A precise rehabilitation system for abnormal posture with personalized feedback electrical stimulation

Abstract

The present invention discloses a personalized feedback electrical stimulation system for accurate rehabilitation of abnormal postures. The system includes a main control module, a host computer processing module, an inertial sensor unit and surface electrodes. The system can collect surface electromyographic signals (sEMG) and back posture data of specific points of the user in real time and output electrical stimulation of a specific intensity to assist the user to accurately and effectively correct bad postures. The user's current posture is analyzed by the back multi-point inertial sensor unit IMU, and the muscle contraction state is analyzed by the average rectified electromyographic value (AEMG) of the electromyographic signals of the chest and back muscles. At the same time, the system can output feedback electrical stimulation through the surface electrodes attached to the user's back. Based on the personalized feedback electrical stimulation algorithm, the analysis of the user's personalized data, current posture, and muscle contraction state is integrated to output personalized electrical stimulation parameters with reasonable intensity to accurately assist the user to contract the back muscles, thereby achieving the purpose of training the back muscle contraction and correcting bad postures.

Description

Technical Field

[0001] The present invention belongs to the field of intelligent rehabilitation equipment, and in particular relates to an abnormal posture precision rehabilitation system with personalized feedback electrical stimulation. Background Art

[0002] Postural kyphosis in adolescents is a common abnormal posture in modern society and has been a research hotspot in the field of physical health of children and adolescents in recent years. Its pathogenesis involves multiple factors, including age, gender, race, bones, muscles, ligaments and posture factors. A healthy spine is the basis for maintaining normal posture and motor ability of the human body. Adolescents are in a stage of rapid physical development, and their nervous system and musculoskeletal system are not yet fully mature. Excessive kyphosis of the spine not only affects the appearance of the body, but may also cause spinal degeneration, decreased physical function, impaired respiratory function, and restricted development of internal organs, which seriously affect the physical and mental health of adolescents.

[0003] The main reason for postural kyphosis is that long-term abnormal posture leads to unbalanced development of the flexors and extensors of the spine, and the back muscles will atrophy to a certain extent due to long-term relaxation. The impact of bad body postures such as postural kyphosis on bone health is slow and continuous. Abnormal posture will cause the human skeletal muscle system to transition from functional changes to organic changes. If you wait until adulthood, disease or pain has occurred before treatment, it will be too late. As a key factor affecting adolescent body posture, adolescent postural kyphosis has attracted much attention. Domestic and foreign studies have shown that active intervention combined with electrical stimulation is an effective way to improve this phenomenon. The Cobb angle is the current standard back measurement method. It is named after John Robert Cobb, an American orthopedic surgeon. It is obtained by measuring the angle between the two most inclined vertebrae in the spinal X-ray. This method was originally used to measure scoliosis, and then it was modified and applied to the measurement of lateral thoracic spine X-rays. The thoracic vertebrae 1 to 3 are not easy to see clearly because of overlapping images of the ribs and shoulders on X-rays. Therefore, the thoracic vertebrae 4 (T4) and thoracic vertebrae 12 (T12) are often used as reference points for measurement. This angle is measured by the intersection of the upper endplate of the T4 vertebra and the extension of the lower endplate of the T12 vertebra. Figure 8 When the angle measured by angle A is greater than 40 degrees, it is a hunchback.

[0004] Chinese patent CN108514689A discloses an electric stimulation posture correction method and posture correction device, wherein the electric stimulation posture correction device includes: a collection module, a posture data processing module and an electric stimulation module, wherein the collection module is used to collect posture data of the part to be corrected; the posture data processing module is used to judge whether the posture change meets the trigger condition based on the posture data collected by the collection module, and if so, output an electric stimulation instruction to the electric stimulation module; the electric stimulation module is used to output electric stimulation based on the received electric stimulation instruction to prompt the part to be corrected to correct the posture. The embodiment of the present application improves the posture correction effect of the posture correction device.

