CN105559884B - A kind of total hip arthroplasty midpelvis attitude acquisition method and system - Google Patents

Abstract

The present invention is a method and system for acquiring pelvic posture in total hip replacement surgery. Before the operation, the pelvis static measurement device is used to determine the initial static pelvic front plane by measuring the initial static pelvic front plane; during the operation, the initial posture is used as a reference , align the pelvic dynamic measurement device with the pelvis to realize the real-time measurement of the pelvic posture during the operation; wherein, the pelvic static measurement device and the pelvic dynamic measurement device have the same measurement module, and the measurement module is provided with a data acquisition module, and the data acquisition module includes motion sensor. According to the function, the system can be divided into three modules: data acquisition, data processing and data transmission; according to the components, it can be divided into pelvic static measurement device and pelvic dynamic measurement device. Each part of the device is equipped with sensors to transmit the sensor data to the computer terminal in real time. The posture of the pelvis is calculated and displayed on the computer, and the present invention can obtain the posture of the pelvis in real time, and use the obtained posture of the pelvis as a reference for hip joint replacement surgery.

Description

A method and system for acquiring pelvic posture in total hip replacement surgery

technical field

The invention belongs to the technical field of medical electronics, and in particular relates to a method and system for acquiring pelvis posture in total hip replacement surgery.

Background technique

Since the 1960s, artificial joint replacement has gradually developed in my country and has become a blessing for countless patients with joint diseases. Taking hip replacement as an example, the first indication is osteoarthritis, followed by aseptic necrosis of bone (such as femoral head necrosis, etc.), some hip fractures (such as femoral neck fracture), rheumatoid joint Inflammation, traumatic arthritis, benign and malignant bone tumors, ankylosing spondylitis, etc., are widely used and relieve the pain of patients. As the population ages, the number of patients with osteoarthritis is on the rise, and more artificial joint replacements are performed each year.

An important aspect of hip replacement is ensuring proper alignment of the acetabular component relative to the pelvis. Studies have shown that acetabular components not properly aligned with the pelvis can lead to premature wear, tendency to dislocate, and patient discomfort. However, the biggest problem facing surgeons in hip replacement surgery today is how to achieve proper acetabular implant alignment.

The two most important angles for acetabular implant placement are abduction and anteversion. Generally agreed among orthopedic surgeons is the ideal anatomical position for positioning the acetabular prosthesis within the native bone of the host acetabulum (45° in abduction and 20° anteversion for most patients). ). However, the measurement of these specific angles and the placement of the prosthesis are only based on the doctor's experience, it is difficult to achieve accurate placement, and these ideal angles are relative to the patient's pelvis, and the patient is operated aseptically during the hip replacement surgery. single cover. Any changes in the position and posture of the patient's pelvis cannot be observed in real time during the operation, and the placement of the acetabular prosthesis based on the surgeon's experience alone will cause relatively large errors.

Contents of the invention

In order to overcome the above-mentioned shortcomings of the prior art, the object of the present invention is to provide a method and system for obtaining the posture of the pelvis in total hip replacement surgery, which can accurately simulate the real-time posture of the pelvis during hip replacement surgery, so that doctors can The acetabular prosthesis can be placed relatively accurately during the operation, which greatly improves the success rate and surgical efficacy of hip replacement.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A method for acquiring the posture of the pelvis in total hip replacement surgery, wherein:

Before operation, use the pelvic static measurement device to determine the initial posture of the pelvis by measuring the initial static anterior plane of the pelvis;

During the operation, based on the initial posture, the pelvic dynamic measurement device is aligned with the pelvis to realize real-time measurement of the posture of the pelvis during the operation;

Wherein, the pelvic static measurement device and the pelvic dynamic measurement device have the same measurement module, and the measurement module is provided with a data acquisition module, and the data acquisition module includes a motion sensor.

The motion sensor acquires the posture data of the pelvis, sends the obtained posture data wirelessly, and uses the wireless receiving device to receive the data signal and process it on the computer, finally displaying the real-time posture data of the pelvis.

