A method for applying a flexible stress sensor to an orthopedic bone plate

Abstract

The application discloses a method for applying a flexible stress sensor to an orthopedic bone plate, relates to the technical field of bioengineering, and provides a bone plate, a biodegradable plastic substrate, and a sensor sensitive layer substrate; the biodegradable plastic substrate and the sensor sensitive layer substrate are symmetrically arranged in double layers; a liquid metal layer is printed between the double-layer sensor sensitive layer substrates, and the liquid metal layer is symmetrically arranged in double layers; a transition electrode is arranged on the double-layer liquid metal layer; a conductive ink layer is printed between the double-layer liquid metal layers; an interface is connected to the transition electrode; thus, a primary encapsulated stress sensor is formed; the primary encapsulated stress sensor is installed between the double-layer biodegradable plastic substrates to form a completely encapsulated stress sensor; and the surface of the bone plate is uniformly coated with metal glue, and the completely encapsulated stress sensor is attached to the surface of the bone plate.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of bioengineering technology, in particular to a method for applying a flexible stress sensor to an orthopedic bone plate. BACKGROUND

[0002] Stress sensors are widely used in the fields of industry, construction and medicine. They can directly show the stress distribution and stress changes of materials and are one of the necessary sensors in many fields. In the existing medical field, stress sensors are used to monitor the stress distribution of human tissues to assist in diagnosis and treatment. In the field of orthopedics, the application of stress sensors is less common. In the treatment of fractures, if the stress state of the fracture end can be detected, it will greatly help the treatment of fractures. However, there is no product in the prior art that applies a flexible stress sensor to an orthopedic bone plate. SUMMARY

[0003] The technical problem to be solved by the present application is to provide a method for applying a flexible stress sensor to an orthopedic bone plate, which solves the problem that the prior art does not have a stress sensor applied to orthopedic treatment.

[0004] TECHNICAL SOLUTION

[0005] To solve the above problems, the technical solution provided by the present application is:

[0006] A method for applying a flexible stress sensor to an orthopedic bone plate, comprising

[0007] providing a bone plate, a biodegradable plastic substrate, and a sensor sensitive layer substrate;

[0008] The biodegradable plastic substrate and the sensor sensitive layer substrate are symmetrically arranged in double layers;

[0009] A liquid metal layer is printed between the double-layer sensor sensitive layer substrates, and the liquid metal layer is symmetrically arranged in double layers; a transition electrode is arranged on the double-layer liquid metal layer;

[0010] A conductive ink layer is printed between the double-layer liquid metal layers;

[0011] The transition electrode is connected to an interface;

[0012] A preliminary encapsulated stress sensor is formed in this way;

[0013] The preliminary encapsulated sensor is installed between the double-layer biodegradable plastic substrates to form a completely encapsulated stress sensor;

[0014] The surface of the bone plate is uniformly coated with metal glue, and the completely encapsulated stress sensor is attached to the surface of the bone plate;

[0015] The interface outer end is connected with the enameled wire, and the wire is fixed to the end of the bone plate by using strong glue.

[0016] The interface part and exposed part of the fully encapsulated stress sensor mounted on the bone plate are encapsulated and solidified by using silica gel.

[0017] Further, the sensor sensitive layer substrate is made of electrostatic spinning.

[0018] Further, the electrostatic spinning is prepared into a nanofiber membrane as the sensor sensitive layer substrate.

[0019] Further, the liquid metal layer is printed on the sensor sensitive layer substrate by cooperating with a template.

[0020] Further, the conductive ink layer is printed on the sensor sensitive layer substrate by cooperating with a template.

[0021] Further, the interface is a PI-Cu interface, and the transition electrode is a Cu-PI electrode.

[0022] Further, the fully encapsulated stress sensor is further punched, and the hole on the sensor corresponds to the hole on the bone plate.

[0023] The application further provides a bone plate with a flexible stress sensor, comprising a bone plate and a fully encapsulated stress sensor fixed on the bone plate.

