Bionic acetabular reconstruction prosthesis with periacetabular bone integration and its design method

Abstract

The present invention relates to a bionic acetabular reconstruction prosthesis with bone integration around the acetabulum and a design method thereof, comprising the steps of collecting pelvic CT data of a patient; reconstructing a personalized pelvic 3D model; trimming and 3D printing the personalized pelvic 3D model to obtain a pelvic physical model; designing a personalized acetabular reconstruction prosthesis model that accurately matches the acetabular rim of the trimmed personalized pelvic 3D model and 3D printing to obtain a prosthesis physical model; assembling the prosthesis physical model with the pelvic physical model to determine whether the two fit closely, if not, adjusting the parameters of the personalized acetabular reconstruction prosthesis model and reprinting until the prosthesis physical model fits closely with the pelvic physical model; 3D printing the personalized acetabular reconstruction prosthesis model to obtain a bionic acetabular reconstruction prosthesis. The present invention has the characteristics of being fixed and stable, not easy to loosen, and has a lower revision rate, can relieve the patient's pain, restore the function of the affected limb, and improve the patient's quality of life.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a bionic acetabular reconstruction prosthesis integrated with periacetabular bones and a design method thereof. Background Art

[0002] As the number of patients undergoing hip replacement in my country increases year by year, the number of patients who need hip revision is also increasing. In hip revision surgery, the reconstruction of acetabular bone defects is a difficult problem faced by orthopedic surgeons because the types of acetabular bone defects are complex and varied. The most commonly used classification of acetabular bone defects in clinical practice is the Paprosky classification. The Paprosky classification refers to whether the teardrop, sciatic, and Kohler lines are dissolved and whether the acetabular cup has moved upward to determine whether there are bone defects in the anterior, posterior, inner, and superior walls of the acetabulum and the severity of the defects. The specific classifications are shown in Table 1:

[0003] Table 1

[0004]

[0005] Among them, pelvic defects above Type IIIB are the most difficult to reconstruct the acetabulum. The conventional acetabulum reconstruction methods commonly used in clinical practice mainly include:

[0006] (1) Trabecular Metal Augment and Shell

[0007] Its features are:

[0008] 1) The secondary revision rate and radiographic loosening rate are relatively the lowest;

[0009] 2) Polyethylene prostheses have a high dislocation rate, and restrictive polyethylene prostheses may reduce the dislocation rate, but the risk of loosening is increased.

[0010] (2) Bone Impaction Grafting with Metal Mesh

[0011] Its features are:

[0012] 1) It cannot be used in patients with discontinuous pelvic structures;

[0013] 2) Paprosky classification ⅢB is not effective.

[0014] (3) Hemispherical Implant with Hook and Flanges

[0015] Its features are:

[0016] 1) The effect is not satisfactory, and the secondary revision rate and loosening rate are high;

[0017] 2) Mostly used for Paprosky classification ⅢA.

[0018] (4) Trabecular Metal Augment or Structural Allograft with Cup

[0019] Its features are:

[0020] 1) Bone grafting is suitable for Paprosky ⅢA.

[0021] (5) Custom-Made Triflange Component

[0022] Its features are:

[0023] 1) The main disadvantages are that accurate imaging images are required for reconstruction, reconstruction and manufacturing take a long time and are expensive, and the prosthesis cannot be modified during surgery.

[0024] (6) Acetabular reinforcement ring (cage), such as antiprotrusion reinforcement ring (Antiprotrusion Cage), Kerboull type acetabular reinforcement device (Kerboull reinforcement device), Burch-Schneider type acetabular reinforcement ring (Burch-Schneider cage), Richards contour reinforcement ring (Richards contour cage), etc.

[0025] Features are:

[0026] 1) High incidence of radiographic loosening;

[0027] 2) Suitable for elderly people with low requirements. Young people are prone to prosthesis fracture due to poor biological ingrowth and stability.

[0028] The key problems commonly encountered in the currently commonly used conventional acetabular reconstruction methods are high revision rate, unstable prosthesis fixation, easy loosening, and few prostheses suitable for acetabular defects above grade IIIB, resulting in less than ideal treatment effects for acetabular bone defects. Summary of the invention

[0029] In order to solve the problems of high revision rate, unstable fixation, easy loosening, etc. of acetabular defect reconstruction prosthesis in the prior art, the present invention provides a bionic acetabular reconstruction prosthesis with periacetabular bone integration and a design method thereof. The design method is a bionic morphological fitting design method that can customize the prosthesis according to the patient's bone model. The method is based on the collected patient pelvic CT data, uses Mimics software and Magics software to realize the design of a personalized pelvic 3D model, uses Unigraphics NX software to realize the design of a personalized acetabular reconstruction prosthesis model that matches the personalized pelvic 3D model, and uses 3D printing technology to optimize the design of the personalized acetabular reconstruction prosthesis model, and finally obtains a bionic acetabular reconstruction prosthesis that can be fixed to the pelvis by screws.

