A spinal displacement positioning method and system for orthopedic surgical navigation

Abstract

The application provides a spinal displacement positioning method and system for orthopedic surgery navigation, which comprises the following steps: acquiring a first point cloud image and a second point cloud image corresponding to a non-healthy spinal segment of a human body for orthopedic surgery navigation and calculating a conversion matrix; acquiring ultrasonic images of each healthy spinal segment of the human body corresponding to a fixed reference frame through an ultrasonic detection module on each fixed reference frame; mapping the ultrasonic images into the first point cloud image or the second point cloud image through the conversion matrix to acquire position coordinates of each healthy spinal segment of the human body corresponding to the fixed reference frame; monitoring each position coordinate in real time and alarming and recording a change value when the position coordinate changes; and positioning the non-healthy spinal segment of the human body with displacement through the change value. The scheme can realize accurate positioning of the displacement of the non-healthy spinal segment in orthopedic surgery navigation, thereby avoiding deviation in surgery.

Description

Technical Field

[0001] This invention relates to the field of orthopedic surgical navigation technology, and more particularly to a spinal displacement positioning method and system for orthopedic surgical navigation. Background Technology

[0002] Surgical navigation is widely used in surgical localization in spinal surgery, trauma orthopedics, joint replacement, and neurosurgery because it can accurately guide surgical positioning during surgery. Most existing orthopedic surgical navigation systems are based on CT data to construct three-dimensional spatial images, using binocular positioning devices and fixed reference frames attached to the patient's body to achieve real-time tool tracking.

[0003] However, for multi-segment orthopedic surgical navigation, such as for the spine, the human spine is composed of vertebral segments with non-rigid connections. In spinal navigation surgery, a fixed reference frame is attached to a healthy spinal segment, while surgical manipulation is performed on an unhealthy segment. Due to the non-rigid spinal connections, it's easy for the healthy segment with the fixed reference frame to experience only minor displacement, while the unhealthy segment undergoing surgery may experience significant displacement due to external forces. This displacement is often undetectable by the binocular positioning equipment using the fixed reference frame, leading to surgical errors. Therefore, there is an urgent need for a method that can accurately locate the displacement of unhealthy spinal segments during orthopedic surgical navigation. Summary of the Invention

[0004] The purpose of this invention is to provide a spinal displacement positioning method and system for orthopedic surgical navigation, which enables precise positioning of the displacement of unhealthy spinal segments during orthopedic surgical navigation, thereby avoiding surgical deviations.

[0005] The technical solution provided by this invention is as follows:

[0006] In a first aspect, the present invention provides a spinal displacement positioning method for orthopedic surgical navigation, comprising a plurality of fixed reference frames, wherein the fixed reference frames are used to conform to the surface of the human skin along the direction of the human spine and correspond to healthy spinal segments, and each fixed reference frame is equipped with an ultrasound detection module, comprising the following steps:

[0007] Acquire a first point cloud image and a second point cloud image corresponding to unhealthy spinal segments of the human body for orthopedic surgical navigation, and calculate the transformation matrix between the first point cloud image and the second point cloud image;

[0008] Ultrasound images of each healthy human spinal segment corresponding to the fixed reference frame are acquired by the ultrasound detection module on each of the fixed reference frames.

[0009] The ultrasound image is mapped to the first point cloud image or the second point cloud image using the transformation matrix to obtain the position coordinates of each healthy human spinal segment corresponding to the fixed reference frame;

[0010] The position coordinates of each healthy human spinal segment corresponding to the fixed reference frame are monitored in real time, and an alarm is triggered and the change value of the position coordinates is recorded when the position coordinates change.

[0011] The displacement of unhealthy spinal segments in the human body is located by using the aforementioned change values.

