A surgical suture preparation system and method based on a slipknot with controllable knot-tying force

Abstract

The present application relates to a kind of knotting force controllable surgical suture preparation system and method based on active knot, weave specific topological structure active knot controller at surgical suture end, input the desired knotting force to the preset force calculation system based on finite element algorithm, and preset force is calculated by force control stretching device, preset force is loaded in active knot controller preforce stress end, until active knot controller reaches predetermined load, and the preparation of knotting force controllable surgical suture is completed.The present application can accurately control the size of knotting force in actual suture knotting operation, avoid the tissue cutting, ischemia caused by knotting force too large and the tissue leakage caused by knotting force too small.In the process of suturing, clear mechanical signal can be provided to surgeon, improve the consistency and accuracy of knotting operation, also enable low seniority doctor to complete high-quality knotting.

Description

Technical Field

[0001] This invention belongs to the field of medical surgical instrument technology, and in particular to a surgical suture preparation system and method based on a slipknot with controllable knotting force. Background Technology

[0002] Suturing is a fundamental and crucial procedure in surgery. In surgery, tying knots in surgical sutures at the wound site achieves hemostasis, wound closure, and the anastomosis of severed tissues. After suturing, the sutures need to be tightened to secure the wound. Clinically, the force exerted to tighten the sutures is called the knot force. The magnitude of the knot force directly affects the quality of the suture, thus determining the success or failure of the surgery. The appropriate knot force depends heavily on the surgeon's individual clinical experience and varies considerably from person to person.

[0003] In gastrointestinal anastomosis surgery, excessive knot force can lead to tissue ischemia and necrosis, or even cut the tissue, causing suture failure and leakage. Insufficient knot force results in incomplete anastomosis closure, or even local gaps, making it difficult to withstand the pressure of fluids within the gastrointestinal tract and causing leakage. Suturing with appropriate knot force provides suitable tension to the anastomosed gastrointestinal tissues, allowing them to heal with sufficient blood supply and without leakage of digestive juices.

[0004] In laparoscopic surgery, surgeons insert long, rod-shaped laparoscopic instruments through small incisions in the abdominal cavity to perform surgical procedures. Compared to traditional open surgery, laparoscopic surgery reduces trauma but also places higher demands on the surgeon's skills. In traditional open surgery, surgeons can directly pull the ends of the sutures with both hands, intuitively feeling and controlling the knot force. However, when using laparoscopic instruments, the surgeon's sensitivity to the contact force of the instrument ends is greatly limited, making it difficult to precisely control the knot force.

[0005] Surgical robots offer greater freedom and more precise control compared to laparoscopic instruments. However, most surgical robots currently in clinical use employ displacement control and lack force feedback capabilities. Consequently, surgeons performing remote operations cannot perceive and control the magnitude of the knotting force, leading to suture failure.

[0006] In conclusion, whether it is traditional open surgery, minimally invasive laparoscopic surgery, or surgical robots, all face the problem of precisely controlling the knot-tying force.

[0007] Chinese patent CN202122748479 provides a tension-precision adjustable knob-type wound closure device, including a knob assembly, a base, a nylon steel rope, guide buckles, and a film. The base has a central rotating hole, and a sponge film is placed at the bottom. The knob assembly includes a knob and a rotating shaft, with the rotating shaft fixedly installed at the center of the knob and located within the rotating hole of the base. The rotating shaft and the rotating hole of the base are rotatably connected. The film is a rectangular sheet, and there are two sheets. Multiple guide buckles are symmetrically fixedly installed on the two sheets of film. Each guide buckle consists of an upper buckle cover, a lower buckle cover, and a guide buckle shaft. The lower buckle cover is fixedly installed on the film, and the guide buckle shaft is located between the upper and lower buckle covers. The advantages of this invention are that it can quickly close wounds, is not limited by the shape and size of the wound, reduces the risk of wound infection, precisely adjusts pressure to promote wound healing, leaves no sutures at the wound closure point, and leaves no obvious scars after healing.

[0008] However, the above-mentioned solutions have obvious shortcomings.

[0009] First, this device can only be used for closing skin wounds, and is not suitable for deep wounds or anastomosis of internal abdominal organs. This is because the knobs, base, nylon steel ropes, and other components in the device are not biodegradable or biocompatible, and will cause severe allergic reactions when applied to the inside of a living organism.

