Pedicle screw implantation equipment based on bioelectrical impedance guidance

Abstract

The invention provides pedicle screw implanting equipment based on bioelectrical impedance guidance. The pedicle screw implanting equipment comprises a handle, a sleeve, a connecting rod and a probe, the sleeves are detachably connected with one another; a probe is also arranged in the handle and the sleeve; the lower end of the probe is also sleeved with a connecting rod; the connecting rod is detachably connected with a vertebral pedicle screw; the lower end of the probe extends out of the lower end of the pedicle screw; an electrical impedance acquisition system is arranged in the handle, and the electrical impedance acquisition system is electrically connected with the probe. Implantation of the pedicle screw can be achieved, the bioelectrical impedance value of the tip tissue of the screw can be collected in the implanting process, impedance information of the tip of the screw is collected in real time to sense the tissue layer and the position where the screw is located currently, important tissue and nerve structures are prevented from being damaged, and the accuracy and safety of screw implantation are guaranteed; according to the invention, the tissue information of the tip can be converted into the electrical impedance value, and the type of the tip tissue is output according to the electrical impedance value.

Description

Technical Field

[0001] The present invention relates to the technical field of pedicle screw implantation equipment, in particular to a pedicle screw implantation equipment based on bioelectrical impedance guidance. Background Art

[0002] Pedicle screw implantation is a common and critical spinal surgical procedure. It is currently the most widely used and successful technology for treating spinal pathological changes caused by trauma, tumors, scoliosis or degenerative diseases, and requires extremely high precision and safety.

[0003] However, while traditional surgical navigation technology that relies on X-ray fluoroscopy can help improve surgical accuracy and assist doctors in observing the position and direction of screws, during surgery, repeated fluoroscopy is required due to the inability to provide timely feedback on the current screw implantation status. This carries with it the risk of radiation exposure, posing a threat to the health of both doctors and patients. Furthermore, the technology is susceptible to the patient's position and other external environmental factors, potentially causing the screw to pierce the pedicle wall and become misplaced, leading to a series of complications. Furthermore, due to the lack of real-time intraoperative observation and monitoring, the surgeon cannot directly observe the penetration depth of the screw tip within the cancellous bone channel or its anatomical relationship with surrounding nerves and blood vessels, resulting in blind operation. Summary of the Invention

[0004] In response to the shortcomings of the existing technology, the present invention provides a pedicle screw implantation device based on bioelectrical impedance guidance. The present invention can sense the tissue layer and position of the screw in real time, prevent puncture of blood vessels, damage to tissue and nerve structures, and ensure the accuracy and safety of screw implantation.

[0005] The technical solution of the present invention is: a pedicle screw implantation device based on bioelectrical impedance guidance, including a handle, a sleeve, a connecting rod, and a probe; the sleeve is detachably connected to the sleeve; the handle and the sleeve are also provided with a probe; the lower end of the probe is also sleeved with a connecting rod; the connecting rod is detachably connected to the pedicle screw; and the lower end of the probe extends from the lower end of the pedicle screw; the handle is provided with an electrical impedance acquisition system, and the electrical impedance acquisition system is electrically connected to the probe.

[0006] Preferably, the cross-section of the handle is a T-shaped structure, including a grip portion and a connecting portion; the grip portion has a chamber for installing the electrical impedance acquisition system; the lower end of the connecting portion is provided with a threaded portion, and the connecting portion is connected to the threaded portion of the sleeve through its threaded portion.

[0007] Preferably, the sleeve is further provided with a fixing screw, which can pass through the sleeve and abut against the probe arm inside the sleeve.

[0008] Preferably, the lower end of the connecting rod is further provided with a corresponding threaded portion, and the pedicle screw is connected to the threaded portion of the connecting rod through its threaded portion.

[0009] Preferably, the electrical impedance acquisition system includes a main control unit, and a power supply circuit, an impedance acquisition circuit, a buzzer and an LED light group connected to the main control unit; the impedance acquisition circuit collects the electrical impedance value of the tissue to be tested through a probe, and returns the collected impedance information to the main control unit. The main control unit classifies the data and feeds back the identification results to the user in the form of sound and light through the LED light group and the buzzer.

[0010] Preferably, the main control unit adopts a main control chip of model STM32F411CEU6.

[0011] Preferably, the power supply circuit includes a 4.2V lithium battery, a boost circuit, a digital power supply and an analog power management circuit; the 4.2V lithium battery ensures long-term safe operation of the battery through a lithium battery protection chip model XB4908, and the system can be powered by turning on the toggle switch SS-12D01-G6; the 4.2V lithium battery is connected to the digital power supply and the analog power management circuit through a boost circuit, and the impedance acquisition circuit is powered after the voltage is boosted to 5V by the boost circuit.

