Device and method for fixing and restoring skull flap
By designing a device for fixing and releasing the skull bone flap, the skull side fixing end, first titanium nail, lifting structure and other components can be used to adjust the defective flap, which solves the problem that traditional fixation systems cannot reduce intracranial pressure. The problem of this is to achieve stable reduction of intracranial pressure and stable fixation of bone flap.
Patent Information
- Application Number
- CN202411620395.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-14
- Publication Date
- 2025-02-07
AI Technical Summary
The traditional skull fixation system cannot achieve a stable reduction in intracranial pressure without removing the bone flap, resulting in the possibility of increased intracranial pressure after surgery, which increases the risk and financial burden of the patient.
A device for fixing and releasing the skull bone flap is designed, which includes a skull fixator and a defective flap, through a skull side fixing end, a first titanium nail, an elevation structure, an adjusting boss, and a skull side fixing end The combination with fixed titanium nails can achieve lifting and descending of the defective bone flap, and adjust the distance between the skulls to reduce intracranial pressure.
This device can not only replace the traditional simple fixation device, reduce the adverse consequences of postoperative intracranial pressure, but also stabilize control intracranial pressure without performing a second operation, and improve the patient's prognosis and rehabilitation effect.
Smart Images
Figure CN119385723A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of bone fixation and repair, and in particular to a device and method for fixation and reduction of a skull bone flap. Background Art
[0002] The fields of bone fixation and repair include neurosurgery, maxillofacial surgery, thoracic and cardiovascular surgery, orthopedics, etc. For example, neurosurgery craniotomy involves the return and fixation of the skull after surgery. Originally, the skull connection mainly relied on silk thread fixation. Later, the skull lock fixation method gradually emerged, that is, two metal discs were used to lock the skull from inside and outside the skull to play a fixing role, but this method has the risk of postoperative epidural hematoma. Later, the skull was fixed by bone connecting pieces, that is, the free bone flap and the surrounding bone edge were fixed outside the skull with bone screws and bone connecting pieces. It mainly requires the use of a manual screwdriver to fix at least three connecting pieces to the free bone flap with screws, then the skull is returned, and then the other end of the connecting piece is fixed to the surrounding bone edge with a manual screwdriver. After decades of development, the main method is still to use titanium alloy bone connecting pieces and fix them to the inside of the bone tissue with screws.
[0003] Although the traditional fixation method completely preserves the bone flap and skull structure, it cannot achieve the purpose of decompression. When a person's cranial sutures are basically closed at around 1.5 years old, the cranial cavity becomes a closed and relatively fixed "large container". This "large container" mainly includes brain tissue (1400g), cerebrospinal fluid (75ml) and blood (75ml). Under normal circumstances, the total volume of these three maintains a dynamic balance with the total volume of the "large container" to maintain the intracranial pressure at a normal level. Since the volume of brain tissue is relatively constant, especially when acute intracranial pressure increases, it cannot be compressed. The regulation of intracranial pressure is to maintain a balance between the cerebral blood volume and the cerebrospinal fluid volume. Cerebrospinal fluid is the most variable component. The amount of cerebrospinal fluid in the ventricles, cerebral cisterns and cranial subarachnoid space is about 75ml, accounting for about 5.5% of the cranial cavity volume. When intracranial hypertension occurs, the cerebrospinal fluid first reduces secretion, increases absorption and is partially compressed out of the skull to relieve the increased intracranial pressure, followed by compression of cerebral blood volume. Therefore, the compensatory volume available to relieve intracranial hypertension is about 8% of the cranial cavity volume. Therefore, when the increased volume of pathological phenomena such as cerebral hemorrhage, extensive cerebral contusion and laceration, severe cerebral edema, large-area cerebral infarction, diffuse brain swelling, brain tumors, etc. exceeds the compensatory volume of the cranial cavity, intracranial hypertension may occur. If intracranial pressure continues to rise, it may cause disorders in the cerebral blood flow regulation function, severe ischemia and hypoxia of brain tissue, aggravated cerebral edema, increased brain tissue volume, and increased intracranial pressure, which may cause brain tissue displacement to form brain herniation, and eventually cause brainstem compression, respiratory and circulatory center failure and death.
