A controllable reduction decompression device under skull bone flap reservation

Abstract

The present application relates to a kind of controllable reduction decompression device under retaining skull bone flap, including at least two groups of skull fixation part and bone flap fixation part, the bone flap fixation part includes connecting plate and support plate, and the two inner walls of the support plate are equipped with support strip.The skull fixation part includes base, movable stop lever group and control mechanism.Control mechanism can be switched from initial support state to unlock state by movable stop lever group, when being in the unlock state, the maximum size of movable stop lever group two ends is less than the interval of the support strip, so that bone flap fixation part can be lowered.The present application is cooperated by support strip in bone flap fixation part and adjusting movable stop lever group in skull fixation part, the height of bone flap fixation part is controlled in initial support state, bone flap is lifted in situ after craniotomy is completed;When postoperative intracranial pressure returns to normal, operate control line, movable stop lever group is switched to unlock state to allow bone flap fixation part to be lowered, and bone flap is reset, and skull repair surgery can be completed without additional secondary craniotomy.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, and in particular relates to a controllable reduction and decompression device for preserving cranial bone flaps. Background Technology

[0002] Traumatic brain injury and stroke have devastating consequences and are among the major public health problems worldwide. For patients requiring cerebral decompression after traumatic brain injury or stroke, craniotomy is the most common surgical procedure. Patients with intracranial lesions requiring craniotomy may experience increased intracranial pressure due to cerebral edema or delayed hemorrhage, or the intracranial pressure may not be adequately reduced before skull closure, leading to risks associated with skull repositioning. In such cases, doctors usually opt for bone flap removal. However, the subsequent removal of the bone flap for decompression often results in bone flap loss, causing significant psychological distress and potentially leading to headaches, dizziness, and vibration-sensitive syndromes in patients. To restore the closure of the cranial cavity, maintain physiological intracranial pressure stability, and alleviate skull defect syndrome, cranioplasty is generally performed three months after craniotomy.

[0003] If the bone flap is removed during the first surgery and not preserved, the defect can only be repaired with other materials. This can lead to complications such as subcutaneous fluid accumulation, leakage of repair materials, seizures, infection, and flap necrosis, and even death during cranioplasty.

[0004] During the first surgery, because the intracranial pressure was not reduced, the bone flap could not be completely adhered to the skull and preserved. In order to ensure that the original bone flap could be used for cranioplasty, the following technical problems need to be solved: First, how to raise the bone flap to a sufficient height to ensure decompression space; Second, after the brain swelling subsides, an additional second surgery is still required to remove the device and reposition the original bone flap, which increases the patient's suffering. Excessive surgery also increases the medical burden on patients and the country.

[0005] The applicant's earlier patent application, CN215019748U, discloses a device for supporting and repositioning a cranial bone flap fixation. This device can suspend and fix the bone flap in situ after craniotomy, providing ample decompression space for the brain tissue. As an autologous subcutaneous implantation method for the bone flap, once the patient's intracranial pressure returns to normal 1-2 weeks post-surgery and the condition allows for bone flap repositioning, the flap can be repositioned simply by pulling a latch switch, completing the cranioplasty without additional alignment surgery. However, in practice, it has been found that the technical solution using a locking tooth segment and latch switch to connect the bone flap fixation part to the cranial fixation part suffers from drawbacks such as inflexible control and difficulty in unlocking. Summary of the Invention

[0006] The purpose of this invention is to provide a controllable reduction and decompression device for preserving cranial bone flaps, which solves the technical problems mentioned in the background art.

[0007] The technical solution adopted by the present invention to solve its technical problem is: to provide a controllable reduction and decompression device for preserving cranial bone flaps, including at least two sets of cranial fixation parts and bone flap fixation parts. The bone flap fixation part includes: a support plate: the support plate is arc-shaped in its initial state, and a guide groove is opened in the length direction inside. Several support strips are respectively provided on the two inner side walls of the guide groove. A bone flap connection structure for fixing and connecting with the bone flap is provided at one end of the support plate away from the opening of the guide groove; a gap channel: formed by the spacing of several pairs of symmetrically arranged support strips. The skull fixation part includes: a base with a skull connection structure at the bottom for fixed connection with the skull, and a guide hole thereon; a movable stop rod assembly: installed in the guide hole, the movable stop rod assembly can switch between an initial support state and an unlocked state, including at least three connecting rods, the connecting rods including two blocking rods and at least one operating rod; the blocking rods: the connecting ends of the two blocking rods are fixed in the guide hole, the two blocking rods can rotate relative to each other, when in the initial support state, the blocking rods form a shape that abuts against the support bar to restrict the position of the support plate in the guide hole; the operating rod: the end connected to the blocking rod is rotatable. The connecting part includes at least one weakening mechanism on the operating rod. When in the initial support state, both ends of the operating rod are locked in the guide hole, preventing the blocking rod from moving. The control mechanism includes a control line connected to the weakening mechanism. Pulling the control line can pull the operating rod away from the locked position through the weakening mechanism, thereby switching the movable stop rod group from the initial support state to the unlocked state. When in the unlocked state, the blocking rod loses the support of the operating rod, and its two ends can retract towards the center. After retraction, the maximum size of both ends of the operating rod is smaller than the minimum size of the gap channel, allowing the support plate to move along the length direction of the guide hole.