[0012] The beneficial effects of the present invention are:

[0013] 1. The present invention can realize the implantation of pedicle screws, and can collect the bioelectrical impedance value of the screw tip tissue during the implantation process. The impedance information of the screw tip is collected in real time to sense the tissue layer and position of the current screw to avoid damaging important tissues and neural structures;

[0014] 2. The present invention can convert the tissue information of the tip into an electrical impedance value and output the type of the tip tissue according to the electrical impedance value;

[0015] 3. The pedicle screw of the present invention is connected to the device through a thread, so it is easy to disassemble and assemble;

[0016] 4. The present invention fixes the electrical impedance sensing probe to the tip of the pedicle screw through structural coordination, thereby realizing sensor integration at the tip of the pedicle screw and rapid disassembly, assembly, and replacement of the screw probe.

[0017] 5. The present invention designs an integrated, small, portable bioelectrical impedance sensing device, which realizes relatively accurate electrical impedance acquisition through the analog front-end chip AD5933 combined with the main control chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the device of the present invention;

[0019] Figure 2 It is a partially enlarged structural diagram of the device of the present invention;

[0020] Figure 3 Schematic diagram of the structure of the electrical impedance acquisition system of the present invention;

[0021] Figure 4 This is a structural framework diagram of the electrical impedance acquisition system of the present invention;

[0022] Figure 5 This is a circuit diagram of the main control unit of the present invention;

[0023] Figure 6 A circuit diagram of the lithium battery of the present invention;

[0024] Figure 7 is a circuit diagram of a boost circuit of the present invention;

[0025] Figure 8 A circuit diagram of a digital power supply and an analog power management circuit of the present invention;

[0026] Figure 9 A circuit diagram of an impedance acquisition circuit according to the present invention;

[0027] Figure 10 This is a circuit diagram of the buzzer and LED light assembly of the present invention.

[0028] In the figure, 1-handle; 2-sleeve; 3-connecting rod; 4-probe; 5-main control unit; 6-lithium battery; 7-buzzer; 8-LED light; 9-pedicle screw;

[0029] 11-hand grip; 12-connecting part;

[0030] 21-Fixing screw. DETAILED DESCRIPTION

[0031] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings:

[0032] This embodiment provides a pedicle screw implantation device based on bioelectrical impedance guidance, comprising a handle 1, a sleeve 2, a connecting rod 3, and a probe 4; the sleeve 2 is detachably connected to the sleeve 2; the handle 1 and the sleeve 2 are further provided with a probe 4; the lower end of the probe 4 is further provided with a connecting rod 3; the upper end of the connecting rod 3 is detachably connected to a pedicle screw 9; Figure 2 As shown, the lower end of the probe 4 extends from the lower end of the pedicle screw 9 to contact the tissue to be measured; an electrical impedance acquisition system is provided in the handle 1, and the electrical impedance acquisition system is electrically connected to the probe 4.

[0033] As preferred in this embodiment, Figure 1As shown, the cross-section of the handle 1 is a T-shaped structure, including a grip portion 11 and a connecting portion 12; in this embodiment, the grip portion 11 is a circular structure, and the grip portion 11 has a chamber for installing an electrical impedance acquisition system; a threaded portion is provided at the lower end of the connecting portion 12, and the connecting portion 12 is connected to the threaded portion of the sleeve 2 through its threaded portion.

[0034] As preferred in this embodiment, Figure 1 As shown, the sleeve 2 is further provided with a fixing screw 21 , which can pass through the sleeve 2 and abut against the probe 4 arm inside the sleeve 2 .

[0035] As preferred in this embodiment, Figure 1 As shown, the lower end of the connecting rod 3 is also provided with a corresponding threaded portion, and the pedicle screw 9 is connected to the threaded portion of the connecting rod 3 through its threaded portion.

[0036] As preferred in this embodiment, Figure 3 、 4 As shown, the electrical impedance acquisition system is disposed within the hand grip 11 and includes a main control unit 5, a power supply circuit connected to the main control unit 5, an impedance acquisition circuit, a buzzer 7, and an LED light assembly 8. The impedance acquisition circuit is connected to the probe 4. The impedance acquisition circuit emits an excitation signal of a corresponding frequency, which is output through the probe 4 to the tissue to be measured. The excitation signal is then collected back into the impedance acquisition circuit via the probe 4. The impedance acquisition circuit amplifies, low-pass filters, performs analog-to-digital conversion, and performs a discrete Fourier transform (DFT) on the collected signal to obtain information such as the amplitude and phase angle of the electrical impedance. The collected impedance information is then returned to the main control unit 5. Due to the different electrical conductivities of cortical bone, cancellous bone, and blood in the pedicle screw implantation scenario, the electrical impedance information will vary significantly. The amplitude and phase angle in the electrical impedance information are used as characteristic information for classification to achieve tissue classification. The identification results are then fed back to the user via the LED light assembly 8 and buzzer 7 in the form of flashing lights of different colors and sounds of different tones.

