A dynamic dislocation prevention system for a pediatric acetabular prosthesis
By using dynamic anti-dislocation components and angle adjustment devices in pediatric acetabular prostheses, the problems of prosthesis dislocation and epiphyseal damage caused by children's bone growth are solved, achieving prosthesis stability and synchronous extension, and avoiding the defects of traditional devices.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-10
- Publication Date
- 2026-03-24
AI Technical Summary
The unique biological characteristics of children's bone growth lead to a pathological increase in the acetabular anteversion angle and longitudinal growth, increasing the risk of dislocation of the hemi-hip prosthesis ball head assembly. Traditional rigid fixation devices cannot adapt to the dynamic development of bones, resulting in epiphyseal damage and loosening of the prosthesis-bone interface.
It adopts a dynamic anti-dislocation component, including an anti-dislocation baffle, a gear mechanism and an angle adjustment device. The three-dimensional structure fills the outer edge of the acetabulum, and the anti-dislocation baffle is extended synchronously by mechanical transmission to adapt to bone growth and avoid prosthesis dislocation and epiphyseal damage.
It effectively prevents non-physiological displacement of the hemi-hip prosthesis ball head assembly, avoids growth inhibition and secondary surgery, improves the stability and long-term mechanical reliability of the prosthesis, and overcomes the defects of traditional devices.
Smart Images
Figure CN120732585B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of children's orthopedic implant devices, in particular to a dynamic anti-dislocation system for children's acetabular prosthesis. BACKGROUND
[0002] With the significant progress of limb-salvage treatment for children's malignant bone tumors (such as osteosarcoma and Ewing's sarcoma), tumor-type hemi-hip arthroplasty has become an important surgical treatment. However, the special biological characteristics of children's skeletal system pose unique challenges to the design of the prosthesis: on the one hand, clinical studies have shown that about 35% of children with bone tumors have pathological increase in the acetabular anteversion angle (> 25°) due to abnormal bone development (such as acetabular dysplasia) or aggressive tumor growth, which can significantly increase the dynamic instability of the hemi-hip prosthesis ball head assembly in the outer edge area of the acetabulum, and further lead to the risk of non-physiological subluxation or even complete dislocation; on the other hand, children's bones grow rapidly (5-8 cm in height per year), and traditional rigid fixation devices cannot be extended with bone growth, resulting in biomechanical mismatch, which may cause iatrogenic damage to the epiphyseal growth plate and mechanical loosening of the prosthesis-bone interface, ultimately leading to failure of the prosthesis. SUMMARY
[0003] To solve the technical problems of the prior art, such as the increased risk of dislocation of the hemi-hip prosthesis ball head assembly due to the special biological characteristics of children's skeletal growth (such as pathological increase in the acetabular anteversion angle and continuous longitudinal growth), and mechanical failure such as damage to the epiphyseal growth plate and loosening of the prosthesis-bone interface caused by the inability of traditional rigid fixation devices to adapt to the dynamic development of the skeleton, the present application provides a dynamic anti-dislocation system for children's acetabular prosthesis. The technical solution is as follows:
[0004] The present application provides a dynamic anti-dislocation system for children's acetabular prosthesis, comprising:
[0005] The dynamic anti-dislocation assembly comprises a fixing member;
[0006] The gear mechanism comprises a gear and a transmission rack; two fixing members are arranged on both sides of the gear; the two fixing members are connected to the gear through the transmission rack; and the gear is driven to rotate by the fixing members;
[0007] The anti-dislocation baffle is a telescopic arc-shaped baffle; the two ends of the anti-dislocation baffle are installed at the outer edge of the acetabulum through the fixing members; and the anti-dislocation baffle is used to block the dislocation of the hemi-hip prosthesis ball head assembly from the acetabulum.
[0008] Optionally, the dynamic anti-dislocation assembly further comprises a housing;
[0009] The shell is provided with an inner cavity and a movable hole, the inner cavity is communicated with the movable hole; the gear is rotatably installed in the inner cavity; one end of the transmission rack is connected with the corresponding fixed part, and the other end of the transmission rack is extended into the inner cavity through the movable hole and is meshingly connected with the gear.
[0010] Optionally, further comprising: a ratchet mechanism; the ratchet mechanism comprises:
[0011] A ratchet wheel is coaxially fixedly connected with the gear;
[0012] A check pawl is rotatably installed at the fulcrum end in the inner cavity; the check pawl has a locking and limiting state of abutting against the ratchet teeth of the ratchet wheel, and a disengaging state of being separated from the ratchet teeth of the ratchet wheel under the action of an external force.
