CN114848245B - Knee joint replacement gap balance measurement system, preparation method and measurement method - Google Patents

Abstract

The invention relates to a knee joint replacement gap balance measuring system, a preparation method and a measuring method, wherein the knee joint replacement gap balance measuring system comprises an ionization type capacitance pressure sensing array gasket module, a capacitance array signal acquisition processing module and a knee joint two-side pressure distribution display module, an electrode array unit of the ionization type capacitance pressure sensing array gasket module comprises a plurality of ionization type capacitance pressure sensing electrodes which are distributed at the inner side and the outer side of knee joint soft tissue in an array mode, an ion gel dielectric layer is arranged, and the capacitance array signal acquisition processing module is connected with the ionization type capacitance pressure sensing array gasket module and the knee joint two-side pressure distribution display module. The preparation method comprises the step of preparing the ionization type capacitance pressure sensing array gasket module. The measurement method comprises the steps of collecting capacitor array data of different angles, and sending the data to the pressure distribution display modules on two sides of the knee joint through signal amplification and digital-to-analog conversion. The invention can provide accurate evaluation for measuring the pressure distribution at two sides of the knee joint in the operation.

Description

Knee joint replacement gap balance measurement system, preparation method and measurement method

technical field

The invention relates to the technical field of biological and pressure balance measurement, in particular to a knee joint replacement gap balance measurement system, a preparation method and a measurement method.

Background technique

Knee osteoarthritis (OA) is a common chronic degenerative joint disease. Total knee arthroplasty (TKA) is the first choice for surgical treatment for patients with moderate-to-advanced severe osteoarthropathy. TKA surgery can effectively relieve pain and improve knee function in patients with osteoarthritis.

Soft tissue balance and lower extremity alignment are the two most important technical links in TKA surgery. Compared with the correction of lower extremity alignment, there is still a lack of accurate quantitative judgment methods for intraoperative soft tissue balance of the knee joint. Soft tissue imbalances can lead to knee pain, functional limitation, joint instability, prosthesis loosening, and poor patellar trajectory, all of which are important causes of knee revisions. Traditional soft tissue balancing techniques mainly include measured resection and gap balancing. The balance of soft tissue under these two techniques is more dependent on the surgeon’s own experience and subjective judgment, and lacks in different knee flexion angles. objective data feedback. Therefore, designing a measurement tool that can be used intraoperatively and can accurately assess soft tissue balance at various knee flexion angles has become an important topic in the field of TKA research.

At present, there are many units and companies at home and abroad conducting research on this pressure measurement system, the most representative ones are the VerasenseTM system from abroad and the Balansense system from Yimai Medical in China. In recent years, the VerasenseTM system has been widely used in European and American countries due to its advantages of simple operation and high quantification, which has effectively improved the accuracy of TKA surgery. However, the Verasense system only uses a single resistive pressure sensor in the center of the pressure-measuring pad for pressure measurement, which can only provide the pressure changes in the central weight-bearing area of the medial and lateral compartments of the knee joint, and cannot reflect the pressure distribution information on the entire medial and lateral compartment surfaces. . The Balansense system of Yimai Medical in China relies on three commercial Honeywell pressure sensor chips to estimate the pressure on the surface of the medial and lateral compartments. According to the detection, there is an obvious error in the stress generated at the edge of the osteotomy plane, and this part is often the most serious part of the gasket wear during TKA revision. Therefore, only by extracting the pressure distribution characteristics of the entire inner and outer surfaces of the soft tissue of the knee joint can the balance model of the medial and lateral ligaments be reasonably established, and the intraoperative soft tissue balance can be controlled accurately and efficiently.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a knee joint replacement gap balance measurement system, preparation method and measurement method, so as to solve the problem of inaccurate measurement of local pressure on the knee joint contact surface in the prior art.

To achieve the above object, the present invention adopts the following technical solutions:

A knee replacement gap balance measurement system, comprising:

The ionized capacitive pressure sensing array gasket module, the ionized capacitive pressure sensing array gasket module includes an electrode array unit, and the electrode array unit includes the position of the inner and outer sides of the knee joint soft tissue between the femur and the tibia according to the position A plurality of ionized capacitive pressure sensing electrodes distributed in an array, and an ion gel dielectric layer is contacted on the plurality of ionized capacitive pressure sensing electrodes;

Capacitor array signal acquisition and processing module, said capacitor array signal acquisition and processing module includes an AC operational amplifier measurement circuit, the AC operational amplifier measurement circuit is connected with the electrode array unit circuit, and is used to acquire, measure and analyze a plurality of ionized capacitors The capacitance signal of the pressure sensing electrode;

A pressure distribution display module on both sides of the knee joint, the pressure distribution display module on both sides of the knee joint is connected in communication with the capacitance array signal acquisition and processing module for acquiring and displaying the analyzed and processed capacitance signals.

