Detailed Description
The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application.
It should be noted that like reference numerals and letters refer to like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures. Meanwhile, in the description of the present application, the terms "first", "second", and the like are used only to distinguish the description, and are not to be construed as indicating or implying relative importance.
In the description of the present application, it should be noted that, directions or positional relationships indicated by terms such as "upper", "lower", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or directions or positional relationships in which the inventive product is conventionally put in use, are merely for convenience of describing the present application and simplifying the description, and are not indicative or implying that the apparatus or element to be referred to must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limitations of the present application.
In the description of the present application, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected through an intermediary, or in communication between two elements. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art.
The intramedullary nail belongs to a medical instrument internal fixation instrument, and can be divided into humerus, femur, tibia and hip intramedullary nails according to the position. After the intramedullary nail is inserted into the intramedullary cavity, the specific location of the distal locking hole is obscured by surrounding tissue and bone, making it difficult to accurately drill and drive the locking nail.
Currently, a series of still images are obtained clinically, mainly by means of X-ray imaging, identifying the relative position of the locking holes of the intramedullary nail, with the drawback that the surgeon and the operating personnel are exposed to the radiation for a long time, creating additional risks. Therefore, some methods have been proposed to solve the positioning problem, one of them is a mechanical positioning method, which can be aimed at very accurately in vitro, but during the insertion process of the intramedullary nail, the intramedullary nail may be deformed due to the extrusion of the tissue of the human body, the position of the locking hole may be shifted, and then the screw cannot be placed into the locking hole very accurately by mechanical positioning.
Various electromagnetic localization techniques have also been explored, for example, one electromagnetic method that has been proposed is static magnetic field targeting, which involves detecting the position of a permanent magnet inserted into an intramedullary nail. Active electromagnetic systems use electromagnetic transmitters and receivers, at least one of which is located or inserted within a nail to aid in identification.
Based on the above-mentioned shortcomings, it is considered to introduce an electromagnetic-based method. However, electromagnetic methods have the difficulty that they must be sensitive enough to detect the location of small holes in metal parts. In this way, they are sensitive, whether due to the surgical device itself, due to eddy currents generated in the conductive non-ferromagnetic material, or due to electromagnetic field distortions caused by the presence of conductors or electromagnetic fields nearby. The exact nature of the distortion varies from procedure to procedure, depending on the length of the nail, the material, and the relative position of the surgical device. For example, practical investigation of static magnetic field sighting methods has found that the sighting accuracy of the system is inadequate, and because of the similar magnitudes of magnetic fields from other sources and nearby ferromagnetic materials, there are large offset values, which are detrimental to sighting, making it unreliable to use the method.
In view of the above-mentioned shortcomings, an active system is provided in which an intramedullary nail includes a central shaft into which a sensor is inserted at a known distance. The two transmitters are located on support arms that are secured to an alignment jig that surrounds the drill sleeve. The microcontroller processes the signals and the display module displays the positions of the nails and holes and the current drilling position. The boring grab may then be adjusted until the current boring location is aligned with the target bore.
Referring to the drawings, an intramedullary nail positioning system for realizing intramedullary nail positioning will be described first, as shown in fig. 1, and fig. 1 is a schematic structural diagram of an intramedullary nail positioning system according to an embodiment of the present application. As shown in FIG. 1, the intramedullary nail positioning system includes a distal aiming block 110, first and second transmitters 120 and 130 mounted at both ends of the distal aiming block 110, a drill guide 140, and a sensor 150 (shown in FIG. 2).
The distal aiming block 110 is mounted on the drill guide 140, and the first and second transmitters 120 and 130 are located on both sides of the drill guide 140.
Illustratively, the distal sight 110 is provided with a through-hole through which the drill guide 140 passes to enable the distal sight 110 to be mounted on the drill guide 140.
Optionally, the first transmitter 120 forms a first distance with the mounting location of the distal rest 110 and the drill guide 140, the second transmitter 130 forms a second distance with the mounting location of the distal rest 110 and the drill guide 140, and the first distance is equal to the second distance. Illustratively, the first and second transmitters 120 and 130 are symmetrically disposed on both sides of the drill guide 140 with the drill guide 140 as an axis of symmetry.