[0005] However, due to the differences in individual muscle characteristics, the same electrical stimulation parameters have different effects on different individual muscles. The Chinese patent CN108514689A determines the electrical stimulation parameters based on posture changes, which makes it difficult for different patients to obtain the same effective posture correction effect. The same parameters may not achieve the electrical stimulation effect for some patients, but may cause obvious tingling for other patients. How to effectively and accurately implement personalized electrical stimulation is the main problem that needs to be solved at present. Summary of the invention

[0006] The purpose of the present invention is to address the deficiencies in the prior art and to provide a precise rehabilitation system for abnormal posture with personalized feedback electrical stimulation. Through this system, the user's back condition and degree of postural kyphosis can be effectively determined, and personalized electrical stimulation can be implemented to assist posture correction according to different individual users and muscle conditions, so as to achieve effective posture correction by effective muscle stimulation.

[0007] The object of the present invention is achieved through the following technical solution: a personalized feedback electrical stimulation abnormal posture accurate rehabilitation system, the system comprising:

[0008] Inertial sensor unit (IMU) to measure the user's Angle, to judge the degree of hunchback;

[0009] Surface electrodes are attached to the belly of the pectoralis major and the middle belly of the trapezius muscle to collect electromyographic signals and apply electrical stimulation;

[0010] The main control module is used to measure the The angle is used to judge the degree of hunchback of the user. When the user is in a state of muscle relaxation, the Cobb angle of the body posture is detected. , the user's posture is normal, the system will give a normal posture prompt, and no posture correction is needed; if , the user has severe hunchback, and the system will give a severe hunchback prompt and recommend that the user undergo professional medical intervention; if , it is a mild kyphosis, if , it is moderate kyphosis, and the system can determine the electrical stimulation correction threshold based on the electromyographic signals collected by the surface electrodes and the degree of kyphosis;

[0011] Host computer processing module, calculates user Quality factor of the state and Quality factor of the state and the quality factor of the user in a relaxed state ; The quality factor is the difference between the average rectified EMG values ​​of the EMG signals of the chest muscles and the back muscles; and calculate , and then the calculation result is corrected through the electrical stimulation correction threshold to determine the personalized electrical stimulation intensity combined with the hunchback state, and then the electrical stimulation instruction is issued.

[0012] Furthermore, one of the inertial sensor units (IMU) is attached to the seventh cervical vertebra C7 or the first thoracic vertebra T1 on the user's back, and the other is attached to the twelfth thoracic vertebra T12. The inclination angles of the two cervical planes can be obtained respectively through the two inertial sensor units, and then the angle between the two cervical planes, namely the Cobb angle, can be calculated.

[0013] Furthermore, the surface electrodes are attached to the user's pectoralis major muscle bellies SE11, SE12 and the middle trapezius muscle bellies SE21, SE22, wherein SE11 and SE12 are used for surface electromyography acquisition, and SE21 and SE22 are used for both surface electrical stimulation and electrical stimulation output.

[0014] Further, the process of determining the correction threshold of electrical stimulation is as follows: applying electrical stimulation to the middle part of the back trapezius muscle, namely the surface electrodes SE21 and SE22, with the intensity being determined by Start with The step value increases slowly. If the kyphosis is mild, the threshold at which the user can feel the electrical stimulation is recorded. As the correction threshold of electrical stimulation; if it is moderate kyphosis, the movement threshold of the back muscles relying on electrical stimulation in the user's active relaxation state is recorded as As the threshold for electrical stimulation correction.

[0015] Further, It is a weak pulse current used to activate muscles and remind them to actively contract; It uses pulse cluster current stimulation to promote muscle contraction and provide stronger traction.

[0016] Furthermore, the quality factor The specific calculation formula is:

[0017]

[0018] in is the average rectified electromyographic value of the chest muscles , is the average rectified electromyographic value of the back muscles , through the quality factor Characterizes the difference in contraction between the chest muscles and the back muscles, which varies from user to user.

[0019] Furthermore, the average rectified electromyographic value AEMG is proportional to the muscle nerve recruitment capacity, reflecting the active contraction strength of the muscle; its calculation formula is:

[0020]

[0021] EMG is the effective electromyographic value collected, and N is the number of data points per unit time.

