 2.95-3 mm; the top diameter d 1 of the asymmetric thread of the screw body is 1.775-1.825 mm.
相对于现有技术，本发明的技术效果是：经过参数优化的颅骨螺钉具备易攻丝高强度的特性，可配合专用的力矩螺丝刀在较低的扭矩下顺利地攻入骨头中，并实现较好的手术固定效果。Compared with the prior art, the technical effect of the present invention is that the parameter-optimized skull screw has the characteristics of easy tapping and high strength, and can be successfully tapped into the bone with a special torque screwdriver at a low torque, and achieves relatively low torque. Good surgical fixation.
附图说明Description of drawings
为了更清楚地说明本发明实施例或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本发明的实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据提供的附图获得其他的附图。In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to the provided drawings without creative work.
图1是本发明的颅骨螺钉的侧视图；Fig. 1 is the side view of the skull screw of the present invention;
图2是本发明的颅骨螺钉的端部视图；Figure 2 is an end view of the skull screw of the present invention;
图3是本发明的颅骨螺钉出屑槽的一个纵向剖面的底部视图；Figure 3 is a bottom view of a longitudinal section of the skull screw flute of the present invention;
图4是本发明的颅骨螺钉的横切剖视图；Figure 4 is a cross-sectional view of the skull screw of the present invention;
图5是本发明的颅骨螺钉的螺纹牙型局部放大图；5 is a partial enlarged view of the thread profile of the skull screw of the present invention;
图6及本发明的颅骨螺钉相配套的力矩螺丝刀的局部侧视图；Fig. 6 and the partial side view of the torque screwdriver matched with the skull screw of the present invention;
图7是本发明的颅骨螺钉相配套的力矩螺丝刀的端部视图。Figure 7 is an end view of the torque driver for the skull screw of the present invention.
具体实施方式Detailed ways
下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.
本发明涉及一种颅骨螺钉，具备易攻丝高强度的特性。“易攻丝”应理解为螺钉的自攻性能较好，螺钉旋入扭矩小，骨内易导入，“高强度”应理解为螺钉完全导入时具备足够的结构强度，导入过程不易发生断裂，拉压及抗扭强度均符合手术要求。应当指出的是，颅骨螺钉的自攻性能与结构强度之间存在一定的负相关关系，螺钉的结构参数只有通过综合权衡，才可使得两种性能取到较优的平衡状态。而“易攻丝高强度”指的正是两者综合性能的优异，而不单指某一性能的显著 突出。The invention relates to a skull screw, which has the characteristics of easy tapping and high strength. "Easy-tapping" should be understood as the self-tapping performance of the screw is good, the screw-in torque is small, and the insertion into the bone is easy. Tensile compression and torsional strength are in line with surgical requirements. It should be pointed out that there is a certain negative correlation between the self-tapping performance and structural strength of cranial screws. Only by comprehensively weighing the structural parameters of the screw can the two performances achieve a better balance. "Easy tapping and high strength" refers to the excellent comprehensive performance of the two, not just the outstanding performance of a certain performance.
本发明提供的颅骨螺钉在螺钉整体长度、螺钉头部外圆直径及螺钉螺纹顶径尺寸不变的情况下，通过对螺钉其余结构参数的优化组合设计，其自攻性能与结构强度的综合性能优于普通的颅骨螺钉。Under the condition that the overall length of the screw, the outer diameter of the screw head and the top diameter of the screw thread are unchanged, the skull screw provided by the present invention can be designed through the optimized combination of the remaining structural parameters of the screw, and the comprehensive performance of its self-tapping performance and structural strength can be achieved. Better than ordinary skull screws.
为了使本技术领域的技术人员更好地理解本发明方案，下面结合附图和具体实施方式对本发明进一步的详细说明。In order to make those skilled in the art better understand the solution of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.
图1是本发明的颅骨螺钉的侧视图。如图1所示，本发明的螺钉包括：螺钉头部1、螺钉头部弧面11、弧面十字形驱动槽111、螺钉头部圆柱面12、螺钉头部锥面13、锥面倒角131、螺钉主体2、螺钉主体光杆21、主体直形柱体22、主体锯齿状不对称螺纹23、不对称螺纹牙体的牙底大倒角231、不对称螺纹牙体的牙底小倒角232、不对称螺纹牙体的牙顶233、螺钉尾端3、螺钉尾端渐变螺纹31、渐变螺纹切削刃311、螺钉尾端出屑槽32、出屑槽刮削刃321、螺钉尾端的顶尖角。Figure 1 is a side view of the skull screw of the present invention. As shown in FIG. 1 , the screw of the present invention includes: screw head 1 , screw head arc surface 11 , arc cross-shaped driving groove 111 , screw head cylindrical surface 12 , screw head cone surface 13 , cone surface chamfer 131 , screw main body 2, screw main body polished rod 21, main body straight cylinder 22, main body zigzag asymmetric thread 23, large bottom chamfer of asymmetric thread body 231, asymmetric thread tooth bottom small chamfer 232 , The crest 233 of the asymmetric thread body, the screw tail end 3, the screw tail end tapered thread 31, the tapered thread cutting edge 311, the screw tail end chip groove 32, the chip groove scraping edge 321, and the tip angle of the screw tail end.