[0037] In this embodiment, the calculation formula of the electrical impedance value Z is as follows:

[0038]

[0039] Where R0 represents the resistance at zero frequency; R ∞ represents the resistance at infinite frequency; s is the angular frequency; C ∞ is a constant related to the behavior of biological tissue; α represents the degree of dispersion of the polarization process of biological tissue.

[0040] The above equation effectively describes the ion concentration of the intracellular and extracellular fluids and their response to electrical current. This is accomplished by applying a low-intensity AC voltage to a biological tissue sample and measuring the corresponding current. Because biological tissue is composed of components with varying electrical conductivities and permittivities (e.g., cell membranes, cytoplasm, and extracellular matrix), the electrical impedance of the tissue exhibits distinct changes at different frequencies.

[0041] In this embodiment, the information collected by the electrical impedance acquisition system primarily includes the applied excitation frequency, as well as the impedance amplitude (|Z|) and phase angle (θ) at the corresponding frequency. The changing trends of the amplitude and phase angle at different frequencies can reflect the electrical properties of the tissue and extract parameters from the frequency response. Frequency domain features such as phase difference and amplitude change are obtained to distinguish different tissues. Equation (1) is used to fit the impedance data, thereby extracting parameters such as capacitance and resistance.

[0042] As preferred in this embodiment, Figure 5 As shown, the main control unit 5 adopts a main control chip of model STM32F411CEU6.

[0043] As a preferred embodiment of this invention, the power supply circuit includes a 4.2V lithium battery 6, a boost circuit, a digital power supply and an analog power management circuit; the 4.2V lithium battery 6 is ensured to work safely for a long time through a lithium battery protection chip with model number XB4908, and the system can be powered by turning on the toggle switch SS-12D01-G6; the 4.2V lithium battery 6 is connected to the digital power supply and the analog power management circuit through a boost circuit, and the impedance acquisition circuit is powered after being boosted by the boost circuit.

[0044] As preferred in this embodiment, Figure 6 As shown, the first and second pins of the lithium battery protection chip XB4908 are respectively connected to the positive electrode VBAT+ and the negative electrode VBAT- of the 4.2V lithium battery 6; the positive electrode VBAT+ of the 4.2V lithium battery 6 is connected to the toggle switch SS-12D01-G6; the positive electrode VBAT+ and the negative electrode VBAT- of the 4.2V lithium battery 6 are also connected to the battery holder BX-PH2.0-2PZZ.

[0045] As preferred in this embodiment, Figure 7As shown, the boost circuit includes a boost chip ETA1061, the 6th pin of the boost chip ETA1061 is connected to the 3rd pin of the toggle switch SS-12D01-G6; the 1st pin of the boost chip ETA1061 outputs a 5V voltage; and the 3rd pin of the boost chip ETA1061 is connected to the 14th pin of the main control chip STM32F411CEU6; resistors R29, R28, and capacitors C20, C19 are also connected between the 1st, 2nd, and 5th pins of the boost chip ETA1061; the 6th and 4th pins of the boost chip ETA1061 are also grounded GND.

[0046] As preferred in this embodiment, Figure 8 As shown, the digital power supply and analog power management circuit includes two magnetic bead chip inductors GZ1608U600TF; since the impedance acquisition circuit has high power supply requirements, the magnetic bead chip inductor has a strong impedance effect on high-frequency noise, which can effectively filter out high-frequency interference on the power line, block the propagation of these high-frequency signals, and prevent these noises from entering the chip and affecting its normal operation. The magnetic bead inductor is attached to its power input end, which can suppress high-frequency noise, improve power purity, reduce interference, and ensure the accuracy of chip measurement and the stability of the system. The two ends of the first magnetic bead chip inductor GZ1608U600TF are connected to GND and AGND respectively; one end of the second magnetic bead chip inductor GZ1608U600TF is connected to the first pin of the boost chip ETA1061, and the other end outputs a +5V analog voltage. The analog power supply and the digital power supply part are isolated by the magnetic bead chip inductor to ensure the stability and reliability of the system impedance acquisition.

