3D printing inner patellofemoral ligament reconstruction femoral tunnel positioner and preparation device thereof

Abstract

The utility model belongs to the technical field of medical instruments, and discloses a 3D printing inner patellofemoral ligament reconstruction femoral tunnel positioner and a preparation device thereof.The 3D printing inner patellofemoral ligament reconstruction femoral tunnel positioner comprises a first cylinder, a second cylinder, a bone adapting shell and an operating rod; wherein the diameter of the second cylinder is larger than that of the first cylinder, the length of the second cylinder is smaller than that of the first cylinder, the second cylinder is connected to the outer side of the first cylinder in a sleeving mode, the bone adapting shell is connected to the outer side of the second cylinder in a sleeving mode, and the operating rod is fixedly connected with the outer side of the second cylinder. The first cylinder can penetrate through a standard surgical incision, the second cylinder is connected to the first cylinder in a sleeving mode so that the operating rod and the bone adapting shell can be installed, the operating rod facilitates operation of the positioner, the positioner can be firmly attached to the posterior condylar groove of the femur through the bone adapting shell, therefore, perfect attachment to the femur is achieved, and the positioning accuracy is guaranteed.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction and its preparation device. Background Technology

[0002] Patellar dislocation refers to the patella dislocating from the trochlear notch of the femur during activity, and it often occurs in adolescents. Although habitual patellar dislocation is not very common in sports injuries, it is easily misdiagnosed or missed in clinical diagnosis because the patella can spontaneously reduce after dislocation. Patellar dislocation often occurs due to direct trauma such as running (especially when turning or twisting), lateral displacement during a half-squat (defensive movement in basketball), or lateral impact to the knee joint. Some patients with patellar dislocation may have their own anatomical abnormalities, such as systemic joint capsule laxity, high patella, and genu valgum (knock-knees). Most patellar dislocations are lateral dislocations. After dislocation, the stabilizing structures on the medial side of the patellofemoral joint, including the medial patellofemoral retinaculum, vastus medialis muscle, and medial patellofemoral ligament, are torn, leading to intra-articular hematoma and synovitis. During spontaneous reduction, the medial surface of the patella impacts the lateral surface of the femoral condyle, which can cause cartilage damage or tangential fracture.

[0003] A femoral tunnel locator is a medical device for precisely quantifying and locating the femoral tunnel. In existing technology, such as CN103892873B, a femoral tunnel locator for arthroscopic anterior cruciate ligament reconstruction is disclosed. This locator locates the femoral tunnel based on the distance and angle between preoperatively measured femoral physiological landmarks and the desired femoral tunnel. The locator includes a main rod with a guide hook at its front end, a sliding rod mounted on the main rod that can slide along its length, and a pair of lower swing arms movably mounted at the front end of the sliding rod. The lower swing arms are movably connected to a pair of upper swing arm scales movably mounted on the main rod, forming a quadrilateral structure. Moving the sliding rod adjusts the shape of the quadrilateral structure to achieve the specified angle between the upper swing arm scales, and the distance is read from the upper swing arm scales. This technical solution's shape and size are suitable for the needs of arthroscopic surgical incisions and joint cavity space, solving the problem of other tools being unable to enter the surgical incision and the narrow space of the joint cavity. Furthermore, it allows for one-time positioning based on angle and distance, avoiding soft tissue damage caused by repeated entry of instruments into the surgical incision.

[0004] Existing femoral tunnel locators cannot guarantee that the bone-fitting part inside the locator will firmly adhere to the posterior condyle groove of the femur when locating the femoral tunnel, resulting in insufficient positioning accuracy. Utility Model Content

[0005] The purpose of this application is to provide a 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction and its preparation device. By designing a suitable bone shell in the locator, the suitable bone shell can be firmly attached to the posterior condylar groove of the femur, thereby achieving perfect fit with the femur and ensuring the accuracy of positioning.

[0006] To achieve the above objectives, the following technical solution is adopted:

[0007] In a first aspect, this application provides a 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction, comprising a first cylinder, a second cylinder, a bone fitting shell, and an operating rod; wherein the diameter of the second cylinder is larger than the diameter of the first cylinder, the length of the second cylinder is smaller than the length of the first cylinder, the second cylinder is sleeved on the outside of the first cylinder, the bone fitting shell is sleeved on the outside of the second cylinder, and the operating rod is fixedly connected to the outside of the second cylinder.

[0008] Preferably, in the 3D-printed medial patellofemoral ligament reconstruction femoral tunnel locator as described above, the diameter of the second cylinder is twice the diameter of the first cylinder.

[0009] Preferably, in the 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction as described above, the length of the second cylinder is 1 / 3 of the length of the first cylinder.

[0010] Preferably, in the 3D-printed medial patellofemoral ligament reconstruction femoral tunnel locator as described above, the second cylinder is sleeved on the outer side of the middle part of the first cylinder.