[0012] This solution enables non-invasive orthopedic surgical navigation by setting up multiple fixed reference frames, which are attached to the skin along the spine and correspond to healthy spinal segments. After acquiring first and second point cloud images corresponding to unhealthy spinal segments for orthopedic surgical navigation and calculating the transformation matrix between them, an ultrasound detection module on the fixed reference frame can acquire ultrasound images of each healthy spinal segment corresponding to the fixed reference frame. The transformation matrix maps the ultrasound images onto the first or second point cloud image, thus obtaining the position coordinates of each healthy spinal segment corresponding to the fixed reference frame. By real-time monitoring of these position coordinates, an alarm is triggered and the change in position coordinates is recorded. Due to the interconnectedness of the spinal segments, the change in healthy spinal segments can pinpoint the displaced unhealthy spinal segment and its degree of displacement. This allows for precise location of unhealthy spinal segments during orthopedic surgical navigation, preventing surgical deviations.

[0013] In some embodiments, locating the displaced unhealthy spinal segment of the human body by means of the change value specifically includes:

[0014] The displacement of the healthy human spinal segment is determined by the change in the position coordinates, as well as the displacement distance and angle of each displacement healthy human spinal segment.

[0015] Interpolation calculations are performed on the displacement distance and angle of each displaced healthy spinal segment to locate the displaced unhealthy spinal segment and its displacement distance and angle.

[0016] In some embodiments, the number of fixed reference frames is two, and they are respectively attached to the skin surface of the healthy spinal segments at both ends of the unhealthy spinal segments.

[0017] In some embodiments, the acquisition of a first point cloud image and a second point cloud image corresponding to unhealthy spinal segments of the human body for orthopedic surgical navigation, and the calculation of a transformation matrix between the first point cloud image and the second point cloud image, specifically includes:

[0018] A first point cloud image of a target region is acquired through a first imaging component. The target region includes the fixed reference frame and a region corresponding to an unhealthy segment of the human spine.

[0019] The second point cloud image of the target area is acquired by the second imaging component, and the first point cloud image and the second point cloud image are registered by the fixed reference frame to obtain the transformation matrix between the first point cloud image and the second point cloud image.

[0020] In some implementations, the first imaging component is a CT scanning component.

[0021] In some embodiments, the second imaging component is a binocular positioning device, and a reflective ball component is installed on each of the fixed reference frames.

[0022] In some embodiments, mapping the ultrasound image to the first point cloud image or the second point cloud image using the transformation matrix further includes:

[0023] The three-dimensional data of the fixed reference frame and the position data of the ultrasonic detection module on the fixed reference frame are acquired, and the mapping of the ultrasonic image is registered using the three-dimensional data and the position data.

[0024] In some embodiments, one side of the fixed reference frame is provided with an adhesive surface for conforming to the surface of human skin, the adhesive surface being an arc surface conforming to the human body's shape and / or an elastic surface.

[0025] In some embodiments, the method further includes: displaying the displacement distance and angle of each displaced healthy spinal segment of the human body through a display module, and displaying the displacement distance and angle of the displaced unhealthy spinal segments of the human body in the first point cloud image or the second point cloud image.

[0026] In a second aspect, this application provides a spinal displacement positioning system for orthopedic surgical navigation, including a processor that stores computer programs or instructions to perform the steps of the spinal displacement positioning method described in the first aspect.

[0027] The spinal displacement positioning method and system for orthopedic surgical navigation provided by this invention can accurately locate the displacement of unhealthy spinal segments during orthopedic surgical navigation, thereby avoiding surgical deviations. Attached Figure Description

[0028] The preferred embodiments will now be described in a clear and easy-to-understand manner, with reference to the accompanying drawings, to further explain the above-mentioned characteristics, technical features, advantages, and implementation methods of this solution.

[0029] Figure 1 This is a schematic diagram of the overall process of one embodiment of the present invention. Detailed Implementation

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without creative effort.

[0031] To keep the drawings concise, only the parts relevant to the invention are shown schematically in each figure, and they do not represent the actual structure of the product. Furthermore, for ease of understanding, in some figures, only one of components with the same structure or function is shown schematically, or only one is labeled. In this document, "one" can mean not only "only one" but also "more than one".