本发明的颅骨螺钉的各主要特征尺寸如图4所示。其中，螺钉整体长度为6mm，上公差为0，下公差为-0.2mm，螺钉头部圆柱面12的直径d 3为3mm，上公差为0，下公差为-0.05mm，螺钉主体不对称螺纹23的顶径d 1为1.8mm，上公差为+0.025mm，下公差为-0.025mm，前述三个尺寸为本实施例的基本尺寸，螺钉其余结构参数皆基于这些参数保持不变的情况下进行优化组合设计。 The main characteristic dimensions of the skull screw of the present invention are shown in FIG. 4 . Among them, the overall length of the screw is 6mm, the upper tolerance is 0, the lower tolerance is -0.2mm, the diameter d3 of the cylindrical surface 12 of the screw head is 3mm, the upper tolerance is 0, the lower tolerance is -0.05mm, the screw body is asymmetrical thread The top diameter d 1 of 23 is 1.8mm, the upper tolerance is +0.025mm, and the lower tolerance is -0.025mm. The aforementioned three dimensions are the basic dimensions of this embodiment, and the rest of the structural parameters of the screw are based on these parameters remain unchanged. Carry out optimal combination design.
本发明的螺钉由一组能够抵抗高扭矩的医用级生物兼容材料制成，该材料包括但不限于钛合金、钴铬和高强度树脂聚合物，在综合性能与应用成熟度上，优选钛合金，本实施例螺钉采用钛合金材质TC4(GB/T13810)制成。The screw of the present invention is made of a group of medical-grade biocompatible materials capable of resisting high torque, including but not limited to titanium alloy, cobalt-chromium and high-strength resin polymer, and titanium alloy is preferred in terms of comprehensive performance and application maturity , The screws of this embodiment are made of titanium alloy material TC4 (GB/T13810).
本发明的螺钉对螺纹的线程及旋向没有做严格的限制，可根据实际应用情况选择。一般而言，对于颅骨上固定的自攻螺钉，单线程螺纹的导入效率即可以满足要求，双线程螺纹理论上可增加导入效率，但实际导入过程中因螺纹与骨组织接触面增多，摩擦力增大，反而增大了螺钉的导入难度。此外，右旋螺纹则符合人们“顺时针旋转紧固，逆时针旋转放松”的习惯用法。因而，本实施例螺钉的螺纹为单线程右旋螺纹。The screw of the present invention does not impose strict restrictions on the thread and the direction of rotation of the thread, and can be selected according to actual application conditions. Generally speaking, for the self-tapping screw fixed on the skull, the introduction efficiency of single thread thread can meet the requirements, and the double thread thread can theoretically increase the introduction efficiency, but in the actual introduction process, due to the increase of the contact surface between the thread and the bone tissue, the friction force Increase, but increase the difficulty of screw introduction. In addition, right-hand threads are in line with the idiom that people "turn clockwise to tighten, and counterclockwise to loosen". Therefore, the thread of the screw in this embodiment is a single-thread right-hand thread.
螺钉头部锥面13的夹角θ 1至少为90°，以防止螺钉易被轴向拉出，建议θ 1 夹角在90°-120°之间取值，本实施例θ 1为100°。 The included angle θ1 of the taper surface 13 of the screw head is at least 90° to prevent the screw from being easily pulled out axially. It is recommended that the included angle θ1 be between 90° and 120°. In this embodiment, θ1 is 100° .
螺钉头部弧面11的圆弧直径为螺钉头部圆柱面直径d 3的2到3倍之间，螺钉头部弧面11的圆弧直径在6-9mm之间，优选的，本实施例螺钉头部弧面11的圆弧直径为6.36mm。 The diameter of the arc of the arc surface 11 of the screw head is between 2 and 3 times the diameter d3 of the cylindrical surface of the screw head, and the diameter of the arc of the arc surface 11 of the screw head is between 6-9 mm. Preferably, this embodiment The arc diameter of the arc surface 11 of the screw head is 6.36 mm.
如图2所示，螺钉头部十字形驱动槽111从弧面11中心处正交向外延伸，延伸长度介于螺钉头部圆柱面直径的60％-98％之间，最佳延伸长度为以保证不破坏钉头外圆完整性与结构强度下，提供螺钉最大驱动扭矩。十字形驱动槽111底部为弧形，以减少加工十字形驱动槽111时从螺钉头部1移除的材料量，并最大限度地保证螺钉头部的强度，十字形驱动槽111弧形底部的外圆半径r 1应介于螺钉头部圆柱面直径的90％-100％之间，十字形驱动槽111深度l在0.7-0.9mm之间。如图4所示，本实施例十字形驱动槽111延伸长度约2.90mm，十字形驱动槽111弧形底部的外圆半径r 1为2.75mm，十字形驱动槽111深度l为0.75mm。所述结构能够提供足够的扭矩，以允许螺钉被驱动到颅骨中，并具备足够的强度，以抵抗螺钉的头部与螺钉配套的力矩螺丝刀在安装期间的扭转变形。如果十字形驱动槽111延伸长度小于螺钉头部圆柱面直径的60％，则会导致螺丝刀不易配合，提供扭矩小；如果十字形驱动槽111延伸长度大于螺钉头部圆柱面直径的98％，则会导致螺钉头强度低，易变形。如果十字形驱动槽111外圆半径r 1小于螺钉头部圆柱面直径的90％，则会导致十字形驱动槽不易配合工具，易滑丝；如果十字形驱动槽111外圆半径r 1大于螺钉头部圆柱面直径，则会导致十字形驱动槽强度，易断裂。如果十字形驱动槽111的深度l小于0.7mm，则会导致十字形驱动槽不易配合工具，易滑丝；如果十字形驱动槽111的深度l大于0.9mm，则会导致十字形驱动槽强度，易断裂。 