Alternatively, the first emitter 120 may be an electron emitting coil, and the second emitter 130 may also be an electron emitting coil.
The sensor 150 is mounted within the target intramedullary nail for receiving and processing the transmitted signals of the first transmitter 120 and the second transmitter 130.
As shown in fig. 2, the intramedullary nail may include an intramedullary nail handle 210 and an intramedullary nail shaft 220. The sensor 150 may be mounted within the intramedullary nail shaft 220. Alternatively, the sensor 150 may be mounted at a designated location on the intramedullary nail shaft 220. For example, the sensor 150 is located a fixed distance from the edge of the intramedullary nail shaft 220. The fixed value may be set at the length of the actual intramedullary nail, for example, at one third, two thirds, etc. of the edge of the intramedullary nail shaft 220.
The sensor 150 includes a signal acquisition module, a signal extraction module, and a signal calculation module.
The intramedullary nail can be positioned by three modules, namely a signal acquisition module, a signal extraction module and a signal calculation module of the sensor 150.
The signal acquisition module may be implemented by a magnetic field sensing element magneto-resistive element, a coil, or other sensing element. For example, a coil may be used to collect signals transmitted by the transmitter.
Alternatively, the emitter may be an electron emitting coil. Considering that the magnitude of the magnetic field is inversely proportional to the square of the distance in space, since the sensor 150 is at a certain distance from the transmitter, the signal of the magnetic field signal transmitted by the transmitter reaching the sensor 150 is relatively weak, and in order to make the acquired signal more accurate, the operation amplification processing can be performed on the weak magnetic field signal during the signal extraction.
Further, signal noise is formed due to the fact that a circuit power supply interference signal, an interference signal mixed by environmental radiation and the like may be coupled in a weak signal. Based on this, the magnetic field signal can be subjected to a filter process at the time of signal extraction.
In this embodiment, the signal extraction module may include an operational amplifier unit and a filtering unit, where the operational amplifier unit performs an operational amplifier process on the magnetic field signal, and the filtering unit may perform a filtering process on the magnetic field signal to remove noise.
Considering that the emitter can be an embodiment of an electron emitting coil, the magnetic field is directional, the collected voltage signal is positive and negative, and only the detection value conforming to the direction of the magnetic field of the emitter is true, otherwise, the voltage value of the collected interference signal is the voltage value of the collected interference signal. Therefore, the signal extraction module may include a positive and negative judgment unit to perform positive and negative judgment on the magnetic field signal emitted by the emitter, so as to extract a correct magnetic field signal.
In order to further improve the accuracy of the extracted signal, the signal extraction module may further include a signal processing unit that may digitally filter the received signal to remove discrete data, so as to improve the accuracy of the extracted signal. Alternatively, the signal processing module may be a software unit, to implement digital filtering processing by processing digital signals.
In this embodiment, the voltage values obtained by calculation may be mapped to the corresponding position values one by one based on fitting the calculation results of the signals extracted at different times.
As shown in fig. 3, a schematic circuit configuration of the sensor 150 is shown. In the figure, R and L are respectively the internal resistance and inductance of the coil, C is the distributed capacitance of the coil, rt is the matching resistance, R1 and R2 are gain resistors, and C1 is the filter capacitance. The induction signal of the coil is Ui, the voltage reaching the input end of the operational amplifier G after passing through the r, L and C networks is Uo, the output of the operational amplifier G is Ua finally, and the input impedance of the operational amplifier is usually large, so that the influence of the operational amplifier G on the matching resistance can be ignored. The op-amp of appropriate parameters is selected to ensure adequate gain stability in the active band.
In this embodiment, the internal resistance r, the inductance L, the distributed capacitance C, and the operational amplifier G shown in fig. 3 may form an operational amplifier unit and a filter unit of the signal extraction module.
Illustratively, as shown in fig. 3, the sensor 150 intrinsic noise includes an internal resistance thermal noise eR of the coil, a thermal noise iRt of a matching resistance of the coil, a voltage noise en and a current noise in of the operational amplifier G, and gain resistance thermal noises eR1 and eR2 of the operational amplifier G. The current noise of the operational amplifier G is further divided into seven types of noise, wherein one part is voltage noise generated by the current noise flowing through the coil network, and the other part is voltage noise generated by the current noise flowing into the gain resistors R1 and R2.
