CN107157579A - A kind of pedicle screw is implanted into paths planning method - Google Patents

Abstract

The invention relates to the medical field, in particular to a path planning method for spinal pedicle screw implantation. The method includes the following steps: S1. Preoperative planning: Preprocessing the CT image data of the preoperative patient, performing surgical path planning in the 3D planning system for spinal pedicle screw implantation according to the anatomical characteristics of the spinal pedicle screw implantation to determine the optimal Optimum implantation path; S2. Adjust the 3D posture of the spine in the 3D planning system for spinal pedicle screw implantation, and intercept the simulated axial images of the left and right pedicle screws; S3. Acquisition of the standard axial images during the operation: using the spinal arch The root screw is implanted into the 2D navigation system, and the X-Ray axial map of the spine is obtained during the operation by adjusting the C-arm; S4. Confirmation of the pedicle screw implantation path during the operation: the 2D navigation system is implanted in the spinal pedicle screw In this procedure, the pedicle screw simulation axial image derived from the 3D planning system was registered with the intraoperative X-Ray axial image to determine the implantation point of the spinal pedicle screw. This method can quickly and accurately determine the position of the implantation point of the pedicle screw, reducing the influence of human factors.

Description

A method for path planning of spinal pedicle screw implantation

technical field

The invention relates to the medical field, in particular to a path planning method for spinal pedicle screw implantation.

Background technique

Pedicle screw technology is widely used in spinal surgery due to its biomechanical superiority in three-column fixation. However, conventional open pedicle fixation and fusion surgery requires extensive stripping and long-term stretching of the paraspinal muscles, which often leads to denervation and atrophy of the paraspinal muscles, resulting in the occurrence of spinal fusion disease. In recent years, with the advancement of modern medical science and technology, while striving for the safety and accuracy of pedicle screw implantation, people have also explored the use of minimally invasive means to implant pedicle screws percutaneously, thereby effectively reducing artificial injuries . Since the emergence of percutaneous pedicle screw technology avoids the disadvantages of large incision, multiple muscle stripping, and slow postoperative recovery in traditional posterior spinal internal fixation surgery, it has gradually become the basic technical means of minimally invasive spinal surgery. one.

Due to the stenosis of the pedicle, once the screw passes through the side wall of the pedicle, the operation will fail. The key to the success of transpedicular internal fixation is whether the screw can accurately reach the vertebral body through the pedicle. Therefore, it is very important to correctly find the pedicle landmark from the posterior approach to determine the entry point of the screw and the direction of the needle. In the actual operation, doctors rely on experience and refer to the anatomical points of the spine in X-ray images to perform freehand implantation. At present, the failure rate of the operation is as high as 30%.

The most ideal surgical path is to use the principle of pedicle standard axis positioning, which is to make the axis of the pedicle overlap with the emission axis of the C-arm X-ray machine as much as possible, so as to ensure that the surgical implantation path is parallel to the axis of the pedicle. The best path for pedicle implantation can be obtained by the central position of the oval cat's eye of the pedicle. Patent CN104224306A provides a method of using three-dimensional modeling to find the best entry point of pedicle screws, which can assist doctors to complete surgical path planning before surgery. However, in actual surgery, the determination of the pedicle screw implantation point is generally based on experience and artificial selection, which cannot guarantee that the actual surgical path is consistent with the planned path.

Due to the influence of subjective factors, the positions selected by users in actual operations are different. The accuracy of the selected position seriously affects the implantation effect of the pedicle screw, and improper selection may even cause the screw to pass through the side wall of the pedicle, resulting in failure of the operation. How to scientifically, rationally and accurately find the position of the screw implantation point will be particularly important in the process of pedicle screw implantation.

Contents of the invention

(1) Technical problems to be solved

The purpose of the present invention is to provide a spinal pedicle screw implantation path planning method, which can quickly and accurately find the screw implantation point in the standard axial map of the spinal pedicle.

(2) Technical solution

In order to achieve the above object, the present invention provides a method for planning the path of spinal pedicle screw implantation, as shown in Figure 1, including the following steps: S1, preoperative planning: performing segmentation processing and three-dimensional reconstruction of preoperative patient CT image data , according to the anatomical characteristics of the spinal pedicle screw implantation 3D planning system in the spinal pedicle screw implantation 3D planning system to determine the optimal implantation path; S3, obtain the standard axial image during operation: use the spinal pedicle screw to implant the 2D navigation system, and obtain the X-Ray axis of the spine during operation by adjusting the C-arm Bitmap; S4. Intraoperative pedicle screw implantation path confirmation: In the spinal pedicle screw implantation 2D navigation system, the pedicle screw simulation axis map exported by the 3D planning system and the intraoperative X-Ray axis The bitmap was registered to determine the implantation point of the spinal pedicle screw.