As shown in FIG. 2, the cross-shaped driving groove 111 of the screw head extends orthogonally outward from the center of the arc surface 11, and the extension length is between 60%-98% of the diameter of the cylindrical surface of the screw head, and the optimal extension length is In order to ensure the maximum driving torque of the screw without destroying the integrity of the outer circle of the nail head and the structural strength. The bottom of the cross-shaped drive slot 111 is arc-shaped to reduce the amount of material removed from the screw head 1 when machining the cross-shaped drive slot 111, and to maximize the strength of the screw head. The outer circle radius r 1 should be between 90%-100% of the diameter of the cylindrical surface of the screw head, and the depth l of the cross-shaped driving slot 111 should be between 0.7-0.9 mm. As shown in FIG. 4 , the extension length of the cross-shaped driving slot 111 in this embodiment is about 2.90 mm, the outer radius r1 of the arc bottom of the cross-shaped driving slot 111 is 2.75 mm, and the depth l of the cross-shaped driving slot 111 is 0.75 mm. The structure is capable of providing sufficient torque to allow the screw to be driven into the skull and sufficient strength to resist torsional deformation of the head of the screw and the torque driver for the screw during installation. If the extension length of the cross-shaped driving slot 111 is less than 60% of the diameter of the cylindrical surface of the screw head, it will cause the screwdriver to be difficult to fit and provide a small torque; It will lead to low strength of the screw head and easy deformation. If the outer radius r 1 of the cross-shaped drive slot 111 is less than 90% of the diameter of the cylindrical surface of the screw head, it will cause the cross-shaped drive slot to be difficult to fit with the tool and easy to slide the wire; if the outer radius r 1 of the cross-shaped drive slot 111 is larger than the screw The diameter of the cylindrical surface of the head will lead to the strength of the cross-shaped drive groove and it is easy to break. If the depth l of the cross-shaped driving slot 111 is less than 0.7mm, it will cause the cross-shaped driving slot to be difficult to fit the tool and easy to slide the wire; Fragile.
如图1所示，在螺钉头部1与螺钉主体2的连接处有一个圆倒角131，其圆角半径r 2在0-0.3mm之间。需指明的是，对于螺钉头部与固定器械接触面需严格平整接触的螺钉，其头部与主体连接处则不建议倒圆角。本实施例此处倒圆角是为了使螺钉头部1与螺钉主体2均匀过渡，避免应力集中，并使螺钉头部1的驱动扭矩更好地传递至螺钉主体2，其圆角r 2大小为0.3mm。 As shown in FIG. 1 , there is a rounded chamfer 131 at the connection between the screw head 1 and the screw body 2 , and the rounded corner radius r 2 is between 0-0.3 mm. It should be pointed out that for screws whose head and the contact surface of the fixation device need to be in strict and flat contact, rounding is not recommended at the connection between the head and the main body. In this embodiment, the rounded corners are used to make the transition between the screw head 1 and the screw body 2 evenly, to avoid stress concentration, and to better transmit the driving torque of the screw head 1 to the screw body 2. The rounded corners r 2 is 0.3mm.
螺钉主体2具有直形柱体22与锯齿状不对称螺纹23，直的柱体更有利于螺钉结构具备更好的强度。直形柱体22的外圆面与螺纹23的底径分型面相同，螺 钉主体2上各圈的螺纹23的顶径与底径分别相同。其中，在螺纹23顶径d 1保持1.8mm不变的情况下，螺纹23的底径d 2在1.2mm至1.3mm取得自攻性能与结构强度之间较佳的综合性能，本实施例螺纹23底径d 2为1.20mm。如果螺纹23的底径d 2小于1.2mm，则螺钉的强度低，容易断裂；如果螺纹23的底径d 2大于1.3mm，则螺钉的进给量小、不易攻丝。 The screw body 2 has a straight cylindrical body 22 and a serrated asymmetrical thread 23, and the straight cylindrical body is more conducive to the screw structure having better strength. The outer circular surface of the straight cylinder 22 is the same as the bottom diameter parting surface of the thread 23 , and the top diameter and the bottom diameter of the threads 23 of each circle on the screw body 2 are respectively the same. Among them, under the condition that the top diameter d1 of the thread 23 remains unchanged at 1.8mm, the bottom diameter d2 of the thread 23 is 1.2mm to 1.3mm to obtain a better comprehensive performance between self-tapping performance and structural strength. 23 The bottom diameter d 2 is 1.20mm. If the bottom diameter d 2 of the thread 23 is less than 1.2 mm, the strength of the screw is low and it is easy to break; if the bottom diameter d 2 of the thread 23 is greater than 1.3 mm, the feed rate of the screw is small and it is difficult to tap.