Considering that the noise of the coil is related to the frequency, the voltage noise of the operational amplifier G and the thermal noise of the matching resistor are dominant in the effective frequency band of the sensor 150, and the voltage noise of the operational amplifier G can be reduced by selecting a low noise device, but the thermal noise of the matching resistor cannot be reduced after determining the operating state of the coil. Therefore, the embodiment of the application can reduce voltage noise by selecting a low-noise device.
Optionally, the intramedullary nail positioning system may further comprise a stop for stopping the sensor 150 mounted in the target intramedullary nail.
Optionally, as shown in fig. 4, the intramedullary nail positioning system may further comprise a control device 160. The control device 160 may include a memory and a processor. The memory and the processor are electrically connected with each other directly or indirectly to realize data transmission or interaction. For example, the components may be electrically connected to each other via one or more communication buses or signal lines. The processor is configured to execute the executable modules stored in the memory.
The Memory may be, but is not limited to, random access Memory (Random Access Memory, RAM), read Only Memory (ROM), programmable Read Only Memory (Programmable Read-Only Memory, PROM), erasable Read Only Memory (Erasable Programmable Read-Only Memory, EPROM), electrically erasable Read Only Memory (Electric Erasable Programmable Read-Only Memory, EEPROM), etc. The memory is configured to store a program, and the processor executes the program after receiving an execution instruction, and a method executed by the control device 160 for defining a procedure according to any of the embodiments of the present application may be applied to or implemented by the processor.
The processor may be an integrated circuit chip having signal processing capabilities. The processor may be a general-purpose processor, including a central processing unit (Central Processing Unit, CPU), a network processor (Network Processor, NP), a digital signal processor (DIGITAL SIGNAL processor, DSP), an Application Specific Integrated Circuit (ASIC), a field programmable gate array (Field Programmable GATE ARRAY, FPGA), a programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component. The disclosed methods, steps, and logic blocks in the embodiments of the present application may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.
As shown in fig. 4, the control device 160 may include a display 161, which display 161 may be used to display data during use of the intramedullary nail. The display 161 provides an interactive interface (e.g., a user interface) between the control device 160 and the user or is used to display image data to a user reference.
Alternatively, the control device 160 may include a button 162, which button 162 may be used to control parameters required in the positioning process. Alternatively, the button 162 may be a physical key as shown in fig. 4, or a touch button displayed on the display 161.
The display 161 may be, for example, a display screen including light-emitting diodes (LEDs). The display screen can dynamically display the aiming state of the drilling center of the intramedullary nail positioning system and the far-end hole of the intramedullary nail.
Illustratively, there is theoretically a target location for positioning, and there is a deviation from the target location based on the actual test values obtained by the intramedullary nail positioning system, which may be described as a positioning aiming deviation, and when the positioning aiming deviation is zero, the intramedullary nail positioning is completed. The target location may be represented on the display screen with a first identification. The actual test value may be represented by a second identifier. The distance of the first marker from the second marker may represent a positioning aiming deviation. When the positioning aiming deviation is zero, the first mark and the second mark are overlapped on the display screen, and the positioning can be indicated to be completed.
The control device 160 may also include an interface 163, which interface 163 may be used for charging. The interface 163 may be a Type-c interface 163, a USB interface 163, or the like.
The first transmitter 120, the second transmitter 130 and the sensor 150 are all connected to the control device 160, and the control device 160 is configured to send control instructions to the first transmitter 120, the second transmitter 130 and the sensor 150.
The principle of operation of the intramedullary nail positioning system provided by embodiments of the present application is to transmit signals via two transmitters mounted to the distal aiming block 110. The sensor 150 within the intramedullary nail may detect this signal. The two transmitters are symmetrically positioned on either side of the drill guide 140 such that when the sensor 150 receives an equal signal, the drill guide 140 will face the center of the intramedullary nail. The image may then be displayed by a display 161 on the control device 160, which may simulate the target position of the drill guide 140.
In use, the first emitter 120, the second emitter 130, and the sensor 150 may be subjected to a sterilization process. The first emitter 120, the second emitter 130, and the sensor 150 may optionally be sterilized using high temperature and high pressure.