Further, the electrode array unit is divided into a horizontally arranged upper electrode array and a lower electrode array from top to bottom, and both the upper electrode array and the lower electrode array include a plurality of knee joints distributed in an array between the femur and the tibia. Ionized capacitive pressure sensing electrodes at the inner and outer sides of the soft tissue, and the ion gel dielectric layer is laid between the upper electrode array and the lower electrode array.

Further, the positions of the ionized capacitive pressure sensing electrodes of the upper electrode array correspond one-to-one with the positions of the ionized capacitive pressure sensing electrodes of the lower electrode array. The ionized capacitive pressure sensing electrodes are sequentially connected by lines, and each group of longitudinal lines extends from the end of the upper electrode array to the upper electrode beam line. Capacitive pressure sensing electrodes are sequentially connected by lines, and each group of transverse lines extends from the end of the lower electrode array to a lower electrode harness line, the upper electrode harness line and the lower electrode harness line are respectively connected with the AC Op amp measurement circuit connections.

Further, the ionized capacitive pressure sensing array gasket module further includes a silica gel cover and a silica gel layer, and the upper electrode array, the ion gel dielectric layer and the lower electrode array are sequentially arranged in the top-to-bottom direction. In the silicone sleeve, the silicone layer is packaged on the silicone sleeve above the upper electrode array.

Further, the capacitor array signal acquisition and processing module further includes a main control unit, the AC operational amplifier measurement circuit includes a line selection unit, a signal amplification unit and a data acquisition unit, the line selection unit is connected to the upper electrode harness row and the lower electrode. The electrode bundle line is connected with lines, the signal output end of the data acquisition unit is connected with the signal input end of the main control unit, and the signal amplification unit is connected in series between the line selection unit and the data acquisition unit.

Further, the capacitor array signal acquisition and processing module also includes a wireless signal transmission unit, the signal input end of the wireless signal transmission unit is connected with the signal output unit of the main control unit, and the pressure distribution on both sides of the knee joint is The display module includes a wireless signal receiving unit.

Further, the main control unit is an ARM-based control processor, and the communication mode between the wireless signal transmitting unit and the wireless signal receiving unit is Bluetooth transmission.

Based on the above-mentioned knee joint replacement gap balance measurement system, the present invention provides a preparation method for preparing an ionized capacitive pressure sensing array gasket module, comprising:

According to the action area of the knee femoral prosthesis on the resin gasket, determine the shape, quantity and position distribution of the ionized capacitive pressure sensing electrodes, and design the wiring of the electrode array unit;

A laser engraving machine was used to prepare templates of corresponding sizes, and the upper electrode array and the lower electrode array were respectively prepared on the film based on the template;

The ion gel dielectric layer is prepared, the ion gel dielectric layer is placed between the upper electrode array and the lower electrode array, and the upper electrode array, the ion gel dielectric layer and the lower electrode array are encapsulated with silica gel to form a closed ion gel dielectric layer. Electric capacitive pressure sensing array;

Silicone gaskets are prepared by machining molds, and the ionized capacitive pressure sensing array is placed under the silicone gasket for system assembly to form an ionized capacitive pressure sensing array gasket module.

Further, the preparation method of the ion gel dielectric layer comprises:

Take 10g of PVA powder in a beaker, add 100g of deionized water, and perform magnetic stirring at 95°C until it dissolves;

When the temperature drops to 40°C, add 8 g of H ₃ PO ₄ solution with a concentration of 85%, and continue to stir to obtain H ₃ PO ₄ precursor solution;

Use a scraper coater to evenly scrape the H ₃ PO ₄ precursor solution on the sandpaper, and place the scraped H ₃ PO ₄ precursor solution in a constant temperature and humidity box with a temperature of 40°C and a relative humidity of 35% until it reaches After the water is evaporated, the formed ion gel film is peeled off from the gauze paper and cut into corresponding shapes to obtain the ion gel dielectric layer.