螺钉主体2的螺纹牙型如图5所示。牙体底部倒角半径r 3与r 4的大小主要影响螺纹的强度，牙体牙侧角α与β的大小主要影响螺纹的切削效率，牙体顶部的倒角半径r 5与类脊状平台宽度e的大小同时影响螺纹的强度与切削效率，且受螺钉本身材质硬度与所切削骨组织的硬度有关，螺钉材质和骨组织的硬度越大，牙体顶部的倒角半径r 5与类脊状平台宽度e应越小。本实施例在综合分析后，对牙型各结构参数进行了优化，包括：靠近螺钉尾端一侧的牙体底部倒角半径r 3优选的取值范围为0.25-0.3mm，靠近螺钉头部一侧的牙体底部倒角半径r 4优选的取值范围为0.05-0.1mm，靠近螺钉头部一侧的牙体牙侧角α优选的取值范围为3°-5°，靠近螺钉尾端一侧的牙体牙侧角β优选的取值范围为32°-38°，牙体顶部的倒角半径r 5优选的取值范围为0-0.05mm，类脊状平台宽度e优选的取值范围为0.05-0.15mm。在本实施例中，选择的牙型各结构参数为：牙体底部倒角r 3与r 4分别为0.3mm、0.1mm，牙体牙侧角α与β分别为3°、35°，牙体顶部的倒角r 5与类脊状平台宽度e分别为0.05mm、0.1mm。如果牙体底部倒角半径r 3小于0.25mm，则会导致螺钉的强度低，螺钉易断裂，如果牙体底部倒角半径r 3大于0.3mm，则会导致螺钉的阻力面大，不易攻丝的问题。同样的，如果牙体底部倒角半径r 4小于0.05mm，则会导致螺钉的强度低，螺钉易断裂；如果牙体底部倒角半径r 4大于0.1mm，则会导致螺钉的阻力面大，不易攻丝的问题。如果牙体牙侧角α小于3°，则会导致螺钉的进给量小，攻丝效率低的问题；如果牙体牙侧角α大于5°，则会导致螺钉进给量过大，所受进给阻力大，不易攻丝的问题。同样的，如果牙体牙侧角β小于32°，则会导致螺钉的进给量小，攻丝效率低的问题；如果牙体牙侧角β大于38°，则会导致螺钉进给量过大，所受进给阻力大，不易攻丝的问题。如果类脊状平台宽度e小于0.05mm，则螺钉强度低，易断裂；如果类脊状平台宽度e大于0.15mm，则螺钉进给阻力大，不易攻丝。如果牙体顶部的倒角r 5大于0.05mm，则会使得类脊状平台宽度过小，容易断裂。 The thread profile of the screw body 2 is shown in Figure 5 . The chamfering radii r 3 and r 4 at the bottom of the tooth mainly affect the strength of the thread, the flank angles α and β of the tooth mainly affect the cutting efficiency of the thread, and the chamfering radius r 5 at the top of the tooth is related to the ridge-like platform. The size of the width e affects the strength and cutting efficiency of the thread at the same time, and is affected by the hardness of the screw itself and the hardness of the bone tissue to be cut. The width e of the shape platform should be smaller. After comprehensive analysis in this embodiment, various structural parameters of the tooth shape are optimized, including: the preferred value range of the chamfering radius r 3 at the bottom of the tooth body close to the end of the screw is 0.25-0.3 mm, and it is close to the head of the screw. The preferred value range of the chamfering radius r 4 at the bottom of the tooth on one side is 0.05-0.1 mm, and the preferred value range of the tooth flank angle α on the side close to the screw head is 3°-5°, close to the screw tail The preferred value range of the tooth flank angle β on the end side is 32°-38°, the preferred value range of the chamfer radius r 5 of the tooth top is 0-0.05mm, and the preferred ridge-like platform width e is The value range is 0.05-0.15mm. In this embodiment, the selected structural parameters of the tooth type are: the bottom chamfers r 3 and r 4 of the tooth are 0.3 mm and 0.1 mm respectively, the flank angles α and β of the tooth are 3° and 35° respectively, The chamfer r5 at the top of the body and the width e of the ridge - like platform are 0.05mm and 0.1mm, respectively. If the chamfering radius r3 at the bottom of the tooth body is less than 0.25mm, the strength of the screw will be low, and the screw will be easily broken. If the chamfering radius r3 at the bottom of the tooth body is greater than 0.3mm, the resistance surface of the screw will be large and it will be difficult to tap. The problem. Similarly, if the chamfer radius r 4 at the bottom of the tooth is less than 0.05mm, the strength of the screw will be low, and the screw will be easily broken; if the chamfer radius r 4 at the bottom of the tooth is greater than 0.1mm, the resistance surface of the screw will be large, The problem of not easy tapping. If the tooth flank angle α is less than 3°, the screw feed will be small and the tapping efficiency will be low; if the tooth flank angle α is greater than 5°, the screw feed will be too large. Due to the large feeding resistance, it is not easy to tap. Similarly, if the tooth flank angle β is less than 32°, the screw feed will be small and the tapping efficiency will be low; if the tooth flank angle β is greater than 38°, the screw feed will be excessive. Large, the feeding resistance is large, and it is not easy to tap. If the width e of the ridge-like platform is less than 0.05mm, the strength of the screw is low and it is easy to break; if the width e of the ridge-like platform is greater than 0.15mm, the screw feed resistance is large and it is not easy to tap. If the chamfer r 5 at the top of the tooth is larger than 0.05mm, the width of the ridge-like platform will be too small and it will be easy to break.