[0024] The bone plate is a rectangular long strip structure made of solid metal material, and a plurality of uniformly distributed insertion holes are arranged on the bone plate.

[0025] Further, the fully encapsulated stress sensor is a multilayer composite structure, and the multilayer composite structure of the fully encapsulated stress sensor is a biodegradable plastic substrate, a sensor sensitive layer substrate, a liquid metal layer, a conductive ink layer, a liquid metal layer, a sensor sensitive layer substrate, and a biodegradable plastic substrate, and a transition electrode is arranged on the symmetrically arranged double-layer liquid metal layer.

[0026] Further, the fully encapsulated stress sensor is mounted on the bone plate, and the structure is sequentially arranged from bottom to top as the bone plate, the metal glue, the fully encapsulated stress sensor, and the silica gel.

[0027] Beneficial effects

[0028] Compared with the prior art, the technical solution provided by this invention has the following advantages:

[0029] The technical solution provided by this invention offers a method that combines a flexible stress sensor with a carrier for implantation within the body. By integrating the bone plate and the stress sensor into a single structure, it enables the detection of stress changes at the fracture ends during fracture treatment, facilitating timely and necessary medical monitoring. By designing a novel bone plate for use with the flexible stress sensor, the bone plate provides the sensor with more precise resolution, enabling real-time monitoring and transmission of mechanical data at the fracture ends, thus providing important reference for clinical treatment. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the packaged cross-section of the stress sensor according to Embodiment 1 of the present invention;

[0031] Figure 2 This is a top view of the stress sensor of Embodiment 1 of the present invention mounted on the bone plate;

[0032] Figure 3 This is a top view of the bone plate of Embodiment 2 of the present invention;

[0033] Figure 4 This is a cross-sectional view of the bone plate of Embodiment 2 of the present invention. Detailed Implementation

[0034] To make the technical solution of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] Example 1

[0036] Combined with appendix Figures 1-4 A method for applying a flexible stress sensor 20 to an orthopedic bone plate 10. The orthopedic bone plate 10 with stress sensor 20 made according to this method is composed of layers made of different materials with different functions. The stress sensor 20 is formed by regularly composing several layers, and then the sensor is fixedly installed on the bone plate 10 to form an orthopedic bone plate 10 with stress sensor 20.

[0037] The stress sensor 20 is composed of multiple functional layers. The stress sensor 20 includes a sensor sensitive layer substrate 22, a liquid metal layer 21, a conductive ink layer 23, and a transition electrode 26 connected to the liquid metal layer 21.

[0038] The stress sensor 20 is preferably a resistance stress sensor. During the fracture treatment, the conductive ink layer 23 deforms with the bone plate, thereby changing the resistance of the conductive ink layer 23. The stress sensor 20 transmits the stress change of the biological bone in the form of an electrical signal during the fracture treatment by further changing the resistance of the conductive ink layer 23.

[0039] The sensor sensitive layer substrate 22 and the liquid metal layer 21 constituting the sensor are both symmetrically arranged in double layers. The liquid metal layer 21 and the sensor sensitive layer substrate 22 are sequentially coated on the front and back surfaces of the conductive ink layer 23 to form the composite stress sensor 20.

[0040] In actual installation and production, for the convenience of processing and to improve the product qualification rate, the sensor sensitive layer substrate 22 is selected as the basis for the production of the stress sensor 20. The production steps are as follows:

[0041] The sensor sensitive layer substrate 22 is prepared. The sensor sensitive layer substrate 22 is made of a nanofiber membrane produced by electrospinning. The nanofiber membrane can better form a patterned pattern for the liquid metal layer 21 and the conductive ink layer 23, thereby serving as a high-quality substrate selection for the stress sensor sensitive layer.

[0042] Therefore, the electrospinning is used to make the nanofiber membrane to form the sensor sensitive layer substrate 22.