[0030] To achieve the above object, the present invention adopts the following technical solutions:

[0031] A method for designing a bionic acetabular reconstruction prosthesis with periacetabular bone integration, the method comprising the following steps:

[0032] Step 1: Acquire pelvic CT data of the patient including the hip joint and part of the femur, and import the pelvic CT data into Mimics software;

[0033] Step 2: Reconstructing a personalized pelvic 3D model of the patient based on the pelvic CT data in Mimics software;

[0034] Step 3: Import the personalized pelvis 3D model into Magics software in STL file format, perform model trimming, and perform 3D printing on the trimmed personalized pelvis 3D model to obtain a physical pelvis model;

[0035] Step 4: using Unigraphics NX software to design a personalized acetabular reconstruction prosthesis model that accurately matches the acetabular rim of the trimmed personalized pelvic 3D model, the personalized acetabular reconstruction prosthesis model includes an acetabular surface, a sciatic ramus, a pubic ramus, and an iliac wing ramus, and the sciatic ramus, the pubic ramus, and the iliac wing ramus are respectively provided with screw holes for fixing to the pelvis, and the personalized acetabular reconstruction prosthesis model is 3D printed to obtain a physical model of the prosthesis;

[0036] Step 5: Assemble the prosthesis physical model with the pelvis physical model to determine whether the prosthesis physical model and the pelvis physical model fit closely together. If so, proceed to step 6; if not, return to step 4, adjust the parameters of the personalized acetabulum reconstruction prosthesis model in Unigraphics NX software and reprint it until the reprinted prosthesis physical model fits closely together with the pelvis physical model.

[0037] Step six: 3D printing the personalized acetabular reconstruction prosthesis model to obtain a bionic acetabular reconstruction prosthesis.

[0038] Correspondingly, the present invention also proposes a periacetabular bone-integrated bionic acetabular reconstruction prosthesis, which is designed by adopting the above-mentioned design method of the periacetabular bone-integrated bionic acetabular reconstruction prosthesis.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] (1) The present invention realizes the bionic reconstruction of the anatomical morphology of the defect site above grade IIIB and the biomechanical conduction of the pelvis by integrated design of the morphology of the acetabulum;

[0041] (2) The bionic acetabular reconstruction prosthesis adopts a bionic morphological fit design around the acetabulum, and uses the fit of micropores and bones to achieve maximum bone integration, thereby achieving biological long-term fixation, with the characteristics of stable fixation and not easy to loosen;

[0042] (3) The revision rate is lower, which can reduce the patient's pain, restore the function of the affected limb, and improve the patient's quality of life. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A flow chart of a design method of a bionic acetabular reconstruction prosthesis with periacetabular bone integration according to the present invention;

[0044] Figure 2 A schematic diagram of the personalized pelvic 3D model of the present invention;

[0045] Figure 3 for Figure 2 Lateral view of the middle left portion of the pelvis;

[0046] Figure 4 A schematic diagram of a personalized acetabular reconstruction prosthesis model in the present invention;

[0047] Figure 5 Another schematic diagram of the personalized acetabular reconstruction prosthesis model of the present invention;

[0048] Figure 6 A schematic diagram of the assembly of a personalized acetabular reconstruction prosthesis model and a modified personalized pelvic 3D model;

[0049] Figure 7 for Figure 6 Side view of the left part of the pelvis and the personalized acetabular reconstruction prosthesis model;

[0050] Figure 8 This is an X-ray image of the patient's pelvis after surgery. DETAILED DESCRIPTION

[0051] The technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0052] The present invention customizes a personalized 3D printed acetabular periosseous integrated bionic acetabular reconstruction prosthesis based on the patient's hip joint CT image. The prosthesis can relieve the patient's pain, restore the function of the affected limb, and improve the patient's quality of life. Figure 1 As shown, the specific design method of the acetabular periosseous integration bionic acetabular reconstruction prosthesis of the present invention comprises the following steps:

[0053] Step 1: Collect the patient's pelvic CT data including the defective hip joint and part of the femur, and import the pelvic CT data into Mimics software.

[0054] Step 2: Reconstruct the patient's personalized pelvic 3D model based on the pelvic CT data in Mimics software, such as Figure 2 As shown, the personalized pelvis 3D model includes the entire pelvis. Figure 3 Shown Figure 2 Lateral view of the middle left portion of the pelvis.