[0004] In clinical work, craniectomy is performed for heavier patients with severe intracranial hypertension, and cranioplasty is performed for mild patients such as unruptured aneurysms. Early maintenance of normal intracranial pressure and reduction of complications caused by high intracranial pressure are the key to improving patient prognosis after surgery. However, for patients suspected of delayed intracranial hypertension after intracranial surgery, there is no device that can achieve the effect of primary decompression under the premise of normal skull restoration structure stability. Usually, the surgeon decides whether to keep the bone flap based on the actual situation of the patient and the intraoperative situation. Among patients who retain the bone flap, there are many patients whose prognosis is reduced or even undergoes a second operation due to increased intracranial pressure after surgery. After craniectomy, the second-stage cranioplasty not only causes secondary trauma to the patient and increases the risk of infection and anesthesia, but also imposes a heavier economic burden.
[0005] In summary, the traditional skull fixation system can only simply restore and fix the bone flap. Since there is no third option, surgeons often remove the bone flap to ensure patient safety. During the recovery process of cerebral edema in patients who retain the bone flap, the brain tissue may be restricted by the bone flap and thus affect the prognosis. Summary of the invention
[0006] The purpose of the present invention is to provide a device and method for fixation and reduction of a skull bone flap, which can not only completely replace the traditional simple fixation device, but also reduce the adverse consequences caused by intracranial pressure after surgery and stabilize the intracranial pressure without a second operation.
[0007] To achieve the above purpose, the technical solution adopted by the present invention is as follows:
[0008] A device for fixing and reducing a skull bone flap comprises a skull fixer and a defective bone flap, wherein the skull fixer is used to fix the defective bone flap on the skull; the skull fixer comprises a skull side fixing end, a first titanium nail, a lifting structure, an adjusting boss, a bone flap side fixing end and a fixing titanium nail; the skull side fixing end is fixedly connected to the bone flap side fixing end; the skull side fixing end is fixed to the skull through the fixing titanium nail; the adjusting boss is arranged on the bone flap side fixing end, and the first titanium nail passes through the defective bone flap and the lifting structure in sequence and is screwed together with the adjusting boss, so as to fix the defective bone flap and the bone flap side fixing end together.
[0009] Furthermore, the skull side fixing end is a semi-cylindrical structure with a radius of 5 mm, and a skull fixing hole is arranged at its center, and the fixing titanium nail fixes the skull side fixing end to the skull through the fixing hole; the arc surface of the skull side fixing end faces the skull side, and a semi-cylindrical through groove adapted to it is opened at a corresponding position of the skull, and the skull side fixing end is embedded in the through groove and fixed by the fixing titanium nail; the fixing titanium nail extends out of the skull side fixing end and is fixed in the skull.
[0010] Furthermore, the bone flap side fixing end is a scale-type structure, and an adjustment boss is arranged at its center. The adjustment boss is a cylindrical structure with an internal thread. The first titanium nail is screwed into the adjustment boss to fix the bone flap side fixing end and the defective bone flap together.
[0011] Furthermore, the lifting structure is a spring made of medical stainless steel or titanium alloy, which is sleeved on the first titanium nail and placed between the defective bone flap and the adjustment boss; the first titanium nail passes through the defective bone flap and the lifting structure in sequence and is fixed on the adjustment boss.
[0012] Furthermore, the number of the skull fixators is 3-6, preferably 3, and they are positioned and installed in a three-point (triangle) or multi-point symmetrical manner, and can be dynamically adjusted according to the patient's condition to meet the needs of different patients.
[0013] Furthermore, the skull side fixed end is a semi-cylindrical structure with a radius of 5 mm; the bone flap side fixed end is a scaly structure with a length of 10 mm and a width of 8 mm; the inner diameter of the adjusting boss is 3 mm, the outer diameter is 4 mm, and the height is 6 mm; the lifting structure is a spring with an inner diameter of 4.5 mm and a minimum compression length of 2 mm; the adjusting boss has a 6 mm limit to prevent the adverse consequences of damaging the brain tissue due to excessive tightening force and excessive rotation stroke of the first titanium nail.