[0008] Preferably, when there is one operating lever, the movable stop lever group is connected to form an isosceles triangle, the length of the operating lever is the same as the inner cavity of the guide hole to achieve support, and the weakening mechanism is located in the middle of the operating lever.

[0009] Preferably, when the number of operating rods exceeds two, in the initial support state, the connecting ends of adjacent operating rods are aligned and maintain a coaxial relationship, the movable stop rod group is connected to form an isosceles triangle, and the several operating rods form an integral support with the same width as the inner cavity of the guide hole.

[0010] Preferably, the weakening mechanism is an extension arm located at one end of the operating lever, the extension arm having a pin rotatably connected to the adjacent connecting rod and a snap fastener for fixed connection to the adjacent connecting rod; or, the weakening mechanism is a breakable notch located in the middle of the operating lever.

[0011] Preferably, the connecting end of the blocking rod is rotatably connected by a connecting block. The connecting block is triangular and has a main pin and two secondary pins. The secondary pins are matched with pin holes located at the ends of the blocking rod, and the main pin is fixed in the pin fixing hole of the base.

[0012] Preferably, the skull connection structure includes a plurality of skull fixation holes formed on the base, and the base is fixed to the skull surface by titanium nails inserted into the skull fixation holes.

[0013] Preferably, the bone flap connection structure includes a plurality of bone flap fixation holes formed on the fixation plate, and the support plate is fixed to the surface of the bone flap by titanium nails passing through the bone flap fixation holes.

[0014] Preferably, the support bars are arranged in a fishbone pattern, with an angle of 30° to 90° with the sidewall of the guide groove.

[0015] Preferably, the connection end between the support bar and the guide groove is provided with a folding notch.

[0016] Preferably, adjacent connecting rods are connected by hinges or folding notches.

[0017] The beneficial effects are as follows: The present invention uses the fishbone-style support bars in the bone flap fixation part to cooperate with the adjustable stop bar group in the skull fixation part to control the height of the bone flap fixation part in the initial support state, so that the skull bone flap can be raised in situ after the craniotomy, giving the brain tissue sufficient decompression space and achieving the effect of bone flap decompression.

[0018] As an alternative to bone flap removal, once the patient's intracranial pressure returns to normal 1-3 weeks post-surgery and the condition allows for bone flap repositioning, the control line of the external scalp control mechanism can be manipulated to switch the movable stop group to the unlocked state, allowing the support plate to descend and the bone flap to be repositioned. This allows cranioplasty to be completed without the need for a second craniotomy.

[0019] In the initial support state, the movable stop bar assembly supports and restricts the movement of the support plate connecting the bone flap. It is unlocked by the control mechanism. In the unlocked state, the operating rod is folded. After folding, the stop bar closes accordingly and no longer supports the support bar, allowing the bone flap fixation part to be lowered. Attached Figure Description

[0020] Figure 1 A schematic diagram of a controllable reduction and decompression device for preserving cranial bone flaps in the state of bone flap elevation. Figure 2 A schematic diagram of a controlled reduction and decompression device for preserving cranial bone flaps in the state of bone flap elevation. Figure 3A schematic diagram of the bone flap repositioning state of a controllable repositioning and decompression device for preserving skull bone flaps. Figure 4 A schematic diagram of the bone flap repositioning state of a controllable repositioning and decompression device for preserving skull bone flaps. Figure 5 for Figure 1 Enlarged view of the fixation point of the middle bone flap; Figure 6 for Figure 1 Enlarged view of the fixation point of the middle skull; Figure 7 for Figure 5 Enlarged view of the movable stop lever assembly; Figure 8 for Figure 1 Cross-sectional view of the initial support state of the movable stop bar assembly; Figure 9 for Figure 1 Cross-sectional view of the unlocked position of the movable stop lever assembly.