Based on the above-mentioned knee joint replacement gap balance measurement system, the present invention provides a measurement method, comprising:

According to the plurality of ionized capacitive pressure sensing electrodes distributed by the electrode array unit on both sides of the knee joint, the main control unit outputs an instruction and instructs the line selection unit to collect the capacitive array data at different angles, and convert the data into Voltage signal, the data acquisition unit sends the acquired capacitance array data after analog-to-digital conversion to the pressure distribution display module on both sides of the knee joint by means of wireless transmission for recording and processing.

The present invention has the following beneficial effects due to taking the above technical solutions:

By placing multiple ionized capacitive pressure sensing electrodes with ultra-high sensitivity on the inside and outside of the knee joint soft tissue between the femur and tibia, the pressure distribution on both sides can be accurately measured, where the ionized capacitance value is given by The area of the ion-electron interface formed after the contact between the electrode and the ionogel dielectric layer is determined. With the increase of pressure, the contact area of the two changes significantly, and the capacitance value can vary from tens of pF to μF, spanning five orders of magnitude, In order to achieve ultra-high sensitivity detection of pressure, it can provide accurate assessment for intraoperative pressure distribution measurement on both sides of the knee joint.

Description of drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are for the purpose of illustrating preferred embodiments only and are not to be considered limiting of the invention. The same reference numerals are used to refer to the same parts throughout the drawings. In the attached image:

FIG. 1 is a schematic block diagram of the overall structure of a knee joint replacement gap balance measurement system provided by an embodiment of the present invention.

2 is a schematic structural diagram of an ionized capacitive pressure sensing array gasket module of a knee joint replacement gap balance measurement system according to an embodiment of the present invention.

3 is a schematic diagram of a wiring structure of an upper electrode array and a lower electrode array of a knee joint replacement gap balance measurement system provided by an embodiment of the present invention.

4 is a schematic diagram of an installation structure of an ionized capacitive pressure sensing array gasket module of a knee joint replacement gap balance measurement system provided by an embodiment of the present invention.

The symbols in the accompanying drawings are indicated as follows:

1. Ionized capacitive pressure sensing array gasket module; 11. Ionized capacitive pressure sensing electrode; 12. Ion gel dielectric layer; 13. Upper electrode array; 14. Lower electrode array; 15. Silicone sleeve ; 16, silica gel layer; 2, capacitor array signal acquisition and processing module; 21, main control unit; 22, line selection unit; 23, signal amplification unit; 24, data acquisition unit; 25, wireless signal transmission unit; 3, knee joint Pressure distribution display module on both sides; 31. Wireless signal receiving unit.

Detailed ways

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present invention will be more thoroughly understood, and will fully convey the scope of the present invention to those skilled in the art.

In the traditional knee replacement gap balance measurement, the pressure change on the periphery of the gasket cannot be detected, resulting in inaccurate measurement of the local pressure on the knee joint contact surface. The invention provides a knee replacement gap balance measurement system, preparation method and measurement method , by placing multiple ionized capacitive pressure sensing electrodes with ultra-high sensitivity on the inside and outside of the knee joint soft tissue between the femur and tibia to accurately measure the pressure distribution on both sides, and based on the ionized capacitance The value is determined by the area of the ion-electron interface formed after the contact between the electrode and the ionogel dielectric layer, the contact area of the two changes significantly with increasing pressure, and the capacitance value can vary from tens of pF to μF, spanning five order of magnitude to achieve ultra-high sensitivity detection of pressure, which can provide an accurate assessment for intraoperative pressure distribution measurements on both sides of the knee joint.

The solution of the present invention will be described in detail below by way of examples.

Example

As shown in FIG. 1 , the present invention provides a knee joint replacement gap balance measurement system, including an ionized capacitive pressure sensing array gasket module 1 , a capacitive array signal acquisition and processing module 2 and a pressure distribution display module 3 on both sides of the knee joint , the specific settings are as follows:

As shown in FIG. 2 , the ionized capacitive pressure sensing array gasket module 1 includes an electrode array unit. The electrode array unit includes a plurality of ionized capacitive pressure sensing electrodes 11 arranged in an array according to the positions of the inner and outer sides of the knee joint soft tissue between the femur and the tibia, and the plurality of ionized capacitive pressure sensing electrodes 11 are in contact with each other. Ion gel dielectric layer 12 . The electrode array unit is divided into a horizontally arranged upper electrode array 13 and a lower electrode array 14 from top to bottom. Both the upper electrode array 13 and the lower electrode array 14 include a plurality of soft tissues of the knee joint distributed in an array between the femur and the tibia. The ionized capacitive pressure sensing electrodes 11 are located at the inner and outer sides, and the ion gel dielectric layer 12 is laid between the upper electrode array 13 and the lower electrode array 14 . The setting of this structure is mainly based on this scheme, the ionized capacitance value is determined by the area of the ion-electron interface formed after the contact between the electrode and the ion gel dielectric layer 12. As the pressure increases, the contact area between the two is determined. Significant changes, capacitance values can vary from tens of pF to μF, spanning five orders of magnitude, to achieve ultra-sensitive detection of pressure.