螺钉尾端3包括类椎体33和类椎体上的渐变螺纹31，类椎体33与渐变螺纹31结构有利于螺钉尾端3的导入与攻丝，渐变螺纹31上的出屑槽32有利于导出或容纳骨组织碎屑，以减少螺钉受到骨组织材料的阻力，从而降低螺钉的旋入扭矩。出屑槽32穿过螺纹的圈数视螺钉的结构强度而定，在螺钉强度满足要求的前提下，穿过的螺纹圈数越多越有利于碎屑的导出。如图3所示，出屑槽32上的刮削刃321还具有刮削螺纹形状的作用，其刮削效果受出屑槽截面夹角θ 3的大小影响。理论上，出屑槽截面夹角θ 3在45°-120°范围内，其角度越小，刮削效果越好。需指明的是，出屑槽截面夹角θ 3的大小还影响着出屑的速率，理论上，在45°-120°范围内，其夹角越大，出屑效率越快。综合地，出屑槽截面夹角尺寸θ 3在75°-112°之间取得较优值。本实施例螺钉的出屑槽截面夹角尺寸θ 3为90°。如果出屑槽截面夹角尺寸θ 3小于75°，则会出现容屑少或出屑慢，螺钉进给阻力大，不易攻丝的问题；如果出屑槽截面夹角尺寸θ 3大于112°，则会出现螺钉强度低，容易断裂的问题。 The screw tail end 3 includes a cone-like body 33 and a gradient thread 31 on the cone-like body. The structure of the cone-like body 33 and the gradient thread 31 is conducive to the introduction and tapping of the screw tail end 3. The chip groove 32 on the gradient thread 31 has It is beneficial to export or accommodate bone tissue debris, so as to reduce the resistance of the screw to the bone tissue material, thereby reducing the screw-in torque. The number of turns of the chip flute 32 passing through the thread depends on the structural strength of the screw. On the premise that the strength of the screw meets the requirements, the more the number of turns of the thread passing through, the more conducive to the export of chips. As shown in FIG. 3 , the scraping edge 321 on the chip flute 32 also has the function of scraping the thread shape, and the scraping effect is affected by the size of the included angle θ 3 of the chip flute section. Theoretically, the included angle θ3 of the flute section is in the range of 45°-120°, and the smaller the angle, the better the scraping effect. It should be pointed out that the size of the included angle θ3 of the chip flute section also affects the rate of chip ejection. In theory, within the range of 45°-120°, the larger the included angle, the faster the chip ejection efficiency. In general, the angle dimension θ3 of the chip flute section is between 75°-112° to obtain a better value. The included angle dimension θ3 of the chip flute section of the screw in this embodiment is 90°. If the included angle dimension θ3 of the chip flute section is less than 75°, there will be problems such as less chip capacity or slow chip ejection, high screw feeding resistance, and difficulty in tapping; if the included angle dimension θ3 of the chip flute section is greater than 112° , there will be problems of low screw strength and easy breakage.
螺钉的渐变螺纹31具有均匀过渡的顶径与底径，在同时考虑到骨质及螺钉材质的硬度情况下，其顶尖角θ 2在48°-65°之间取得螺钉钻孔效率与螺钉尾端强度的较优平衡值。本实施例螺钉尾端的顶尖角θ 2为60°。如果顶尖角的角度小于48°，则螺钉尾端的强度低，易断裂；如果顶尖角的角度大于65°，则螺钉尾端难进给，不易攻丝。 The gradient thread 31 of the screw has a uniform transition top diameter and bottom diameter. Taking into account the hardness of the bone and the material of the screw at the same time, its tip angle θ 2 is between 48°-65° to obtain the screw drilling efficiency and screw tail. The optimal balance of end strength. The tip angle θ 2 of the tail end of the screw in this embodiment is 60°. If the angle of the tip angle is less than 48°, the strength of the tail end of the screw is low and it is easy to break; if the angle of the tip angle is greater than 65°, the tail end of the screw is difficult to feed and difficult to tap.
螺钉主体2和螺钉尾端3具有相同的螺距P。螺距P的大小设计优化的依据如下：The screw body 2 and the screw tail 3 have the same pitch P. The basis for the design optimization of the pitch P is as follows:
螺钉螺距P的大小与力矩螺丝刀的驱动力矩M、传递效率ε、轴向输出力F之间的关系可近似为：F＝(2π·ε·M)/P。当驱动力矩M与传递效率ε一定时，螺距P与轴向输出力成反比，即螺距P越小，轴向输出力F越大，螺钉骨内进给力越大；当轴向输出力F与传递效率ε一定时，螺距P与驱动力矩M成正比，即螺距P越小，所需的驱动力矩M越小，螺钉旋入扭矩越小。因此，要想在小驱动扭矩下输出较大的轴向输出力，螺钉的螺距P应尽可能小。The relationship between the screw pitch P and the driving torque M of the torque screwdriver, the transmission efficiency ε, and the axial output force F can be approximated as: F=(2π·ε·M)/P. When the driving torque M and the transmission efficiency ε are constant, the thread pitch P is inversely proportional to the axial output force, that is, the smaller the thread pitch P, the greater the axial output force F, and the greater the feed force in the screw bone; when the axial output force F and When the transmission efficiency ε is constant, the pitch P is proportional to the driving torque M, that is, the smaller the pitch P, the smaller the required driving torque M, and the smaller the screw-in torque. Therefore, in order to output a large axial output force under a small driving torque, the pitch P of the screw should be as small as possible.
