CN115245409A

CN115245409A - Integrated acetabulum revision prosthesis based on 3D printing and preparation method thereof

Info

Publication number: CN115245409A
Application number: CN202111190009.XA
Authority: CN
Inventors: 王友华; 徐华; 陈民浩; 张健华
Original assignee: Affiliated Hospital of Nantong University
Current assignee: Affiliated Hospital of Nantong University
Priority date: 2021-10-13
Filing date: 2021-10-13
Publication date: 2022-10-28

Abstract

The invention provides an integrated acetabulum revision prosthesis based on 3D printing, which comprises an acetabulum cup and wing plates, wherein the wing plates are integrally formed at the side of the acetabulum cup through the 3D printing technology, nail channels are processed on the acetabulum cup and the wing plates, and all the nail channels are not interfered with each other. The nail passage arranged on the acetabulum cup comprises 3 iliac nail passages and 1 pubis nail passage. The acetabulum revision prosthesis prepared by the 3D printing technology can be consistent with the irregular shape height of a bone dissolving area around the acetabulum prosthesis, is prepared by titanium alloy materials, has the elastic modulus close to that of a normal bone, and has good mechanical adaptation and shape adaptation.

Description

Integrated acetabulum revision prosthesis based on 3D printing and preparation method thereof

Technical Field

The invention relates to the field of individualized medical endoprostheses, in particular to an integrated acetabulum revision prosthesis based on 3D printing and a preparation method thereof.

Background

Artificial total hip arthroplasty is an effective method for treating final hip arthropathy, the number of initial total hip arthroplasty is increasing year by year around the world, and even if the operation is successful, partial patients need to perform hip revision due to various reasons such as prosthesis loosening, joint instability, joint infection and the like. Reports have shown that the number of total american hip arthroplasties in 2005 was 40800, with an expected 2030 increase to 96700, an increase of approximately 137%.

After hip replacement, periprosthetic osteolysis, infection and the like are main reasons of failure and revision after hip replacement, and the key of success of revision is reconstruction of large-range and irregular anatomical bone defects of pelvis caused by osteolysis, infection and the like.

In the prior art, the treatment of the wide-range bone defect of the pelvis around the hip joint prosthesis comprises the steps of treating a large amount of allogeneic or autologous bones, applying bone cement, and using standard prostheses or revision prostheses for the prostheses. The main problems with these approaches are as follows: in the former, the bone reconstruction time of the value bone is too long, the early prosthesis stability cannot be provided, and the value bone repair reconstruction is easy to generate revision prosthesis displacement; in the latter case, although early stability is still acceptable, interfacial loosening occurs sooner or later due to the presence of an interface with bone that does not heal.

During the revision process, osseointegration of the revision prosthesis is subject to two main conditions: (1) Good initial stability must be obtained, micro-movements between the prosthesis and the bone should be less than 50 μm, micro-movements greater than 150 μm causing bone resorption and fibrous tissue ingrowth and eventually loosening of the prosthesis; (2) There is sufficient contact area between the prosthesis and the host bone, and most physicians believe that the acetabulum should cover at least 50% more of the prosthesis on the X-ray plate. However, when the bone defect is severe enough, the structural support of the acetabulum is damaged, and the continuity of the pelvis is even interrupted, so that the acetabular prosthesis trial can only achieve partial initial stability or has no initial stability at all.

Disclosure of Invention

The invention aims to solve the technical problems and provides an integrated acetabulum revision prosthesis based on 3D printing and a preparation method thereof, and the pelvis revision prosthesis prepared by adopting the 3D printing technology can be consistent with the irregular form height of a osteolysis region around the pelvis prosthesis and has good mechanical adaptation and form adaptability.

In order to solve the technical problems, an embodiment of the invention provides an integrated acetabulum revision prosthesis based on 3D printing, which comprises an acetabulum cup and wing plates, wherein the wing plates are integrally formed at the sides of the acetabulum cup, nail channels are machined on the acetabulum cup and the wing plates, and all the nail channels are not interfered with each other.

Wherein, the nail path arranged on the acetabulum cup comprises 3 iliac nail paths and 1 pubis nail path.

Wherein, the pterygoid lamina of wherein one side of acetabular cup is the ilium pterygoid lamina, be equipped with at least 2 ilium pterygoid lamina nail ways on the ilium pterygoid lamina.