Further, as shown in FIG. 3 , the positions of the ionized capacitive pressure sensing electrodes 11 of the upper electrode array 13 correspond one-to-one with the positions of the ionized capacitive pressure sensing electrodes 11 of the lower electrode array 14 . Among them, the plurality of ionized capacitive pressure sensing electrodes 11 distributed longitudinally in the upper electrode array 13 are sequentially connected by lines, and each group of longitudinal lines extends from the end of the upper electrode array 13 to the upper electrode harness line; the lower electrode array A plurality of ionized capacitive pressure sensing electrodes 11 distributed laterally in 14 are connected in sequence by lines, and each group of lateral lines extends from the end of the lower electrode array 14 to a lower electrode harness row. Based on the arrangement of the structure, the upper electrode wire harness and the lower electrode wire harness are respectively connected to the capacitor array signal acquisition and processing module 2 in circuits. The upper electrode array 13 and the lower electrode array 14 are arranged in a crisscross pattern to obtain a variety of lines in different directions on the inside and outside of the knee joint soft tissue between the femur and the tibia, so as to facilitate the acquisition of the capacitance array signal acquisition and processing module 2 Capacitance array data at different angles on the inside and outside of the soft tissue of the knee between the femur and tibia. Wherein, as shown in FIG. 4 , the ionized capacitive pressure sensing array gasket module 1 is placed in the soft tissue of the knee joint between the femur and the tibia during use.

Further, the ionized capacitive pressure sensing array gasket module 1 further includes a silica gel cover 15 and a silica gel layer 16 . The upper electrode array 13 , the ion gel dielectric layer 12 and the lower electrode array 14 are sequentially arranged in the silicone sleeve 15 along the top-to-bottom direction. The silicone layer 16 is packaged on the silicone sleeve 15 above the upper electrode array 13 . Through the arrangement of this structure, the ionized capacitive pressure sensing array composed of the upper electrode array 13, the ion gel dielectric layer 12 and the lower electrode array 14 can be packaged, which is convenient for the ionized capacitive pressure sensing array gasket module. 1 for placement use.

As mentioned above, the capacitance array signal acquisition and processing module 2 includes an AC operational amplifier measurement circuit, which is connected to the electrode array unit circuit for collecting, measuring and analyzing the capacitance signals of a plurality of ionized capacitance pressure sensing electrodes 11 . . Specifically, the capacitor array signal acquisition and processing module 2 further includes a main control unit 21 , and the AC operational amplifier measurement circuit includes a line selection unit 22 , a signal amplification unit 23 and a data acquisition unit 24 . The line selection unit 22 is wired to the upper electrode harness bar and the lower electrode harness bar. The signal output terminal of the data acquisition unit 24 is connected to the signal input terminal of the main control unit 21 , and the signal amplification unit 23 is connected in series between the line selection unit 22 and the data acquisition unit 24 . Among them, the main control unit 21 is preferably an STM32, and is based on an ARM control processor, the signal amplification unit 23 is an operational amplifier, and the data acquisition unit 24 is a digital-to-analog converter. Through the setting of this structure, the main control unit 21 is used to output commands and instruct the line selection unit 22 to collect the capacitance array data at different angles, and convert them into voltage signals through the signal amplification unit 23. The data collection unit 24 processes the collected capacitance array data through After the analog-to-digital conversion, it is sent to the pressure distribution display module 3 on both sides of the knee joint through wireless transmission for recording and processing.

Further, the capacitor array signal acquisition and processing module 2 further includes a wireless signal transmission unit 25 . The signal input end of the wireless signal transmitting unit 25 is connected to the signal output unit of the main control unit 21 , and the pressure distribution display module 3 on both sides of the knee joint includes a wireless signal receiving unit 31 for communicating with the wireless signal transmitting unit 25 . The communication method between the wireless signal transmitting unit 25 and the wireless signal receiving unit 31 is preferably Bluetooth transmission.