[0021] Among them, 1-Bone flap fixation part; 101-Bone flap connection structure; 102-Support plate; 103-Support bar; 104-Gap channel; 105-Easily broken notch; 106-Guide groove; 107-Bone flap fixation hole; 2-Skull fixation part; 201-Base; 202-Modible stop bar assembly; 203-Blocking rod; 204-Operating rod; 205-Weakening mechanism; 206-Control line; 207-Guide hole; 208-Skull fixation hole; 209-Skull connection structure; 210-Main pin; 211-Pin fixation hole; 212-Secondary pin; 213-Connecting block; 3-Skull; 4-Bone flap.

[0022] The same markings in each diagram represent the same component. Detailed Implementation

[0023] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0024] This invention provides a controllable reduction and decompression device for preserving skull bone flaps. The device comprises two symmetrically arranged skull fixation parts 2 and matching bone flap fixation parts 1. It is used to elevate the autologous bone flap 4 during surgery to achieve decompression in patients with intracranial hypertension after craniocerebral trauma or cerebral hemorrhage. After surgery, the bone flap 4 can be repositioned in situ through the external traction control line 206 of the scalp, without the need for a second craniotomy.

[0025] The device consists of two main components: bone flap fixation part 1 and skull fixation part 2. Bone flap fixation part 1 is an auxiliary component. Figure 5 The arc-shaped support plate 102 structure shown has an initial curvature matching the physiological curvature of the human skull 3. A through-type guide groove 106 is formed along its length. Multiple sets of fishbone-shaped support strips 103 are symmetrically arranged on the inner walls of both sides of the guide groove 106. The angle between the support strips 103 and the side walls of the guide groove 106 is set to 45°. The gaps between each pair of symmetrical support strips 103 form a gap channel 104, serving as a passageway for the movable stop bar assembly 202 to retract and slide down after unlocking. An integrally formed bone flap 4 connecting structure 101 is formed at the end of the support plate 102 away from the opening of the guide groove 106. This structure has two bone flap 4 fixation holes 107. During surgery, medical titanium screws are passed through the bone flap 4 fixation holes 107 to rigidly lock the support plate 102 onto the upper surface of the free autologous bone flap 4, achieving a stable connection between the bone flap 4 and the bone flap fixation part 1.

[0026] The main body of the skull fixation part 2 is an attachment Figure 6 The integrated base 201 shown has two wings forming a skull 3 connecting structure 209. The wings have skull 3 fixing holes 208. Titanium nails can be inserted into the skull 3 fixing holes 208 to anchor the base 201 flatly to the intact skull 3 surface around the craniotomy incision. A guide hole 207 is opened laterally in the center of the base 201. The width of the guide hole 207 is adapted to the overall lateral length of the operating rod 204 in the initial support state. Pin fixing holes 211 are reserved in the center of the top and bottom surfaces of the base 201 for assembling triangular connecting blocks 213. The triangular connecting block 213 is a triangular component with a main pin 210 at one of its upper corners. The main pin 210 is inserted into the pin fixing hole 211 to achieve hinged positioning. The remaining two corners of the connecting block 213 are each provided with a secondary pin 212. One end of each of the two blocking rods 203 is pinned to the secondary pin 212. The two blocking rods 203 can be opened outward and closed inward synchronously around the secondary pin 212.

[0027] The movable stop lever assembly 202 is installed inside the guide hole 207 of the base 201. The movable stop lever assembly 202 is shown in the attached figure. Figure 7 The diagram shows two blocking rods 203 and an operating rod 204, which are hinged to form an isosceles triangular support frame. In this embodiment, the operating rod 204 is a single integrated rod, but in other embodiments, multiple segments can be spliced ​​together. When a single operating rod 204 is selected, the overall length of the operating rod 204 is the same as the inner width of the guide groove 106 of the support plate 102, and a weakening mechanism 205 is set in the middle. When two segmented operating rods 204 are selected, in the initial support state, the joint ends of the two segments of the operating rod 204 are closely fitted to each other and keep in the same straight line. After splicing, the overall width matches the guide hole 207, which also forms an isosceles triangular support structure.