[0013] Optionally, a limiting part is arranged on the side of the check pawl, and the limiting part limits the swing of the check pawl.
[0014] Optionally, the dynamic anti-disengagement system of the child's acetabular prosthesis further comprises: an angle adjusting device; both ends of the anti-disengagement baffle are installed on the corresponding fixed parts through the angle adjusting device; the angle adjusting device comprises:
[0015] A worm wheel comprises: a toothed part and a rim part; the fixed part has a cavity inside, the toothed part is rotatably arranged in the cavity, and the rim part is extended out of the cavity and connected with the anti-disengagement baffle;
[0016] A worm is further arranged on the fixed part and inserted into the insertion hole and meshingly connected with the toothed part of the worm wheel, the worm drives the worm wheel to rotate the anti-disengagement baffle at the outer edge of the acetabulum;
[0017] A rotating shaft is connected with the worm wheel at one end and rotatably connected with the shell at the other end, and the rotating shaft rotates with the worm wheel.
[0018] Optionally, the angle adjusting device further comprises:
[0019] A knob is arranged at the end of the worm, the knob drives the worm to rotate the worm wheel; a plurality of clamping grooves are arranged on the knob in the circumferential direction;
[0020] A limiting pin is further arranged on the fixed part, one end of the limiting pin is matched and inserted into the limiting hole, and the other end of the limiting pin is clamped with the clamping groove.
[0021] Optionally, the angle adjusting device further comprises: a support assembly; the support assembly comprises:
[0022] A support rod having a first end and a second end; the first end is hinged to the anti-detachment baffle.
[0023] The slide rail is mounted on the fixing member along the direction perpendicular to the axis of the worm gear;
[0024] A sliding element is provided, wherein the second end of the support rod is slidably connected to the slide rail via the sliding element.
[0025] Optionally, the sliding member includes: a sliding rod and a connecting member; both ends of the sliding rod are respectively fixed to the second end of the support rod through the connecting member; the slide rail is provided with a movable through hole that cooperates with the sliding rod to slide.
[0026] Optionally, the anti-detachment baffle includes:
[0027] The telescopic section includes two stacked side wing plates;
[0028] Two arc-shaped baffles are respectively disposed on both sides of the telescopic part; the straight edge of each arc-shaped baffle is connected to a side wing plate, and the convex arc surface of the arc-shaped baffle is connected to the corresponding fixing member.
[0029] Optionally, the anti-detachment baffle has a smooth coating on its surface.
[0030] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following:
[0031] This invention provides a dynamic anti-dislocation system for pediatric acetabular prostheses. An anti-dislocation baffle is installed at the outer edge of the acetabulum. A three-dimensional structure is used to fill and reconstruct the continuity of the acetabular outer edge, establishing a mechanical barrier to prevent non-physiological displacement of the hemiarthroplasty ball head assembly and its dislocation from the acetabulum. Simultaneously, a dynamic growth fixation device, consisting of bilateral fixation members, a reverse transmission rack and pinion mechanism, is used to fix the anti-dislocation baffle. Mechanical transmission converts the longitudinal growth force of the bone into biomimetic extension movement, achieving synchronous extension with the child's bone growth. This avoids growth inhibition and the need for secondary surgery, and overcomes problems such as epiphyseal damage and prosthesis loosening caused by traditional rigid fixation devices. Attached Figure Description
[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0033] Figure 1 This is a three-dimensional morphological image of a pathological acetabulum in a child;
[0034] Figure 2This is a schematic diagram of the installation of a dynamic anti-dislocation system for pediatric acetabular prostheses according to an embodiment of the present invention;
[0035] Figure 3 This is a schematic diagram of the initial state structure of the dynamic anti-dislocation system for pediatric acetabular prostheses provided by some embodiments of the present invention;
[0036] Figure 4 This is a schematic diagram of the initial state structure of a dynamic anti-dislocation system for pediatric acetabular prostheses according to other embodiments of the present invention;
[0037] Figure 5 This is a schematic diagram of the extended state structure of the dynamic anti-dislocation system for pediatric acetabular prostheses provided by some embodiments of the present invention;
[0038] Figure 6 This is a schematic diagram of the angle adjustment device provided in some embodiments of the present invention.