In the present invention, a plurality of ionized capacitive pressure sensing electrodes 11 with ultra-high sensitivity are respectively placed on the inner and outer sides of the knee joint soft tissue between the femur and the tibia, and the pressure distribution on both sides is accurately measured. The capacitance value is determined by the area of the ion-electron interface formed after the electrode and the ion gel dielectric layer 12 are in contact. Five orders of magnitude to achieve ultra-high sensitivity detection of pressure, which can provide an accurate assessment for intraoperative pressure distribution measurements on both sides of the knee joint.

Based on the above-mentioned knee joint replacement gap balance measurement system, the present invention also provides a preparation method for preparing the ionized capacitive pressure sensing array gasket module 1, comprising:

According to the action area of the knee femoral prosthesis on the resin gasket, determine the shape, quantity and position distribution of the ionized capacitive pressure sensing electrodes 11, and design the wiring of the electrode array unit;

A laser engraving machine is used to prepare a template of the corresponding size. The template is preferably a corresponding metal mask or a screen printing template of the corresponding size. Based on the template, the upper electrode array and the lower electrode array are prepared on a PET film or PI film with a thickness of 100um, respectively. Among them, the metal electrode is a 100nm Au film or a 10um silk-screened Ag film;

The ion gel dielectric layer is prepared, the ion gel dielectric layer is placed between the upper electrode array and the lower electrode array, and the upper electrode array, the ion gel dielectric layer and the lower electrode array are encapsulated with silica gel to form a closed ion gel dielectric layer. Electric capacitive pressure sensing array;

The silicone gasket is prepared by machining the mold, and the ionized capacitive pressure sensing array is placed under the silicone gasket for system assembly to form the ionized capacitive pressure sensing array gasket module, wherein the machining mold is based on the knee joint femur. Silicone spacer metal machined mold designed for the characteristics of the tibia.

Further, the preparation method of the ion gel dielectric layer comprises:

Take 10g of PVA powder in a beaker, add 100g of deionized water, and conduct magnetic stirring for 3 hours at 95°C until it dissolves;

When the temperature drops to 40 °C, add 8 g of H3PO4 solution with a concentration of 85%, and continue to stir for one hour to obtain the H3PO4 precursor solution;

Use a scraper coater to evenly scrape a 750um thick H3PO4 precursor on the sandpaper, and place the scraped H3PO4 precursor in a constant temperature and humidity box with a temperature of 40°C and a relative humidity of 35% for 24 hours, until After most of its water is evaporated, the formed ion gel film is peeled off from the gauze paper and cut into corresponding shapes to obtain the ion gel dielectric layer.

Based on the above-mentioned knee replacement gap balance measurement system, the present invention also provides a measurement method, comprising:

According to the plurality of ionized capacitive pressure sensing electrodes 11 distributed by the electrode array unit on both sides of the knee joint, the main control unit 21 outputs an instruction and instructs the line selection unit 22 to collect the capacitive array data at different angles, and through the signal amplification unit 23 Converted into a voltage signal, the data acquisition unit 24 performs analog-to-digital conversion on the collected capacitance array data, and sends it to the pressure distribution display module 3 on both sides of the knee joint by means of wireless transmission for recording and processing.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that it can still be The technical solutions described in the foregoing embodiments are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (8)

1. A knee replacement gap balance measurement system, comprising:

the ionization type capacitance pressure sensing array gasket module comprises an electrode array unit, wherein the electrode array unit comprises a plurality of ionization type capacitance pressure sensing electrodes which are distributed in an array mode according to the positions of the inner side and the outer side of knee joint soft tissue between a femur and a tibia, and an ionic gel dielectric layer is arranged on the plurality of ionization type capacitance pressure sensing electrodes in a contact mode;

the electrode array unit is sequentially divided into an upper electrode array and a lower electrode array which are horizontally arranged from top to bottom, the upper electrode array and the lower electrode array respectively comprise a plurality of ionization type capacitance pressure sensing electrodes which are distributed in an array manner at the inner side and the outer side of knee joint soft tissue between femur and tibia, an ion gel dielectric layer is laid between the upper electrode array and the lower electrode array, the positions of the ionization type capacitance pressure sensing electrodes of the upper electrode array correspond to the positions of the ionization type capacitance pressure sensing electrodes of the lower electrode array one by one, the ionization type capacitance pressure sensing electrodes which are longitudinally distributed in the upper electrode array are sequentially connected through a circuit, an upper electrode bundle line row extends from the tail end of the upper electrode array through each group of longitudinal circuits, and the ionization type capacitance pressure sensing electrodes which are transversely distributed in the lower electrode array are sequentially connected through the circuit, each group of transverse lines extends out of a lower electrode wiring harness row from the tail end of the lower electrode array, and the upper electrode wiring harness row and the lower electrode wiring harness row are respectively connected with the alternating current operational amplifier measuring circuit;

the capacitive array signal acquisition and processing module comprises an alternating current operational amplifier measuring circuit, and the alternating current operational amplifier measuring circuit is connected with the electrode array unit circuit and is used for acquiring, measuring and analyzing capacitance signals of a plurality of off-current capacitive pressure sensing electrodes;

and the knee joint two-side pressure distribution display module is in communication connection with the capacitance array signal acquisition and processing module and is used for acquiring and displaying the capacitance signals after analysis and processing.