[0028] The weakening mechanism 205 has several optional structures. In this embodiment, it is an easy-break notch 105 opened in the middle of the operating rod 204. The depth of the notch is half the thickness of the rod body. The force is concentrated at the notch, and it breaks directly under the pull force to complete the unlocking. Another embodiment is an extension arm extending from the end of the operating rod 204. The extension arm is equipped with a rotating pin and a fixed snap. In the initial state, the snap locks the two sections of the operating rod 204 to maintain straight support. After pulling the control line 206 to disengage the snap, the two sections of the operating rod 204 fold inward with the pin as the fulcrum. Both weakening mechanisms 205 are connected to the control line 206 of the control mechanism. One end of the control line 206 is fixed at the position of the weakening mechanism 205, and the other end extends along the outside of the guide hole 207 and is buried under the scalp. Only a small traction suture head is reserved. After the operation, only local anesthesia is required for external operation. Two connection methods can be selected between adjacent links. One is a micro-hinge connection, which is smooth to rotate and has stable support strength, and is the preferred structure in this embodiment. The other is to open an easy-break notch 105 at the joint end of the link. In the initial state, the notch maintains rigid support, and after being pulled and stressed, it is easy to undergo plastic deformation to realize the link closing. This can simplify the processing technology and is suitable for mass production at low cost.

[0029] The procedure for using this invention is as follows: After craniotomy to remove intracranial lesions and hematomas, two sets of skull fixation parts 2 are fixed to the skull bones 3 on both sides of the bone flap 4. The base 201 is anchored in place with titanium nails, ensuring that the movable stop bar group 202 in the guide hole 207 of the base 201 is in the initial support state. The stop bar 203 is pushed outward, and its top end abuts against the bottom of the paired support bars 103 at the same height. The support plate 102 is supported by the triangular support structure. Then, the corresponding support bar 103 of the bone flap fixation part 1 is selected according to the required height, and the support bar 103 below it is broken and rendered ineffective. The support plate 102 of the bone flap fixation part 1 is inserted into the guide hole 207 of the base 201. The two side support plates 102 are sleeved on the outside of the movable stop bar group 202. At this time, the two ends of the operating rod 204 abut against the inner wall of the guide groove 106, and the two stop bars 203 are locked laterally. Finally, the top end of the support plate 102 is fixed to the autologous bone flap 4 with titanium nails. After fixation, the overall state is as follows. Figure 2 , 8 As shown, bone flap 4 is raised by 10-15mm, forming a closed decompression cavity above the brain tissue, eliminating the need to discard autologous bone flap 4 and replacing the traditional bone flap 4 removal surgery.

[0030] After a 1-3 week post-operative wait, a follow-up cranial CT scan confirms the reduction of cerebral edema and the return of intracranial pressure to normal levels. Local anesthesia is then administered to the scalp at the location of the pre-embedded control line 206. The control line 206 is pulled outwards. If it is a weakening mechanism 205, the pulling force will cause the operating rod 204 to break from the middle. If it is an extension arm snap-on structure, the snap will disengage, and the segmented operating rod 204 will fold inwards. After the operating rod 204 loses its lateral limiting support, the two blocking rods 203 are no longer constrained and synchronously retract towards the center around the secondary pin 212. After retraction, the maximum lateral dimension at both ends of the movable stop rod assembly 202 is less than the minimum width of the gap channel 104. The support plate 102 loses its upward lifting force and can slide downwards along the length of the guide hole 207. The entire device is then switched to... Figure 4 , 9 As shown in the reset state, bone flap 4 falls back with support plate 102 and fits the wound surface of skull 3, completing the in-situ repair of autologous bone flap 4. The entire process does not require cutting the scalp again or performing a second craniotomy to remove the device. It can effectively avoid complications such as subcutaneous fluid accumulation, infection, epilepsy, and flap necrosis caused by allogeneic repair materials, while eliminating problems such as headache, dizziness, and psychological anxiety caused by skull 3 defect syndrome.

[0031] In this application, the bone flap fixation part 1 and the skull fixation part 2 can be made of absorbable materials (such as magnesium alloy or poly-L-lactic acid). The advantages are that no secondary surgery is needed to remove the implant after surgery, reducing the risk of trauma and infection; the material can be gradually degraded, avoiding the discomfort caused by long-term metal retention in the body and the artifacts on head MRI; it is suitable for young patients and avoids the drawbacks of permanent metal implantation. Alternatively, non-absorbable materials (such as titanium alloy) can be used. The advantages are stable mechanical strength, reliable support of the bone flap 4 throughout the procedure, no risk of degradation or failure; mature biocompatibility, resistance to intracranial fluid corrosion, suitable for long-term intracranial retention; high processing precision, stable dimensions of the support strip 103 and the baffle structure, and strong controllability of surgical operation. The selected material should ensure that the support plate 102 and the connection between the support plate 102 and the bone flap connection structure 101 can withstand pressure deformation.