[0039] Figure label:
[0040] Dynamic anti-detachment component 1; fastener 11; cavity 111; shell 12; inner cavity 121;
[0041] Gear mechanism 2: Gear 21; Transmission rack 22; Axial stop 23; Stop pin 24;
[0042] Anti-detachment baffle 3; side wing plate 31; arc baffle 32;
[0043] Ratchet mechanism 4; Ratchet 41; Check pawl 42; Pawl 421; Spring 422; Limiting element 43;
[0044] Angle adjustment device 5; worm gear 51; gear tooth 511; rim 512; worm 52; rotating shaft 53; knob 54; slot 541; limit pin 55; support assembly 56; support rod 561; slide rail 562; movable through hole 5621; sliding component 563;
[0045] 100mm outer edge of acetabulum; 200mm ball head assembly of hemi-hip prosthesis. Detailed Implementation
[0046] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.
[0047] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms “first,” “second,” and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an,” “a,” or “the,” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “comprising,” “including,” or “including,” and similar terms mean that the element or object preceding the word encompasses the element or object listed following the word and its equivalents, without excluding other elements or objects. The terms “connected,” “linked,” or “connected,” and similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.
[0048] It should be noted that the terms "up", "down", "left", "right", "front" and "back" used in this invention are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.
[0049] Due to the unique biological characteristics of children's bone growth, on the one hand, the acetabular anteversion angle may pathologically increase, significantly increasing the risk of dislocation of the hemi-hip prosthesis ball head assembly 200 in the acetabular outer edge 100 region; on the other hand, traditional rigid fixation devices cannot adapt to the dynamic development of bones, leading to mechanical failures such as epiphyseal loosening and prosthesis-bone interface loosening.
[0050] The acetabular anteversion angle refers to the angle of inclination of the acetabulum in the horizontal plane. Its normal range is usually 15-20°. However, children with bone tumors may have an increased acetabular anteversion angle due to abnormal bone development or invasive tumor growth. Figure 1 It is a three-dimensional morphological image of a pathological acetabulum in a child, such as Figure 1 As shown, pathological hip acetabular development in children presents with typical morphological abnormalities, with multiple areas of high tilt angle (>25°) at 100° of the acetabular rim. Under this structure, the ball joint assembly of the hemi-hip prosthesis is prone to non-physiological displacement or slippage along the high tilt surface due to insufficient mechanical stability.
[0051] Figure 2 This is a schematic diagram of the installation of a dynamic anti-dislocation system for pediatric acetabular prostheses according to an embodiment of the present invention, as shown below. Figure 2As shown, to address the aforementioned problems, this invention proposes a dynamic anti-dislocation system for pediatric acetabular prostheses. By adding an adaptive anti-dislocation baffle structure to the high tilt angle region, it morphologically compensates for the 100° bony defect at the outer edge of the acetabulum, reducing the effective local tilt angle. A physical anti-dislocation barrier is constructed using a three-dimensional curved baffle to limit abnormal displacement of the acetabular head. To achieve stable fixation of the anti-dislocation baffle at the outer edge of the acetabulum at 100°, while adapting to the biomechanical characteristics of children's bone growth and development, this invention adopts a biomimetic extension mechanism, using a dynamic growth-adaptive fixation system to replace the traditional rigid fixation device, extending synchronously with the longitudinal growth of the bone.
[0052] Figure 3 This is a schematic diagram of the initial state structure of the dynamic anti-dislocation system for pediatric acetabular prostheses provided by some embodiments of the present invention; Figure 4 This is a schematic diagram of the initial state structure of a dynamic anti-dislocation system for pediatric acetabular prostheses according to other embodiments of the present invention; Figure 5 This is a schematic diagram of the extended state structure of the dynamic anti-dislocation system for pediatric acetabular prostheses provided by some embodiments of the present invention. (See also...) Figures 3-5 This invention provides a dynamic anti-dislocation system for pediatric acetabular prostheses, comprising: a dynamic anti-dislocation component 1, a gear mechanism 2, and an anti-dislocation baffle 3. The dynamic anti-dislocation component 1 includes: a fixing member 11; the gear mechanism 2 includes: a gear 21 and a transmission rack 22; the two fixing members 11 are disposed on both sides of the gear 21 and are respectively connected to the gear 21 through the transmission rack 22, and the gear 21 rotates under the drive of the fixing members 11; the anti-dislocation baffle 3 is a retractable arc-shaped baffle, with both ends respectively installed at the outer edge 100 of the acetabulum through the fixing members 11, and the anti-dislocation baffle 3 is used to block the hemi-hip prosthesis ball head assembly 200 to prevent dislocation from the acetabulum.