[0014] Furthermore, the cylindrical end radius of the first titanium nail and the fixing titanium nail is 1.5 mm and the length is 8 mm; by adjusting the rotation of the first titanium nail (clockwise or counterclockwise) to compress the lifting structure to different degrees, the defective bone flap can be lifted or lowered; the maximum lifting is 6 mm, and the descent does not exceed the lowest point of the skull fixator.
[0015] Furthermore, the lifting structure can lift the defective bone flap by rotating the first titanium nail clockwise through its elastic force; by rotating the first titanium nail counterclockwise, the defective bone flap can be lowered by compressing the lifting structure, thereby reducing the distance between the defective bone flap and the skull; the diameter of the head of the first titanium nail should be larger than the diameter of the lifting structure; the maximum elastic force of the lifting structure should be less than the maximum bearing capacity of the first titanium nail.
[0016] Furthermore, the skull side fixing end, the first titanium nail, the lifting structure, the adjusting boss, the bone flap side fixing end and the fixing titanium nail are all made of medical titanium alloy.
[0017] The method for fixing and reducing a skull bone flap using the above-mentioned device is to dynamically adjust the skull fixator according to the patient's physical condition, and adopt three-point or multi-point symmetrical fixation to fix each skull fixator to the defective bone flap and the skull respectively; then adjust the first titanium screw to rotate clockwise or counterclockwise to drive the defective bone flap to rise or fall, thereby adjusting the distance between the defective bone flap and the skull.
[0018] The patented design principle and beneficial effects of this invention are as follows:
[0019] The present invention is a device for fixing and reducing a skull bone flap, and is also a device and method for pre-elevating the fixation of a bone hole in cranial surgery, which solves the problem that the traditional skull fixation system cannot decompress. At the same time, the device is stronger than the traditional nail plate fixation system and the skull lock system, ensuring the stability of the bone flap after reduction. The device can achieve the lifting of the defective bone flap by adjusting the first titanium nail, and can be reduced normally according to the rotation path, with a certain tension. When the intracranial pressure is normal, it is not affected by gravity and other forces. Considering the thickness of the patient's skull, a titanium mesh can be used to replace the skull for repair in the first stage. After 3 months after surgery, it can be stably fixed after being wrapped with connective tissue.
[0020] The device of the present invention has a stable fixation: the traditional nail-piece system is a three-point fixation, a single titanium piece mode, while the present invention is a three-point or multi-point symmetrical fixation, each device will be fixed to the defective bone flap and the skull respectively for greater stability. They are respectively connected by the first titanium nail and the fixed titanium nail, and are stronger than the traditional fixation system.
[0021] The device of the present invention has an adjustable lifting function, which can effectively reduce brain damage caused by increased intracranial pressure after surgery, enhance postoperative rehabilitation effects, and reduce intracranial pressure.
[0022] The device of the present invention effectively reduces the empirical judgment of whether to keep or not the bone flap, provides a new option for the issue of whether to keep or not the bone flap for postoperative patients, and gives the surgeon more confidence in postoperative treatment. For patients with brain damage during surgery, the present invention can completely replace the traditional nail plate system for closing the skull, which can reduce postoperative complications, improve the surgeon's confidence, and reduce the difficulty of the surgeon's operation. It provides a new option and idea for most patients, between bone flap surgery and minimally invasive surgery, and has a very positive effect on the treatment of patients with brain damage.
[0023] The device of the present invention can perform skull repair in one stage. In surgery without infection risk, titanium mesh can be used to replace the one-stage skull repair, which not only reduces the risk of postoperative intracranial hypertension, but also reduces the risk and economic burden of secondary skull repair surgery. For patients with mild to moderate brain swelling after surgery, the device can be raised by about 6 mm, which can completely achieve the purpose of decompression. Especially for patients with moderate brain swelling, the bone flap with decompression effect plus traditional dehydration treatment can completely bring the best prognosis to patients without removing the bone flap, with faster recovery and better effect. For grassroots hospitals, for patients whose brain swelling is not obvious during surgery but who cannot determine the risk degree of postoperative brain swelling, the present invention can replace the traditional bone flap to ensure the surgical effect.