A pelvic posture acquisition system in total hip replacement surgery, comprising:

A pelvic static measurement device for measuring the initial posture of the pelvis;

A pelvic dynamic measurement device for measuring the real-time posture of the pelvis according to the initial posture of the pelvis;

Wherein, both the pelvis static measurement device and the pelvic dynamic measurement device are provided with a pelvis measurement module, the pelvis measurement module includes a data acquisition module, and the data acquisition module includes a motion sensor.

Described pelvic static measurement device comprises fixed base one 2 and fixed base two 6, and fixed base one 2 and fixed base two 6 are all provided with rotating rod 1, and the stretchable rod 4 that marks scale 3 is connected on Between the two rotating rods 1, the top of one of the rotating rods 1 is installed with a pelvic measurement module-5.

The pelvic dynamic measurement device includes a second pelvic measurement module 11 and a needle 12 for fixing the second pelvis measurement module 11 on the pelvic plane.

Described pelvis measurement module one 5 and pelvis measurement module two 11 structures are consistent, all comprise protective shell 21, and motion sensor 22 is arranged in protective shell 21, and described motion sensor 22 comprises three-axis accelerometer, three-axis gyroscope and three-axis magnetic force count.

The pelvic posture acquiring system in the total hip replacement operation may also include:

The data processing module is used to store the data collected by the motion sensor in a buffer;

A data transmission module, configured to send a frame of data in the buffer to the in vitro processor;

The extracorporeal processor receives the data sent by the data transmission module, extracts the motion data, and obtains the real-time posture of the pelvis in the hip replacement operation.

The data processing module is realized by an MCU; the data transmission module sends the data out through wifi, and the external processor is a computer.

The extracorporeal processors include:

A data extraction module for disassembling the data from the data transmission module into acceleration data, geomagnetic data and angular velocity data;

A static and dynamic attitude measurement module for the pelvis according to the obtained data;

The display module is used to display the posture data calculated by the posture measurement module to facilitate surgeons to perform hip joint replacement surgery better.

The use of the present invention will greatly reduce the difficulty for doctors to perform total hip replacement surgery, and improve the success rate and curative effect of the operation.

Description of drawings

Fig. 1 is a schematic diagram of the product and mechanical structure of the system of the present invention.

Figure 2 is a diagram of the structure of the pelvis.

Fig. 3 is a hardware functional block diagram of the system of the present invention.

Fig. 4 is a software functional block diagram of the system of the present invention.

Detailed ways

The implementation of the present invention will be described in detail below in conjunction with the drawings and examples.

The invention provides a method and system for acquiring pelvic posture in total hip replacement surgery, which can measure the pelvic posture in real time when the total hip replacement operation is in progress, thereby bringing convenience to surgeons for surgical operations.

A kind of example product sketch map of the present invention is as shown in Figure 1, and wherein the device shown in frame II is the pelvis static measurement device, is used for measuring the static pelvis front plane that is the initial attitude of the pelvis, comprises fixed base one 2 and fixed base two 6. Both the fixed base 1 2 and the fixed base 2 6 are provided with a rotating rod 1, and the stretchable rod 4 marked with a scale 3 is connected between the two rotating rods 1, wherein the rotating rod on the fixed base 2 6 A pelvic measurement module-5 is installed on the top of the 1.

The device shown in frame I is a pelvic dynamic measurement device, including a pelvis measurement module 2 11 and a needle 12 for fixing the pelvis measurement module 2 11 on the pelvic plane.

Frame III is an enlarged view of the pelvis measurement module 1 5 and the pelvis measurement module 2 11. The pelvis measurement module 1 5 and the pelvis measurement module 2 11 have the same structure, and both include a protective shell 21, and a motion sensor 22 and other necessary components are arranged in the protective shell 21. Elements, the motion sensor 22 includes a three-axis accelerometer, a three-axis gyroscope, and a three-axis magnetometer.