[0053] The fixing member 11 is used to fix the anti-dislodgement baffle 3 at the outer edge 100 of the acetabulum. The meshing of the gear 21 and the transmission rack 22 allows the fixing members 11 on both sides of the gear 21 to extend synchronously with the longitudinal growth of the bone. For example, Figure 4 As shown, the transmission rack 22, connected to the fixation member 11 on the left side of gear 21, is located above gear 21 and meshes with the teeth at the top of gear 21; while the transmission gear 13, connected to the fixation member 11 on the right side of gear 21, is located below ratchet 21 and meshes with the teeth at the bottom of gear 21. The separation force generated by the longitudinal growth of the bone drives the fixation members 11 on both sides to move away from each other, and the upper and lower transmission racks 22, driven by the fixation members 11, cause gear 21 to rotate counterclockwise through reverse synchronous drive. It should be noted that the fixation member 11 can be fixedly installed on the bone at the outer edge 100 of the acetabulum using bone screws or other components.
[0054] The two ends of the anti-detachment baffle 3 are connected to the two-sided fixing members 11 respectively. The two-sided fixing members 11 extend longitudinally under the drive of bone growth, which will cause the two ends of the anti-detachment baffle 3 to stretch. Therefore, the anti-detachment baffle 3 needs to adopt a dynamic telescopic structure design at the same time. The dynamic telescopic function can be achieved by using an elastomer, telescopic mechanism or separable parts.
[0055] The anti-dislocation baffle 3 can be designed with arc-shaped ends, and its radius of curvature is consistent with the outer edge of the acetabular fossa. Through biomimetic morphological reconstruction, the outer edge of the acetabulum is filled and reconstructed with a 100° continuity using a three-dimensional structure to establish a mechanical barrier to prevent non-physiological displacement.
[0056] Specifically, see Figure 4 In some embodiments, the anti-detachment baffle 3 may specifically include: a telescopic part and two arc-shaped baffles 32; the telescopic part includes two stacked side wing plates 31; the two arc-shaped baffles 32 are respectively disposed on both sides of the telescopic part; the straight edge of each arc-shaped baffle 32 is connected to a side wing plate 31, and its convex arc surface is connected to the corresponding fixing member 11.
[0057] To reduce the interfacial frictional resistance between the anti-detachment baffle 3 and the surrounding tissue, a smooth coating can be applied to the surface of the anti-detachment baffle 3. The smooth coating can be made of zirconia ceramic material and applied to the surface of the anti-detachment baffle 3 by plasma spraying technology. The zirconia ceramic surface has an extremely low coefficient of friction and excellent wear resistance, which can effectively reduce the friction between the anti-detachment baffle 3 and the surrounding tissue, and significantly improve the long-term biocompatibility of the implant-tissue.
[0058] Furthermore, a porous ingrowth-promoting coating can be applied to the surface of the bone screws used for fixing the fixation component 11 or the surface of the hemi-hip prosthesis ball head assembly 200. This porous ingrowth-promoting coating is made of porous titanium alloy material and is formed uniformly on the prosthesis surface using a 3D printing laser sintering method. The porous titanium alloy material promotes bone ingrowth, facilitating osteoblast adhesion, proliferation, and differentiation on its surface. This guides bone tissue to gradually grow into the pores of the coating, forming a strong bone-prosthesis bond and improving the long-term stability of the prosthesis.
[0059] This invention provides a dynamic anti-dislocation system for pediatric acetabular prostheses. By setting an anti-dislocation baffle 3 at the outer edge 100 of the acetabulum, the continuity of the outer edge 100 of the acetabulum is reconstructed using a three-dimensional structure to establish a mechanical barrier to prevent the hemiarthroplasty ball head assembly 200 from dislocating from the acetabulum due to non-physiological displacement. At the same time, a dynamic growth fixation device consisting of bilateral fixation members 11, a reverse transmission rack 22, and a gear 21 is used to fix the anti-dislocation baffle 3. The longitudinal growth force of the bone is converted into biomimetic extension movement through mechanical transmission, so as to achieve synchronous extension with the growth of the child's bones, avoid growth inhibition and secondary surgery, and overcome the problems of epiphyseal damage and prosthesis loosening caused by traditional rigid fixation devices.