[0055] Step 3: Import the reconstructed personalized pelvic 3D model into Magics software in STL file format, trim the model, and use a stereolithography (SLA) 3D printer to 3D print the trimmed personalized pelvic 3D model using photosensitive resin to obtain a physical pelvic model. The printed pelvic model provides guidance and design ideas for the preoperative design of complex acetabular prostheses and the production of personalized prostheses.

[0056] Step 4: Use Unigraphics NX software to design a personalized acetabular reconstruction prosthesis model that accurately matches the acetabular rim of the modified personalized pelvic 3D model. The design process mainly includes the extraction of the prosthetic acetabular surface, the design of the sciatic branch, pubic branch and iliac wing branch, and the design of the screw hole, such as Figure 4 and Figure 5 As shown in the figure, the designed personalized acetabular reconstruction prosthesis model includes the acetabular surface, the sciatic ramus, the pubic ramus and the iliac wing ramus, the sciatic ramus, the pubic ramus and the iliac wing ramus are respectively connected to the acetabular surface, and the sciatic ramus, the pubic ramus and the iliac wing ramus are respectively provided with screw holes for fixing with the pelvis. Figure 6 The figure shows the assembly diagram of the personalized acetabular reconstruction prosthesis model and the modified personalized pelvic 3D model. Figure 7 for Figure 6 The side view of the left side of the pelvis and the personalized acetabular reconstruction prosthesis model. The personalized acetabular reconstruction prosthesis model is then 3D printed using a stereolithography (SLA) 3D printer using photosensitive resin to obtain a physical model of the prosthesis.

[0057] Step 5: Perform an in vitro matching test on the printed pelvic model and the prosthesis model, i.e., assemble them, which can provide guidance for the adjustment of the prosthesis model and the surgical method. Specifically, when assembling the printed prosthesis model with the pelvic model, determine whether the prosthesis model and the pelvic model fit tightly according to the assembly situation. If the prosthesis model and the pelvic model fit tightly, it means that the design of the prosthesis is qualified, and go directly to step 6; if the prosthesis model and the pelvic model do not fit tightly enough and there is a gap, it means that the prosthesis design is unqualified. At this time, it is necessary to return to step 4, adjust the parameters of the personalized acetabular reconstruction prosthesis model in the Unigraphics NX software and reprint it, and then perform the assembly test until the reprinted prosthesis model and the pelvic model can fit tightly, thereby obtaining the final personalized acetabular reconstruction prosthesis model.

[0058] Furthermore, when assembling the prosthesis model with the pelvis model, in addition to judging whether the prosthesis model fits tightly with the pelvis model, it is also necessary to judge whether the sciatic branch, pubic branch and iliac wing branch are easy to fix to the pelvis model. For example, if the coverage of the iliac wing is too small, the sciatic branch and pubic branch are too long, etc., it will make it difficult for the prosthesis model to be placed and fixed on the pelvis model, that is, it is difficult for the bionic acetabulum reconstruction prosthesis to be placed and fixed to the patient's pelvis. Therefore, if the sciatic branch, pubic branch and iliac wing branch are not easy to fix to the pelvis model, then in Unigraphics When adjusting the parameters of the personalized acetabular reconstruction prosthesis model in NX software, it is also necessary to adjust the length, coverage area, and number of screw holes of the sciatic branch, pubic branch, and iliac wing branch. For example, if the coverage of the iliac wing is too small, the iliac wing branch can be appropriately extended to increase the coverage of the iliac wing to strengthen fixation; if the sciatic branch and pubic branch are too long and difficult to place, part of the sciatic branch and pubic branch can be removed, leaving only one screw hole to shorten the length and facilitate placement and fixation. Alternatively, a modular design can be used for the sciatic branch, pubic branch, and iliac wing branch, and the modules can be connected or removed according to the actual needs during the operation.

[0059] Step 6: 3D print the personalized acetabular reconstruction prosthesis model corresponding to the prosthesis physical model that can fit closely with the pelvic physical model, and the final designed bionic acetabular reconstruction prosthesis can be obtained. Optionally, the bionic acetabular reconstruction prosthesis is printed by an EBM printer using a Ti-6Al-4V alloy material, and the material of the bionic acetabular reconstruction prosthesis can also be selected from other biological materials that can be used for 3D printing.

[0060] Accordingly, in another embodiment, the present invention further proposes a bionic acetabular reconstruction prosthesis with periacetabular bone integration, which is designed by the design method described in the above embodiment. The specific steps of the design method can be found in the above embodiment, so they will not be described here. Figure 8 The figure shows an X-ray image of the patient's pelvis about one and a half months after the operation when the bionic acetabular reconstruction prosthesis with periacetabular bone integration of the present invention was applied to the reconstruction of the patient's acetabular defect. Clinical experiments have shown that the bionic acetabular reconstruction prosthesis of the present invention can fit well with the patient's acetabulum morphology, has a reasonable bionic design, and the patient's joint function recovers well after the operation.