Wherein, the integrated acetabulum revision prosthesis based on 3D printing further comprises a trabecular bone structure filled between the outer sides of the acetabulum cup and the nail passage and the acetabulum of the patient.

Further, the thickness of the trabecular bone structure on the outer side of the acetabular cup is 1.5mm, and the thickness of the trabecular bone structure on the lateral side of the wing plate is 1.5mm.

Wherein, 3 ilium position nail way be from the entity nail way of acetabular cup downwardly extending.

The invention also provides a preparation method of the integrated acetabulum revision prosthesis based on 3D printing, which comprises the following steps:

(1) Carrying out three-dimensional CT scanning on bilateral hip joints of a patient in a preoperative personalized manner, requiring a thin-layer CT (computed tomography) and dicom format which is not more than 1mm, including a diseased part, reserving redundant length, and shooting complete pelvic data, wherein the length is from the waist 4 to the position of the femoral lesser tuberosity;

(2) Optimizing original data of CT scanning, extracting and reconstructing bone substances by using reverse software, and planning prosthesis design after acquiring a required bone substance model;

(3) Selecting a proper metal acetabular cup three-dimensional model according to the shape and structure of the acetabular bone defect of each patient, pouring software for simulation, measuring the diameter of the acetabulum on the affected side, and designing the angle of the acetabulum on the affected side by combining the positions of the acetabulum on the affected side and the healthy side, wherein the angle comprises various parameters such as abduction angle and anteversion angle;

(4) Planning and designing the prosthesis according to the positioned acetabular cup and the acetabular defect state, filling the defect, adding wing plates, considering the stress direction, auxiliary support filling and the like, and obtaining the optimized and most matched three-dimensional reconstruction configuration of the acetabular cup prosthesis; performing preoperative simulation installation on the pelvis revision prosthesis obtained by three-dimensional reconstruction through a computer-aided design technology;

(5) According to the affected side acetabulum defect form, the force transmission and the support are considered, and meanwhile, the integrated acetabulum revision prosthesis design is carried out by considering the intraoperative implantation and the postoperative prosthesis bone growth conditions: the integrated acetabulum revision prosthesis comprises an acetabulum cup and wing plates, wherein the wing plates are integrally formed at the side of the acetabulum cup, and nail tracks are processed on the acetabulum cup and the wing plates; the integral acetabulum revision prosthesis comprises an acetabulum cup, a nail path and wing plates which are solid bodies, and the rest of the wing plates are bone trabecula structures; the thickness of the trabecular bone of the wing plate part is 1.5mm, the thickness of the trabecular bone of the cup body is 1.5mm, and the filling cushion blocks except the solid nail path are all in a trabecular bone structure;

(6) After the acetabulum prosthesis design is finished, printing a resin pelvis model and a prosthesis model for preoperative in vitro simulation;

(7) After confirming that no other modification is needed after the simulation, an engineer performs model slicing, a file identified by a printer is manufactured, and an Arcam Q10 printer is used for printing the acetabular prosthesis for later use.

Preferably, the acetabular cup, the wing plate and the nail path are made of titanium alloy materials, and the elastic modulus of the materials is close to that of normal bones.

The technical scheme of the invention has the following beneficial effects:

1. the acetabulum revision prosthesis prepared by the 3D printing technology can be consistent with the irregular shape height of a bone dissolving area around the acetabulum prosthesis, is prepared by titanium alloy materials, has the elastic modulus close to that of a normal bone, and has good mechanical adaptation and shape adaptation.

2. 3D prints customization acetabular bone false body and follows the reverse design of patient's pelvis data, has realized the individualized false body replacement of operation position, not only highly coincide with acetabular bone defect in the appearance, and the integral structure also makes things convenient for the intraoperative installation, has avoided too much bone grafting and unnecessary to cut the bone and the screw and bone cement between the implant are fixed to the initial stability of operation security and false body has been guaranteed.

3. According to the invention, the individualized acetabular revision prosthesis based on the 3D printing technology can be subjected to individualized screw hole design according to different osteolysis parts and fixing strength requirements, and the initial stability and the immediate stability of the acetabular revision prosthesis can be favorably enhanced through the unique design of locking screws, cortical bone screws and cancellous bone screws, particularly the closed hole hooks. The direction, the position and the length of the nail path are planned and designed before the operation, and the screw fixation is completed once in the operation, so that repeated debugging and errors are avoided, the operation steps are simplified, and the accuracy and the safety are improved.