[0024] The present invention can also be applied to patients with mild symptoms, and can achieve the purpose of decompression at the earliest stage. For acute complications such as acute postoperative bleeding and drainage tube blockage, it can achieve the purpose of early decompression, buy time for a second operation, and improve the survival rate of patients.
[0025] The device of the present invention has a simple structure and controllable cost, and is conducive to practical application and promotion. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 The figure is a schematic diagram of the fixation of the device for fixation and reduction of the skull bone flap of the present invention.
[0027] Figure 2 The figure is a schematic diagram of the structure of the device for fixation and reduction of the skull bone flap of the present invention.
[0028] In the figure: 100-skull fixator, 101-side fixation end of skull, 102-first titanium nail, 103-lifting structure, 104-adjusting boss, 105-side fixation end of bone flap, 106-fixation titanium nail, 200-defective bone flap, 300-skull. DETAILED DESCRIPTION
[0029] In order to further understand the present invention, the present invention is described in detail below.
[0030] The present invention provides a device for fixing and reducing a skull bone flap, such as Figure 1 The device comprises a skull fixator 100 and a defective bone flap 200, wherein the skull fixator 100 is used to fix the defective bone flap 200 on the skull 300; the number of the skull fixators 100 is 3-6, preferably 3, and they are positioned and installed in a three-point (3-point) or multi-point symmetrical manner.
[0031] like Figure 2 As shown, the skull fixator 100 includes a skull side fixing end 101, a first titanium nail 102, a lifting structure 103, an adjusting boss 104, a bone flap side fixing end 105 and a fixing titanium nail 106; the skull side fixing end 101, the first titanium nail 102, the lifting structure 103, the adjusting boss 104, the bone flap side fixing end 105 and the fixing titanium nail 106 are all made of medical titanium alloy.
[0032] The skull side fixing end 101 is a semi-cylindrical structure with a radius of 5 mm, and a skull fixing hole is opened at its center; the bone flap side fixing end 105 is a scale-type structure, and an adjustment boss 104 is set at its center, and the adjustment boss 104 is a cylindrical structure with internal threads.
[0033] The lifting structure 103 is a spring made of medical stainless steel or titanium alloy, which is sleeved on the first titanium nail 102 and placed between the defective bone flap 200 and the adjustment boss.
[0034] The lower end of the skull side fixing end 101 is welded and fixed to the thick end of the bone flap side fixing end 105; preferably, the angle between the axis (height direction) of the skull side fixing end 101 and the length direction of the bone flap side fixing end 105 is 60-120°. The bottom surface of the adjusting boss 104 is welded and fixed to the bone flap side fixing end 105.
[0035] The skull side fixing end 101 is fixed on the skull 300 by fixing titanium nails 106. Specifically, the arc surface of the skull side fixing end faces the skull side, and a semi-cylindrical through groove adapted thereto is opened at a corresponding position of the skull. After the skull side fixing end is embedded in the semi-cylindrical through groove, the fixing titanium nails 106 pass through the skull fixing holes on the skull side fixing end 101, extend out of the skull side fixing end, and are fixed in the skull.
[0036] The bone flap side fixing end 105 is fixed to the defective bone flap 200 through the first titanium nail 102. Specifically, the first titanium nail 102 passes through the defective bone flap 200 and the lifting structure 103 in sequence and is screwed into the adjustment boss 104 to fix the defective bone flap 200 and the bone flap side fixing end 105 together.
[0037] The skull side fixing end 101 is preferably a semi-cylindrical structure with a radius of 5 mm.
[0038] The bone flap side fixing end 105 is preferably a scale-like structure with a length of 10 mm and a width of 8 mm.