[0032] Surgical navigation is widely used in surgical localization in spinal surgery, trauma orthopedics, joint replacement, and neurosurgery because it can accurately guide surgical positioning during surgery. Most existing orthopedic surgical navigation systems are based on CT data to construct three-dimensional spatial images, using binocular positioning devices and fixed reference frames attached to the patient's body to achieve real-time tool tracking.

[0033] However, for multi-segment orthopedic surgical navigation, such as for the spine, the human spine is composed of vertebral segments with non-rigid connections. In spinal navigation surgery, a fixed reference frame is attached to a healthy spinal segment, while surgical manipulation is performed on an unhealthy segment. Due to the non-rigid spinal connections, it's easy for the healthy segment with the fixed reference frame to experience only minor displacement, while the unhealthy segment undergoing surgery may experience significant displacement due to external forces. This displacement is often undetectable by the binocular positioning equipment using the fixed reference frame, leading to surgical errors. Therefore, there is an urgent need for a method that can accurately locate the displacement of unhealthy spinal segments during orthopedic surgical navigation.

[0034] Considering the interconnectedness between different segments of the human spine, this scheme monitors the displacement and degree of displacement of multiple healthy spinal segments on both sides of an unhealthy spinal segment. This allows for the estimation of displacement in the unhealthy segment and its extent, providing a warning and preventing surgical errors. Furthermore, monitoring of healthy spinal segments is performed using an ultrasound probe combined with a fixed reference frame. This allows for non-invasive fixation of the reference frame while simultaneously monitoring healthy spinal segments, without affecting the acquisition of point cloud images of unhealthy spinal segments. The following is a detailed description of this scheme with reference to the accompanying figures:

[0035] In one embodiment, refer to the appendix to the specification. Figure 1 This invention provides a spinal displacement positioning method for orthopedic surgical navigation, comprising several fixed reference frames. One side of each reference frame has an adhesive surface for conforming to the surface of human skin. The adhesive surface is an arc surface conforming to the human body's shape and / or an elastic surface, allowing the reference frame to adhere tightly to the human skin surface. This application does not limit the size of the fixed reference frames; after being adhered to the human skin surface, each reference frame can correspond to one or more vertebrae of the human spine.

[0036] In existing orthopedic surgical navigation, typically only one fixed reference frame is needed to register multiple point cloud data of unhealthy spinal segments (i.e., the spinal location requiring surgery). This application, however, aims to avoid situations where, due to non-rigid spinal connections, the healthy spinal segments with the fixed reference frame experience minimal displacement, while the unhealthy spinal segments undergoing surgery experience significant displacement due to external forces (such as the surgical procedure). Multiple fixed reference frames are used, attached to the skin surface along the direction of the human spine and corresponding to the healthy spinal segments. Specifically, at least two fixed reference frames are used, each attached to the skin surface of a healthy spinal segment at one end of the unhealthy spinal segment.

[0037] Each fixed reference frame is equipped with an ultrasonic detection module, which includes an ultrasonic probe. The ultrasonic probe is the core component of the ultrasonic imaging system, and its performance directly affects the imaging quality and diagnostic results. The working principle of the ultrasonic probe is based on the piezoelectric effect, mainly including the direct piezoelectric effect and the inverse piezoelectric effect: In the inverse piezoelectric effect, when a high-frequency voltage is applied to a piezoelectric crystal (such as lead zirconate titanate PZT), the crystal will undergo mechanical vibration under the action of the electric field force, thereby generating ultrasonic waves; In the direct piezoelectric effect, when the ultrasonic waves are reflected back to the probe, the piezoelectric crystal converts the mechanical vibration into electrical signals. These signals are transmitted to the ultrasonic host (processor) for processing, and finally form a two-dimensional or three-dimensional image.