然而，螺钉的进给量W与螺钉的螺距P相等，即当驱动速率一定时，螺距P越小，螺钉的进给量W越小，与之对应的临床操作表现为：医生驱动小螺距螺钉的力矩很小，但相应的该螺钉的攻丝速率慢，医生需旋动更多的圈数将螺钉完 全固定。However, the feed amount W of the screw is equal to the pitch P of the screw, that is, when the driving rate is constant, the smaller the pitch P, the smaller the feed amount W of the screw, and the corresponding clinical operation is as follows: the doctor drives the small pitch screw The torque of the screw is small, but the tapping rate of the screw is correspondingly slow, and the doctor needs to rotate more turns to completely fix the screw.
因此，螺钉的螺距P应在一定范围内取得某个中间值，使得螺钉的驱动力矩较小，而旋入速率较快。本实施例螺距P在0.60-0.75mm取得较优值，本实施例的优选例螺钉螺距P为0.70mm。如果螺距P小于0.60mm，则螺钉的进给量小，攻丝效率慢；如果螺距P大于0.75mm，则螺钉进给阻力大，不易攻丝。Therefore, the pitch P of the screw should obtain a certain intermediate value within a certain range, so that the driving torque of the screw is small and the screwing rate is fast. In this embodiment, the screw pitch P is preferably 0.60-0.75 mm, and the screw pitch P in the preferred example of this embodiment is 0.70 mm. If the pitch P is less than 0.60mm, the feed rate of the screw is small and the tapping efficiency is slow; if the pitch P is greater than 0.75mm, the screw feeding resistance is large and it is not easy to tap.
图6与图7分别为本发明实施例颅骨螺钉相配套的力矩螺丝刀4的局部侧视图与端部视图。如图6与图7所示，力矩螺丝刀4的十字形刀头41与螺钉头部十字形槽驱动槽111配合安装，旋入时保持螺丝刀平稳，旋入速度低速稳定，操作人员操作规范。6 and 7 are respectively a partial side view and an end view of a torque screwdriver 4 matched with a skull screw according to an embodiment of the present invention. As shown in Figures 6 and 7, the cross-shaped bit 41 of the torque screwdriver 4 is installed in conjunction with the cross-shaped groove driving slot 111 of the screw head. When screwing in, the screwdriver is kept stable, the screwing speed is low and stable, and the operator operates in a standardized manner.
本发明的螺钉可以很容易地使用能够切削螺纹的现代车床制造，也可采用CNC一次性加工成型，螺钉表面去毛刺，光洁处理，阳极氧化。螺钉扭矩测试和断裂扭转角按照YY/T0662规定方法进行测试，最大扭矩≥0.5N·m，最大断裂扭转角≥150°。螺钉材质硬度按照GB/T4340.1规定的方法进行测定，材质硬度≥260HV。螺钉旋动扭矩按照YY/T1506-2016进行测试，平均旋入扭矩0.25N·m。The screw of the present invention can be easily manufactured by using a modern lathe capable of cutting threads, and can also be processed and formed at one time by CNC, and the surface of the screw is deburred, polished and anodized. The screw torque test and fracture torsion angle are tested according to the method specified in YY/T0662, the maximum torque is ≥0.5N m, and the maximum fracture torsion angle is ≥150°. The hardness of the screw material is measured according to the method specified in GB/T4340.1, and the material hardness is greater than or equal to 260HV. The screw torque is tested according to YY/T1506-2016, and the average screw-in torque is 0.25N m.
本发明的螺钉与传统颅骨螺钉在牛骨上进行自攻性能与强度测试对比，能在更低扭矩值下完全顺利旋入牛骨中，螺钉无裂纹。定量对比实验中，在试验条件相同情况下，传统颅骨螺钉实测平均完全旋入扭矩值为0.282N.m，优选实施例颅骨螺钉实测平均旋入扭矩值为0.226N.m，相对于传统颅骨螺钉，优选实施例颅骨螺钉的自攻性能优化率为19.8％；传统颅骨螺钉实测平均断裂扭矩为0.49N.m，优选实施例颅骨螺钉实测平均断裂扭矩为0.51N.m，相对于传统颅骨螺钉，优选实施例颅骨螺钉的结构强度优化率为4％。由于优选实施例颅骨螺钉相对传统颅骨螺钉有更好的自攻性能，导入阻力小，因此实际攻丝过程中发生断裂的可能性更小，其自攻性能与结构强度表现优于传统的颅骨螺钉。The self-tapping performance and strength test of the screw of the invention and the traditional skull screw on the bovine bone can be completely and smoothly screwed into the bovine bone under a lower torque value, and the screw has no cracks. In the quantitative comparison experiment, under the same test conditions, the measured average complete screw-in torque value of the traditional skull screw is 0.282N.m, and the measured average screw-in torque value of the preferred embodiment skull screw is 0.226N.m. Compared with the traditional skull screw, the preferred embodiment The self-tapping performance optimization rate of the skull screw is 19.8%; the measured average breaking torque of the traditional skull screw is 0.49N.m, and the measured average breaking torque of the skull screw of the preferred embodiment is 0.51N.m. Compared with the traditional skull screw, the structural strength of the skull screw of the preferred embodiment The optimization rate is 4%. Because the skull screw of the preferred embodiment has better self-tapping performance compared with the traditional skull screw, and the introduction resistance is small, the possibility of fracture during the actual tapping process is smaller, and its self-tapping performance and structural strength are better than the traditional skull screw. .