[0010] Second, the above-mentioned device cannot be used in laparoscopic and robotic surgery because the size of the device is much larger than the size of the abdominal opening in laparoscopic minimally invasive surgery, and it cannot be entered into the patient's abdominal cavity through the abdominal opening.

[0011] Third, the aforementioned device cannot adjust the tension at individual points along the wound closure line; it can only adjust the tension across the entire wound. In clinical experience, most wounds are not linear but irregular, sometimes even with tissue loss. Therefore, the required closure tension varies at each point along the wound. In the knob device, the nylon cord connects the knob assembly and the guide buckle, making the tension along the nylon cord direction similar. This device is relatively reliable for regular wounds such as lacerations, but when dealing with irregular wounds such as impact injuries and contusions, it is difficult to adjust the tension at each point along the wound direction individually, thus failing to achieve closure for these common wounds.

[0012] Fourth, the device is connected to the tissue by sponge mucosa, which provides very limited wound closure force. Although it can achieve wound closure without the use of sutures, the cost is that it cannot provide mechanical strength comparable to sutures. Summary of the Invention

[0013] The purpose of this invention is to overcome the shortcomings of existing technologies and propose a surgical suture preparation system and method based on a slipknot with controllable knotting force. This system enables precise control of the slipknot controller's opening force during actual suturing operations, avoiding tissue cutting and ischemia caused by excessive knotting force, as well as tissue leakage risks caused by insufficient knotting force. Simultaneously, it provides clear mechanical signals to the surgeon during suturing, improving the consistency and accuracy of the suturing operation and enabling junior surgeons to achieve high-quality suturing.

[0014] The technical problem solved by this invention is achieved through the following technical solution:

[0015] A surgical suture preparation system based on a slipknot with controllable knotting force includes a slipknot controller with a specific spatial geometry, a precision force-controlled stretching device, and a pre-set force calculation system. The end of the slipknot controller and the pre-set force receiving end are connected to the precision force-controlled stretching device by clamping. The pre-set force calculation system can calculate the magnitude of the pre-set force corresponding to a specific slipknot opening force. The precision force-controlled stretching device can apply the corresponding pre-set force to the slipknot controller with the specific spatial geometry, thereby giving the slipknot controller a preset large opening force.

[0016] Furthermore, the slipknot controller, with its specific spatial geometry, is a pullable knot woven at the end of the surgical suture, including but not limited to fisherman's knots, slip knots, and hitching knots. A pre-set force of a specified magnitude is applied to obtain a slipknot controller with a specific opening force. The force-bearing structure of the slipknot controller includes a pre-set force end, an opening force end, and the end of the suture. Applying tension to the pre-set force end and the end of the suture can lock the slipknot controller; applying tension to the opening force end and the end of the suture can untie the slipknot controller, ultimately restoring it to a linear shape.

[0017] Furthermore, the precise force-controlled stretching device can stably clamp the force-bearing structure of the sew knot controller and apply a preset load, and can maintain the load for any duration. The two ends of the precise force-controlled stretching device are clamping devices that are not limited to pneumatic tooling. The clamping devices at both ends of the precise force-controlled stretching device clamp the preset force-bearing end and the end of the thread in the force-bearing structure of the sew knot controller to prepare a sew knot controller with a specified output force; or clamp the opening force-bearing end and the end of the thread in the force-bearing structure to determine the output force of the sew knot controller. The clamping inner side of the clamping device is provided with an anti-slip structure to prevent slippage during the clamping of the surgical suture.

[0018] Moreover, the wires used in the live knot controller are not limited by diameter or material, including but not limited to silk, polylactic acid, polyglycolic acid, polyglycolic acid, polyglycolic acid, polypropylene, or collagen.

[0019] Moreover, the preset force calculation system calculates the preset force based on the output force of the required live knot controller, the spatial geometry, and the material parameters of the wire.

[0020] Moreover, the preset force is the force that stretches the knot controller to a predetermined load and maintains the load through the preset force receiving end and the end of the wire of the knot controller.