[0043] The liquid metal layer 21 and the conductive ink layer 23 are sequentially printed on the surface of the sensor sensitive layer substrate 22. The liquid metal layer 21 and the conductive ink layer 23 are mainly printed on the surface of the sensor sensitive layer substrate 22 through a pre-prepared printing template. The printing template of the liquid metal layer 21 and the conductive ink layer 23 is designed according to the structure design of the stress sensor 20. The raw materials of the liquid metal and the conductive ink are respectively sprayed on the sensor sensitive layer substrate 22 to form the liquid metal layer 21 and the conductive ink layer 23 by using the liquid metal template and the conductive ink template.

[0044] The liquid metal layer is used to encapsulate the conductive ink and conduct electrical signals. The conductive ink layer is the core layer of the sensor. The deformation of the conductive ink layer will cause the resistance to change accordingly, thereby providing the sensor function.

[0045] At the same time, since the conductive ink layer 23 is located in the central position of the stress sensor 20, the sensor sensitive layer substrate 22 and the liquid metal layer 21 are symmetrically arranged on the front and back surfaces of the conductive ink layer 23. Therefore, a sensor sensitive layer substrate 22 with a liquid metal layer 21 on one surface needs to be prepared repeatedly.

[0046] The second prepared sensor sensitive layer substrate 22 with liquid metal layer 21 is arranged opposite to the conductive ink layer 23 on the sensor sensitive layer substrate 22 prepared initially, and at this time, the stress sensor 20 with the conductive ink layer in the middle position is formed.

[0047] Meanwhile, the transition electrode 26 is arranged on the same side of the liquid metal layer 21 on the conductive ink layer 23 on the front and back sides of the liquid metal layer 21, and the transition electrode 26 is arranged on the same side of the liquid metal layer 21 on the front and back sides of the liquid metal layer 21.

[0048] The transition electrode 26 on the front and back sides of the liquid metal layer 21 is connected to the positive electrode or the negative electrode of the liquid metal layer 21 on the front and back sides, and the transition electrode 26 with the same polarity on the front and back sides of the liquid metal layer 21 is arranged at the corresponding same position on the front and back sides of the liquid metal layer 21.

[0049] The transition electrode 26 is a metal electrode, and the transition electrode 26 is arranged as a metal electrode to facilitate the conduction of electrical signals with the liquid metal layer 21.

[0050] The transition electrode 26 is preferably a Cu-PI electrode.

[0051] The interface 25 is connected to the transition electrode 26, and the interface 25 is directly and fixedly connected to the two layers of liquid metal layers 21 arranged symmetrically on the front and back sides, and the interface 25 is used to transmit the data of the stress sensor 20, and the interface 25 is preferably a PI-Cu interface 25, and the connection position of the interface 25 and the transition electrode 26 is located in the sensor sensitive layer substrate 22, so as to further ensure the stability of the circuit connection interface 25.

[0052] The PI-Cu and Cu-PI in the PI-Cu interface and the Cu-PI electrode have the same meaning, and the Cu-PI or PI-Cu means that it is made of copper-polyimide material, and the interface and the electrode made of copper-polyimide have good bending resistance and conductivity, and are suitable for flexible sensors.

[0053] The sensor sensitive layer substrate 22 located at the outermost side is made of nanofiber film, and the sensor sensitive layer substrate 22 located at the outermost side of the stress sensor 20 is preliminarily packaged through the self-packaging characteristics of the nanofiber film, so as to realize the preliminary packaging of the stress sensor 20.

[0054] Because the preliminary packaging of the stress sensor 20 is not firm and cannot guarantee the safety of the internal structure, a biodegradable plastic substrate layer 27 needs to be coated on the front and back of the sensor sensitive layer again. In actual production, the preliminary packaged stress sensor 20 can be directly fixed on the biodegradable plastic substrate layer 27, and another layer of biodegradable plastic substrate layer 27 is poured on the preliminary packaged stress sensor 20 provided with the biodegradable plastic substrate layer 27.

[0055] Thus, the stress sensor 20 is completely packaged, which can play a better protection role for the stress sensor 20.