The calibration action of the positioning system in this embodiment includes inserting a sterile intramedullary nail into the jig, inserting the sensor 150 into the central axis of the intramedullary nail, securing the support arm to the jig, and then adjusting the jig until the drill sleeve in the support arm is aligned with the target hole on the nail, whereby the positioning system completes the calibration. The system is disassembled as needed for surgery, nails are inserted into the patient's bone, and then the sensors 150 are inserted. The jig is then reassembled onto the patient using the support arm and the calibrated system is used to align the drill sleeve with the target hole using the display module.
The control device 160 comprises a battery. Illustratively, the battery may be a 2000 milliamp battery that may be recharged repeatedly by a Type interface 163 charger connected to a 110-240vAC power outlet. Alternatively, the battery may be operated for 3 to 4 hours after full charge.
To protect the safety of the battery, the battery is automatically turned off after being fully charged for a first specified period of time, which may be 30 minutes, for example.
For example, the control device 160 may include a display unit on which a battery signal may be displayed, an indication bar of which may display the charge amount when the battery is in a full state. In normal use, the device need only be turned on for a few minutes at the initial setting and then remain for a second designated period of time, which may be 5-10 minutes, during the positioning and drilling process.
Under the above voltage conditions, the charge indicator light will change from a red light to a green light when the battery is fully charged.
In this embodiment, the first emitter 120, the second emitter 130, and the sensor 150 are connected to the control device 160 by wires. In one example, the color coding of the wires corresponds to the sensor 150 for yellow and the first emitter 120 and the second emitter 130 for blue.
Prior to use of the intramedullary nail positioning system provided by embodiments of the present application, a target intramedullary nail may be coupled to the intramedullary nail handle 210 for ease of operation.
Optionally, the intramedullary nail positioning system may further include an adapter bracket and an angle adjustment bracket (not shown), among other components.
Illustratively, the adaptor is mounted on the intramedullary nail handle 210 described above. The angle adjusting frame is mounted on the adapter frame.
The distal aiming block 110 may be mounted to the adapter block.
Alternatively, the drill guide 140 may include a drill sleeve assembly, a drill bit, or the like. The drill sleeve assembly may pass through a central bore of the distal aiming block 110. In use, the forward end of the drill sleeve assembly may bear against the outer surface of the intramedullary nail.
The drill bit can be inserted into the drill bit sleeve assembly bore and the angle adjustment bracket knob is rotated such that the drill bit sleeve assembly bore is centered on the same axis as the distal threaded bore of the target intramedullary nail. And a drill bit is inserted into the intramedullary nail threaded hole.
By arranging a plurality of processing modules on the sensor 150, the intramedullary nail positioning system provided by the embodiment of the application can enable received signals to be more reliable.
The embodiment of the application also provides an intramedullary nail positioning method, which can be applied to the intramedullary nail positioning system, and specifically, the steps in the method can be executed by a sensor in the intramedullary nail positioning system. As shown in fig. 5, the method may include the following steps.
Step 310 receives a first transmit signal transmitted by a first transmitter disposed at a first designated location.
The first transmit signal may be received, for example, by a sensor 150 in the intramedullary nail positioning system. The sensor 150 may have an electron emission coil disposed therein, through which the first emission signal is received.
Step 320 receives a second transmission signal transmitted by a second transmitter disposed at a second designated location.
Wherein the first designated location and the second designated location are locations on the distal aiming block 110 of the intramedullary nail positioning system. Reference may be made to the description of the previous intramedullary nail positioning system embodiments regarding the mounting positions of the first and second transmitters 120, 130, which are not repeated here.
The second transmitted signal may be received, for example, by a sensor 150 in the intramedullary nail positioning system. The sensor 150 may have an electron emission coil disposed therein, through which the second emission signal is received.
Step 330, performing screening processing on the first transmission signal and the second transmission signal to obtain a first processing signal and a second processing signal.
Alternatively, noise in the first and second transmit signals may be removed by a screening process, so that the first and second processed signals may better express the relative positions of the first and second transmitters.
Step 340, calculating the first processed signal and the second processed signal to obtain a target trajectory of the drill guide.