[0021] A method for preparing a surgical suture preparation system with controllable knotting force based on slipknots includes the following steps:

[0022] Step 1: Based on the spatial geometry of the slipknot controller, use surgical sutures to weave an untightened slipknot with that structure;

[0023] Step 2: Clamp the end of the thread with the slipknot prepared in Step 1 and the end of the slipknot control preset force on the precision force control tensioning device respectively;

[0024] Step 3: Input the required knot opening force, knot geometry parameters, and surgical suture material parameters into the preset force calculation system to calculate the preset force;

[0025] Step 4: The precision force-controlled tensioning device applies the preset force obtained in step 3 to the knot controller and holds the load to obtain a knot controller with a specific opening force.

[0026] Step 5: Clamp the opening force control end and the end of the wire of the slack knot controller with specific opening force prepared in Step 4 into the precision force control stretching device, and measure the magnitude of the slack knot opening force.

[0027] Step 6: Compare the measured value of the knot opening force obtained in Step 5 with the preset value of the required knot opening force, optimize the preset force calculation system in Step 3, and repeat Steps 1-5 until the measured value is the same as the preset value.

[0028] The advantages and positive effects of this invention are:

[0029] 1. This invention constructs a slipknot controller within the surgical suture. The required knotting force is input into a pre-force calculation system to obtain the pre-force. A precise force-controlled tensioning device applies the pre-force to the pre-force receiving end of the slipknot controller until the controller reaches the predetermined load, thus completing the preparation of a surgical suture with controllable knotting force. This invention enables precise control of the knotting force during actual suturing operations, avoiding tissue cutting and ischemia caused by excessive knotting force, as well as tissue leakage risks caused by insufficient knotting force. During suturing, it provides clear mechanical signals to the surgeon, improving the consistency and accuracy of the suturing operation, and enabling junior surgeons to achieve high-quality suturing.

[0030] 2. The suturing controller of this invention can provide mechanical signals through visual feedback in clinical operations such as laparoscopic surgery and robotic surgery where there is no direct tactile feedback, making the suturing operation of clinicians more precise. In robotic surgery, the end effector of the robotic arm mostly lacks a force feedback system, which makes it difficult for clinicians to perform remote operations (such as...). Figure 9 When the robotic arm loses direct perception of the tissue's softness and hardness and the suture's stretching state, as shown in the diagram, the driving force and gripping force of the robotic arm are much greater than those of a human hand. Therefore, in this state, knots are often tied too tightly, leading to suture breakage or even tissue cutting. The slipknot controller, while providing force-visual feedback to clinicians, can work with the robotic arm to automatically unload after reaching a preset load, thus preventing suture breakage and tissue cutting.

[0031] 3. The knotting force provided by the slipknot controller of this invention can be adjusted to adapt to the suturing needs of different tissues. By measuring the optimal knotting force for different tissues, precise suturing of various tissues can be achieved. Furthermore, due to the significant individual differences in patient tissues, the adjustable knotting force also provides a basis for personalized medicine.

[0032] 4. The slipknot controller of the present invention can achieve accurate knotting force control solely through the slipknot structure without adding any sensors. After the function is achieved, the slipknot is untied, and there is no difference in structure and composition from conventional sutures. Its biocompatibility and safety are substantially equivalent to those of the original sutures.

[0033] 5. The slipknot controller of the present invention achieves its function by relying on its own braiding structure. Its main cost lies in the construction of the precise force control tension device and the programming of the pre-set force calculation system. After it is put into use, the cost of adding the slipknot controller can be ignored when spread over the production of large batches of slipknot sutures.

[0034] 6. The live knot driver of the present invention is a universal construction strategy applicable to various types of sutures, compatible with existing surgical sutures already in clinical use, and does not affect the surgeon's operating habits during use. Attached Figure Description

[0035] Figure 1 Diagram of a two-loop fishing knot slipknot controller;

[0036] Figure 2 This is a schematic diagram showing the force applied when the live knot controller is released.

[0037] Figure 3 Force-displacement curves and state diagrams when the live knot controller is untied;

[0038] Figure 4 This simulates the moment a slipknot is opened during robotic surgery.

[0039] Figure 5 A schematic diagram of the process decomposition for constructing the spatial structure of the live knot controller;

[0040] Figure 6 This is a schematic diagram of the slipknot spatial structure (two loops - fishing knot) and the finished product;

[0041] Figure 7 A schematic diagram of the tensioning joint of the precision force control tensioning device;

[0042] Figure 8 This is a diagram of the preset force calculation system of the present invention;

[0043] Figure 9 This is a schematic diagram of remote operation of a surgical robot.