According to the present invention, the axial pedicle diagram of the spine refers to the projected image when two rings formed by the edge projections of the front and rear surfaces of the pedicle shaft overlap on the projected image.

According to the present invention, in step S1, preprocessing the preoperative CT image data of the patient includes: performing segmentation and three-dimensional reconstruction on the preoperative CT image, and the CT data imported into the 3D planning system for spinal pedicle screw implantation includes: DICOM data and segmented STL data.

According to the present invention, in step S1, the anatomical characteristics of the described spinal pedicle:

1) Including the left and right key points of the spine and the left and right end points of pedicle screw implantation;

2) The selection of the left and right key points and the left and right end points is determined by the intersection points of the three planes of X, Y, and Z (respectively red, green, and blue, as shown in Figure 2);

3) The key point is located at the center of the pedicle, the red line is located at the center of the left pedicle (lower right cross-sectional view in Figure 4), the blue line is located at the center of the pedicle (upper right lateral view), and the blue line is located at the center of the panda At the center of the eye (orthographic view at the bottom left of Figure 4);

4) The end point is located at 1/3 of the vertebral body, as shown on the right side of Figure 5.

According to the present invention, in step S2, the spinal pedicle screw implantation 3D planning system can generate a simulated standard axial map (as shown in Figure 9 ) according to the planned left and right pedicle screw implantation paths, and save it .

According to the present invention, in step S3, the spinal pedicle screw implantation 2D navigation system can calculate the adjustment amount of the C arm according to the captured X-ray image and the characteristic data of the spine, so that after the adjustment of the C arm, it can be obtained Standard X-ray axis map (as shown in Figure 10).

According to the present invention, in step S4, the 2D navigation system for spinal pedicle screw implantation can import X-ray images and simulated axial maps derived from 3D software, and the navigation system can translate, rotate, and zoom the left and right standard axial maps , to realize the overlay registration of the axis map and the X-ray map.

According to the present invention, in step S4, after the axial image and the X-ray image are superimposed and registered, the center position of the nail in the axial image is selected as the screw implantation point (as shown in FIG. 12 ).

(3) Beneficial effects

The path planning method for spinal pedicle screw implantation of the present invention can scientifically and reasonably plan the path of pedicle screw implantation, and reduce the location of path points when pedicle screw implantation is heavily dependent on the doctor's experience and subjectivity , prone to problems such as deviation, improve the safety of the operation, and then reduce the number of radiation to the patient, reduce the harm, shorten the operation time, and reduce the medical cost.

Description of drawings

Figure 1 is a flowchart of the implementation of the path planning method for spinal pedicle screw implantation

Figure 2 is a schematic diagram of the 3D planning system software for spinal pedicle screw implantation

Figure 3 is the planning spine segment selection

Figure 4 is the planning left key point

Figure 5 is the planning left end point

Figure 6 is the effect diagram of the planned path of the left pedicle screw

Figure 7 is a 3D diagram of the planned path of the left pedicle screw at different angles

Figure 8 is the effect diagram of the planned path of the right pedicle screw

Figure 9 is the simulated axial map obtained in the 3D software (A is the right side, B is the left side)

Figure 10 is the X-ray axial view taken during the operation

Figure 11 is the registration result of the simulated axis map and the X-ray axis map

Figure 12 is the screw position and implantation point during the operation

detailed description

The present invention will be further described in detail below in conjunction with the accompanying drawings.

Referring to FIG. 1 , a specific embodiment of the present invention includes steps S1 to S4. The specific implementation is as follows:

Step S1 preoperative planning:

Step S1.1: Use MIMICS or other medical image processing software to segment and process the patient's preoperative CT data to obtain the patient's spinal bone surface, and conduct 3D reconstruction to export the STL model.

Step S1.2: Import the patient's DICOM data and segmented STL data into the 3D planning system software for spinal pedicle screw implantation.

As shown in Figure 2, the upper left is a 3D diagram, the upper right is a lateral view (sagittal plane), the lower left is a front view (coronal plane), and the lower right is a (transverse section); by adjusting X, Y, The position and rotation of the Z plane (shown in red, green, and blue, respectively) adjusts the position, rotation, and size of the spine in the three views.

Step S1.3: As shown in Figure 3, adjust the three views of the spine, correct the image of the spine, and adjust the planning line so that it is located on the current spine joint.

Step S1.4: Planning the implantation path of the left pedicle screw.