2. The knee replacement gap balance measurement system of claim 1, wherein: the ionization type capacitive pressure sensing array gasket module further comprises a silica gel sleeve and a silica gel layer, the upper electrode array, the ionic gel dielectric layer and the lower electrode array are sequentially arranged in the silica gel sleeve along the direction from top to bottom, and the silica gel layer is encapsulated above the upper electrode array on the silica gel sleeve.

3. The knee replacement gap balance measurement system of claim 1, wherein: the capacitive array signal acquisition and processing module further comprises a main control unit, the alternating current operational amplifier measuring circuit comprises a line selection unit, a signal amplification unit and a data acquisition unit, the line selection unit is connected with an upper electrode bunch row and a lower electrode bunch row line, a signal output end of the data acquisition unit is connected with a signal input end of the main control unit, and the signal amplification unit is connected in series with the line selection unit and the data acquisition unit.

4. The knee replacement gap balance measurement system of claim 3, wherein: the capacitance array signal acquisition and processing module further comprises a wireless signal transmitting unit, the signal input end of the wireless signal transmitting unit is connected with the signal output unit of the main control unit, and the pressure distribution display modules on the two sides of the knee joint comprise wireless signal receiving units.

5. The knee replacement gap balance measurement system of claim 4, wherein: the main control unit is an ARM-based control processor, and the communication mode of the wireless signal transmitting unit and the wireless signal receiving unit is Bluetooth transmission.

6. A method for manufacturing an ionospheric capacitive pressure sensing array pad module for use in the knee replacement gap balance measurement system of any of claims 1-5, comprising:

determining the shape, the number and the position distribution of the ionization type capacitance pressure sensing electrodes according to the action area of the knee joint femoral prosthesis on the resin gasket, and designing the wiring of the electrode array unit;

preparing templates with corresponding sizes by adopting a laser engraving machine, and respectively preparing an upper electrode array and a lower electrode array on the PET film or the PI film based on the templates;

preparing an ionic gel dielectric layer, placing the ionic gel dielectric layer between an upper electrode array and a lower electrode array, and packaging the upper electrode array, the ionic gel dielectric layer and the lower electrode array by adopting silica gel to form a closed ionic capacitance pressure sensing array;

and preparing a silica gel gasket by processing a mould, and placing the ionization type capacitance pressure sensing array under the silica gel gasket for system assembly to form an ionization type capacitance pressure sensing array gasket module.

7. A method according to claim 6, wherein the ionic gel dielectric layer is prepared by a method comprising:

taking 10g of PVA powder in a beaker, adding 100g of deionized water, and carrying out magnetic stirring under the condition of heat preservation at 95 ℃ until the PVA powder is dissolved;

when the temperature is reduced to 40 ℃, 8g of H3PO4 solution with the concentration of 85% is added, and the mixture is continuously stirred to obtain H3PO4 precursor solution;

uniformly blade-coating an H3PO4 precursor solution on sand paper by using a blade coater, placing the blade-coated H3PO4 precursor solution in a constant-temperature and constant-humidity box with the temperature of 40 ℃ and the relative humidity of 35%, peeling the formed ionic gel film from the gauze paper after the moisture of the ionic gel film is evaporated, and cutting the ionic gel film into a corresponding shape to obtain the ionic gel dielectric layer.

8. A measurement method based on the knee replacement gap balance measurement system according to any one of claims 3 to 5, comprising:

according to a plurality of ionization type capacitance pressure sensing electrodes distributed on two sides of the knee joint through the electrode array units, the main control unit outputs instructions and commands the circuit selection unit to collect capacitance array data at different angles and converts the capacitance array data into voltage signals through the signal amplification unit, and the data collection unit sends the collected capacitance array data to the pressure distribution display modules on two sides of the knee joint in a wireless transmission mode to record and process the collected capacitance array data after analog-to-digital conversion.

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