[0039] The adjusting boss 104 preferably has an inner diameter of 3 mm, an outer diameter of 4 mm, and a height of 6 mm; the adjusting boss 104 preferably has a 6 mm limit to prevent the first titanium nail 102 from being tightened too hard or having too much rotational travel, which may cause adverse consequences such as damage to brain tissue.
[0040] The lifting structure 103 is preferably a spring with an inner diameter of 4.5 mm and a minimum compression length of 2 mm;
[0041] The cylindrical end radius of the first titanium nail 102 and the fixed titanium nail 106 is preferably 1.5 mm and the length is 8 mm; by adjusting the rotation of the first titanium nail 102, the lifting structure 103 is compressed to different degrees, so that the defective bone flap 200 is lifted or lowered; for example, the lifting structure 103 can lift the defective bone flap 200 by its elastic force by rotating the first titanium nail 102 clockwise; by rotating the first titanium nail 102 counterclockwise, the defective bone flap 200 is lowered by compressing the lifting structure 103, thereby reducing the distance between the defective bone flap 200 and the skull 300; the diameter of the first titanium nail 102 head should be larger than the diameter of the lifting structure 103; the maximum elastic force of the lifting structure 103 should be less than the maximum bearing capacity of the first titanium nail 102. The maximum lifting displacement is 6 mm, and the lowering displacement does not exceed the lowest point of the skull fixator 100.
[0042] When the present invention utilizes the device to fix and reduce the skull flap, three skull fixators are installed in a triangular position to fix the defective bone flap 200 on the skull 300. The device can also be dynamically adjusted according to the patient's physical condition. For example, when the wound is large, it is necessary to increase the number of skull fixators 100, such as selecting 4, 5 or 6 to meet the conditions of different patients; each skull fixator 100 is fixed to the defective bone flap and the skull respectively; then the first titanium nail is adjusted to rotate clockwise or counterclockwise to drive the defective bone flap to rise or fall, thereby adjusting the distance between the defective bone flap and the skull.
[0043] The device of the present invention provides a new means and method for the restoration and fixation of the bone flap after craniocerebral surgery, and provides a new choice between simple complete fixation and bone flap removal. The use of the fixation device for patients who may have increased intracranial pressure after surgery can effectively solve the problem of increased intracranial pressure after simple skull fixation, and help control the risk of postoperative brain tissue swelling in patients. At the same time, the device is stronger than the traditional nail plate fixation system and skull lock system, ensuring the stability of the bone flap after restoration. The device can achieve the lifting of the defective bone flap 200 by adjusting the first titanium nail 102, and can be restored normally according to the rotation path with a certain tension. A thinner titanium mesh can be used to replace the skull on the side of the bone flap. For patients who are not open and have no obvious infection, the purpose of primary repair of the skull after surgery is achieved. After 3 months after surgery, the connective tissue wrapping is no different from the existing skull fixation system on the market.
[0044] The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose is to enable technicians in this field to understand the content of the present invention and implement it. It cannot be used to limit the protection scope of the present invention. All equivalent changes or modifications made according to the essence of the present invention belong to the protection scope of the present invention.
Claims
1. A device for fixation and reduction of a skull flap, characterized in that: The device comprises a skull fixer (100) and a defective bone flap (200), wherein the skull fixer (100) is used to fix the defective bone flap (200) on the skull (300); The skull fixator (100) comprises a skull side fixation end (101), a first titanium nail (102), a lifting structure (103), an adjustment boss (104), a bone flap side fixation end (105) and a fixation titanium nail (106); The skull side fixing end (101) is fixedly connected to the bone flap side fixing end (105); the skull side fixing end (101) is fixed to the skull (300) by means of a fixing titanium nail (106); the adjusting boss (104) is arranged on the bone flap side fixing end (105), and the first titanium nail (102) passes through the defective bone flap (200) and the lifting structure (103) in sequence and is screwed together with the adjusting boss (104), so as to fix the defective bone flap (200) and the bone flap side fixing end (105) together.