[0044] Figure 10 This is a schematic diagram of the live knot controller in an embodiment of the present invention;

[0045] Figure 11 This is a schematic diagram of the pre-set force calculation system and silicone suture practice module in an embodiment of the present invention;

[0046] Figure 12 A schematic diagram of a winding plate for constructing a live-knot topology in an embodiment of the present invention;

[0047] Figure 13 A comparison diagram of the stitching effect between ordinary sutures and sutures with a slipknot controller in an embodiment of the present invention;

[0048] Figure 14 An in vitro intestinal perforation suturing test device in this embodiment of the invention. Detailed Implementation

[0049] The present invention will be further described in detail below with reference to the accompanying drawings.

[0050] A surgical suture preparation system based on a slipknot with controllable knotting force includes a slipknot controller, a precision force-controlled stretching device, and a pre-set force calculation system. The suture tail end of the slipknot controller and the pre-set force receiving end of the slipknot controller are respectively connected to the precision force-controlled stretching device. The precision force-controlled stretching device is connected to the pre-set force calculation system, and the results calculated by the pre-set force calculation system are used to activate the slipknot controller.

[0051] like Figure 1 As shown, the slipknot controller is a slipknot structure with a specific spatial geometry, woven into the end of the surgical suture using a one-, two-, or three-loop fishing knot or other structures. The pre-set force-bearing end of the slipknot controller is the force-bearing end of the slipknot, such as... Figure 2 and Figure 3As shown, the slipknot unties itself when the tensile load reaches a specific preset value, restoring its original linear shape. This specific preset value is determined by both the preset force and structural parameters. The load is cut off the instant the slipknot unties, thus preventing the suture from applying a load to the biological tissue exceeding the preset value; hence, it is called its controller. The untying of the slipknot simultaneously provides mechanical feedback and control functions both visually and tactilely. Visually, the process of the slipknot untying is a very clear visual signal, whether in open surgery, laparoscopic surgery, or robotic surgery.

[0052] like Figure 4 As shown, in laparoscopic and robotic surgery, the visual magnification effect of the endoscope makes the size of the nodule observed by the surgeon on the display screen much larger than its actual size, thus making the visual signal more obvious.

[0053] During robotic surgery, thanks to the intervention of robotic arms and machine vision systems, the robot can automatically stop stretching the slipknot when it recognizes the visual signal that the slipknot has been untied, thus avoiding overloading and suture breakage. Tactilely, a noticeable gap appears the moment the slipknot is untied. In open and laparoscopic surgery, the hand can directly feel this gap and stop stretching the suture, thus avoiding excessive knotting force. In robotic surgery, this gap can also be sensed remotely by the surgeon.

[0054] like Figure 5 and Figure 6 As shown, the suture winding plate allows the surgical suture to be wound along the grooves on the surface of the plate to reproduce the spatial structure of the required slipknot controller, thereby ensuring the repeatability and consistency of the slipknot controller.

[0055] like Figure 7 As shown, the precision force-controlled stretching device is a uniaxial stretching device that applies a specific preset load. Both ends of the device are clamping devices, which respectively clamp the surgical suture at one end of the suture controller and the pre-force receiving end of the suture controller. The inner sides of the clamping devices are equipped with anti-slip structures to prevent displacement of the suture during clamping. The preset force is the force used to stretch the suture controller to a predetermined load through the suture tail end and the pre-force receiving end of the suture controller.

[0056] like Figure 8 As shown, the pre-setting force is obtained by reversing the required opening force based on the pre-setting force calculation system. Through this calculation system, after inputting the required knotting force, the corresponding pre-setting force can be obtained. Then, the pre-setting force is input into the force-controlled tensioning device to obtain a slack knot controller with a specific knotting force.

