3D printing puncture guide plate for vertebral compression fracture and positioning method of 3D printing puncture guide plate

Abstract

The invention provides a 3D printed centrum compression fracture puncture guide plate, and aims to improve the positioning accuracy, the operation efficiency and the safety of percutaneous vertebroplasty (PVP). A traditional guide plate has the problems of inaccurate positioning, easy dislocation of the guide plate and the like in clinical application, especially under the condition that the back skin sliding performance is strong and no obvious positioning mark exists. In order to solve the problems, the bowstring shaping theory and the modularized guide plate are creatively applied, the specific bending form of the spine in the operation process is ensured, the situation that the position of the guide plate is inaccurate due to skin sliding is avoided, and therefore the puncture path is ensured.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing and applying spinal surgery tools, and in particular to a 3D printed puncture guide plate for precise spinal positioning and a positioning method thereof. Background Art

[0002] Vertebral compression fractures (especially osteoporotic thoracolumbar compression fractures) are common spinal diseases in elderly patients, mainly manifested as severe low back pain and dysfunction, which seriously affects the quality of life of patients. With the aging of the population, the incidence of such diseases has increased year by year, bringing great pressure to patients and the medical system. Percutaneous vertebroplasty (PVP), as a minimally invasive treatment method, has been widely used in the treatment of vertebral compression fractures, with the significant advantages of quickly relieving patients' pain and restoring vertebral stability.

[0003] However, existing PVP surgical methods usually rely on the surgeon's experience for puncture positioning, and C-arm X-ray fluoroscopy is frequently used during the operation to confirm the position of the puncture needle. Although X-ray fluoroscopy can provide real-time images, long-term reliance on X-ray fluoroscopy will not only increase the radiation exposure of patients and medical staff, but also prolong the operation time and increase the complexity of the operation, thereby affecting the safety and effectiveness of the operation.

[0004] In order to improve the accuracy and safety of PVP surgery, 3D printing technology has been gradually introduced into minimally invasive surgery in recent years, especially in the design of customized puncture guides. Through personalized reconstruction of preoperative imaging data, 3D printed guides can be customized according to the patient's anatomical structure, assist in precise positioning during surgery, reduce the number of intraoperative fluoroscopy, and improve the accuracy of the puncture needle path.

[0005] However, the existing 3D printed guides still have some problems in practical applications, which are mainly manifested in the following aspects: 1. Unclear body surface landmarks: Existing guide designs usually rely on body surface landmarks to determine the puncture path. However, since there are no obvious bone landmarks on the skin surface of the patient's waist and back, and the skin surface may be affected by body shape differences, the body surface landmarks are unclear, which affects the positioning accuracy of the guide; 2. Skin elastic sliding: The time difference and body position difference between the CT data obtained before the operation and the actual operation during the operation may cause the patient's skin to slide due to elastic deformation or movement, which is different from the CT modeling data, causing the guide to shift on the body surface, affecting the accuracy of the puncture path; 3. Complex guide structure: Existing guide designs are usually complex, resulting in a cumbersome manufacturing process for the guide and a long printing time, which is not conducive to the implementation of efficient clinical surgery and is difficult to meet clinical needs for surgical efficiency and safety.

[0006] In order to solve the above problems, the present invention proposes an innovative positioning method based on the bowstring shaping theory, which avoids the problem of guide displacement caused by skin sliding. This innovative application significantly improves the stability of the puncture guide, ensures the accuracy of the puncture path, and thus reduces the use of intraoperative fluoroscopy, reduces radiation exposure, and improves surgical safety. In the application of the electrode buckle module, the optimized design of the guide structure, and the puncture needle buckle module, the efficiency of guide modeling and 3D printing is further improved by adopting prefabricated modular design and simplified structural design. Summary of the invention

[0007] The present invention provides a 3D printed puncture guide for vertebral compression fractures, aiming to solve the problems of unstable guide positioning, complex modeling process, long model printing time, long operation time, high radiation exposure, etc. in the prior art. Through innovative design, the present invention significantly shortens the modeling time and 3D printing time, improves the accuracy, safety and efficiency of the operation. And through the bowstring shaping theory, the problem of difficult guide positioning caused by back skin sliding is effectively solved.