[0038] Upon receiving a scanning command, the ultrasound detection module controls the ultrasound probe to generate ultrasound waves and constructs ultrasound images of each healthy spinal segment corresponding to the fixed reference frame based on the reflected echoes. When using devices such as binocular positioning systems in orthopedic surgical navigation systems, a reflective sphere assembly is also installed on the fixed reference frame. This assembly consists of a support and several reflective spheres, typically infrared reflective spheres made of highly reflective materials that reflect specific wavelengths of light (such as infrared light). When acquiring images using devices such as binocular positioning systems, the system is positioned towards the reflective sphere assembly and emits infrared light. The reflective sphere assembly enables registration of the images acquired by the binocular positioning system with images acquired through other means (such as CT images). The infrared reflective sphere may also contain concentric reflective titanium beads. In CT imaging, reflective spheres (such as passive infrared reflective spheres) are mainly used for auxiliary positioning and image registration. These spheres are typically made of highly reflective materials that reflect specific wavelengths of light (such as infrared light). In CT imaging, the primary function of the reflective sphere is as a marker, helping to establish the coordinate relationship between the CT image and the optical positioning system. Specifically, a reflective titanium bead is embedded inside the reflective sphere. This bead does not diffract during CT scans, resulting in a clear CT image. Simultaneously, the reflective titanium bead and the reflective sphere are concentrically positioned, ensuring they have the same three-dimensional coordinates in space. During a CT scan, the target area is scanned to acquire a high-resolution CT image. Image processing techniques determine the three-dimensional position of the reflective titanium bead in the CT coordinate system. Simultaneously, a binocular positioning system acquires the three-dimensional position of the reflective sphere in the optical positioning system. By combining the positions of the reflective sphere in the CT and optical positioning systems, a coordinate transformation matrix is ​​established, thereby achieving precise matching between the CT image and the optical positioning system.

[0039] The spinal displacement localization method of this application includes the following steps:

[0040] S100. Obtain the first point cloud image and the second point cloud image corresponding to the unhealthy spinal segments of the human body for orthopedic surgical navigation, and calculate the transformation matrix between the first point cloud image and the second point cloud image.

[0041] Specifically, a first point cloud image of the target area can be acquired through a first imaging component. The target area includes a fixed reference frame and regions corresponding to unhealthy spinal segments in the human body. A second point cloud image of the target area can be acquired through a second imaging component. This application does not limit the specific types of the first and second imaging components, and they can be selected according to actual conditions. In one specific implementation, the first imaging component is a CT scanning component; the second imaging component is a binocular positioning device.

[0042] A CT scanning assembly includes an X-ray tube for generating an X-ray beam, a detector for receiving the X-ray beam, and a rotating gantry for fixing the X-ray tube and detector. CT (Computed Tomography) imaging is a medical imaging technique that uses X-rays to penetrate the human body or other objects and processes the data to generate tomographic images. The core principle of CT imaging is to utilize the attenuation characteristics of X-rays as they penetrate an object. Detectors collect the attenuated X-ray signals, and computer reconstruction techniques are used to generate tomographic images of the object's interior. The X-ray tube in a CT scanner generates a high-energy X-ray beam. As these X-rays penetrate the human body or other objects, they attenuate to varying degrees due to differences in density and atomic number among different tissues or materials. Materials with high density or high atomic number (such as bone and metal) attenuate X-rays more strongly, while materials with low density (such as air and soft tissue) attenuate less. After penetrating the object, the X-rays are received by a detector array. The detectors convert the X-ray signals into electrical signals, recording the attenuation information at each angle. By rotating the X-ray tube and detectors, data is acquired from multiple angles (usually 360°), forming a set of projection data. Computer algorithms (such as filtered back projection) are used to process the projection data and reconstruct tomographic images of the object's interior. Each tomographic image represents the object's internal structure on a specific plane, and a three-dimensional structure can be reconstructed from multiple tomographic images.

[0043] Binocular positioning devices mimic the principle of human binocular vision, acquiring images of the same scene from different angles using two cameras. They then calculate the depth information of objects using parallax (the positional difference between corresponding points in the two images). The core steps include: image acquisition: two cameras simultaneously acquire images of the same scene; stereo correction: geometrically correcting the acquired images to ensure they are on the same plane; stereo matching: finding corresponding points in the left and right images using algorithms (such as SGBM, BM, etc.); depth calculation: calculating the depth information of objects based on the parallax formula; and 3D reconstruction: reconstructing the 3D structure of the object using the depth information.