[0056] And using the biodegradable plastic substrate layer 27, there is no accumulation and residue of toxic substances in the body tissue of the organism, which is safer and more practical.

[0057] The stress sensor 20 is fixed on the bone plate 10 after packaging, and the bone plate 10 and the stress sensor 20 form a whole, which is convenient to use.

[0058] The bone plate 10 is made of metal material, preferably a solid metal structure, and the bone plate 10 is a rectangular structure, preferably a steel plate structure.

[0059] The bone plate 10 is provided with a plurality of insertion holes 11 arranged in a straight line, and the plurality of insertion holes 11 are uniformly distributed and have equal distances between adjacent insertion holes 11. The insertion hole 11 is used to install a connecting component when the bone plate 10 is used, and the insertion hole 11 is preferably a screw insertion hole 11. When the bone plate 10 is used, a medical screw specially used in orthopedics is selected to pass through the screw insertion hole 11, and the medical screw is used to fix the bone plate 10 to achieve the function of fixing the broken bone.

[0060] The bone plate 10 is provided with a mounting groove 12 for mounting the stress sensor 20, and the structure of the mounting groove 12 is a rectangular frame structure. The local position of the bone plate 10 in the middle is used to set the insertion hole 11 and is not covered by the mounting groove 12. The mounting groove 12 is located on both sides of the insertion hole 11, and the mounting groove 12 is communicated at both ends, so that after the stress sensor 20 is installed in the mounting groove 12 of the bone plate 10, the stress sensor 20 will not protrude from the bone plate 10. It is preferred that the mounting groove 12 on the bone plate 10 is a flat surface after the stress sensor 20 is installed.

[0061] The shape of the mounting groove 12 corresponds to the shape of the stress sensor 20, and the stress sensor 20 is embedded in the mounting groove 12.

[0062] Two connected communication grooves 13 are formed at both ends of the mounting groove 12, one side of the communication groove 13 is smaller in size than the other side of the communication groove 13, the smaller size of the communication groove 13 is used for mounting the end joint of the sensor sensitive layer substrate 22, the liquid metal layer 21 and the conductive ink layer 23, while the larger size of the other side of the communication groove 13 is used for mounting the end joint of the other end of the sensor sensitive layer substrate 22, the liquid metal layer 21 and the conductive ink layer 23, and the larger size of the other side of the communication groove 13 is also used for accommodating the transition electrode 26 and the interface 25 connected with the transition electrode 26, and the larger size facilitates the installation of the transition electrode 26 and the interface 25.

[0063] The transition electrode 26 and the interface 25 are arranged in the communication groove 13 of the larger size at the end of the mounting groove 12, and the enameled wire 24 is welded at the interface 25 connected with the transition electrode 26, so as to strengthen the stability of the electrode of the interface 25.

[0064] The transition electrode 26 is arranged on the liquid metal layer, the transition electrode 26 is connected with the interface 25, and the enameled wire 24 is welded at the interface 25, so as to form stable signal transmission.

[0065] When the stress sensor 20 is installed on the bone plate 10, multiple processes are required to ensure that the stress sensor 20 can be stably installed on the bone plate 10 and normally realize the function of the stress sensor 20.

[0066] Before installation, the bone plate 10 is prepared, and all parts of the bone plate 10 need to be rounded to prevent the biological body from being greatly affected after being fixed in the biological body.

[0067] A layer of metal glue is uniformly brushed on the mounting groove 12 coated on the bone plate 10, at this time, the stress sensor 20 is embedded into the mounting groove 12 of the bone plate 10, and the stress sensor 20 is fixed with the bone plate 10 through the metal glue.

[0068] After the stress sensor 20 is fixed on the bone plate 10, the interface 25 of the stress sensor 20 is led out, the enameled wire 24 is welded at the interface 25 of the stress sensor 20, and the enameled wire 24 located on the bone plate 10 is fixed on the bone plate 10 by using strong glue, so as to further ensure the stability of the output electric signal of the interface 25 and the transition electrode 26.