[0011] Secondly, this application provides a fabrication apparatus for a 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction as described in the first aspect of this application, the fabrication apparatus comprising:

[0012] The model building module is configured to build a three-dimensional digital model of the knee joint using CT data of the patient's knee joint;

[0013] The first cylinder model generation module is connected to the model construction module. The first cylinder model generation module is configured to obtain the three-dimensional digital model of the knee joint constructed by the model construction module. Based on the determined femoral tunnel insertion point of the medial patellofemoral ligament, the first cylinder model is generated by simulating and reconstructing the femoral tunnel through the midline of the patella and the midline of the medial femoral condyle, and making a 4cm longitudinal incision through the femoral tunnel insertion point.

[0014] A locator model generation module is connected to the first cylinder model generation module. The locator model generation module is configured to wrap the femoral insertion point, the first cylinder model, and the adductor tubercle with the bone surface on one side of the medial patellofemoral ligament femoral insertion point, and peel off 2mm distally to form a suitable bone shell model for the locator, which is then saved as an STL file. The three-dimensional digital model of the knee joint, the first cylinder model, and the suitable bone shell model are imported into Materialise Magics 21.0 to create a second cylinder model and an operating rod model. The first cylinder model and the second cylinder model are overlapped. The second cylinder model is selected and translated and adjusted to a set position. The operating rod model is selected and adjusted to the most suitable position by translation and rotation. The suitable bone shell model, the second cylinder model, and the operating rod model are selected and combined into a composite. Boolean operation-reduction is performed on the composite and the femoral model to obtain the initial locator model. Then, Boolean algorithm-reduction is performed on cylinder I in the initial locator model to obtain the locator model, which is then saved as an STL file.

[0015] A 3D printing parameter generation module is connected to the locator model generation module. The 3D printing parameter generation module is configured to obtain a locator model from the locator model generation module and generate 3D printing parameters based on the locator model.

[0016] A 3D printer is connected to the 3D printing parameter generation module. The 3D printer is configured to print based on the 3D printing parameters to obtain a 3D printed medial patellofemoral ligament reconstruction femoral tunnel locator.

[0017] Preferably, in the preparation apparatus described above, the 3D printing parameter generation module is further configured to import the STL file of the locator model into Cura slicing, adjust the printing parameters, adjust the bone fusion surface upwards, adopt a full support method, set the wall thickness to 1.2 mm, set the infill rate to 50%, and export the 3D printing parameters in gcode format.

[0018] The beneficial effects of this application are:

[0019] This application allows the first cylinder to pass through a standard surgical incision, and the second cylinder to be fitted onto the first cylinder to install the operating rod and the bone fitting shell. The operating rod facilitates the operation of the locator, and the bone fitting shell can be firmly attached to the posterior condyle groove of the femur, thereby achieving perfect fit with the femur and ensuring accurate positioning. Attached Figure Description

[0020] Figure 1 The structure of a 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction according to Embodiment 1 of this application is shown. Figure 1 .

[0021] Figure 2 The structure of a 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction according to Embodiment 1 of this application is shown. Figure 2 .

[0022] Figure 3 A structural diagram of a fabrication apparatus for a 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction according to Embodiment 2 of this application is shown.

[0023] Figure 4 A schematic diagram of the structure of the first cylinder model generated by the first cylinder model generation module according to Embodiment 2 of this application is shown.

[0024] Figure 5 The diagram shows the structure of the bone shell model of the locator according to Embodiment 2 of this application, in which the bone surface of the medial patellofemoral ligament on one side of the femoral insertion point is wrapped around the femoral insertion point, the first cylindrical model and the adductor tubercle, and the shell is removed 2 mm distally.

[0025] Figure 6 A schematic diagram of the locator model structure according to Embodiment 2 of this application is shown.

[0026] Figure label:

[0027] 100, First cylinder; 200, Second cylinder; 300, Fitting shell; 400, Operating lever; 500, Model building module; 600, First cylinder model generation module; 700, Positioner model generation module; 800, 3D printing parameter generation module; 900, 3D printer. Detailed Implementation

[0028] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.

[0029] The specific implementation methods of this application will be further described in detail below with reference to the accompanying drawings and embodiments.

[0030] Example 1:

[0031] This application provides a 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction. For example... Figure 1As shown, the 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction includes a first cylinder 100, a second cylinder 200, a suitable bone shell 300, and an operating rod 400. The diameter of the second cylinder 200 is larger than the diameter of the first cylinder 100, and the length of the second cylinder 200 is smaller than the length of the first cylinder 100. The second cylinder 200 is fitted onto the outside of the first cylinder 100, the suitable bone shell 300 is fitted onto the outside of the second cylinder 200, and the operating rod 400 is fixedly connected to the outside of the second cylinder 200.