2. The device for fixation and reduction of a skull flap according to claim 1, characterized in that: The skull side fixing end (101) is a semi-cylindrical structure with a radius of 5 mm, and a skull fixing hole is arranged at its center, and the fixing titanium nail (106) fixes the skull side fixing end (101) to the skull through the fixing hole; the arc surface of the skull side fixing end faces the skull side, and a semi-cylindrical through groove adapted to it is opened at a corresponding position of the skull, and the skull side fixing end is embedded in the through groove and fixed by the fixing titanium nail; the fixing titanium nail (106) extends out of the skull side fixing end and is fixed in the skull.
3. The device for fixation and reduction of a skull flap according to claim 1, characterized in that: The bone flap side fixing end (105) is a scale-like structure, and an adjustment boss (104) is arranged at its center. The adjustment boss (104) is a cylindrical structure with an internal thread. The first titanium nail (102) is screwed into the adjustment boss (104) to fix the bone flap side fixing end (105) and the defective bone flap together.
4. The device for fixation and reduction of a skull flap according to claim 3, characterized in that: The lifting structure (103) is a spring made of medical stainless steel or titanium alloy, which is sleeved on the first titanium nail (102) and placed between the defective bone flap (200) and the adjustment boss; the first titanium nail (102) passes through the defective bone flap (200) and the lifting structure (103) in sequence and is fixed on the adjustment boss (104).
5. The device for fixation and reduction of a skull flap according to claim 1, characterized in that: The number of the skull fixators (100) is 3-6, and they are positioned and installed in a three-point or multi-point symmetrical manner.
6. The device for fixation and reduction of a skull flap according to claim 1, characterized in that: The skull side fixing end (101) is a semi-cylindrical structure with a radius of 5 mm; the bone flap side fixing end (105) is a scaly structure with a length of 10 mm and a width of 8 mm; the inner diameter of the adjusting boss (104) is 3 mm, the outer diameter is 4 mm, and the height is 6 mm; the lifting structure (103) is a spring with an inner diameter of 4.5 mm and a minimum compression length of 2 mm; the adjusting boss (104) has a 6 mm limit to prevent the first titanium nail (102) from being tightened too much and the rotation stroke is too large, which may cause adverse consequences such as damage to brain tissue.
7. The device for fixation and reduction of a skull flap according to claim 6, characterized in that: The cylindrical ends of the first titanium nail (102) and the fixing titanium nail (106) have a radius of 1.5 mm and a length of 8 mm. By adjusting the rotation of the first titanium nail (102) to compress the lifting structure (103) to different degrees, the defective bone flap (200) can be lifted or lowered. The maximum lifting is 6 mm, and the lowering does not exceed the lowest point of the skull fixator (100).
8. The device for fixation and reduction of a skull bone flap according to claim 7, characterized in that: The lifting structure (103) can lift the defective bone flap (200) by rotating the first titanium nail (102) clockwise through its elastic force; by rotating the first titanium nail (102) counterclockwise, the defective bone flap (200) can be lowered by compressing the lifting structure (103), thereby reducing the distance between the defective bone flap (200) and the skull (300); the diameter of the nail head of the first titanium nail (102) should be larger than the diameter of the lifting structure (103); the maximum elastic force of the lifting structure (103) should be smaller than the maximum bearing capacity of the first titanium nail (102).
9. The device for fixation and reduction of a skull flap according to claim 5, characterized in that: The skull side fixing end (101), the first titanium nail (102), the lifting structure (103), the adjusting boss (104), the bone flap side fixing end (105) and the fixing titanium nail (106) are all made of medical titanium alloy.
10. A method for fixation and reduction of a skull bone flap using the device according to any one of claims 1 to 9, characterized in that: The method is to dynamically adjust the skull fixator (100) according to the patient's physical condition, and adopt three-point or multi-point symmetrical fixation to fix each skull fixator (100) to the defective bone flap and the skull respectively; then adjust the first titanium nail to rotate clockwise or counterclockwise to drive the defective bone flap to rise or fall, thereby adjusting the distance between the defective bone flap and the skull.