[0008] The 3D printed puncture guide and its application method of the present invention include the following key contents:

[0009] Application of bowstring shaping theory: The physiological curvature of the spine is the bow body, and the straight-line distance between the designated protrusions on the back and sacrum is the bowstring ( Figure 11-12 ). Before the operation, when the patient is in the prone position for CT scanning, ordinary medical electrodes are attached to the raised parts of the back and sacrum and coccyx. The distance between the electrodes attached to the back and sacrum is measured and recorded as the bowstring length. The CT scan data is modeled and the puncture path is planned using a computer, and the puncture guide is made by 3D printing. During the operation, the patient lies prone on the operating table, and the folding knife pitch angle of the operating table is precisely adjusted (the angle of the V-shaped or Λ-shaped lying position of the operating table) to make the distance (chord length) between the back and sacrum electrodes consistent with the distance measured during the preoperative CT scan, thereby keeping the spinal curvature angle (bow body) consistent with the model built by the computer, ensuring consistent skin tension, avoiding inaccurate guide positioning caused by skin sliding, and ensuring the accuracy of the puncture path.

[0010] Electrode snap-on module: This module is equipped with slots and cavities, which can accurately match the patient's body surface electrode and fix the guide plate. The bottom of the model has a stretchable design, which is stretched to a suitable length during modeling to adapt to the body surface characteristics of different patients. After 3D printing, the guide plate is stably fixed, thereby improving the accuracy of the puncture path.

[0011] Puncture needle buckle module: It adopts an open structure and a stretchable bottom surface. After 3D printing, it is easy to quickly disassemble or adjust the puncture path during surgery, improving surgical flexibility and safety.

[0012] Guide plate structure optimization: When modeling the guide plate, stretch the bottom surfaces of the electrode buckle module and the puncture needle buckle module to a unified plane, and use a simple connecting plate to stretch and connect all the buckle modules. Simplify the guide plate structure, reduce redundant shapes, improve 3D printing efficiency, and facilitate rapid production and clinical application.

[0013] The 3D printed puncture guide is widely applicable to minimally invasive surgery for vertebral compression fractures, and can be extended to other surgical operations that lack surface landmarks and require precise positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1-3 This is the three-view drawing of the electrode clip module; Figure 4 It is a cross-sectional view of the electrode sheet buckle module; Figure 5 This is an oblique view of the puncture needle buckle; Figure 6 For the colored graph; Figure 7-9 It is the application schematic diagram; Fig.10 Real photos of the application; Fig.11 A schematic diagram for shaping the bowstring; Fig.12 Actual photos of the bowstring being shaped.

[0015] In the figure: 1. electrode sheet; 2. electrode sheet buckle module; 21. electrode sheet buckle bottom surface; 22. electrode sheet buckle module slot; 23. electrode sheet buckle cavity; 3. puncture needle buckle module; 31. puncture needle buckle bottom surface; 4. fractured vertebra; 5. skin; 6. puncture needle; 7. connecting plate. DETAILED DESCRIPTION

[0016] Example: Application of 3D printed puncture guide

[0017] Preoperative preparation and guide design First, the patient lies prone on the CT examination bed before the operation, and two ordinary medical electrodes are attached to the skin around the injured vertebra, and one ordinary medical electrode is attached to the highest part of the back and sacrum. The bowstring length is measured and recorded. The patient lies prone and a CT scan is used to obtain the imaging data of the lumbar fracture area of ​​the patient. The CT scan data (DICOM) is calculated by a computer to generate a three-dimensional model of the fractured vertebra, electrode and skin, and the puncture path is designed and imported into the 3D modeling software.

[0018] Move the pre-designed electrode clip module to the electrode position of the 3D model, and design at least 3 electrode clips to ensure spatial positioning consistency ( Figure 7 ), move the puncture needle buckle module to the puncture needle position. Stretch the bottom surface of the electrode buckle module and the bottom surface of the puncture needle buckle to the same height plane.

[0019] Use a simple connection plate to connect the electrode clip module and the puncture needle clip module at the same plane above the skin ( Figure 8-9 ).

[0020] After the guide plate design is completed, it is imported into the slicing software, sliced ​​and FDM 3D printed.

[0021] The printing process uses modular design to reduce redundant structures, so that the printing time of the guide plate is controlled within 30 minutes, meeting the high-efficiency needs of clinical surgery.

