CN114848245B - Knee joint replacement gap balance measuring system, preparation method and measuring method - Google Patents
Knee joint replacement gap balance measuring system, preparation method and measuring method Download PDFInfo
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
- A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
- A61F2/02—Prostheses implantable into the body
- A61F2/30—Joints
- A61F2/46—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor
- A61F2/4657—Measuring instruments used for implanting artificial joints
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
- A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
- A61F2/02—Prostheses implantable into the body
- A61F2/30—Joints
- A61F2/46—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor
- A61F2/4603—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for insertion or extraction of endoprosthetic joints or of accessories thereof
- A61F2/461—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor for insertion or extraction of endoprosthetic joints or of accessories thereof of knees
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/14—Measuring force or stress, in general by measuring variations in capacitance or inductance of electrical elements, e.g. by measuring variations of frequency of electrical oscillators
- G01L1/142—Measuring force or stress, in general by measuring variations in capacitance or inductance of electrical elements, e.g. by measuring variations of frequency of electrical oscillators using capacitors
- G01L1/146—Measuring force or stress, in general by measuring variations in capacitance or inductance of electrical elements, e.g. by measuring variations of frequency of electrical oscillators using capacitors for measuring force distributions, e.g. using force arrays
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
- A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
- A61F2/02—Prostheses implantable into the body
- A61F2/30—Joints
- A61F2/46—Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor
- A61F2/4657—Measuring instruments used for implanting artificial joints
- A61F2002/4666—Measuring instruments used for implanting artificial joints for measuring force, pressure or mechanical tension
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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
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
Knee Osteoarthritis (OA) is a common chronic degenerative disease of the joints. For patients with severe osteoarthropathy in the middle and advanced stages, artificial Total Knee Arthroplasty (TKA) is the first choice for surgical treatment. The TKA operation can effectively relieve pain of osteoarthritis patients and improve knee joint function.
Soft tissue balance and lower limb force line correction are two most important technical links in the TKA operation. Compared with the correction of lower limb force lines, the knee joint soft tissue balance in the operation is lack of an accurate quantitative judgment method at present. Soft tissue imbalance may result in knee joint pain, limited function, joint instability, prosthetic loosening, and poor patellar tracking, all of which are important causes of revision of the knee joint. The traditional soft tissue balancing technology mainly comprises a measurement osteotomy technology (measured recovery) and a gap balancing technology (gap balancing), the balance of the soft tissue under the two technologies depends on the experience and subjective judgment of a main surgeon, and objective data feedback under different knee bending angles is lacked. Therefore, designing a measuring tool that can be used in surgery and accurately evaluate the soft tissue balance at each knee flexion angle is an important issue in the TKA research field.
At present, a plurality of units and companies at home and abroad research the pressure measuring system, and the Verasense system at home and abroad and the Balansense system at home and in China are the most representative. In recent years, the Verasense system has the advantages of simple operation and high quantification degree, and is widely applied in European and American countries, so that the accuracy of the TKA operation is effectively improved. However, the Verasense system only measures pressure by using a single resistance type pressure sensor at the center of the pressure measuring gasket, can only provide the pressure change condition of the central load bearing area of the inner and outer compartments at the center of the knee joint, and cannot reflect the pressure distribution information of the whole surfaces of the inner and outer compartments. The Balansense system which is easy to take medical care in China estimates the pressure of the surfaces of inner and outer compartments by means of three commercial Honeywell pressure sensor chips on one side, the balance of soft tissue adjustment can be further improved, but the pressure change of the periphery of the gasket cannot be detected, obvious errors exist in the edge of an osteotomy plane for stress generation, and the part is often the most serious part of the gasket in the process of TKA revision. Therefore, only by extracting the pressure distribution characteristics of the whole surface of the inner side and the outer side of the knee joint soft tissue, the balance model of the inner side and the outer side ligaments can be reasonably established, and the accurate and efficient regulation and control of soft tissue balance in the operation can be realized.