In order to ensure the clarity of the following description, now briefly introduce the structure of the pelvis, see Figure 2. Feature point A in the figure is the pubic symphysis, and feature points B and C are the right anterior superior iliac spine and the left anterior superior iliac spine, respectively. To measure the posture of the pelvis is to measure the posture of the anterior plane of the pelvis composed of these three points.

According to the above structure, the following is the operation process for the doctor to use this embodiment in total marrow joint replacement surgery:

Step 1. The doctor removes the patient's acetabular necrosis and disease;

Step 2. Put the battery into the pelvic measurement module-5 (power on), place the patient in a comfortable position, and ensure that the front plane of the pelvis is in a measurable position;

Step 3. The doctor places the fixed base 1 of the pelvic static measurement device on the pubic symphysis, and adjusts the length of the stretch rod to make the length of the device meet the patient's pelvic measurement needs (such as: make the fixed base 1 2 and the fixed base 2 The distance between 6 is equal to the distance between the right anterior superior iliac spine and the pubic symphysis), and the fixed base 26 at the other end of the measuring device is placed on the right anterior superior iliac spine;

Step 4. The doctor turns on the computer and the corresponding program. At this time, the posture of the pelvis measurement module-5 at the right anterior superior iliac spine can be measured, and the posture of the pelvis measurement module-5 at this time can be recorded by pressing keys. The rotating rod 1 is rotated around the axis to the left anterior superior iliac spine, and the attitude of the measurement module 1 5 at this location is also recorded. The specific principles are as follows:

(1) Record the attitudes of the dynamic measurement device at C-A and B-A in Fig. 2 and measure module one 5 respectively, expressed as euler1 and euler2 in terms of Euler angles.

(2) Through the angle measured in (1), calculate the vector value of the x-axis of the corresponding measurement module-5 in the world coordinate system and Will and Perform a cross product to get the normal vector of the coronal plane (parallel to the front plane of the pelvis)

(3) Through the angle measured in (1), calculate the vector value of the y-axis of the corresponding measurement module-5 in the world coordinate system and Will and Carry out the cross product to get the normal vector of the sagittal plane (From left to right, ie C→B in Figure 2).

(4) get and That is, the posture of the pelvis is obtained.

Step 5. The doctor removes the pelvic static measurement device, aligns the pelvic dynamic measurement device with the initial posture of the pelvis measured in step 4, and fixes the needle 12 of the pelvic dynamic measurement device on a certain feature point, such as the right anterior superior iliac spine B.

Step 6. The doctor can place the patient in a posture that is convenient for the operation. Since the pelvic dynamic measurement device and the pelvis have been fixed through step 5, the posture of the pelvis can be measured in real time.

Step 7. The doctor places the acetabulum according to the real-time posture of the pelvis measured in step 6. The same measuring device should be placed on the acetabulum so that the angle of the acetabulum relative to the pelvis can be calculated by referring to the posture of the pelvis.

The function implementation of this embodiment mainly includes two parts: hardware and software. The hardware part is mainly the above-mentioned pelvis measurement module, and its realization principle is shown in Fig. 3 . According to the function, it is divided into data acquisition module (sensor module), data processing and data transmission module, and the circuits for realizing these functions are located in the pelvis measurement module.

The following describes the workflow of the hardware part:

Step 1. The battery supplies power to each module;

Step 2. The data processing module is implemented by the MCU, and the motion sensor is configured after power-on;

Step 3. Each sensor starts to collect data, and the motion sensor samples the three-axis acceleration, angular velocity, and geomagnetic field strength at a frequency of 50HZ;

Step 4. The data processing module stores the data collected by the motion sensor in the buffer;

Step 5. After completing the data collection, send the data in wireless (wifi) mode;

Step 6. After the sending is completed, jump to step 3 and repeat the cycle.