[0022] Furthermore, the formula for determining the personalized electrical stimulation intensity combined with the hunchback state is:

[0023]

[0024] in, Indicates the intensity of personalized feedback electrical stimulation. The Cobb in this formula is the real-time angle. If the user is in a normal posture, electrical stimulation will not be triggered or will stop being triggered. If the user has a severe hunchback, it is recommended that the user undergo professional medical intervention.

[0025] Furthermore, the host computer processing module determines the user's muscle fatigue condition, and the calculation formula is as follows:

[0026]

[0027] Among them, MPF represents the mean power frequency, and its value decreases as the degree of muscle fatigue deepens, indicating the muscle fatigue situation. is the power spectral density, is the EMG signal frequency, and is the cutoff frequency of the bandpass filter; when the average power frequency MPF is less than or equal to the preset fatigue threshold MPF(th), the muscle fatigue warning is triggered, the output of electrical stimulation is stopped, and the user is advised to adjust his posture to relax his muscles.

[0028] Furthermore, the host computer processing module displays the electromyography data waveform and the back posture image in real time.

[0029] Beneficial effects of the invention: Based on the causes of postural kyphosis caused by abnormal posture and the current status of related research, the invention fully considers the differences in muscles of different individuals and provides a personalized feedback electrical stimulation abnormal posture precision rehabilitation system, which can customize different parameters for the feedback electrical stimulation algorithm for different individual muscles. The invention enables different users to obtain appropriate electrical stimulation treatment effects during use, while avoiding problems such as tingling and muscle fatigue caused by excessive electrical stimulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 A system block diagram of a personalized feedback electrical stimulation abnormal posture precision rehabilitation system provided by an embodiment of the present invention;

[0032] Figure 2 The arrangement sites of the surface electrodes and the inertial sensor unit in the abnormal posture precision rehabilitation system with personalized feedback electrical stimulation provided by an embodiment of the present invention;

[0033] Figure 3 A schematic diagram of a process flow of a method for accurate rehabilitation of abnormal postures with personalized feedback electrical stimulation provided by an embodiment of the present invention;

[0034] Figure 4 The electromyographic time domain diagram display of the host computer processing module in the abnormal posture precise rehabilitation system with personalized feedback electrical stimulation provided by the embodiment of the present invention can indicate the change of muscle contraction intensity;

[0035] Figure 5 The myoelectric power spectrum display of the host computer processing module in the abnormal posture precise rehabilitation system with personalized feedback electrical stimulation provided by the embodiment of the present invention can indicate the degree of muscle fatigue;

[0036] Figure 6 A processing function setting diagram of a host computer processing module in a personalized feedback electrical stimulation abnormal posture precision rehabilitation system provided by an embodiment of the present invention;

[0037] Figure 7 This is a diagram of the analysis function results of the host computer processing module in the abnormal posture precision rehabilitation system with personalized feedback electrical stimulation provided in an embodiment of the present invention.

[0038] Figure 8 Schematic diagram of the Cobb angle in the present invention. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical scheme and advantages of the embodiment of the present invention clearer, the technical scheme in the embodiment of the present invention will be clearly and completely described in combination with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. The components of the embodiment of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiment of the present invention provided in the drawings is not intended to limit the scope of the claimed patent of the present invention, but merely represents the selected embodiment of the present invention. Based on the embodiment of the present invention, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of this application.

[0040] The present invention provides a personalized feedback electrical stimulation system for accurate rehabilitation of abnormal postures, such as Figure 1 As shown: It includes a main control module, surface electrodes, an inertial sensor unit, and a host computer processing module.