Disclosure of Invention
The invention aims to provide a knee joint replacement gap balance measuring system, a preparation method and a measuring method, and aims to solve the problem that the measurement of the local pressure of a knee joint contact surface in the prior art is not accurate.
In order to achieve the purpose, the invention adopts the following technical scheme:
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 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.
Furthermore, 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 the positions of the inner side and the outer side of knee joint soft tissue between femur and tibia in an array mode, and the ion gel dielectric layer is laid between the upper electrode array and the lower electrode array.
Furthermore, 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, wherein a plurality of ionization type capacitance pressure sensing electrodes longitudinally distributed in the upper electrode array are sequentially connected through lines, each group of longitudinal lines extends out of an upper electrode beam line row from the tail end of the upper electrode array, a plurality of ionization type capacitance pressure sensing electrodes transversely distributed in the lower electrode array are sequentially connected through lines, each group of transverse lines extends out of a lower electrode beam line row from the tail end of the lower electrode array, and the upper electrode beam line row and the lower electrode beam line row are respectively connected with the alternating current operational amplifier measuring circuit.
Furthermore, 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 ion gel dielectric layer and the lower electrode array are sequentially arranged in the silica gel sleeve from top to bottom, and the silica gel layer is encapsulated on the silica gel sleeve above the upper electrode array.
Furthermore, the capacitance array signal acquisition 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 the upper electrode bunch row and the lower electrode bunch row, 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.
Furthermore, the capacitance array signal acquisition processing module further comprises a wireless signal transmitting unit, a signal input end of the wireless signal transmitting unit is connected with a signal output unit of the main control unit, and the pressure distribution display modules on two sides of the knee joint comprise wireless signal receiving units.
Furthermore, 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.
Based on the knee joint replacement gap balance measurement system, the invention provides a preparation method for preparing an ionization type capacitance pressure sensing array gasket module, which comprises the following steps:
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 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.
Further, the preparation method of the ionic gel dielectric layer comprises the following steps:
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 had dropped to 40 ℃, 8g of H at 85% concentration was added 3 PO 4 The solution is stirred continuously to obtain H 3 PO 4 A precursor solution;
evenly coating H on sand paper by using a coating machine 3 PO 4 Precursor solution, and blade-coated H 3 PO 4 And placing the precursor solution in a constant-temperature and constant-humidity box with the temperature of 40 ℃ and the relative humidity of 35%, stripping the formed ionic gel film from the gauze paper after the moisture of the precursor solution is evaporated, and cutting the gauze paper into a corresponding shape to obtain the ionic gel dielectric layer.
Based on the knee joint replacement gap balance measuring system, the invention provides a measuring method, which comprises the following steps:
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.
Due to the adoption of the technical scheme, the invention has the following beneficial effects:
a plurality of ionization type capacitance pressure sensing electrodes with ultrahigh sensitivity are respectively placed on the inner side and the outer side of knee joint soft tissue between a femur and a tibia, and pressure distribution conditions on two sides are accurately measured, wherein an ionization type capacitance value is determined by the area of an ion-electron interface formed after the electrodes are contacted with an ionic gel dielectric layer, along with the increase of pressure, the contact area of the two electrodes is obviously changed, the capacitance value can be changed to mu F from dozens of pF, five orders of magnitude are spanned, so that ultrahigh sensitivity detection of pressure is realized, and accurate evaluation can be provided for pressure distribution measurement on two sides of a knee joint in an operation.
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 only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Like reference numerals refer to like parts throughout the drawings. In the drawings:
fig. 1 is a schematic block diagram of an overall structure of a knee joint replacement gap balance measurement system according to an embodiment of the present invention.
Fig. 2 is a schematic structural diagram of an ionization type capacitive pressure sensing array gasket module of a knee joint replacement gap balance measurement system according to an embodiment of the present invention.