[0057] A method for preparing a surgical suture preparation system with controllable knotting force based on slipknots includes the following steps:

[0058] Step 1: Based on the spatial geometry of the slipknot controller, use surgical sutures to weave an untightened slipknot with that structure;

[0059] Step 2: Clamp the end of the thread with the slipknot prepared in Step 1 and the end of the slipknot control preset force on the precision force control tensioning device respectively;

[0060] Step 3: Input the required knot opening force, knot geometry parameters, and surgical suture material parameters into the preset force calculation system to calculate the preset force;

[0061] Step 4: The precision force-controlled tensioning device applies the preset force obtained in step 3 to the knot controller and holds the load to obtain a knot controller with a specific opening force.

[0062] Step 5: Clamp the opening force control end and the end of the wire of the slack knot controller with specific opening force prepared in Step 4 into the precision force control stretching device, and measure the magnitude of the slack knot opening force.

[0063] Step 6: Compare the measured value of the knot opening force obtained in Step 5 with the preset value of the required knot opening force, optimize the preset force calculation system in Step 3, and repeat Steps 1-5 until the measured value is the same as the preset value.

[0064] Based on the above-mentioned surgical suture preparation system and method with controllable knotting force based on slipknot, the effectiveness of the present invention was verified through experiments.

[0065] Example 1:

[0066] like Figure 10 As shown, this embodiment uses standard 4-0 suture thread ( Figure 10-1 ), ring-fishing knot knotting board ( Figure 10-2 Precision force-controlled tensioning device, Figure 10-4 and Figure 10-5 ), Preset force calculation system ( Figure 11 (Left image) and silicone stitching test module ( Figure 11 (Right image).

[0067] like Figure 12 As shown, by winding the No. 4-0 sewing thread sequentially along the grooves on the knotting board, the desired slip knot spatial geometry can be obtained. Figure 10-3 Then, the pre-force receiving end and lower left part of the slip knot controller are clamped to the precision force control stretching system. The required knotting force is then input into the pre-force calculation system to obtain the corresponding pre-force magnitude, which is then input into the stretching system for stretching, thereby tightening the slip knot to the desired degree. Figure 10-4 and Figure 10-5Next, a suturing test was conducted using sutures equipped with the slipknot controller. A common silicone suture practice board was used for the test, simulating a 7cm long wound with 0.15mm round holes 0.5cm apart on both sides for needle insertion and exit. A pair of these holes were placed every 1cm along the simulated wound. The surgeon inserted the round needle through the holes and the simulated wound, then applied a slipknot to the wound. The surgeon then stretched both ends of the suture until the slipknot was released; the corresponding knotting force was exactly the preset knotting force.

[0068] Pressure-sensitive paper can visually reflect the pressure exerted by sutures on tissue, thus indirectly evaluating the consistency and repeatability of knot tying. The cut pressure-sensitive paper is placed in a simulated sutured wound. The clinician first sutures the wound using ordinary sutures without a slipknot, then measures the pressure on the corresponding area of ​​the pressure-sensitive paper. The process is then repeated using sutures with a slipknot controller.

[0069] Test results are as follows Figure 13 As shown: Each time, perform five stitches on the silicone suture practice module according to the preset opening. Then, replace the pressure-sensitive paper and collect the pressure values. Repeat the above operation 5 times each using ordinary sutures and slipknot sutures, collect data, and analyze it. The depth of color on the pressure-sensitive paper reflects the amount of pressure applied. The positive pressure value can be read by comparing it with a standard color chart. The positive pressure value marked in the figure is the average pressure of the upper pressure area after each stitch.

[0070] The experimental results show that, in the same suturing operation, the relative pressure error using slipknot sutures is 10.2%, while the relative pressure error using ordinary sutures is as high as 19.4%. The stability and consistency of suturing using slipknot sutures are far superior to those using ordinary sutures.

[0071] Example 2:

[0072] like Figure 14 As shown, the method for preparing the suture with the slipknot controller used in this embodiment is basically the same as that in Example 1. In this embodiment, as... Figure 5 As shown, this technique was applied to an intestinal rupture repair test in SD rats. A 1.5 mm diameter biopsy punch was used to rupture the intestinal structure above the colon in SD rats, followed by suturing with a slipknot suture. When pulling the suture, it was not pulled by hand, but rather stretched using a screw, while a force gauge was used to record the knot force in real time.