以上对本发明所提供的颅骨螺钉进行了描述。本文中应用了具体个例对本发明的原理及实施方式进行了阐述，以上实施例的说明只是用于帮助理解本发明的方法及其核心思想，并不用于限制本发明。因此，对于本技术领域的普通技术人员来说，凡在本发明的精神和原理之内所做的任何修改，应包含在本发明的保护范围之内。The skull screw provided by the present invention has been described above. The principles and implementations of the present invention are described herein by using specific examples. The descriptions of the above embodiments are only used to help understand the method and the core idea of the present invention, and are not intended to limit the present invention. Therefore, for those skilled in the art, any modifications made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims (10)

  1. 一种颅骨螺钉，其特征在于，包括：A skull screw, characterized in that it comprises:
    螺钉头部(1)，包括弧面(11)、圆柱面(12)与锥面(13)；The screw head (1) includes an arc surface (11), a cylindrical surface (12) and a conical surface (13);
    螺钉主体(2)，包括直形柱体(22)和直形柱体上的锯齿状不对称螺纹(23)；a screw body (2), comprising a straight cylinder (22) and a serrated asymmetric thread (23) on the straight cylinder;
    螺钉尾端(3)，包括类椎体(33)和类椎体上的渐变螺纹(31)；The tail end of the screw (3) includes a vertebral body (33) and a gradient thread (31) on the vertebral body;
    所述螺钉主体(2)和所述螺钉尾端(3)的螺距P为0.60-0.75mm；The pitch P of the screw main body (2) and the screw tail end (3) is 0.60-0.75mm;
    所述渐变螺纹(31)具有均匀过渡的顶径与底径，所述类椎体(33)的顶尖角θ 2为48°-65°。 The tapered thread (31) has a top diameter and a bottom diameter of uniform transition, and the tip angle θ2 of the cone - like body (33) is 48°-65°.
  2. 根据权利要求1所述的螺钉，其特征在于，所述底径d 2的尺寸为1.2-1.3mm。 The screw according to claim 1, wherein the size of the bottom diameter d 2 is 1.2-1.3 mm.
  3. 根据权利要求2所述的螺钉，其特征在于，所述直形柱体(22)的外圆面与所述锯齿状不对称螺纹(23)的底径分型面相同；所述锯齿状不对称螺纹(23)在各圈上的顶径与底径分别相同。The screw according to claim 2, characterized in that, the outer circular surface of the straight cylinder (22) is the same as the bottom diameter parting surface of the serrated asymmetric thread (23); The top diameter and bottom diameter of the symmetrical thread (23) on each circle are respectively the same.
  4. 根据权利要求1-3中任一项所述的螺钉，其特征在于，所述锯齿状不对称螺纹(23)与所述渐变螺纹(31)均具有特制的牙体结构，所述牙体结构牙体顶部具有较窄的类脊状平台(233)，所述类脊状平台(233)宽度e为0.05-0.15mm。The screw according to any one of claims 1-3, characterized in that both the serrated asymmetrical thread (23) and the gradual thread (31) have a specially designed tooth structure, and the tooth structure The top of the tooth has a narrow ridge-like platform (233), and the width e of the ridge-like platform (233) is 0.05-0.15 mm.
  5. 根据权利要求4所述的螺钉，其特征在于，The screw of claim 4, wherein
    所述牙体顶部倒角半径r 5为0-0.05mm；和/或， The chamfering radius r 5 of the top of the tooth is 0-0.05 mm; and/or,
    所述牙体结构靠近所述螺钉头部(1)一侧的牙体牙侧角α为3°-5°；和/或，The tooth flank angle α on the side of the tooth structure close to the screw head (1) is 3°-5°; and/or,
    所述牙体结构靠近所述螺钉尾端(3)一侧的牙体牙侧角β为32°-38°。The tooth flank angle β on the side of the tooth structure close to the screw tail end (3) is 32°-38°.
  6. 根据权利要求4所述的螺钉，其特征在于，The screw of claim 4, wherein
    所述牙体结构靠近所述螺钉尾端(3)一侧的牙体底部倒角(231)，所述牙体底部倒角(231)的半径r 3为0.25-0.3mm；和/或， The tooth bottom chamfer (231) on the side of the tooth structure close to the screw tail end ( 3 ), the radius r3 of the tooth bottom chamfer (231) is 0.25-0.3 mm; and/or,
    所述牙体结构靠近所述螺钉头部(1)一侧的牙体底部倒角(232)，所述牙体底部倒角(232)的半径r 4为0.05-0.1mm。 A tooth bottom chamfer (232) on the side of the tooth structure close to the screw head (1), and a radius r 4 of the tooth bottom chamfer (232) is 0.05-0.1 mm.
  7. 根据权利要求1-6中任一项所述的螺钉，其特征在于，所述螺钉尾端(3)包括一个出屑槽(32)，所述出屑槽(32)穿过多圈螺纹，所述多圈螺纹的圈数不少于2圈，所述出屑槽(32)的截面夹角θ 3为75°-112°，且包括具有刮削作用的刮削刃(321)。 The screw according to any one of claims 1-6, characterized in that, the screw tail end (3) comprises a chip flute (32), and the chip flute (32) passes through multiple turns of thread, The number of turns of the multi-turn thread is not less than 2 turns, the section angle θ3 of the chip flute (32) is 75°-112°, and a scraping edge (321) with scraping function is included.