[0044] By registering the first point cloud image and the second point cloud image using a fixed reference frame, the transformation matrix between the first point cloud image and the second point cloud image can be obtained.

[0045] S200: Acquire ultrasound images of each healthy human spinal segment corresponding to the fixed reference frame through the ultrasound detection module on each fixed reference frame.

[0046] The ultrasound probe of the ultrasound detection module is set facing the human body surface. During orthopedic surgery navigation, the ultrasound detection modules on each fixed reference frame are controlled by the controller to emit ultrasound waves, and ultrasound images of each healthy spinal segment corresponding to the fixed reference frame can be obtained based on the reflected echoes.

[0047] S300: The ultrasound image is mapped to the first point cloud image or the second point cloud image through a transformation matrix to obtain the position coordinates of each healthy human spinal segment corresponding to the fixed reference frame.

[0048] Since the ultrasound detection module is installed on a fixed reference frame, the ultrasound image can be mapped to the first or second point cloud image through the transformation matrix between the first and second point cloud images, and the position coordinates of each healthy human spinal segment corresponding to the fixed reference frame in the first or second point cloud image can be obtained.

[0049] Meanwhile, since the ultrasonic detection module and the reflective ball assembly on the fixed reference frame have a certain physical positional relationship, in order to improve the mapping accuracy, when mapping the ultrasonic image to the first point cloud image or the second point cloud image through the transformation matrix, it may also include: acquiring the three-dimensional data of the fixed reference frame and the position data of the ultrasonic detection module on the fixed reference frame, and registering the mapping of the ultrasonic image through the three-dimensional data and the position data.

[0050] The S400 monitors the position coordinates of each healthy spinal segment of the human body in real time and corresponds to the fixed reference frame, and alarms and records the change value of the position coordinates when the position coordinates change.

[0051] After obtaining the positional coordinates of each healthy spinal segment corresponding to the fixed reference frame, the positional coordinates of each healthy spinal segment can be monitored in real time. When the human spine is displaced due to external force, the positional coordinates of each healthy spinal segment will also change, triggering an alarm to alert the doctor to the change in spinal position. Simultaneously, the changes in positional coordinates can be recorded.

[0052] S500: Locating displaced, unhealthy spinal segments in the human body by measuring changes in values.

[0053] Specifically, by analyzing the changes in position coordinates, we can determine the displacement of healthy spinal segments in the human body, as well as the displacement distance and angle of each displacement healthy spinal segment. By interpolating the displacement distance and angle of each displacement healthy spinal segment, we can locate the displacement of unhealthy spinal segments in the human body, as well as the displacement distance and angle of each displacement unhealthy spinal segment.

[0054] This solution enables non-invasive orthopedic surgical navigation by setting up multiple fixed reference frames, which are attached to the skin along the spine and correspond to healthy spinal segments. After acquiring first and second point cloud images corresponding to unhealthy spinal segments for orthopedic surgical navigation and calculating the transformation matrix between them, an ultrasound detection module on the fixed reference frame can acquire ultrasound images of each healthy spinal segment corresponding to the fixed reference frame. The transformation matrix maps the ultrasound images onto the first or second point cloud image, thus obtaining the position coordinates of each healthy spinal segment corresponding to the fixed reference frame. By real-time monitoring of these position coordinates, an alarm is triggered and the change in position coordinates is recorded. Due to the interconnectedness of the spinal segments, the change in healthy spinal segments can pinpoint the displaced unhealthy spinal segment and its degree of displacement. This allows for precise location of unhealthy spinal segments during orthopedic surgical navigation, preventing surgical deviations.

[0055] In addition, to enhance alertness and facilitate doctors' immediate understanding of the real-time displacement of the spine, the displacement distance and angle of each healthy spinal segment that has experienced displacement can be displayed through the display module, as well as the displacement distance and angle of unhealthy spinal segments that have experienced displacement can be displayed in the first point cloud image or the second point cloud image.