[0041] The main control module is a wearable internal power supply device, which has a microcontroller, an internal power supply circuit, a function selection circuit, a signal acquisition circuit, an electrical stimulation output circuit, a Bluetooth module and other modules. The microcontroller is the central processing unit of the main control module, which mainly realizes the reception and processing of host computer instructions; the internal power supply circuit has a safety isolation design, which complies with relevant medical device safety standards such as YY 9706.240-2021; the function selection module is mainly used to realize the electrode multiplexing technology of electromyography acquisition and electrical stimulation, and to shut down the electrical stimulation output when abnormal operation is detected to protect user safety and equipment safety; the signal acquisition circuit is mainly used for the acquisition of electromyography signals; the electrical stimulation output circuit is mainly used for the generation and output of electrical stimulation pulses; the Bluetooth module is mainly used for wireless Bluetooth transmission of data and instructions. The main control module is connected to the inertial sensor unit and the surface electrode, and is used to receive electromyography signals and posture data, and send them to the host computer processing module after preprocessing. It has electromyography signal acquisition function, posture data acquisition function, electrical stimulation output function and Bluetooth wireless transmission function;

[0042] The surface electrodes are connected to the main control module, such as Figure 2 As shown, they are attached to the user's pectoralis major muscle belly (SE11, SE12) and the middle trapezius muscle belly (SE21, SE22), wherein SE11 and SE12 are used for surface electromyography acquisition, and SE21 and SE22 are used for both surface electrical stimulation and electrical stimulation output;

[0043] The inertial sensor unit is connected to the main control module, such as Figure 2As shown, one piece is attached to the 7th cervical vertebra (C7) or the 1st thoracic vertebra (T1) on the back of the user, and the other piece is attached to the 12th thoracic vertebra (T12). The inclination angles of the two cervical planes can be obtained through the two inertial sensor units, and then the angle between the two cervical planes, namely the Cobb angle, can be calculated, which can be used to calibrate the current degree of back curvature of the user.

[0044] The host computer processing module is a mobile terminal software that can be wirelessly connected to the main control module and is used to receive the electromyographic data and posture data transmitted by the main control module in real time. It has data processing function, status display function, electromyographic analysis function and electrical stimulation intensity feedback calculation function; it is also used to issue power generation stimulation instructions to the main control module based on the data analysis results.

[0045] The electromyographic signal acquisition function of the main control module can receive the electromyographic signals collected by the surface electrodes and convert the signals into data. After the data is encrypted and packaged by a specific algorithm, it is transmitted to the host computer processing module via the Bluetooth transmission function.

[0046] The posture data acquisition function of the main control module can receive the inertial sensor unit data, and after encrypting and packaging the data, transmit it to the host computer processing module through the Bluetooth transmission function.

[0047] The electrical stimulation output function of the main control module can output symmetrical and balanced biphasic rectangular waves of different modes, amplitudes, frequencies and pulse widths according to instructions, and has safety protection measures such as amplitude limitation, time limitation and short circuit protection.

[0048] The Bluetooth transmission function of the main control module can connect to the host computer processing module through Bluetooth, transmit data, receive and execute relevant instructions of the host computer;

[0049] The display function of the host computer processing module includes: after decoding the electromyographic data and the posture data, the waveform and the back posture image can be displayed in real time.

[0050] The processing functions of the host computer processing module include: Cobb angle calculation of posture data, baseline correction of electromyographic data, power frequency and its multiple frequency notch adjustment, bandpass filter adjustment, etc.

[0051] The parameters output by the electromyography analysis function of the host computer processing module mainly include: maximum value (MAX / MIN) calculation, root mean square value (RMS) calculation, median frequency (MDF) calculation, average rectified electromyography (Averaged Electromyography, AEMG) and mean power frequency (Mean Power Frequency, MPF) etc.

[0052] The average rectified electromyographic value (AEMG) is proportional to the muscle nerve recruitment ability and can reflect the active contraction strength of the muscle. Its calculation formula is: , where N is the number of data points per unit time. The system host computer software processes data at an interval of 100ms. Taking 1kHz sampling rate as an example, .

[0053] The mean power frequency (MPF) decreases as the degree of muscle fatigue increases, which can characterize the muscle fatigue. Its calculation formula is: ,in is the power spectral density, is the EMG signal frequency, and is the cutoff frequency of the bandpass filter. The default value of this system is .