4. The 3D printing process can enable the surface of the acetabulum revision prosthesis to be designed to form a microporous structure, and the appropriate porosity and pore diameter are favorable for bone growth of an inner plant-bone interface so as to ensure the long-term stability of an implant.

Drawings

FIG. 1 is a CT view of the acetabulum of a patient according to one embodiment of the invention;

FIG. 2 is a three-dimensional digital model of the acetabulum of a patient according to one embodiment;

FIG. 3 is a partial view of a three-dimensional digital model of a patient's acetabulum according to one embodiment;

FIG. 4 is a diagram illustrating measurement of diameter of an affected acetabulum in accordance with one embodiment;

FIG. 5 is a view of a simulated acetabular prosthesis placement position in accordance with one embodiment;

FIG. 6 is a view showing hip socket angle measurement in the first embodiment;

FIG. 7 is a schematic view of the one-piece acetabular revision prosthesis prepared in the first embodiment;

FIG. 8 is a diagram illustrating the positions of nail holes formed in the three-dimensional digital model according to the first embodiment;

FIG. 9 is a schematic structural view of the integrated acetabular revision prosthesis according to the first embodiment after connection with the three-dimensional digital model;

FIG. 10 is a CT view of the acetabulum of a patient according to a second embodiment of the invention;

FIG. 11 is a three-dimensional digital mockup of the acetabulum of the patient according to the second embodiment;

FIG. 12 is a partial view of a three-dimensional digital model of the acetabulum of the patient according to the second embodiment;

FIG. 13 is a diameter measurement of the affected acetabulum position in the second embodiment;

FIG. 14 is a view of the simulated acetabular prosthesis placement in the second embodiment;

FIG. 15 is a hip socket angle measuring view in the second embodiment;

FIG. 16 is a schematic structural view of the one-piece acetabular revision prosthesis prepared in the second embodiment;

FIG. 17 is a view showing positions of nail holes provided in the three-dimensional digital model according to the second embodiment;

FIG. 18 is a schematic structural view of the integrated acetabular revision prosthesis according to the second embodiment after connection with the three-dimensional digital model.

Description of reference numerals:

1. an acetabular cup; 2. a wing plate; 3. and (6) nailing.

Detailed Description

In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

The invention provides an integrated acetabulum revision prosthesis based on 3D printing, wherein a 3D printed acetabulum is in the shape and structure of a bone defect of a pelvis revision part of a patient, and comprises an acetabulum cup and wing plates, wherein the wing plates are integrally formed on the side of the acetabulum cup through the 3D printing technology, nail tracks are processed on the acetabulum cup and the wing plates, and all the nail tracks are not interfered with each other.

The nail passage arranged on the acetabulum cup comprises 3 iliac nail passages and 1 pubis nail passage. And 3 iliac position nail ways are solid nail ways extending downwards from the acetabular cup. Certainly, the number of nail tracks is not limited to the number, the nail track design is determined according to the CT data of the acetabulum defect condition, the screw holding capacity and the rich bone are most favorably realized, the number of the nail tracks is also determined according to the CT data of the acetabulum defect, the aim of lasting stability is achieved, and each patient can be different. Such as: in the first example, there are 3 iliac nail ways and 1 pubic nail way, and in the second example, there are 2 sacroiliac long nails, 1 pubic nail and 1 ischial short nail.

The wing plate on one side of the acetabular cup is an ilium wing plate, and at least 2 ilium wing plate nail channels are arranged on the ilium wing plate.

The integrated acetabular revision prosthesis based on 3D printing further comprises a trabecular bone structure filled between the outer sides of the acetabular cup and the nail path and the acetabulum of the patient. The thickness of the trabecular bone structure on the outer side of the acetabular cup is 1.5mm, and the thickness of the trabecular bone structure on the lateral side of the wing plate is 1.5mm.

(4) And planning and designing the prosthesis according to the positioned acetabular cup and the acetabular defect state, filling the defect, adding wing plates, considering the stress direction, auxiliary support filling and the like, and obtaining the optimized and most matched three-dimensional reconstruction configuration of the acetabular cup prosthesis. Performing preoperative simulation installation on the pelvis revision prosthesis obtained by three-dimensional reconstruction through a computer-aided design technology;

Design and intraoperative care:

the close contact between the acetabulum prosthesis and the host bone is ensured, and the acetabulum prosthesis is stably fixed;

(2) reconstructing the rotation center of the hip joint and recovering the biomechanical environment around the hip joint;

and (4) building the acetabulum position, namely a proper anteversion angle and an abduction angle, so as to avoid postoperative dislocation.