[0022] Intraoperative use: The patient lies prone on the operating table. By adjusting the pitch angle of the folding knife on the operating table, the bowstring length of the back and sacral electrode pads is measured ( Fig.12 ), so that the body position is the same as that during the preoperative CT scan, ensure that the relative position of the skin and vertebral body is stable, and the electrodes on the waist and back are disinfected together with the skin. After the guide is disinfected, it is fixed to the patient's body surface electrode through the electrode clip module to ensure that the guide does not shift. The puncture needle performs puncture according to the guidance of the guide. After the puncture operation is completed, the guide is removed and the C-arm fluoroscopy is used for conventional bone cement injection. The design of the guide not only reduces the operation time, but also improves the accuracy of the operation and avoids excessive X-ray fluoroscopy.

[0023] Summary: This embodiment demonstrates the application of the 3D printed puncture guide of the present invention in minimally invasive surgery for vertebral compression fractures. Through the bowstring shaping theory method, the problem of inaccurate guide positioning caused by back skin tension and sliding is effectively solved. The innovative design of the electrode buckle module and the puncture needle buckle module enables the guide to be stably fixed on the patient's body surface, ensuring accurate guidance of the puncture path, improving modeling and 3D printing efficiency, improving surgical efficiency, and reducing intraoperative radiation exposure.

[0024] In order to determine the technical effect of the present invention, a surgical comparison verification was performed: This study included 120 patients with thoracolumbar compression fractures who underwent percutaneous vertebroplasty in our hospital. All patients met the inclusion and exclusion criteria. The patients were divided into a freehand group (60 patients) and a guided plate group (60 patients). In the freehand group, there were 25 male patients and 35 female patients; in the guided plate group, there were 26 male patients and 34 female patients. The age range of the patients was 60 to 82 years old, with an average age of (68.4 ± 6.5) years old. There were no significant differences in gender, age, body mass index (BMI) and fracture segment distribution between the two groups (P>0.05).

[0025] All patients were randomly divided into two groups according to the surgical method: freehand group and guide plate group. The freehand group was treated by experienced senior orthopedic chief physicians using traditional C-arm fluoroscopic percutaneous vertebroplasty, while the guide plate group was assisted by a puncture guide based on skin fixed point anchoring and designed with 3D printing technology on the basis of traditional surgery. There were 60 patients in each group. The Japanese Orthopedic Association (JOA) score, visual analog scale (VAS) score and Oswestry disability index (ODI) were used to evaluate the preoperative pain level and spinal function score of the two groups before, 1 week and 12 weeks after surgery. The change of vertebral anterior edge height, sagittal index (SI) and Cobb angle were used to evaluate the recovery of vertebral height.

[0026] Statistical analysis showed that the operation time, puncture time and number of X-ray fluoroscopy in the guide plate group were significantly shorter or reduced compared with those in the freehand group (P<0.05). The vertebral anterior height, vertebral sagittal index and Cobb angle in both groups before and 1 week after surgery were significantly improved 1 week after surgery compared with those before surgery (P<0.05), indicating that the fracture reduction and kyphosis correction effects were good; there was no significant difference between the two groups at the same time point (P>0.05). The postoperative pain level of both groups was significantly improved compared with that before surgery, and the JOA score increased significantly and the ODI decreased significantly at 1 week and 12 weeks after surgery (P<0.05); there was no significant difference between the two groups at the same time point (P>0.05).

[0027] The results showed that compared with the traditional freehand puncture group, the patented method can significantly shorten the operation time, reduce the number of intraoperative fluoroscopy times and puncture time. At the same time, there was no significant difference in the incidence of postoperative complications between the two groups of patients.

Claims

1. A method for applying the bowstring shaping theory of a 3D printed puncture guide for vertebral compression fractures, the method comprising the following steps: When the patient was in the prone position before surgery for CT scanning, the distances between the back and designated locations of the sacrum and coccyx were measured; Using computer modeling technology, we perform three-dimensional modeling, plan the puncture path, and design modular 3D printed puncture guides based on preoperative CT scan data; During the operation, the patient lies prone on the operating table, and the pitch angle of the operating table folding knife is adjusted to make the distance measured at the designated position of the back and sacrum consistent with that of the preoperative CT scan; A 3D-printed modular puncture guide is used to guide the puncture needle to complete the surgery.

2. The modular puncture guide according to claim 1, characterized in that: The electrode clip module, puncture needle clip module, and guide plate overall structure are optimized.

3. The electrode sheet buckle module as claimed in claim 2 is provided with a slot, a cavity and a bottom surface for stretching during modeling.

4. The puncture needle buckle module as described in claim 2 is provided with a side slot and a bottom surface for stretching during modeling.

5. The overall structure of the guide plate as described in claim 2 is optimized, and a unified plane connecting plate design is used to connect all the buckle modules.

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