[0061] Furthermore, after the implantation of the prosthesis, the prosthesis design is fed back and optimized in combination with the actual operation during the operation. During the operation, it was found that the repair of the acetabulum shape was troublesome and needed to be repaired to be relatively flat suitable for the prosthetic acetabular surface. Therefore, subsequent improvements can be combined with the design of an acetabular file to facilitate the repair of the acetabulum during the operation. The acetabular file has an outer edge. When repairing the circular side of the acetabulum, its outer edge can flatten the bulge of the defective outer edge, which is more conducive to the stable fixation of the prosthesis.

[0062] The present invention proposes a bionic acetabular reconstruction prosthesis with bone integration around the acetabulum and a design method thereof. The design method is a bionic morphological fitting design method that can customize the prosthesis according to the patient's bone model. The design of the personalized pelvic 3D model is realized based on the collected patient pelvic CT data, and the personalized acetabular reconstruction prosthesis model matching the personalized pelvic 3D model is realized by using Unigraphics NX software, and the personalized acetabular reconstruction prosthesis model is optimized and designed by using 3D printing technology, and finally a bionic acetabular reconstruction prosthesis that can be fixed with the pelvis by screws is obtained. The present invention realizes the bionic reconstruction of the anatomical morphology suitable for the defect site above grade IIIB and the biomechanical conduction of the pelvis by integrating the morphology of the acetabulum. The bionic acetabular reconstruction prosthesis adopts the fitting design of the bionic morphology around the acetabulum, and realizes the maximum area of ​​bone integration by fitting the micropores with the bone, thereby realizing biological long-term fixation, having the characteristics of stable fixation and not easy to loosen, and having a lower revision rate, which can relieve the patient's pain, restore the function of the affected limb, and improve the patient's quality of life.

[0063] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0064] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A design method for a bionic acetabular reconstruction prosthesis with periacetabular bone integration, characterized in that: The following steps are involved: Step 1: Acquire pelvic CT data of the patient including the hip joint and part of the femur, and import the pelvic CT data into Mimics software; Step 2: Reconstructing a personalized pelvic 3D model of the patient based on the pelvic CT data in Mimics software; Step 3: Import the personalized pelvis 3D model into Magics software in STL file format, perform model trimming, and perform 3D printing on the trimmed personalized pelvis 3D model to obtain a physical pelvis model; Step 4: using Unigraphics NX software to design a personalized acetabular reconstruction prosthesis model that accurately matches the acetabular rim of the trimmed personalized pelvic 3D model, the personalized acetabular reconstruction prosthesis model includes an acetabular surface, a sciatic ramus, a pubic ramus, and an iliac wing ramus, and the sciatic ramus, the pubic ramus, and the iliac wing ramus are respectively provided with screw holes for fixing to the pelvis, and the personalized acetabular reconstruction prosthesis model is 3D printed to obtain a physical model of the prosthesis; Step 5: Assemble the prosthesis physical model with the pelvis physical model, and determine whether the prosthesis physical model and the pelvis physical model fit closely. If so, proceed to step 6; if not, return to step 4, adjust the parameters of the personalized acetabular reconstruction prosthesis model in the Unigraphics NX software and reprint until the reprinted prosthesis physical model and the pelvis physical model fit closely. When assembling the prosthesis physical model with the pelvis physical model, determine whether the ischial ramus, the pubic ramus and the iliac wing ramus are easy to fix to the pelvis physical model. If not, when adjusting the parameters of the personalized acetabular reconstruction prosthesis model in the Unigraphics NX software, adjust the length, coverage area and number of screw holes of the ischial ramus, the pubic ramus and the iliac wing ramus. Step six: 3D printing the personalized acetabular reconstruction prosthesis model to obtain a bionic acetabular reconstruction prosthesis.

2. The method for designing a bionic acetabular reconstruction prosthesis with periacetabular bone integration according to claim 1, characterized in that: The pelvis physical model and the prosthesis physical model are both printed by a stereolithography 3D printer using photosensitive resin.

3. The method for designing a bionic acetabular reconstruction prosthesis with periacetabular bone integration according to claim 1, characterized in that: The bionic acetabular reconstruction prosthesis is printed by an EBM printer using a Ti-6Al-4V alloy material.

4. A bionic acetabular reconstruction prosthesis with periacetabular bone integration, characterized in that: The method is designed according to any one of claims 1 to 3.

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