Fig. 3 is a schematic diagram of the wiring structures of the upper electrode array and the lower electrode array of the knee joint replacement gap balance measuring system according to an embodiment of the present invention.
Fig. 4 is a schematic view of an installation structure of an ionization type capacitive pressure sensing array pad module of a knee joint replacement gap balance measurement system according to an embodiment of the present invention.
In the drawings, the reference numerals denote the following:
1. an off-axis capacitive pressure sensing array gasket module; 11. an ionization type capacitive pressure sensing electrode; 12. an ionic gel dielectric layer; 13. an upper electrode array; 14. a lower electrode array; 15. a silica gel sleeve; 16. a silica gel layer; 2. a capacitance array signal acquisition processing module; 21. a main control unit; 22. a line selection unit; 23. a signal amplification unit; 24. a data acquisition unit; 25. a wireless signal transmitting unit; 3. a pressure distribution display module at two sides of the knee joint; 31. a wireless signal receiving unit.
Detailed Description
Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
Because the pressure change at the periphery of the gasket can not be detected in the gap balance measurement of the traditional knee joint replacement, the invention provides a knee joint replacement gap balance measurement system, a preparation method and a measurement method, a plurality of ionization type capacitance pressure sensing electrodes with ultrahigh sensitivity are respectively arranged at the inner side and the outer side of the knee joint soft tissue between the femur and the tibia, so as to accurately measure the pressure distribution conditions on two sides, and the ionization type capacitance value is determined by the area of an ion-electron interface formed after the electrode is contacted with the ionic gel dielectric layer, the contact area of the electrode and the ionic gel dielectric layer is obviously changed along with the increase of the pressure, the capacitance value can be changed from tens of pF to muF, spans five orders of magnitude, the pressure detection device can realize the ultrahigh sensitivity detection of the pressure and provide accurate evaluation for the measurement of the pressure distribution at two sides of the knee joint in the operation.
The embodiment of the present invention will be described in detail by examples.
Examples
As shown in fig. 1, the present invention provides a knee joint replacement gap balance measurement system, which includes an ionization type capacitance pressure sensing array gasket module 1, a capacitance array signal acquisition processing module 2, and a knee joint two-side pressure distribution display module 3, and is specifically configured as follows:
as shown in fig. 2, the off-axis capacitive pressure sensing array pad module 1 includes an electrode array unit. The electrode array unit comprises a plurality of ionization type capacitance pressure sensing electrodes 11 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 femur and tibia, and an ion gel dielectric layer 12 is arranged on the plurality of ionization type capacitance pressure sensing electrodes 11 in a contact mode. The electrode array unit is sequentially divided into an upper electrode array 13 and a lower electrode array 14 which are horizontally arranged from top to bottom, the upper electrode array 13 and the lower electrode array 14 both comprise a plurality of ionization type capacitance pressure sensing electrodes 11 which are distributed on the inner side and the outer side of knee joint soft tissue between femur and tibia in an array mode, and an ionic gel dielectric layer 12 is laid between the upper electrode array 13 and the lower electrode array 14. The structure is mainly arranged on the basis that in the scheme, the ionization type capacitance value is determined by the area of an ion-electron interface formed after the electrode is contacted with the ionic gel dielectric layer 12, the contact area of the electrode and the ionic gel dielectric layer is obviously changed along with the increase of pressure, the capacitance value can be changed from dozens of pF to muF and spans five orders of magnitude, and therefore the ultrahigh-sensitivity detection of the pressure is realized.