[0047] As preferred in this embodiment, Figure 9 As shown, the impedance acquisition circuit includes an impedance acquisition chip AD5933YRSZ. The 6th pin of the impedance acquisition chip AD5933YRSZ emits a sine wave excitation, which is injected into the tissue to be measured through probe 4. The response of the tissue to be measured is input back to the 5th pin of the AD5933YRSZ through probe 4 again. The 15th and 16th pins of the impedance acquisition chip AD5933YRSZ are connected to the 1st pin of the boost chip ETA1061 to ensure the power supply range and power supply stability of the operational amplifier chip; the 15th and 16th pins of the impedance acquisition chip AD5933YRSZ are also connected to the 43rd and 45th pins of the main control chip STM32F411CEU6, and use the I2C protocol to communicate and send impedance data and receive instructions;

[0048] Pins 12, 13, and 14 of the impedance acquisition chip AD5933YRSZ are all connected to the AGND terminal of the first magnetic bead chip inductor GZ1608U600TF;

[0049] Pins 10 and 11 of the impedance acquisition chip AD5933YRSZ are both connected to one end of the second magnetic bead patch inductor GZ1608U600TF that outputs a +5V analog voltage;

[0050] The 9th pin of the impedance acquisition chip AD5933YRSZ is also connected to the power supply VCC;

[0051] The 5th and 6th pins of the impedance acquisition chip AD5933YRSZ are connected to the probe 4; the impedance acquisition chip AD5933YRSZ has a built-in DDS, and its 6th pin outputs a sine wave signal excitation of a certain frequency, which is injected into the tissue to be tested through the probe 4, and after passing through part of the tissue to be tested, it returns to the 5th pin of the main control chip STM32F411CEU6 through the probe 4 again, and obtains the electrical impedance signal under the corresponding frequency excitation through signal amplification, low-pass filtering, analog-to-digital conversion, and discrete Fourier transform (DFT), and communicates with the main control chip STM32F411CEU6 through the I2C protocol, and transmits the impedance acquisition result back to the main control chip STM32F411CEU6.

[0052] As preferred in this embodiment, Figure 10 As shown, the buzzer 7 is a passive buzzer 7, the first pin of the buzzer 7 is connected to the power supply VCC; the second pin of the buzzer 7 is connected to the collector of the transistor S9018; the emitter of the transistor S9018 is grounded GND; the base of the transistor S9018 is connected to the 29th pin of the main control chip STM32F411CEU6, and the main control chip drives the transistor S9018 by issuing PWM. When the identification results are different, the main control chip issues different PWM frequencies, and the buzzer 7 emits different tones as a sound reminder of the identification results.

[0053] As preferred in this embodiment, Figure 10 As shown, the LED light group 8 includes 3 LED lights, which are respectively connected to the 10th, 11th and 12th pins of the main control chip STM32F411CEU6; and the first LED light is also connected to the power supply VDD. Different tissue identification results will flash LED lights of different colors and guide light through corresponding light guide columns to serve as visual feedback of the tissue identification results.

[0054] The above embodiments and descriptions are only for explaining the principles and best embodiments of the present invention. Without departing from the spirit and scope of the present invention, the present invention may be subject to various changes and improvements, which shall fall within the scope of the invention to be protected.

Claims

1. A pedicle screw implantation device based on bioelectrical impedance guidance, characterized by: The invention comprises a handle (1), a sleeve (2), a connecting rod (3), and a probe (4); the sleeve (2) is detachably connected to the sleeve (2); a probe (4) is further provided in the handle (1) and the sleeve (2); a connecting rod (3) is further sleeved on the lower end of the probe (4); a pedicle screw (9) is detachably connected to one end of the connecting rod (3); the lower end of the probe (4) extends from the lower end of the pedicle screw (9) and contacts the tissue to be measured; an electrical impedance acquisition system is provided in the handle (1), and the electrical impedance acquisition system is electrically connected to the probe (4).

2. The bioelectrical impedance-guided pedicle screw implantation device according to claim 1, characterized in that: The electrical impedance acquisition system comprises a main control unit (5), a power supply circuit, an impedance acquisition circuit, a buzzer (7) and an LED light group (8) connected to the main control unit (5); the impedance acquisition circuit acquires the electrical impedance value of the tissue to be measured through a probe (4) and returns the acquired impedance information to the main control unit (5); the main control unit (5) classifies the tissue according to the impedance information and feeds back the identification result to the user in the form of sound and light through the LED light group (8) and the buzzer (7).