The 3D printing process can enable the surface of the acetabulum revision prosthesis to be designed to form a microporous structure, and the appropriate porosity and pore diameter are favorable for bone growth of an inner plant-bone interface so as to ensure the long-term stability of an implant. The porosity and pore size are set according to the need for bone ingrowth. Pore diameter of porous structure of trabecula: 400-500 microns. Bone trabecula porous structure wire diameter: 400-450 microns. Porosity of trabecular bone porous structure: 68-78 percent.

The technical scheme of the invention is further illustrated by the following specific examples.

Example 1

1. Patient information

Patient A, right acetabular defect, removal, revision, CT picture as shown in figure 1;

2. three-dimensional reconstruction

And (3) considering the condition of the acetabular defect on the right side of the patient, deciding to adopt a 3D printing customized individualized prosthesis solution, and establishing a three-dimensional digital model of the patient by utilizing CT data of the patient as shown in figure 2, wherein the local condition is shown in figure 3.

3. Prosthesis design and provisioning

1. The diameter of the acetabulum of the affected side is measured after the acetabulum of the patient is deformed and CT has artifacts and data are conservatively processed, as shown in figure 4.

2. According to the results of the acetabulum measuring machine and the defect condition, an integrated acetabulum prosthesis is designed, the outer diameter of a 58-type acetabular cup 50# acetabular cup is selected as a base to be designed according to the measuring results, the inner diameter of the acetabular cup is 39, a 58-type liner 48# acetabular cup is adapted, and a 32 ball head is adapted. The simulated placement position of the mortar is shown in fig. 5, and the upper left-upper right drawing and the lower left-lower right drawing in fig. 5 are views at four different angles.

In the simulation, the acetabulum angle of the simulated position is shown in fig. 6, because the patient has scoliosis, the deviation of pelvises on two sides is large, the pelvis is moderately corrected (fig. 6A), the abduction angle is about 43.5 degrees (fig. 6B), the anteversion angle is about 16.5 degrees (fig. 6C), and the actual angle parameters in the standard acetabular cup operation are automatically adjusted by a doctor.

3. The prosthesis design is carried out according to the shape of the acetabulum defect, considering force transmission and support, upward movement due to acetabulum deformation, and considering the conditions of intraoperative loading and postoperative prosthesis bone ingrowth: including acetabular cup 1 and pterygoid lamina 2, the pterygoid lamina passes through 3D printing technique integrated into one piece in acetabular cup's side, all processes nail way 3 on acetabular cup and the pterygoid lamina, and all nail ways mutually noninterfere. The wing plate on one side of the acetabular cup is an ilium wing plate, the wing plate on the other side of the acetabular cup is an ischium wing plate, 2 ilium wing plate nail channels are arranged on the ilium wing plate, and 2 ischium wing plate nail channels are arranged on the ischium wing plate. Except the mortar cup, the nail channel and the wing plate which are solid, the prosthesis is of a bone trabecula structure. The flange portion trabecular bone 1.5mm. The bone trabecula of the cup body is 1.5mm, and the filling cushion blocks except the solid nail path are all in a bone trabecula structure. The prosthesis design is shown in fig. 7, where fig. 7A is a front view, fig. 7B is a rear view, fig. 7C is a top view, fig. 7D is a bottom view, and fig. 7E is a perspective view of the rear view.

4. Nail holes are provided in the patient's pelvis to enhance the fixation of the prosthesis, as shown in fig. 8 and 9.

Table 1 shows the maximum length of the proposed nail (measured from the provided CT data for pelvic length).

TABLE 1

Nail position	Length (mm)
		Ilium position No. 1 nail	85
Ilium position No. 2 nail	80
		Ilium orientation No. 3 nail	70
Ilium wing plate No. 4 nail	26
		Ilium wing plate No. 5 nail	20
No. 6 nail for pubic azimuth	35
		Ischial wing plate No. 7 nail	29
Ischial wing plate No. 8 nail	34

Example 2

1. Patient information

Patient B, left acetabular defect, revision, CT image see FIG. 10.

2. Three-dimensional reconstruction

The acetabulum defect on the left side of the patient is considered, a 3D printing customized individualized prosthesis solution is adopted, and a three-dimensional digital model of the patient is established by utilizing CT data of the patient as shown in the following figure 11, and the local condition is shown in figure 12.