Further, as shown in fig. 3, the positions of the respective ionization type capacitive pressure sensing electrodes 11 of the upper electrode array 13 correspond to the positions of the respective ionization type capacitive pressure sensing electrodes 11 of the lower electrode array 14 one by one. A plurality of ionization type capacitance pressure sensing electrodes 11 longitudinally distributed in the upper electrode array 13 are sequentially connected through circuits, and each group of longitudinal circuits extends out of an upper electrode bundle line row at the tail end of the upper electrode array 13; the plurality of ionization type capacitive pressure sensing electrodes 11 distributed in the lower electrode array 14 in the transverse direction are connected in sequence through circuits, and each group of transverse circuits extend out of a lower electrode bundle line row at the tail end of the lower electrode array 14. Based on the structure, the upper electrode wire harness row and the lower electrode wire harness row are respectively connected with the capacitor array signal acquisition processing module 2 through circuits. Through the crisscross wiring mode of the upper electrode array 13 and the lower electrode array 14, various circuits in different directions on the inner side and the outer side of the knee joint soft tissue between the femur and the tibia are obtained, so that the capacitance array signal acquisition and processing module 2 can conveniently acquire capacitance array data at different angles on the inner side and the outer side of the knee joint soft tissue between the femur and the tibia. In which the ionospheric capacitive pressure sensing array shim module 1 is placed in the soft tissue of the knee joint between the femur and tibia in use, as shown in figure 4.
Further, the off-current capacitive pressure sensing array gasket module 1 further includes a silicone sleeve 15 and a silicone layer 16. The upper electrode array 13, the ionic gel dielectric layer 12 and the lower electrode array 14 are sequentially arranged in the silica gel sleeve 15 from top to bottom, and the silica gel layer 16 is encapsulated on the silica gel sleeve 15 above the upper electrode array 13. Through the arrangement of the structure, the ionization type capacitance pressure sensing array consisting of the upper electrode array 13, the ionic gel dielectric layer 12 and the lower electrode array 14 is packaged, and the gasket module 1 of the ionization type capacitance pressure sensing array is convenient to place and use.
As described above, the capacitance array signal acquisition processing module 2 includes the ac operational amplifier measuring circuit, and the ac operational amplifier measuring circuit is connected to the electrode array unit circuit and is used for acquiring, measuring and analyzing the capacitance signals of the plurality of off-type capacitance pressure sensing electrodes 11. Specifically, the capacitive array signal acquisition and processing module 2 further includes a main control unit 21, and the ac operational amplifier measuring circuit includes a line selection unit 22, a signal amplification unit 23, and a data acquisition unit 24. The line selection unit 22 is connected to the upper electrode harness row and the lower electrode harness row. The signal output end of the data acquisition unit 24 is connected with the signal input end 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. The preferred model of the main control unit 21 is STM32, and based on the control processor of ARM, 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, utilize main control unit 21 output instruction and instruct circuit selection unit 22 to gather the capacitance array data at different angles to convert voltage signal into through signal amplification unit 23, data acquisition unit 24 sends the capacitance array data of gathering after analog-to-digital conversion to knee joint both sides pressure distribution display module 3 through wireless transmission's mode and takes notes and handle.
Further, the capacitive array signal acquisition and processing module 2 further includes a wireless signal transmitting unit 25. The signal input end of the wireless signal transmitting unit 25 is connected with the signal output unit of the main control unit 21, and the pressure distribution display module 3 on both sides of the knee joint comprises 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.
According to the invention, a plurality of ionization type capacitance pressure sensing electrodes 11 with ultrahigh sensitivity are respectively arranged on the inner side and the outer side of knee joint soft tissue between femur and tibia, and pressure distribution conditions on the two sides are accurately measured, wherein an ionization type capacitance value is determined by the area of an ion-electron interface formed after the electrodes are contacted with an ion gel dielectric layer 12, along with the increase of pressure, the contact area of the two electrodes is obviously changed, the capacitance value can be changed from tens of pF to muF and spans five orders of magnitude, so that ultrahigh sensitivity detection of pressure is realized, and accurate evaluation can be provided for pressure distribution measurement on the two sides of the knee joint in operation.