[0060] Further reading Figure 4 The dynamic anti-detachment component 1 also includes: a housing 12; the housing 12 has an inner cavity 121 and a movable hole communicating with the inner cavity 121; a gear 21 is rotatably installed in the inner cavity 121; one end of the transmission rack 22 is connected to the corresponding fixing member 11, and the other end extends into the inner cavity 121 through the movable hole and meshes with the gear teeth of the gear 21.
[0061] It should be noted that a fixed shaft is vertically installed on the inner wall of the housing 12, and the gear 21 is installed through a bushing. To ensure the reliability of gear meshing during reverse transmission, an axial stop 23 is provided at the end of the transmission rack 22 away from the fixed part 11, and a stop pin 24 is installed at the corresponding position on the side wall of the housing 12, forming a mechanical limiting pair. The stop-stop pin cooperation constitutes a bidirectional displacement limiting structure, so that the transmission rack 22 always maintains meshing with the gear teeth during dynamic movement.
[0062] The housing 12 serves as the core support structure, providing fixation and support for the gear mechanism 2 and the dynamic anti-detachment component 1, and optimizing the stress transmission path, making the entire dynamic anti-detachment system more stable and reliable, and improving the long-term mechanical reliability of the system during the child's bone growth process.
[0063] To ensure that the two-sided fixing members 11 maintain a stable mechanical position after dynamic extension and to prevent them from retracting after extension, a one-way motion lock needs to be implemented on the gear mechanism 2. (See reference...) Figure 4 In some embodiments, the dynamic anti-detachment system further includes a ratchet mechanism 4; the ratchet mechanism 4 includes a ratchet 41 and a check pawl 42; the ratchet 41 is coaxially and fixedly connected to the gear 21; the fulcrum end of the check pawl 42 is rotatably installed in the inner cavity 121; the check pawl 42 has a locking and limiting state that abuts against the ratchet teeth of the ratchet 41, and a disengaged state that is disengaged from the ratchet teeth of the ratchet 41 when it is moved by an external force.
[0064] The check pawl 42 consists of a pawl 421 and a spring 422. The ratchet 41 has ratchet teeth, which are unidirectional. The fulcrum end of the pawl 421 is oscillatingly mounted in the inner cavity 121, and the oscillating end of the pawl 421 is elastically connected to the housing 12 via the spring 422, and abuts against the ratchet teeth under the drive of the spring 422 to lock the ratchet 21.
[0065] Understandably, the asymmetrical tooth profile design of the unidirectional teeth allows the ratchet 41 to rotate only counterclockwise, preventing clockwise retraction. The pawl 421 has a fulcrum end and a swing end. The fulcrum end can be mounted on the side wall of the inner cavity 121 of the housing 12 via a fixed shaft-shoulder structure. The swing end, under the preload of the spring 422, remains locked against the tooth groove of the ratchet. The direction of the force of the spring 422 is consistent with the tangential direction of the counterclockwise rotation of the ratchet 41, ensuring that the pawl 421 always applies a counterclockwise rotational force to the ratchet 41, thus preventing the ratchet 41 from rotating clockwise and retracting, maintaining a self-locking state. The unidirectional locking structure of the ratchet mechanism 4 not only allows for adaptive adjustment and extension during the child's bone growth period but also maintains a locked state when bone growth stops, ensuring the structural stability of the hemi-hip prosthesis and preventing displacement under load.
[0066] To enhance the anti-reverse reliability of the ratchet mechanism 4, a limiting element 43 is provided on the periphery of the check pawl 42 to restrict the swing of the check pawl 42. When the system is subjected to an abnormal clockwise torque, the check pawl 42 will deflect slightly until the limiting element 43 contacts the stop surface, thereby achieving secondary locking.
[0067] Furthermore, Figure 6 These are schematic diagrams of the angle adjustment device according to some embodiments of the present invention. (See attached diagram.) Figure 6 In some embodiments, the anti-detachment system further includes an angle adjustment device 5; both ends of the anti-detachment baffle 3 are respectively mounted on corresponding fasteners 11 via the angle adjustment device 5. The anti-detachment baffle 3 can be angled by the angle adjustment device 5, enabling anteversion angle compensation during surgery.
[0068] During the surgery, the surgeon can precisely adjust the angle of the anti-dislocation baffle 3 according to the patient's specific acetabular shape and anteversion angle, and then lock it in the appropriate position to provide additional protection for the prosthesis, effectively preventing superior and posterior dislocation. The anteversion angle compensates for abnormal acetabular shape, disperses stress, and reduces the risk of dislocation.