3. Prosthesis design and provisioning

1. The acetabulum of the left side of the patient is defective, the rotation center is upward, the defect range is large, the acetabulum is worn through (and the bone of the anterior wall and the upper wall of the acetabulum is seriously defective and is communicated with the pelvic cavity), the surrounding defect with large defect is formed, and the diameter of the position of the affected acetabulum is measured as shown in fig. 13.

2. And designing an integrated acetabular prosthesis according to the result of the acetabular measuring machine and the defect condition, wherein the outer diameter of the 58 model acetabular cup 58# cup is selected as a base to be designed according to the measuring result, the inner diameter of the cup is 44, the liner is matched with the 58 model cup 52# and the head is matched with the cup 36. The simulated placement position of the mortar cup is shown in fig. 14, and the upper left-upper right drawing and the lower left-lower right drawing in fig. 14 are views at four different angles. The acetabulum angle in the simulated position is shown in fig. 15, with an abduction angle of about 42 ° (upper view in fig. 15). Anteversion is about 20 degrees (lower picture in figure 15), and actual angle parameters in the standard acetabular cup are self-adjusted by a doctor.

3. The prosthesis is designed with consideration of force transmission and support according to its defect morphology. Because the acetabulum is worn through from the front to the top, the upper ear plate is designed to prevent the acetabulum from sinking, and the fixation is enhanced. Except the mortar cup and the nail path, the remaining parts of the prosthesis are all bone trabecula structures except the ear plate which is a solid body. The prosthesis design is shown in fig. 16, where fig. 16A is a front view and fig. 16B is a perspective view.

4. Tack holes are provided to enhance the fixation of the prosthesis, as shown in fig. 17 and 18.

In fig. 18, no. 1-4 ilium wing plate short nails, no. 5-6 sacroiliac joint long nails, no. 7 pubic direction nails, no. 8 ischial direction short nails, and common titanium nails with length less than 35 are used and are not provided with prosthesis. The longest reference length for each pin number will be measured after the prosthesis structure is confirmed.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. The utility model provides an integral type acetabular bone revision prosthesis based on 3D prints which characterized in that, includes acetabular cup and pterygoid lamina, the pterygoid lamina passes through 3D printing technique integrated into one piece in acetabular cup's side, all processing has the nail way on acetabular cup and the pterygoid lamina, and all nail ways mutually noninterfere.

2. The 3D printing-based integrated acetabular revision prosthesis of claim 1, wherein the nail way provided on the acetabular cup comprises 3 iliac nail ways and 1 pubic nail way.

3. The 3D printing-based integrated acetabular revision prosthesis according to claim 1, characterized in that a wing plate on one side of the acetabular cup is an iliac wing plate, and at least 2 iliac wing plate nail ways are arranged on the iliac wing plate.

4. The 3D printing based integrated acetabular revision prosthesis of claim 1, further comprising a trabecular bone structure that fills between the outer side of the acetabular cup and nail track and the patient's acetabulum.

5. The 3D printing based integrated acetabular revision prosthesis of claim 4, wherein a thickness of a trabecular structure outside the acetabular cup is 1.5mm and a thickness of a trabecular structure lateral to the wing plate is 1.5mm.

6. The 3D printing based integrated acetabular revision prosthesis of claim 2, wherein the iliac orientation nail track is a solid nail track extending downward from an acetabular cup.

7. A method for preparing the 3D printing-based integrated acetabular revision prosthesis according to any one of claims 1-6, comprising the steps of:

(5) According to the affected side acetabulum defect form, the force transmission and the support are considered, and meanwhile, the integrated acetabulum revision prosthesis design is carried out by considering the intraoperative implantation and the postoperative prosthesis bone growth conditions: the integrated acetabulum revision prosthesis comprises an acetabulum cup and wing plates, wherein the wing plates are integrally formed at the side of the acetabulum cup, and nail tracks are processed on the acetabulum cup and the wing plates; the integral acetabulum revision prosthesis comprises an acetabulum cup, a nail channel and wing plates which are solid, and the rest of the wing plates are all bone trabecula structures; the thickness of the trabecular bone of the wing plate part is 1.5mm, the thickness of the trabecular bone of the cup body is 1.5mm, and the filling cushion blocks except the solid nail path are all in a trabecular bone structure;

8. The method of claim 7, wherein the acetabular cup, wing plate and nail track are of titanium alloy material.