In this embodiment, the relative positions of the first emitter and the second emitter and the sensor can be determined by the first processing signal and the second processing signal, so as to realize positioning of the sensor and the position of the sensor.
In this embodiment, the relative position of the drill guide and the intramedullary nail is fixed relative to each other when the intramedullary nail positioning system is in use, and the sensor is mounted in a fixed position within the intramedullary nail shaft of the intramedullary nail, so that the real-time position of the drill guide can be determined after the relative positions of the first emitter and the second emitter and the sensor are determined.
For example, a real-time position of the drill guide may be determined based on the first processed signal and the second processed signal, and a target trajectory of the drill guide may be traced based on the real-time position.
Optionally, step 330 may include steps 331 to 333.
And 331, performing operational amplification processing on the first transmission signal and the second transmission signal to obtain a first operational amplification signal and a second operational amplification signal.
The step 331 may include performing an operational amplification process on the first transmission signal to obtain a first initial operational amplification signal, performing a filtering process on the first operational amplification signal to obtain a first operational amplification signal, performing an operational amplification process on the second transmission signal to obtain a second initial operational amplification signal, and performing a filtering process on the second operational amplification signal to obtain a second operational amplification signal.
And step 332, performing positive and negative screening on the first operational amplifier signal and the second operational amplifier signal to obtain a first screening signal and a second screening signal.
Optionally, the first transmitter 120 and the second transmitter 130 are magnetic field transmitters.
Step 332 may include performing positive and negative filtering on the first op-amp signal according to the magnetic field direction of the first transmitter 120 to filter out a first filtered signal corresponding to the magnetic field direction of the first transmitter 120, and performing positive and negative filtering on the second op-amp signal according to the magnetic field direction of the second transmitter 130 to filter out a second filtered signal corresponding to the magnetic field direction of the second transmitter 130.
Step 333, performing data filtering on the first screening signal and the second screening signal to obtain a first processing signal and a second processing signal.
The step 333 may include performing a digital filtering process on the first screening signal to remove discrete data in the first screening signal to obtain a first processed signal, and performing a digital filtering process on the second screening signal to remove discrete data in the second screening signal to obtain a second processed signal.
In this embodiment, the intramedullary nail positioning method may further include forming a trajectory graph based on the parameters of the target intramedullary nail and the target trajectory for display at the control device 160 of the target intramedullary nail.
For example, a track map may be displayed on an LED display screen of the control device 160. For example, the positional targeting deviation and the real-time status data of the target intramedullary nail may be dynamically displayed in an LED display screen.
The trace map may be, for example, a trace formed from real-time status data. The theoretical target position may be displayed on the display screen by a first indicator and the real-time status data may be displayed on the display screen by a second indicator. The distance between the first and second markers may be used as a positioning aiming offset.
Taking the first mark as a circle, the second mark as a dot as an example, moving the dot of the second mark to the circle of the first mark along with the positioning, and indicating that the positioning is completed when the circle coincides with the dot.
Further, the first and second markers may be displayed in a different color than in the positioning process upon completion of positioning. For example, the first and second markers may be displayed in red during positioning, and may be displayed in green upon completion of positioning and after completion of positioning.
Alternatively, the parameters of the target intramedullary nail may include parameters such as the length of the intramedullary nail, the thickness of the intramedullary nail, information about the location of the locking holes of the intramedullary nail, the location of the sensor within the stem of the intramedullary nail, etc.
Alternatively, the parameters of the target intramedullary nail may be intramedullary nail types, each of which corresponds to a uniquely determined intramedullary nail size.
The trajectory graph may include, for example, the relative positions of the drill bit and the locking hole of the target intramedullary nail.
By displaying the track diagram, the positioning needle can be conveniently and accurately driven into the locking hole by a related technician.
By the method, the received signals can better represent the position information of the first emitter 120 and the second emitter 130 through multi-type processing, so that the positioning of the intramedullary nail can be better realized, the positioning of the intramedullary nail can be more accurate, an effective data basis can be provided for drilling the intramedullary nail and driving the locking nail, and the accuracy of drilling and driving the locking nail is improved.
The above description is only of alternative embodiments of the present application and is not intended to limit the present application, and various modifications and variations will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application. It should be noted that like reference numerals and letters refer to like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the application is subject to the protection scope of the claims.