[0069] Specifically, see Figure 6 In some embodiments, the angle adjustment device 5 includes: a worm gear 51, a worm 52, and a rotating shaft 53; the worm gear 51 includes: a toothed portion 511 and a rim portion 512; the fixing member 11 has a cavity 111 inside, the toothed portion 511 is rotatably disposed in the cavity 111, and the rim portion 512 extends out of the cavity 111 and is connected to the anti-dislodgement baffle 3; one end of the rotating shaft 53 is connected to the worm gear 51, and the other end is rotatably connected to the housing 12 and rotates with the worm gear 51; the fixing member 11 is also provided with an insertion hole communicating with the cavity 111, the worm 52 is inserted into the insertion hole and meshes with the toothed portion 511 of the worm gear 51, and the worm 52 drives the worm gear 51 to drive the anti-dislodgement baffle 3 to rotate at the outer edge 100 of the acetabulum.
[0070] The portion of the worm gear 51 located inside the cavity 111 has teeth, i.e., the toothed portion 511, while the portion extending outside the cavity 111 has no teeth, i.e., the rim portion 512. The worm gear 51 rotates in opposite directions around the extensions of the double-sided fixing members 11.
[0071] The outer surface of the worm 52 has helical teeth that mesh with the worm wheel 51. By manually rotating the worm 52, the meshing action of the helical teeth and the worm wheel 51 converts the axial rotational motion into the circumferential motion of the worm wheel 51, thereby driving the anti-detachment baffle 3 to rotate in the opposite direction around the extension of the double-sided fixing members 11, thus achieving precise angle adjustment of the anti-detachment baffle 3.
[0072] Once the anti-detachment baffle 3 is positioned to the target position by the angle adjustment device 5, it needs to be locked. In some embodiments, the angle adjustment device 5 further includes: a knob 54 and a limiting pin 55; the knob 54 is located at the end of the worm gear 52, and the knob 54 is manually rotated to drive the worm gear 52 to rotate; the knob 54 is provided with a plurality of slots 541 in the circumferential direction; the fixing member 11 is also provided with a limiting hole, one end of the limiting pin 55 is engaged with the limiting hole, and the other end of the limiting pin 55 is engaged with the slot 541 of the worm gear 51.
[0073] The specific operation process of adjusting and locking the anti-detachment baffle 3 by the angle adjustment device 5 is as follows: Manually rotate the knob 54 to drive the worm gear 52 to rotate. Under the meshing action of the threaded teeth of the worm gear 52, the rotational motion of the worm wheel 51 is converted into circumferential motion to drive the anti-detachment baffle 3 to rotate. When the anti-detachment baffle 3 is positioned to the target position, insert the limiting pin 55 into the limiting hole so that the end of the limiting pin 55 is engaged with the corresponding slot 541 on the knob 54, thereby limiting the rotation of the worm wheel 51 driven by the knob 54 and locking the anti-detachment baffle 3.
[0074] To enhance the motion stability and positioning accuracy of the anti-detachment baffle 3 angle adjustment, in some embodiments, the angle adjustment device 5 further includes a support assembly 56; the support assembly 56 includes a support rod 561, a slide rail 562, and a slider 563; the support rod 561 has a first end and a second end; the first end of the support rod 561 is hinged to the anti-detachment baffle 3; the slide rail 562 is mounted on the fixing member 11 along the axial direction of the vertical worm gear 51; the second end of the support rod 561 is slidably connected to the slide rail 562 through the slider 563. Specifically, the slider 563 includes a slide rod and a connecting member; both ends of the slide rod are respectively fixed to the second end of the support rod 561 through the connecting member; the slide rail 562 is provided with a movable through hole 5621 that slides with the slide rod.
[0075] During the angle adjustment of the anti-detachment baffle 3, its rotational motion is transmitted to the support rod 561 through the hinge mechanism, driving the slide rod to slide linearly along the movable through hole 5621 of the slide rail 562. This structure, by constraining the degree of freedom of the slide rod, converts the rotational motion of the anti-detachment baffle 3 into linear displacement within the slide rail 562, thereby providing stable radial support during adjustment, effectively balancing the torque load on the anti-detachment baffle 3, and ensuring that the anti-detachment baffle 3 maintains structural rigidity and positioning accuracy during dynamic adjustment.