[0032] This embodiment solves the shortcomings of existing similar devices, such as inflexible height adjustment and laborious unlocking operation, by using a fishbone-type multi-level support bar 103 in combination with a triangular structure movable stop bar group 202. Intracranial decompression and long-term skull repair can be completed simultaneously in a single craniotomy, which not only reduces the pain caused by multiple surgeries for patients, but also reduces the overall burden of medical consumables and surgical treatment, and has good clinical application prospects.

Claims

1. A controllable reduction and decompression device for preserving a cranial flap, comprising at least two sets of cranial fixation parts and a flap fixation part, characterized in that, The bone flap fixation unit includes: Support plate: The support plate is arc-shaped in its initial state and has a guide groove opened along its length inside. Several support strips are provided on the two inner side walls of the guide groove. The end of the support plate away from the opening of the guide groove is provided with a bone flap connection structure for fixed connection with the bone flap. Gap channel: formed by the spacing of several pairs of symmetrically arranged support bars. The skull fixation component includes: The base has a skull connection structure at the bottom for fixed connection with the skull, and a guide hole is provided on it; Movable stop lever assembly: Installed in the guide hole, the movable stop lever assembly can switch between the initial support state and the unlocked state, and includes at least three connecting rods, the connecting rods including two blocking rods and at least one operating rod; The blocking rod: the connecting ends of the two blocking rods are fixed in the guide hole, and the two blocking rods can rotate relative to each other. When in the initial support state, the blocking rod forms a shape that abuts against the support bar to restrict the position of the support plate in the guide hole. The operating lever: the end connected to the blocking rod is a rotating connection part, and the operating lever is provided with at least one weakening mechanism. When in the initial support state, both ends of the operating lever are stuck in the guide hole so that the blocking rod cannot move. Control mechanism: includes a control line connected to the weakening mechanism. Pulling the control line can pull the operating lever from its locked position through the weakening mechanism, thereby switching the movable stop lever group from the initial supported state to the unlocked state. When in the unlocked state, the stop lever loses the support of the operating lever, and its two ends can retract towards the center. After retraction, the maximum size of the two ends of the operating lever is smaller than the minimum size of the gap channel, allowing the support plate to move along the length direction of the guide hole.

2. The controllable reduction and decompression device under skull flap preservation according to claim 1, characterized in that, When there is only one operating lever, the movable stop lever group is connected to form an isosceles triangle. The length of the operating lever is the same as the inner cavity of the guide hole to provide support. The weakening mechanism is located in the middle of the operating lever.

3. The controllable reduction and decompression device under skull flap preservation according to claim 1, characterized in that, When there are more than two operating rods, in the initial support state, the connecting ends of adjacent operating rods are aligned and maintain a straight line relationship. The movable stop rod group is connected to form an isosceles triangle, and several operating rods form an integral support with the same width as the inner cavity of the guide hole.

4. A controllable reduction and decompression device for preserving a skull flap as described in claim 2 or 3, characterized in that, The weakening mechanism is an extension arm located at one end of the operating lever. The extension arm is provided with a pin that can be rotatably connected to the adjacent connecting rod and a snap fastener for fixing the adjacent connecting rod. Alternatively, the weakening mechanism is a breakable notch located in the middle of the operating lever.

5. The controllable reduction and decompression device under cranial flap preservation according to claim 1, characterized in that, The connecting ends of the blocking rod are rotatably connected by a connecting block. The connecting block is triangular and has a main pin and two secondary pins. The secondary pins are matched with pin holes located at the ends of the blocking rod, and the main pin is fixed in the pin fixing hole of the base.

6. The controllable reduction and decompression device under cranial flap preservation according to claim 1, characterized in that, The skull connection structure includes a plurality of skull fixation holes formed on the base, and the base is fixed to the skull surface by titanium nails inserted into the skull fixation holes.

7. The controllable reduction and decompression device under cranial flap preservation according to claim 1, characterized in that, The bone flap connection structure includes a plurality of bone flap fixation holes formed on the fixation plate, and the support plate is fixed to the surface of the bone flap by titanium nails passing through the bone flap fixation holes.

8. The controllable reduction and decompression device under cranial flap preservation according to claim 1, characterized in that, The support bars are arranged in a fishbone pattern, with an angle of 30° to 90° with the sidewall of the guide groove.

9. A controllable reduction and decompression device for preserving cranial bone flaps according to claim 1, characterized in that, The connection end between the support bar and the guide groove is provided with a folding notch.

10. A controllable reduction and decompression device for preserving a skull flap according to claim 1, characterized in that, The adjacent links are connected by hinges or folding notches.

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