[0032] For example, the diameter of the second cylinder 200 is twice the diameter of the first cylinder 100. The length of the second cylinder 200 is one-third the length of the first cylinder 100. The second cylinder 200 is fitted onto the outer side of the middle portion of the first cylinder 100.

[0033] It should be noted that the above-described relative dimensions and positions of the first cylinder 100 and the second cylinder 200 are merely examples and do not constitute a limitation on this application. For example, in some embodiments, such as Figure 2 As shown, the end of the second cylinder 200 can be flush with the end of the first cylinder 100.

[0034] The working principle of this 3D-printed medial patellofemoral ligament reconstruction femoral tunnel locator is as follows:

[0035] The first cylinder 100 passes through the standard surgical incision. The second cylinder 200, fitted onto the first cylinder 100, serves to mount the bone fitting shell 300 and the operating rod 400. During use, the entire locator can be operated by holding the operating rod 400, allowing the first cylinder 100 to pass through the standard surgical incision. At this point, the bone fitting shell 300 serves to limit and conform to the incision. Limiting prevents the first cylinder 100 from passing excessively through the standard surgical incision, while conforming ensures that the bone fitting shell 300 fits snugly against the posterior condyle groove of the femur. Considering the different bone types of different patients, the shape of the bone fitting shell 300 is personalized based on the patient's preoperative CT 3D reconstruction data, such as using the posterior condyle groove of the femur as the conforming surface, so that the shape of the bone fitting shell 300 can perfectly conform to this conforming surface.

[0036] In this embodiment, the first cylinder 100, the second cylinder 200, the bone shell 300, and the operating rod 400 are all made of PEEK material, which is sterilized in low-temperature plasma for use in surgery.

[0037] Example 2:

[0038] This application provides a fabrication apparatus for a 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction. The specific structure of the 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction is described in Embodiment 1 of this application, and will not be repeated here. Figure 3 As shown, the fabrication device includes a model building module 500, a first cylinder model generation module 600, a locator model generation module 700, a 3D printing parameter generation module 800, and a 3D printer 900 connected in sequence.

[0039] The model building module 500 is configured to construct a three-dimensional digital model of the knee joint using CT data of the patient's knee joint. The CT data of the patient's knee joint is obtained by performing a CT scan of the patient's knee joint in extension position before surgery. The model building module can reconstruct a three-dimensional digital model of the affected knee joint using the CT data in Mimics 19.0.

[0040] For example, the model building module 500 is used to import CT scans into Mimics 19.0 and reconstruct a 3D digital model of the affected knee joint using the CT data. The cylinder I has a radius of 1.5 mm and a length of 150 mm; the cylinder II has a radius of 4.0 mm and a length of 30-60 mm.

[0041] The first cylindrical model generation module 600 is configured to obtain the three-dimensional digital model of the knee joint constructed by the model construction module 600. Based on the determined femoral tunnel insertion point of the medial patellofemoral ligament, the first cylindrical model is generated by simulating and reconstructing the femoral tunnel through the midline of the patella and the midline of the medial femoral condyle, and making a 4cm longitudinal incision through the femoral tunnel insertion point.

[0042] In this embodiment, according to the classic The method for determining the femoral tunnel insertion point of the medial patellofemoral ligament is not described in detail here. The first cylinder model generated by the first cylinder model generation module 600 is as follows: Figure 4 As shown.

[0043] The locator model generation module 700 is configured to wrap the femoral insertion point, the first cylinder model, and the adductor tubercle with the bone surface on one side of the medial patellofemoral ligament femoral insertion point, and peel it 2mm distally to form the locator's bone shell model, which is then saved as an STL file. The knee joint 3D digital model, the first cylinder model, and the bone shell model are imported into Materialise Magics 21.0 to create a second cylinder model and an operating rod model. The first and second cylinder models are overlapped. The second cylinder model is selected and translated and adjusted to the set position. The operating rod model is selected and adjusted to the most suitable position by translation and rotation. The bone shell model, the second cylinder model, and the operating rod model are selected and combined into a composite. Boolean operation-reduction is performed on the composite and the femoral model to obtain the initial locator model. Then, Boolean algorithm-reduction is performed on cylinder I in the initial locator model to obtain the locator model, which is then saved as an STL file.

[0044] In this embodiment, the bone surface on one side of the femoral insertion point of the medial patellofemoral ligament wraps around the femoral insertion point, the first cylindrical model, and the adductor tubercle, and peels off 2mm distally to form the appropriate bone shell model of the locator. The specific implementation process of saving it as an STL file is as follows: the locator model generation module 700 selects the bone fitting surface of the locator in Geomagic Studio 2015 so that it can surround the femoral insertion point and the first cylindrical model, and the upper, lower, and anterior boundaries are 10mm, 5mm, and 15mm away from the edge, respectively, and the posterior boundary is 15mm away from the adductor tubercle.