[0054] The flowchart of determining the intensity of personalized feedback electrical stimulation provided by the present invention is as follows: Figure 3 First, define is the average rectified electromyographic value of the chest muscles ( ), is the average rectified electromyographic value of the back muscles ( ), through the quality factor of personalized products , which can characterize the difference in contraction between chest muscles and back muscles, and this difference value varies from person to person. Figure 2 After attaching the inertial sensor unit and the surface electrode, follow the steps below to record personalized data : Log in user The quality factor at ; Record user The quality factor at Apply electrical stimulation to the middle part of the back trapezius muscle (i.e., surface electrodes SE21 and SE22), and slowly increase the intensity from 0 to 0.1 mA. Record the threshold at which the user can feel the electrical stimulation. . For weak pulse current, when , which is a mild kyphosis, mainly activates the muscles and reminds them to actively contract; electrical stimulation is applied to the middle part of the back trapezius muscle (i.e., surface electrodes SE21 and SE22), with an intensity of Start to increase slowly with a step value of 0.1mA, and record the motor threshold of the back muscles under the user's active relaxation state by electrical stimulation. . Pulse current stimulation is used. , which is a moderate kyphosis, mainly plays the role of promoting muscle contraction and providing stronger traction.

[0055] After the personalized data is determined, the system is bound to the user and can monitor the user's back posture in real time through the IMU. (moderate hunchback), calculate the personalized quality factor at this time , and intelligently output electrical stimulation to assist posture correction. The intensity of electrical stimulation is determined by the following formula:

[0056]

[0057] It should be pointed out that, firstly, if the user's back movement is limited and cannot be flexed and extended at different angles, this is physiological kyphosis and is not applicable to the present invention. It is recommended that the user undergo professional medical intervention. Secondly, if the user is in a state of prolonged or physical relaxation, the back bending angle is , which is a severe kyphosis, and users are also advised to undergo professional medical intervention.

[0058] During the monitoring period, the user's muscle electromyography can also be observed in real time, such as Figure 4 and Figure 5 In different environments, the filter parameters can be manually adjusted to obtain better EMG, such as Figure 6 The host computer software can also calculate the electromyography related parameters to obtain the muscle condition and provide the user with an analysis report, which can contain other indicators for the user to view, such as Figure 7 To prevent muscle fatigue caused by excessive electrical stimulation, the present invention also provides a muscle fatigue warning function, which can set the fatigue threshold MPF(th). The default value of this system is MPF(th)=70Hz. If MPF≤MPF(th) is detected, the system triggers a muscle fatigue warning, stops outputting electrical stimulation, and recommends that the user adjust his posture to relax his muscles. The system provided by the present invention can define different personalized electrical stimulation parameters according to the different muscle states of each user. When the user is in a normal posture, the electrical stimulation is not triggered or stops being triggered; when When , it is a severe kyphosis, and the user is advised to undergo professional medical intervention, such as corrective surgery, which does not belong to the application scope of the present invention; when The present invention triggers electrical stimulation of corresponding intensity to assist users in correcting bad postures. Compared with traditional electrical stimulation posture correction equipment, the physical therapy parameters are more accurate, and the physical therapy parameters can be changed in real time according to the patient's muscle state to accurately assess the degree of hunchback of the user.