[0069] The enameled wire 24 extends out of the bone plate 10, which is convenient for connecting with other components required by the bone plate, for example, a signal output end and a signal control end.

[0070] After the stress sensor 20 is fixed on the bone plate 10, the interface 25 part of the stress sensor 20 and the surface exposed part of the stress sensor 20 are covered with silica gel to separate the stress sensor 20 and the interface 25 part from the environment in the living body, so that the stress sensor 20 as a whole is more resistant to corrosion to adapt to the environment in the living body, and also does not affect the environment in the living body to avoid serious rejection reaction.

[0071] In other embodiments, when no hole is provided on the stress sensor 20 for mounting the mobile screw, a puncher is used to punch the stress sensor 20, so that the insertion hole 11 on the bone plate 10 does not interfere with the stress sensor 20 when the mobile screw is mounted, so as not to affect the normal use of the bone plate 10, and the excess silica gel and encapsulant are removed.

[0072] Through the above method, the bone plate 10 with the stress sensor 20 is obtained, and the specific structure is in turn from bottom to top: the bone plate 10, the metal glue, the biodegradable plastic substrate layer 27, the sensor sensitive layer substrate 22, the liquid metal layer 21, the conductive ink layer 23, the liquid metal layer 21, the sensor sensitive layer substrate 22, the biodegradable plastic substrate layer 27, and the silica gel.

[0073] After the stress sensor 20 is connected to the interface 25, the enameled wire 24 is connected, which is used to connect the electrical signal output end. The electrical signal output end is a wireless output end, and the device for realizing the electrical signal output is a wireless transmitter. The wireless transmitter transmits the signal to an external receiving device. The stress change detected by the stress sensor is output to the external receiving device through the wireless transmitter, which is convenient for personnel to directly observe the stress change.

[0074] The specific use principle is as follows: after the stress sensor 20 is installed on the bone plate 10, the bone plate 10 is fixed on the fractured bone to realize the connection of the fractured bone. After the bone fracture treatment operation is completed, the fractured bone restores the function of the bone of the living body. When the fractured bone is used after treatment, the fractured bone will deform in the normal use process because the fractured bone has not recovered to normal. The bone plate 10 for fixing the fractured bone will deform along with the fractured bone. At this time, the deformation of the bone plate 10 causes the corresponding deformation of the stress sensor 20 installed on the bone plate 10, so that the conductive ink layer 23 in the stress sensor 20 deforms. The conductive ink layer 23 changes the current flowing through the conductive ink layer 23 because the conductive ink layer 23 has the property that the resistance changes after deformation. When the current passes through the liquid metal layer 21 and is further transmitted to the electrical signal output end by the transition electrode 26, the electrical signal is transmitted to the receiving device outside the living body through the electrical signal output end, so as to facilitate the medical staff to observe the stress change of the fractured bone.

[0075] Example Two

[0076] An orthopedic bone plate 10 capable of installing a flexible stress sensor 20, comprising the bone plate 10, the bone plate 10 comprises the bone plate 10 of embodiment one, while the bone plate 10 needs to meet the following conditions:

[0077] The surface of the bone plate 10 is smooth, without defects such as edges, burrs, cracks, scratches, scars, etc.

[0078] The appearance is regular, and each ring and curved surface is uniformly transitioned.

[0079] The implantation hole 11 of the bone plate 10 has two parts, the shape of the implantation hole 11 corresponds to the shape of the screw, and the implantation hole 11 is composed of a head circular hole for accommodating the screw head and a penetrating hole for penetrating the screw part. When the screw passes through the implantation hole 11 for use, the screw head can be completely embedded into the head circular hole of the implantation hole 11, so that when the screw is used, the screw head will not protrude from the implantation hole 11, so that the screw will not affect the tissue in the organism.

[0080] In other embodiments, the implantation hole 11 can also be provided with threads, so as to realize the cooperation of the bone plate 10 and the bolt. The bone that needs to use the bone plate 10 is also provided with a threaded hole, and the bolt is used to fix the bone plate 10 and the bone by the threads provided in the implantation hole 11 of the bone plate 10 and the threaded hole of the bone that needs to use the bone plate 10.