[0056] In one embodiment, this application provides a spinal displacement positioning system for orthopedic surgical navigation, including a processor that stores computer programs or instructions to perform the steps of the spinal displacement positioning method of the above embodiments.

[0057] It should be noted that the above embodiments can be freely combined as needed. The above description is only a preferred embodiment of the present invention. It should be pointed out that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A spinal displacement positioning method for orthopedic surgical navigation, used in a spinal displacement positioning system, the spinal displacement positioning system comprising a plurality of fixed reference frames, the fixed reference frames being used to conform to the surface of the human skin along the direction of the human spine and corresponding to healthy spinal segments, each fixed reference frame being equipped with an ultrasound detection module, characterized in that, Including the following steps: Acquire a first point cloud image and a second point cloud image corresponding to unhealthy spinal segments of the human body for orthopedic surgical navigation, and calculate the transformation matrix between the first point cloud image and the second point cloud image; Ultrasound images of each healthy human spinal segment corresponding to the fixed reference frame are acquired by the ultrasound detection module on each of the fixed reference frames. The ultrasound image is mapped to the first point cloud image or the second point cloud image using the transformation matrix to obtain the position coordinates of each healthy human spinal segment corresponding to the fixed reference frame; The method of mapping the ultrasound image to the first point cloud image or the second point cloud image through the transformation matrix further includes: acquiring the three-dimensional data of the fixed reference frame and the position data of the ultrasound detection module on the fixed reference frame, and registering the mapping of the ultrasound image through the three-dimensional data and the position data; The position coordinates of each healthy human spinal segment corresponding to the fixed reference frame are monitored in real time, and an alarm is triggered and the change value of the position coordinates is recorded when the position coordinates change. The displacement of unhealthy spinal segments in the human body is located by using the aforementioned change values.

2. The spinal displacement positioning method according to claim 1, characterized in that, The method of locating displaced unhealthy spinal segments in the human body through the change value specifically includes: The displacement of the healthy human spinal segment is determined by the change in the position coordinates, as well as the displacement distance and angle of each displacement healthy human spinal segment. Interpolation calculations are performed on the displacement distance and angle of each displaced healthy spinal segment to locate the displaced unhealthy spinal segment and its displacement distance and angle.

3. The spinal displacement positioning method according to claim 1, characterized in that, The number of fixed reference frames is two, and they are respectively attached to the skin surface of the healthy spinal segments at both ends of the unhealthy spinal segments.

4. The spinal displacement positioning method according to claim 1, characterized in that, The acquisition of a first point cloud image and a second point cloud image corresponding to unhealthy spinal segments in the human body for orthopedic surgical navigation, and the calculation of the transformation matrix between the first point cloud image and the second point cloud image, specifically includes: A first point cloud image of a target region is acquired through a first imaging component. The target region includes the fixed reference frame and a region corresponding to an unhealthy segment of the human spine. The second point cloud image of the target area is acquired by the second imaging component, and the first point cloud image and the second point cloud image are registered by the fixed reference frame to obtain the transformation matrix between the first point cloud image and the second point cloud image.

5. The spinal displacement positioning method according to claim 4, characterized in that, The first imaging component is a CT scanning component.

6. The spinal displacement positioning method according to claim 4, characterized in that, The second imaging component is a binocular positioning device, and each of the fixed reference frames is equipped with a reflective ball assembly.

7. The spinal displacement positioning method according to claim 1, characterized in that, One side of the fixed reference frame is provided with an adhesive surface for conforming to the surface of human skin. The adhesive surface is an arc surface that conforms to the human body shape and / or the adhesive surface is an elastic surface.

8. The spinal displacement positioning method according to claim 2, characterized in that, Also includes: The display module shows the displacement distance and angle of each healthy human spinal segment that has experienced displacement, and also shows the displacement distance and angle of the unhealthy human spinal segments that have experienced displacement in the first point cloud image or the second point cloud image.

9. A spinal displacement positioning system for orthopedic surgical navigation, characterized in that, Includes a processor, which stores a computer program or instructions to perform the steps of the spinal displacement localization method according to any one of claims 1-8.

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