  8. 根据权利要求1-7中任一项所述的螺钉，其特征在于，所述弧面(11)的 中心处设置有用于螺钉连接时作为驱动接口的十字形驱动槽(111)，所述十字形驱动槽(111)从弧面中心处正交向外延伸，延伸长度介于所述圆柱面(12)直径d 3的60％-98％；和/或， The screw according to any one of claims 1-7, characterized in that, a cross-shaped driving slot (111) used as a driving interface for screw connection is provided at the center of the arc surface (11), and the ten The word-shaped driving groove (111) extends orthogonally outward from the center of the arc surface, and the extension length is between 60%-98% of the diameter d3 of the cylindrical surface (12); and/or,
    所述十字形驱动槽(111)弧形底部的半径r 1为所述圆柱面(12)直径d 3的90％-100％；和/或， The radius r 1 of the arc bottom of the cross-shaped driving groove (111) is 90%-100% of the diameter d 3 of the cylindrical surface (12); and/or,
    所述十字形驱动槽(111)的深度l为0.7-0.9mm。The depth l of the cross-shaped driving groove (111) is 0.7-0.9 mm.
  9. 根据权利要求1-8中任一项所述的螺钉，其特征在于，所述螺钉主体(2)和所述螺钉尾端(3)的螺纹为单线程右旋螺纹。The screw according to any one of claims 1-8, characterized in that, the threads of the screw body (2) and the screw tail end (3) are single-thread right-hand threads.
  10. 根据权利要求1-9中任一项所述的螺钉，其特征在于，所述螺钉整体长度为5.8-6mm；所述螺钉头部圆柱面(12)的直径d 3为2.95-3mm；所述螺钉主体不对称螺纹(23)的顶径d 1为1.775-1.825mm。 The screw according to any one of claims 1-9, characterized in that, the overall length of the screw is 5.8-6 mm; the diameter d 3 of the cylindrical surface (12) of the screw head is 2.95-3 mm; the The top diameter d 1 of the asymmetric thread (23) of the screw body is 1.775-1.825 mm.
PCT/CN2020/141955 2020-09-30 2020-12-31 Cranial screw WO2022068118A1 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN216629427U (en) * 2021-12-17 2022-05-31 苏州景昱医疗器械有限公司 Skull nail and brain electrode fixing assembly

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070083206A1 (en) * 2005-09-21 2007-04-12 Microware Precision Co., Ltd. Self drilling and tapping bone screw
CN102188282A (en) * 2010-03-08 2011-09-21 史赛克创伤公司 Bone fixation system with curved profile threads
CN202409140U (en) * 2011-11-29 2012-09-05 天津市康尔医疗器械有限公司 Short skull screw
CN204744455U (en) * 2015-06-11 2015-11-11 大连大学 Orthodontic body with asymmetric helicitic texture
CN107280756A (en) * 2017-07-21 2017-10-24 西安康拓医疗技术有限公司 A kind of medical cranial Bone nail structure
CN208435757U (en) * 2017-12-12 2019-01-29 上海伍健医疗器械有限公司 A kind of traditional method of indicating the pronunciation of a Chinese character self tapping bone nail
CN210811451U (en) * 2019-09-20 2020-06-23 苏州市美新迪斯医疗科技有限公司 Degradable magnesium alloy bone fixing screw

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE523765C2 (en) * 2000-07-12 2004-05-18 Entific Medical Systems Ab Screw-shaped anchoring element for permanent anchoring of leg anchored hearing aids and ear or eye prostheses in the skull
US20040044345A1 (en) * 2002-08-28 2004-03-04 Demoss Richard Marshal Shallow penetration bone screw
US20050021036A1 (en) * 2003-07-21 2005-01-27 Whitmore Robin C. Self-drilling, self-tapping bone screw
DE10361044B4 (en) * 2003-12-23 2005-12-29 Stryker Leibinger Gmbh & Co. Kg Self-drilling bone screw and implant system
US20110218580A1 (en) * 2010-03-08 2011-09-08 Stryker Trauma Sa Bone fixation system with curved profile threads
CN103550859B (en) * 2013-11-07 2015-06-24 北京品驰医疗设备有限公司 Fixing device for medical apparatuses and instruments
CN104257424A (en) * 2014-08-21 2015-01-07 赵德伟 Full-thread degradable pure-magnesium bolt
EP3560449A1 (en) * 2014-11-04 2019-10-30 DePuy Synthes Products, Inc. Blunt tip bone screw
CN104941065B (en) * 2015-06-30 2018-02-27 北京品驰医疗设备有限公司 Implantable neural electrical stimulator and the protective case applied to the implantable neural electrical stimulator

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070083206A1 (en) * 2005-09-21 2007-04-12 Microware Precision Co., Ltd. Self drilling and tapping bone screw
CN102188282A (en) * 2010-03-08 2011-09-21 史赛克创伤公司 Bone fixation system with curved profile threads
CN202409140U (en) * 2011-11-29 2012-09-05 天津市康尔医疗器械有限公司 Short skull screw
CN204744455U (en) * 2015-06-11 2015-11-11 大连大学 Orthodontic body with asymmetric helicitic texture
CN107280756A (en) * 2017-07-21 2017-10-24 西安康拓医疗技术有限公司 A kind of medical cranial Bone nail structure
CN208435757U (en) * 2017-12-12 2019-01-29 上海伍健医疗器械有限公司 A kind of traditional method of indicating the pronunciation of a Chinese character self tapping bone nail
CN210811451U (en) * 2019-09-20 2020-06-23 苏州市美新迪斯医疗科技有限公司 Degradable magnesium alloy bone fixing screw

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