[0073] Preliminary verification tests have shown that the optimal knotting force for repairing rat intestinal rupture is 1.30N. Therefore, 1.30N was used as the preset knotting force. By inputting the preset force inverse system, it was found that the required preset force is 0.57N. Five slipknot sutures were prepared using this preset force and then applied to the rat intestinal rupture repair experiment. The knotting force when the slipknot controller was opened was recorded.

[0074] The experimental results show that the knotting force achieved by the slipknot controller differs from the preset value by less than 10%, and in all 5 groups of experiments, it successfully closed the rat intestinal rupture.

[0075] It should be emphasized that the embodiments described in this invention are illustrative rather than limiting. Therefore, this invention includes, but is not limited to, the embodiments described in the specific implementation. Any other implementations derived by those skilled in the art based on the technical solutions of this invention are also within the scope of protection of this invention.

Claims

1. A surgical suture preparation system based on slipknots with controllable knotting force, characterized in that: The device includes a swivel controller with a specific spatial geometry, a precision force-controlled stretching device, and a preload calculation system. The end of the swivel controller and the preload-receiving end are connected to the precision force-controlled stretching device via clamping. The preload calculation system can calculate the magnitude of the preload corresponding to a specific swivel opening force. The precision force-controlled stretching device can apply the corresponding preload to the swivel controller with the specific spatial geometry, thereby giving the swivel controller a preset large opening force. The preload calculation system calculates the preload based on the required output force of the swivel controller, the spatial geometry, and the material parameters of the wire. The preload is the force that stretches the swivel controller to a predetermined load and maintains the load through the preload-receiving end of the swivel controller and the end of the wire.

2. The surgical suture preparation system based on a slipknot with controllable knotting force according to claim 1, characterized in that: The slipknot controller is a pullable knot with a specific spatial geometry. It is woven into the end of the surgical suture, including fisherman's knot, slip knot, and hitching knot. A pre-force of a specified magnitude is applied to obtain a slipknot controller with a specific opening force. The force-bearing structure of the slipknot controller includes a pre-force receiving end, an opening force receiving end, and a thread tail. By applying a pulling force to the pre-force receiving end and the thread tail, the slipknot controller can be locked. By applying a pulling force to the opening force receiving end and the thread tail, the slipknot controller can be untied and finally restored to a linear shape.

3. The surgical suture preparation system based on a slipknot with controllable knotting force according to claim 2, characterized in that: The precise force-controlled stretching device can stably clamp the force-bearing structure of the suture controller and apply a preset load, and can maintain the load for any duration. The two ends of the precise force-controlled stretching device are pneumatic tooling clamping devices. The clamping devices at both ends of the precise force-controlled stretching device clamp the preset force-bearing end and the end of the suture in the force-bearing structure of the suture controller to prepare a suture controller with a specified output force; or clamp the opening force-bearing end and the end of the suture in the force-bearing structure to determine the output force of the suture controller. The clamping inner side of the clamping device is provided with an anti-slip structure to prevent slippage during the clamping of the surgical suture.

4. The surgical suture preparation system based on a slipknot with controllable knotting force according to claim 2, characterized in that: The wires used in the live knot controller are not limited by diameter or material, including silk, polylactic acid, polyglycolic acid, polyglycolic acid, polyglycolic acid, polypropylene, or collagen.

5. A method for preparing a surgical suture preparation system with controllable knotting force based on a slipknot as described in any one of claims 1 to 4, characterized in that, Includes the following steps: Step 1: Based on the spatial geometry of the slipknot controller, use surgical sutures to weave an untightened slipknot with that structure; Step 2: Clamp the end of the thread with the slipknot prepared in Step 1 and the end of the slipknot control preset force on the precision force control tensioning device respectively; Step 3: Input the required knot opening force, knot geometry parameters, and surgical suture material parameters into the preset force calculation system to calculate the preset force; Step 4: The precision force-controlled tensioning device applies the preset force obtained in step 3 to the knot controller and holds the load to obtain a knot controller with a specific opening force. Step 5: Clamp the opening force control end and the end of the wire of the slack knot controller with specific opening force prepared in Step 4 into the precision force control stretching device, and measure the magnitude of the slack knot opening force. Step 6: Compare the measured value of the knot opening force obtained in Step 5 with the preset value of the required knot opening force, optimize the preset force calculation system in Step 3, and repeat Steps 1-5 until the measured value is the same as the preset value.

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