CN104083204B - A kind of tibial tunnel locating device based on personalized navigation template and method thereof - Google Patents

Abstract

The invention relates to a tibial tunnel positioning device and method based on a personalized navigation template in cruciate ligament reconstruction surgery. Firstly, the patient's CT and MRI data are collected, the data model is processed and three-dimensionally reconstructed, and then the tunnel is measured and determined according to the three-dimensional model. Position, segment the bone surface required for positioning and establish a navigation template model, then process and prepare it through rapid prototyping technology, and finally use the navigation template combined with the positioning device of the guide for positioning and verification, and then drill into the Kirschner wire. The positioning of the navigation template of the present invention is simple and easy to operate, coupled with the auxiliary positioning and calibration of the guide, it prevents the small-angle swing deviation of the guide template catheter caused by factors such as soft tissue residues from being magnified when the Kirschner wire is drilled into the inner mouth of the tunnel. It can effectively guarantee the positioning accuracy and make the operation effect more reliable.

Description

A tibial tunnel positioning device and method based on personalized navigation template

technical field

The invention belongs to the technical field of computer-aided medical operations, and relates to an intraoperative tibial tunnel positioning and navigation technology during cruciate ligament reconstruction, in particular to an intraoperative tibial tunnel positioning device and method based on a personalized navigation template during cruciate ligament reconstruction.

Background technique

With the development of transportation technology and the improvement of sports competition level, the cases of knee cruciate ligament tear caused by high energy injury continue to increase. The cruciate ligament of the knee is very important to maintain the stability of the knee joint. If it is not repaired effectively, it may lead to serious consequences such as meniscus damage, cartilage wear, accelerated knee degeneration and osteoarthritis. However, due to its own biological Due to environmental and blood supply characteristics, the self-healing ability of the knee cruciate ligament is extremely poor, so surgical reconstruction has become the main means and method for repairing knee cruciate ligament injuries. According to survey data, there are about 100,000 knee cruciate ligament injuries in the United States every year. reconstructive surgery.

Arthroscopic knee cruciate ligament reconstruction has become the most popular surgical method due to its advantages of less tissue trauma and low infection rate, no obvious postoperative complications and fast recovery, but the literature shows that its success rate is only 65%. % to 90%, the revision rate is as high as 10% to 20%, and the incorrect tunnel position is one of the main reasons for the high failure rate.

In the prior art, there are mainly the following methods for assisting tunnel positioning during cruciate ligament reconstruction of the knee joint:

1. The patent authorization announcement number is CN101919720A described the anterior and posterior cruciate ligament femoral side tunnel locator of the knee joint. The guider roughly determines the tunnel position and performs drilling. Due to individual differences, there are large differences in the shape and size of bones and the anatomical position of ligaments for each person. At the same time, there is a large difference between the structure of the knee joint under the arthroscopic view and the actual situation. Therefore, the accuracy of the tunnel positioning method mainly depends on Depending on the experience and operation of the surgeon during the operation, the positioning accuracy and direction of the tunnel cannot be controlled.

2. The patent authorization announcement number is CN101518447A, a method for improving the accuracy of a computerized navigation system for spinal surgery. Tracers are installed on the spine, surgical tools and instruments, and intelligent navigation instruments. After registration, they are recognized by the navigation system and establish the relationship between them. The location of the operation area of the patient is obtained through the camera, and the digital image of the operation area is obtained before or during the operation and imported into the navigation system for image registration. The navigation system tracks the operation process in real time and displays it synchronously to assist tunnel positioning. The navigation system equipment is complicated and expensive, the device connection and registration process is time-consuming, the learning curve is long, the operation time is long, the camera and the operation area cannot be blocked, which affects the operation, and there are phenomena such as image "drift", which affects the accuracy of the operation. cause error.

3. The patent authorization announcement number is CN101390773A, a method for making a navigation template that can be used for pedicle positioning. The navigation template uses CT or MRI to collect raw data and import it into the computer to establish a three-dimensional model of the vertebra. After the three-dimensional analysis of the channel, a virtual nail-guiding template is reversely established, and it is manufactured by rapid prototyping. The navigation template only relies on the surface anatomy of the vertebrae for positioning, lacks a corresponding positioning evaluation mechanism, and has low positioning accuracy. The template is fixed by manual pressing, and the vibration of the electric drill during the nail insertion process may cause template positioning deviations. It is only suitable for pedicles. position.