3. The bioelectrical impedance-guided pedicle screw implantation device according to claim 2, characterized in that: The calculation formula of the electrical impedance value Z is as follows: Where R0 represents the resistance at zero frequency; R ∞ represents the resistance at infinite frequency; s is the angular frequency; C ∞ is a constant related to the behavior of biological tissue; α represents the degree of dispersion of the polarization process of biological tissue.

4. The bioelectrical impedance-guided pedicle screw implantation device according to claim 2, characterized in that: The main control unit (5) adopts a main control chip of model STM32F411CEU6.

5. The bioelectrical impedance-guided pedicle screw implantation device according to claim 4, characterized in that: The power supply circuit includes a 4.2V lithium battery (6), a boost circuit, a digital power supply, and an analog power management circuit; the 4.2V lithium battery (6) is used to ensure long-term safe operation of the battery through a lithium battery protection chip with a model number of XB4908, and the system can be powered by turning on the toggle switch SS-12D01-G6; the 4.2V lithium battery (6) is connected to the digital power supply and the analog power management circuit through the boost circuit, and is boosted to 5V by the boost circuit to power the impedance acquisition circuit.

6. The bioelectrical impedance-guided pedicle screw implantation device according to claim 5, characterized in that: The first and second pins of the lithium battery protection chip XB4908 are respectively connected to the positive electrode VBAT+ and the negative electrode VBAT- of the 4.2V lithium battery (6); the positive electrode VBAT+ of the 4.2V lithium battery (6) is connected to the toggle switch SS-12D01-G6; the positive electrode VBAT+ and the negative electrode VBAT- of the 4.2V lithium battery (6) are also connected to the battery holder BX-PH2.0-2PZZ.

7. The bioelectrical impedance-guided pedicle screw implantation device according to claim 6, characterized in that: The boost circuit includes a boost chip ETA1061, the 6th pin of the boost chip ETA1061 is connected to the 3rd pin of the toggle switch SS-12D01-G6; the 1st pin of the boost chip ETA1061 outputs a 5V voltage; and the 3rd pin of the boost chip ETA1061 is connected to the 14th pin of the main control chip STM32F411CEU6; resistors R29 and R28, and capacitors C20 and C19 are also connected between the 1st, 2nd and 5th pins of the boost chip ETA1061; the 6th and 4th pins of the boost chip ETA1061 are also connected to the ground GND.

8. The bioelectrical impedance-guided pedicle screw implantation device according to claim 7, characterized in that: The digital power supply and analog power management circuit includes two magnetic bead chip inductors GZ1608U600TF; the two ends of the first magnetic bead chip inductor GZ1608U600TF are connected to GND and AGND respectively; one end of the second magnetic bead chip inductor GZ1608U600TF is connected to the first pin of the boost chip ETA1061, and the other end outputs a +5V analog voltage. The analog power supply and the digital power supply part are isolated by the magnetic bead chip inductors.

9. The bioelectrical impedance-guided pedicle screw implantation device according to claim 8, characterized in that: The impedance acquisition circuit includes an impedance acquisition chip AD5933YRSZ, and the 15th and 16th pins of the impedance acquisition chip AD5933YRSZ are connected to the 1st pin of the boost chip ETA1061; the 15th and 16th pins of the impedance acquisition chip AD5933YRSZ are also connected to the 43rd and 45th pins of the main control chip STM32F411CEU6; Pins 12, 13, and 14 of the impedance acquisition chip AD5933YRSZ are all connected to the AGND terminal of the first magnetic bead patch inductor GZ1608U600TF; Pins 10 and 11 of the impedance acquisition chip AD5933YRSZ are both connected to one end of the second magnetic bead patch inductor GZ1608U600TF that outputs a +5V analog voltage; The 9th pin of the impedance acquisition chip AD5933YRSZ is also connected to the power supply VCC; The 5th and 6th pins of the impedance acquisition chip AD5933YRSZ are connected to the probe (4); and the chip communicates with the main control chip via the I2C protocol, and transmits the impedance acquisition result back to the main control chip.

10. The bioelectrical impedance-guided pedicle screw implantation device according to claim 9, characterized in that: The buzzer (7) is a passive buzzer. The first pin of the buzzer (7) is connected to the power supply VCC; the second pin of the buzzer (7) is connected to the collector of the transistor S9018; the emitter of the transistor S9018 is grounded GND; the base of the transistor S9018 is connected to the 29th pin of the main control chip STM32F411CEU6, and the main control chip drives the transistor S9018 by issuing PWM; The LED light group (8) includes three LED lights, which are respectively connected to the 10th, 11th and 12th pins of the main control chip STM32F411CEU6; and the first LED light is also connected to the power supply VDD. Different tissue recognition results flash the LED lights of different colors.

Images