[0059] Finally, it should be noted that: The above-described embodiments provide a detailed description of the technical solutions and beneficial effects of the present invention. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements and equivalent substitutions made within the scope of the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A personalized feedback electrical stimulation system for accurate rehabilitation of abnormal posture, characterized in that: The system includes: An inertial sensing unit, which is used to measure the Cobb angle of the user and judge the degree of hunchback; Surface electrodes, which are attached to the belly of the pectoralis major muscle and the middle belly of the trapezius muscle, collect electromyographic signals and apply electrical stimulation; A main control module, which is used to judge the degree of hunchback of the user according to the Cobb angle measured by the inertial sensing unit. If 40° < Cobb < 50°, it is mild hunchback. If 50° < Cobb < 70°, it is moderate hunchback; determine the electrical stimulation correction threshold according to the electromyographic signals collected by the surface electrodes combined with the degree of hunchback; The host computer processing module calculates the quality factor Q0 of the user in the Cobb<40° state and the quality factor Q1 in the Cobb>70° state, as well as the quality factor Q in the user's relaxed state; the quality factor is the difference between the average rectified electromyographic values ​​of the electromyographic signals of the chest muscles and the back muscles; and calculates Then, the calculated result is corrected by the electric stimulation correction threshold, and the personalized electric stimulation intensity combined with the hunchback state is determined, and the electric stimulation instruction is issued; the process of determining the electric stimulation correction threshold is as follows: apply electric stimulation to the middle part of the back trapezius muscle, and the intensity is slowly increased from 0 to 0.1mA step value. If it is a mild hunchback, record the threshold I at which the user can feel the electric stimulation weak As the correction threshold of electrical stimulation; if it is moderate kyphosis, record the movement threshold of the back muscles relying on electrical stimulation in the user's active relaxation state as I move As the correction threshold of electrical stimulation; the formula for determining the personalized electrical stimulation intensity combined with the hunchback state is: Among them, I r Indicates the intensity of personalized feedback electrical stimulation. When Cobb<40°, the user is in a normal posture, and electrical stimulation will not be triggered or will stop being triggered. If the user is in a normal posture for a long time or the body is relaxed, and when Cobb>70°, it is severe kyphosis, and the user is advised to undergo professional medical intervention.

2. According to claim 1, a personalized feedback electrical stimulation abnormal posture precise rehabilitation system is characterized by: One piece of the inertial sensing unit is attached to the 7th cervical vertebra C7 or the 1st thoracic vertebra T1 of the user's back, and the other piece is attached to the 12th thoracic vertebra T12. The Cobb angle is calculated through the included angle of the two cervical vertebra planes.

3. The abnormal posture precise rehabilitation system with personalized feedback electrical stimulation according to claim 1, characterized in that: The surface electrodes are attached to the belly of the pectoralis major muscle SE11, SE12 and the middle belly of the trapezius muscle SE21, SE22 of the user. Among them, SE11 and SE12 are used for surface electromyography acquisition, and SE21 and SE22 are used for both surface electrical stimulation and electrical stimulation output.

4. The abnormal posture precise rehabilitation system with personalized feedback electrical stimulation according to claim 1, characterized in that: I weak It is a weak pulse current used to activate muscles and remind them to actively contract; I move It uses pulse cluster current stimulation to promote muscle contraction and provide stronger traction.

5. The abnormal posture precise rehabilitation system with personalized feedback electrical stimulation according to claim 1, characterized in that: The specific calculation formula of the quality factor Q is: Q=AEMG chest -AEMG back Among them AEMG chest is the average rectified electromyographic value of the chest muscles AEMG, AEMG back is the average rectified electromyographic value AEMG of the back muscles. The quality factor Q is used to characterize the contraction difference between the chest muscles and the back muscles. The individual contraction difference varies from user to user.

6. The abnormal posture precise rehabilitation system with personalized feedback electrical stimulation according to claim 5, characterized in that: The average rectified electromyogram value AEMG is proportional to the muscle nerve recruitment ability and reflects the active contraction intensity of the muscle; its calculation formula is: Where EMG is the effective electromyogram value collected, and N is the number of data points per unit time.

7. The abnormal posture precise rehabilitation system with personalized feedback electrical stimulation according to claim 1, characterized in that: The upper computer processing module determines the muscle fatigue condition of the user, and the calculation formula is as follows: Among them, MPF represents the mean power frequency, and its value decreases as the degree of muscle fatigue deepens, characterizing the muscle fatigue condition. P(f) is the power spectral density, f is the electromyogram signal frequency, and f1 and f2 are the cut-off frequencies of the band-pass filter; when the mean power frequency MPF is less than or equal to the preset fatigue threshold MPF(th), a muscle fatigue warning is triggered, the electrical stimulation output is stopped, and the user is advised to adjust the posture to relax the muscles.

8. The abnormal posture precise rehabilitation system with personalized feedback electrical stimulation according to claim 1, characterized in that: The upper computer processing module displays the electromyogram data waveform and the back posture image in real time.

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