Based on the knee joint replacement gap balance measurement system, the invention also provides a preparation method for preparing the ionization type capacitance pressure sensing array gasket module 1, which comprises the following steps:
determining the shape, the number and the position distribution of the ionization type capacitance pressure sensing electrodes 11 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 a template with a corresponding size by using a laser engraving machine, wherein the template is preferably a corresponding metal mask plate or a screen printing template with a corresponding size, and respectively preparing an upper electrode array and a lower electrode array on a PET (polyethylene terephthalate) film or PI (polyimide) film with the thickness of 100um based on the template, wherein the metal electrode is a 100nm Au film or a 10um screen printing Ag film;
preparing an ionic gel dielectric layer, placing the ionic gel dielectric layer between the upper electrode array and the 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;
preparing a silica gel gasket by a processing 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, wherein the processing mould is a silica gel gasket metal machining mould designed according to the characteristics of knee joint thighbone and shinbone.
Further, the preparation method of the ionic gel dielectric layer comprises the following steps:
taking 10g of PVA powder in a beaker, adding 100g of deionized water, and magnetically stirring for three hours at the temperature of 95 ℃ until the PVA powder is dissolved;
when the temperature is reduced to 40 ℃, 8g of H3PO4 solution with the concentration of 85 percent is added, and the stirring is continued for one hour to obtain H3PO4 precursor solution;
uniformly blade-coating an H3PO4 precursor solution with the thickness of 750 mu m 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% for twenty-four hours until most of water is evaporated, peeling the formed ionic gel film from the sand paper, and cutting the ionic gel film into corresponding shapes to obtain the ionic gel dielectric layer.
Based on the knee joint replacement gap balance measuring system, the invention also provides a measuring method, which comprises the following steps:
according to the plurality of ionization type capacitance pressure sensing electrodes 11 distributed on two sides of the knee joint through the electrode array units, the main control unit 21 outputs instructions and commands the circuit selection unit 22 to collect capacitance array data at different angles, the capacitance array data are converted into voltage signals through the signal amplification unit 23, and the data collection unit 24 sends the collected capacitance array data to the pressure distribution display modules 3 on two sides of the knee joint in a wireless transmission mode to be recorded and processed after analog-to-digital conversion.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding 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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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106768508A (en) * | 2016-12-02 | 2017-05-31 | 西安交通大学 | A kind of gel capacitance type sensor and method for measuring plantar pressure and dynamic change |
| CN107242907A (en) * | 2017-07-26 | 2017-10-13 | 北京易迈医疗科技有限公司 | Knee joint unicondylar pressure measuring device and system |
| CN110432578A (en) * | 2019-05-13 | 2019-11-12 | 潘挺睿 | The intelligent shoe of foot health and fitness information and motion state is monitored based on pressure sensing array |
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| US7849751B2 (en) * | 2005-02-15 | 2010-12-14 | Clemson University Research Foundation | Contact sensors and methods for making same |
| US9259179B2 (en) * | 2012-02-27 | 2016-02-16 | Orthosensor Inc. | Prosthetic knee joint measurement system including energy harvesting and method therefor |
| WO2018119360A1 (en) * | 2016-12-22 | 2018-06-28 | Orthosensor Inc. | Surgical apparatus to support installation of a prosthetic component and method therefore |
| WO2022072977A1 (en) * | 2020-09-30 | 2022-04-07 | DePuy Synthes Products, Inc. | Surgical instrument system for total knee replacement with force sensor adapters and force sensor systems |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106768508A (en) * | 2016-12-02 | 2017-05-31 | 西安交通大学 | A kind of gel capacitance type sensor and method for measuring plantar pressure and dynamic change |
| CN107242907A (en) * | 2017-07-26 | 2017-10-13 | 北京易迈医疗科技有限公司 | Knee joint unicondylar pressure measuring device and system |
| CN110432578A (en) * | 2019-05-13 | 2019-11-12 | 潘挺睿 | The intelligent shoe of foot health and fitness information and motion state is monitored based on pressure sensing array |
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