[0045] Please see Figure 5 and Figure 6 , Figure 5 The diagram shows the process of wrapping the femoral insertion point, the first cylindrical model, and the adductor tubercle with the bone surface of the medial patellofemoral ligament on one side, and then removing the shell 2 mm distally to form a suitable bone shell model for the locator. Figure 6 The final locator model is shown.

[0046] The 3D printing parameter generation module 800 is configured to obtain the locator model from the locator model generation module 700 and generate 3D printing parameters based on the locator model.

[0047] In some embodiments, the 3D printing parameter generation module is further configured to import the STL file of the locator model into Cura slicing, adjust the printing parameters, adjust the bone fitting surface upwards, adopt a full support method, set the wall thickness to 1.2 mm, set the infill rate to 50%, and export the 3D printing parameters in gcode format.

[0048] A 3D printer 900 was configured to print based on 3D printing parameters to obtain a 3D printed femoral tunnel locator for medial patellofemoral ligament reconstruction.

[0049] It is important to note that the 3D printer uses PEEK material, which is sterilized in low-temperature plasma for use in surgery. After printing and removing the supporting structure, a 3D-printed femoral tunnel locator is obtained for personalized MPFL reconstruction.

[0050] The above embodiments are only used to illustrate this application and are not intended to limit this application. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of this application. Therefore, all equivalent technical solutions also fall within the scope of this application, and the patent protection scope of this application should be defined by the claims.

Claims

1. A 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction, characterized in that, It includes a first cylinder, a second cylinder, a bone fitting shell, and an operating rod; wherein, the diameter of the second cylinder is larger than the diameter of the first cylinder, the length of the second cylinder is smaller than the length of the first cylinder, the second cylinder is sleeved on the outside of the first cylinder, the bone fitting shell is sleeved on the outside of the second cylinder, and the operating rod is fixedly connected to the outside of the second cylinder.

2. The 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction as described in claim 1, characterized in that, The diameter of the second cylinder is twice the diameter of the first cylinder.

3. The 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction as described in claim 1, characterized in that, The length of the second cylinder is 1 / 3 of the length of the first cylinder.

4. The 3D-printed femoral tunnel locator for medial patellofemoral ligament reconstruction as described in claim 1, characterized in that, The second cylinder is fitted onto the outer side of the middle part of the first cylinder.

5. The fabrication apparatus for a 3D-printed medial patellofemoral ligament reconstruction femoral tunnel locator as described in any one of claims 1 to 4, characterized in that, The preparation apparatus includes: The model building module is configured to build a three-dimensional digital model of the knee joint using CT data of the patient's knee joint; The first cylinder model generation module is connected to the model construction module. The first cylinder model generation module is configured to obtain the three-dimensional digital model of the knee joint constructed by the model construction module. Based on the determined femoral tunnel insertion point of the medial patellofemoral ligament, the first cylinder model is generated by simulating and reconstructing the femoral tunnel through the midline of the patella and the midline of the medial femoral condyle, and making a 4cm longitudinal incision through the femoral tunnel insertion point. A locator model generation module is connected to the first cylinder model generation module. The locator model generation module is configured to wrap the femoral insertion point, the first cylinder model, and the adductor tubercle with the bone surface on one side of the medial patellofemoral ligament femoral insertion point, and peel off 2mm distally to form a suitable bone shell model for the locator, which is then saved as an STL file. The three-dimensional digital model of the knee joint, the first cylinder model, and the suitable bone shell model are imported into Materialise Magics 21.0 to create a second cylinder model and an operating rod model. The first cylinder model and the second cylinder model are overlapped. The second cylinder model is selected and translated and adjusted to a set position. The operating rod model is selected and adjusted to the most suitable position by translation and rotation. The suitable bone shell model, the second cylinder model, and the operating rod model are selected and combined into a composite. Boolean operation-reduction is performed on the composite and the femoral model to obtain the initial locator model. Then, Boolean algorithm-reduction is performed on cylinder I in the initial locator model to obtain the locator model, which is then saved as an STL file. A 3D printing parameter generation module is connected to the locator model generation module. The 3D printing parameter generation module is configured to obtain a locator model from the locator model generation module and generate 3D printing parameters based on the locator model. A 3D printer is connected to the 3D printing parameter generation module. The 3D printer is configured to print based on the 3D printing parameters to obtain a 3D printed medial patellofemoral ligament reconstruction femoral tunnel locator.

6. The preparation apparatus as described in claim 5, characterized in that, The 3D printing parameter generation module is further configured to import the STL file of the locator model into Cura slicing, adjust the printing parameters, adjust the bone fitting surface upwards, adopt a full support method, set the wall thickness to 1.2mm, set the infill rate to 50%, and export the 3D printing parameters in gcode format.

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