[0076] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A dynamic anti-dislocation system for pediatric acetabular prostheses, characterized in that, include: Dynamic anti-detachment components include: fasteners; A gear mechanism includes: a gear and a transmission rack; a fixing member is provided on each side of the gear; the two fixing members are meshed with the gear through the transmission rack, and the gear rotates by the driving of the fixing members; The anti-dislodgement baffle is a retractable arc-shaped baffle; both ends of the anti-dislodgement baffle are respectively installed at the outer edge of the acetabulum through the fixing member, and the anti-dislodgement baffle is used to prevent the hemi-hip prosthesis ball head assembly from dislodging from the acetabulum.
2. The dynamic anti-dislocation system for pediatric acetabular prostheses according to claim 1, characterized in that, The dynamic anti-detachment component also includes: a housing; The housing has an inner cavity and a movable hole, the inner cavity being in communication with the movable hole; the gear is rotatably mounted in the inner cavity; one end of the transmission rack is connected to the corresponding fixed member, and the other end of the transmission rack extends into the inner cavity through the movable hole and meshes with the gear.
3. The dynamic anti-dislocation system for pediatric acetabular prostheses according to claim 2, characterized in that, Also includes: Ratchet mechanism; The ratchet mechanism includes: A ratchet is fixedly connected to the gear on the same axis. A check pawl, the fulcrum end of which is rotatably mounted in the inner cavity; the check pawl has a locking and limiting state that abuts against the ratchet teeth of the ratchet, and a disengaged state that is disengaged from the ratchet teeth of the ratchet when moved by an external force.
4. The dynamic anti-dislocation system for pediatric acetabular prostheses according to claim 3, characterized in that, A limiting member is provided around the anti-return pawl to restrict its swing.
5. The pediatric acetabular prosthesis dynamic anti-dislocation system according to claim 2, characterized in that, Also includes: Angle adjustment device; Both ends of the anti-detachment baffle are respectively installed on the corresponding fixing parts through the angle adjustment device; The angle adjustment device includes: The worm gear includes a toothed portion and a rim portion; the fixing member has a cavity inside, the toothed portion is rotatably disposed in the cavity, and the rim portion extends out of the cavity and is connected to the anti-detachment baffle; The worm gear, the fixing member is also provided with a socket that communicates with the cavity; the worm gear is inserted into the socket and meshes with the toothed part of the worm wheel, and the worm gear drives the worm wheel to rotate the anti-dislodgement baffle at the outer edge of the acetabulum; A rotating shaft, one end of which is connected to the worm gear, and the other end of which is rotatably connected to the housing, the rotating shaft rotating with the worm gear.
6. The dynamic anti-dislocation system for pediatric acetabular prostheses according to claim 5, characterized in that, The angle adjustment device further includes: A knob is located at the end of the worm gear, and the knob drives the worm gear to rotate; the knob is provided with multiple slots circumferentially. The fixing member is provided with a limiting pin and a limiting hole. One end of the limiting pin is inserted into the limiting hole, and the other end of the limiting pin is engaged with the slot.
7. The dynamic anti-dislocation system for pediatric acetabular prostheses according to claim 5, characterized in that, The angle adjustment device further includes: a support assembly; the support assembly includes: A support rod having a first end and a second end; the first end of the support rod is hinged to the anti-detachment baffle. The slide rail is mounted on the fixing member along the direction perpendicular to the axis of the worm gear; A sliding element is provided, wherein the second end of the support rod is slidably connected to the slide rail via the sliding element.
8. The pediatric acetabular prosthesis dynamic anti-dislocation system according to claim 7, characterized in that, The sliding component includes: a sliding rod and a connecting member; both ends of the sliding rod are respectively fixed to the second end of the support rod through the connecting member; the slide rail is provided with a movable through hole that cooperates with the sliding rod to slide.
9. The dynamic anti-dislocation system for pediatric acetabular prostheses according to claim 1, characterized in that, The anti-detachment baffle includes: The telescopic section includes two stacked side wing plates; Two arc-shaped baffles are respectively disposed on both sides of the telescopic part; the straight edge of each arc-shaped baffle is connected to a side wing plate, and the convex arc surface of the arc-shaped baffle is connected to the corresponding fixing member.
10. The dynamic anti-dislocation system for pediatric acetabular prostheses according to claim 1, characterized in that, The anti-detachment baffle has a smooth coating on its surface.
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