The software part of this embodiment is mainly realized in the extracorporeal processor, such as the computer shown in FIG. 4 . According to the function, it can be divided into three parts: data extraction module, attitude calculation module and attitude display module, as shown in Figure 4. The software is installed on a computer outside the body, and the workflow of the software is as follows:

Step 1. In the data acquisition stage, the computer receives the mixed data from the hardware and splits it into acceleration data, geomagnetic data and angular velocity data;

Step 2. Static attitude measurement, determine the rotation angle around the vertical axis according to the three-axis geomagnetic data, determine the rotation angle around the two horizontal axes through the three-axis acceleration data, and then obtain the static attitude data;

Step 3. Dynamic attitude measurement. Dynamic attitude detection can be performed according to the three-axis angular velocity data. The basic principle is to integrate the three-axis angular velocity data to obtain the rotation angle around each axis;

Step 4. Carry out data fusion between the data obtained by static attitude calculation and the data obtained by angular velocity integration, that is, the Kalman filter in Figure 4, to obtain the final dynamic attitude data of the pelvis;

Step 5. Display the finally obtained pose data in a way that is easy to understand intuitively.

After the above software work is done, the doctor can ensure that the artificial acetabular fits at the proper angle, thereby avoiding premature wear, tendency to dislocation, and patient discomfort.

Claims (5)

1. a kind of total hip arthroplasty midpelvis posture obtains system, which is characterized in that including：

Pelvis static measuring devices for measuring pelvis initial attitude, the pelvis static measuring devices include fixed pedestal one (2) and fixed pedestal two (6) it, is both provided with swingle (1) on fixed pedestal one (2) and fixed pedestal two (6), indicates scale (3) stretchable bar (4) is connected between two swingles (1), and pelvimetry module is installed at the top of one of swingle (1) One (5)；

Pelvis dynamic measurement device for measuring pelvis real-time attitude according to pelvis initial attitude, pelvis dynamic measurement device packet Include pelvimetry module two (11) and the needle (12) for pelvimetry module two (11) to be fixed on to pelvic plane；

The pelvimetry module one (5) is consistent with pelvimetry module two (11) structure, includes protective shell (21), protective shell (21) setting motion sensor (22) in, the motion sensor (22) includes three axis accelerometer, three-axis gyroscope and three axis Magnetometer.

2. total hip arthroplasty midpelvis posture obtains system according to claim 1, which is characterized in that further include：

Data processing module, there are buffering areas for the data for acquiring motion sensor；

Data transmission module, for the frame data in the buffering area to be sent to extracorporeal treatment device；

Extracorporeal treatment device receives the data that the data transmission module is sent, and extracts exercise data, obtains hip replacement surgery The real-time attitude of midpelvis.

3. total hip arthroplasty midpelvis posture obtains system according to claim 2, which is characterized in that the data Processing module is realized by a MCU；The data transmission module is sent outside data using wifi modes, and the extracorporeal treatment device is Computer.

4. obtaining system according to total hip arthroplasty midpelvis posture described in Claims 2 or 3, which is characterized in that described Extracorporeal treatment device includes：

For the data that the data dismantling from data transmission module is acceleration information, geomagnetic data and angular velocity data to be carried Modulus block；

Calculate module with dynamic posture for carrying out pelvis static state according to the data of acquisition；

The attitude data calculated for showing posture measuring and calculating module, facilitates surgeon preferably to carry out hip replacement hand The display module of art.

5. total hip arthroplasty midpelvis posture obtains system according to claim 4, which is characterized in that described external Processor determines the corner around vertical axis, passes through 3-axis acceleration number according to three axis geomagnetic data in pelvis static measuring devices According to determining around two horizontal Shaft angles, and then obtain static attitude data；The extracorporeal treatment device is according to pelvis dynamic measurement device In three axis angular rate data into Mobile state attitude detection, basic principle is to integrate three axis angular rate data, obtain around The rotation angle of each axis, by the data resolved by static attitude and the data that are integrated by angular speed into line number According to fusion, i.e. Kalman filtering, to obtain final pelvis dynamic attitude data.