Step S1.4.1: Plan the left key point, adjust the red line to be located at the center of the left pedicle (as shown in the lower right cross-sectional view of Figure 4), and the blue line to be located at the center of the pedicle (as shown in the upper right lateral view of Figure 4), The blue line is located at the center of the panda's eye (as shown in the lower left orthographic image of Figure 4), and the intersection of the three planes is the left key point;

Step S1.4.2: Plan the left end point, adjust the green planning line to 1/3 of the vertebral body (as shown in the right diagram in Figure 5), and the intersection of the three planes is the left end point.

As shown in Figure 6, after completing the planning of the left key point and the left end point, plan the path effect.

As shown in Fig. 7, the surgical path planning effect in the 3D diagram under different angles.

Step S1.5: Refer to step S1.4.1 and step S1.4.2 to plan the implantation path of the right pedicle screw, and the planning effect is shown in Figure 8.

Step S2: adjust the posture of the spine, and project along the planned left and right paths of the spinal pedicle respectively to obtain a standard axial view of the left and right pedicle screws (as shown in FIG. 9 ), and save it.

Step S3: Obtain the intraoperative X-Ray axial map: According to the feature points of the spine during the operation, the C-arm adjustment parameters are calculated through the 2D navigation system, and the C-arm pose is adjusted until the right standard axial map of the spine is obtained. On the X-Ray image, the two rings formed by the edge projections of the front and rear surfaces of the pedicle shaft coincide (as shown in Figure 10).

Step S4: Determine the pedicle screw insertion point:

Step S4.1: importing the simulated standard right axial view shown in Fig. 6A into the 2D navigation system for spinal pedicle screw implantation;

Step S4.2: By translating, rotating, and scaling the simulated standard right-axis bitmap, superimposing and registering with the X-ray standard right-axis bitmap, so that the contours of the spine coincide (as shown in Figure 11);

Step S4.3: Select the position center of the screw in the simulated standard right axial view as the screw implantation point on the right side of the spine (as shown in Figure 12);

Step S4.4: According to the screw implantation point on the right side of the spine as shown in Figure 12, insert the pedicle screw on the right side of the spine according to the guidance of the navigation system.

Step S4.5: Repeat steps S3, S4.1-S4.4, implant the left pedicle screw of the spine.

Claims (7)

1. a kind of pedicle screw is implanted into paths planning method, it is characterised in that comprise the following steps：

S1, preoperative planning, are pre-processed to pre-operative patients CT image datas, according to the anatomical features of vertebral arch pedicle of vertebral column point in ridge Operation pathway planning is carried out in post pedicle screw implantation 3D planning systems and determines optimal implantation path；

S2, the adjustment backbone 3D poses in pedicle screw implantation 3D planning systems, interception left and right pedicle screw simulation Axle position figure；

S3, art Plays axle position figure are obtained, and 2D navigation system is implanted into using pedicle screw, by adjusting C-arm, are obtained The X-Ray axle position figures of backbone in art；

Pedicle screw implantation path confirms in S4, art, and in pedicle screw implantation 2D navigation system, 3D is planned into system The derived pedicle screw simulation axle position figure of system is registering with X-Ray axle positions figure progress in art, determines that pedicle screw is implanted into Point.

2. according to claim 1, a kind of pedicle screw is implanted into paths planning method, it is characterised in that described in step S4 Art in pedicle screw implantation path confirmation method, comprise the following steps：

S4.1 by preoperative 3D planning systems simulation axle position figure by being translated, being rotated, scaled, with the X-Ray axle position figures in art Carry out registration so that preoperative simulation axle position figure is overlapping with the X-Ray axle position figure backbone profiles in art；

S4.2 regard the center that simulation nail in axle position figure is simulated after registration as pedicle screw implantation point in art.

3. according to claim 1, a kind of pedicle screw is implanted into paths planning method, it is characterised in that described axle position Figure refers on projection images, perspective view when two annulus that the edge projections of pedicle of vertebral arch axle front and rear surfaces is formed are overlapped Picture.

4. according to claim 1, a kind of pedicle screw is implanted into paths planning method, it is characterised in that described in step S1 Vertebral arch pedicle of vertebral column anatomical features including backbone left and right key point and the left and right terminal of pedicle screw implantation：

Described key point is in pedicle of vertebral arch center；

Described terminal is located at the 1/3 of centrum.

5. according to claim 1, a kind of pedicle screw is implanted into paths planning method, it is characterised in that described in step S1 Pre-operative patients CT image datas are pre-processed, including：Preoperative CT images are split and three-dimensional reconstruction.

6. according to claim 1, a kind of pedicle screw is implanted into paths planning method, it is characterised in that described step The CT data that S1 is imported into pedicle screw implantation 3D planning systems include DICOM data and the STL data split.

7. according to claim 1, a kind of pedicle screw is implanted into paths planning method, it is characterised in that step 3 is step C-arm must be adjusted by 2D navigation system first in 4 precondition, art, get the X-Ray axle position figures of backbone in art.