[0081] When the bolt is used, the threads in the implantation hole 11 should be clear and complete, without missing and disorderly buckles.

[0082] The above-described embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it cannot be understood as limiting the scope of the patent of the present application. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A method for applying a flexible stress sensor to orthopedic bone plates, characterized in that, The application relates to a bone plate with a flexible stress sensor. The application provides a bone plate, a biodegradable plastic substrate, a sensor sensitive layer substrate; The biodegradable plastic substrate and the sensor sensitive layer substrate are symmetrically arranged in double layers; A liquid metal layer is printed between the double-layer sensor sensitive layer substrates, and the liquid metal layer is symmetrically arranged in double layers; a transition electrode is arranged on the double-layer liquid metal layer; A conductive ink layer is printed between the double-layer liquid metal layers; An interface is connected to the transition electrode; Thus, a primary encapsulated stress sensor is formed; The primary encapsulated stress sensor is installed between the double-layer biodegradable plastic substrates to form a completely encapsulated stress sensor; The surface of the bone plate is uniformly coated with metal glue, and the completely encapsulated stress sensor is attached to the surface of the bone plate; The outer end of the interface is connected to an enameled wire, and the wire is fixed to the end of the bone plate by using strong glue; The interface part and exposed part of the completely encapsulated stress sensor installed on the bone plate are encapsulated and solidified by using silica gel.

2. The method of applying a flexible stress sensor to an orthopedic bone plate of claim 1, wherein, The sensor sensitive layer substrate is made of electrostatic spinning.

3. The method of applying a flexible stress sensor to an orthopedic bone plate of claim 2, wherein, The electrostatic spinning is prepared into a nanofiber membrane as the sensor sensitive layer substrate.

4. The method of claim 1, wherein the flexible stress sensor is applied to the orthopedic bone plate by, The liquid metal layer is printed on the sensor sensitive layer substrate by cooperating with a template.

5. The method of applying a flexible stress sensor to an orthopedic bone plate of claim 1, wherein, The conductive ink layer is printed on the sensor sensitive layer substrate by cooperating with a template.

6. The method of applying a flexible stress sensor to an orthopedic bone plate of claim 1, wherein, The interface is a PI-Cu interface, and the transition electrode is a Cu-PI electrode.

7. The method of applying a flexible stress sensor to an orthopedic bone plate of claim 1, wherein, The completely encapsulated stress sensor is also perforated, so that the holes on the sensor correspond to the holes on the bone plate.

8. An orthopedic bone plate with flexible stress sensors, characterized in that The application relates to a bone plate with a completely encapsulated stress sensor. The completely encapsulated stress sensor is a multilayer composite structure, and the multilayer composite structure of the completely encapsulated stress sensor is biodegradable plastic substrate, sensor sensitive layer substrate, liquid metal layer, conductive ink layer, liquid metal layer, sensor sensitive layer substrate, biodegradable plastic substrate in sequence, and a transition electrode is arranged on the double-layer symmetric liquid metal layer.

9. The orthopedic bone plate with flexible stress sensors of claim 8, wherein, The bone plate is made of a solid metal material in a rectangular strip structure, a plurality of evenly distributed insertion holes are arranged on the bone plate, a mounting groove is arranged around the outer side of the bone plate, the completely encapsulated stress sensor is mounted in the mounting groove, the mounting groove is partially in a frame structure, and the two ends of the mounting groove are communicated grooves, and one side of the communicated grooves is used for mounting the interface.

10. The bone plate with a flexible stress sensor according to claim 9, wherein The completely encapsulated stress sensor is mounted on the bone plate, and the structure is sequentially arranged from bottom to top as the bone plate, metal glue, the completely encapsulated stress sensor, and silica gel; the transition electrode is connected to the interface; and the interface is mounted in the side with a larger distance in the middle of the communicated grooves at the two ends.

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