4. The patent authorization announcement number is CN101816590A, a method for making a navigation template for human orthopedic surgery and its negative mold. This method collects the original bone data of the patient's operation and imports it into the computer to establish a three-dimensional bone model, sets the screw positioning rod and The bone surface near the screw location is extracted, the reverse navigation template model is established and the three-dimensional model of the female mold is printed out, and the biological material is poured into the female mold to prepare a biocompatible navigation template. As for the nail-in navigation template, its biological requirements are not high, and the biocompatible navigation template prepared by this method is complicated in process and expensive in preparation cost, and its practicability is insufficient.

To sum up, traditional arthroscopy combined with guides to assist knee cruciate ligament reconstruction does not take into account the individual differences in human skeleton tunnel positioning. The success or failure of the operation depends on the experience and operation of the doctor, while the image navigation technology is expensive and complex. The operation increases the cost, learning curve and operation time of the operation, and the image "drift" will have a certain impact on the accuracy of the operation. The positioning accuracy of the existing navigation template cannot be evaluated, and its stability and safety are insufficient. Therefore, the current There is an urgent need to propose a rapid and high-precision personalized auxiliary cruciate ligament tibial tunnel positioning device and method.

Contents of the invention

Based on the above circumstances, the present invention provides a low-cost, high-precision, easy-to-use personalized auxiliary tool and method for positioning the anterior cruciate ligament tunnel, so as to solve the problem of difficulty in the anatomical positioning of the personalized tunnel in the current prior art.

In order to solve the above technical problems, the technical solution adopted by the present invention is: a tibial tunnel positioning device based on a personalized navigation template, including a navigation template and a guide,

The navigation template includes a base whose inner surface is consistent with the anatomical shape of the contacted bone surface, and a guide tube corresponding to the center of the outer opening of the tunnel is designed on the base, the centerline of the guide tube is coaxial with the centerline of the tunnel, and the number Consistent with the number of reconstructed tunnels; there are internal threads in the guide pipe; several through holes are opened on the base for checking the positioning of the navigation template and fixing the navigation template;

The guide includes an inner rod, an outer rod, a metal conduit and a measuring ruler; one end of the inner rod is a positioning hook, and the other end is an arc-shaped positioning arm whose section is in the shape of a keyway, and the positioning arm is provided with a scale showing the opening angle of the guide ; The upper end of the outer rod is adapted to the positioning arm of the inner rod, which is an arc-shaped chute with a keyway shape in cross section, and is connected with the positioning arm through the first locking screw; the lower end of the outer rod is connected to one side of the middle part of a hollow sleeve ; One end of the metal conduit is provided with an external thread corresponding to the internal thread of the guide tube, and the metal conduit is connected to the guide tube after passing through the sleeve, and the sleeve fixes the metal conduit through the second locking screw; the measuring ruler is a pointed metal rod at one end , the metal rod is provided with a scale corresponding to the distance from the positioning hook to the tip, which is used to measure the distance of the tunnel.

The first locking screw is installed on the platform inside the upper end of the outer rod, and the second locking screw is installed on the platform at the lower part of the sleeve.

The wall thickness of the base is 2-3mm, the nominal diameter of the internal thread of the guide pipe is 4mm, the internal diameter of the hollow sleeve is 4mm, and the length is 30mm, the nominal diameter of the external thread of the metal conduit is 4mm, the internal diameter of the metal conduit is 2mm, and the wall thickness is 1mm, and the diameter of the measuring ruler is 3.4mm.

A positioning method adapted to the described tibial tunnel positioning device based on a personalized navigation template, comprising the following steps:

Step 1: Collect the CT data of the patient’s knee joint in straight position, extract and export the tibial and femoral point data with clear outlines;

Step 2: Collect the MRI data of the patient's knee joint in straight position, extract and export point data including the tibia, femur, meniscus, cartilage and cruciate ligament;

Step 3: Sampling, removing noise, denoising and smoothing the data obtained in Step 1 and Step 2, respectively performing 3D reconstruction and obtaining femoral and tibial knee joints with meniscus, cartilage and cruciate ligament tissue structures through registration Model;

Step 4: If the patient’s left and right knee joints have no distortion and good symmetry, then determine the anatomical position of the attachment point of the cruciate ligament on the healthy side according to the 3D model of the healthy side’s knee joint and measure it, and then combine the measurement data of the healthy side with the 3D model of the affected side Both are used to determine the position of the inner opening of the tibial tunnel on the affected side; otherwise, the position of the inner opening of the tibial tunnel is determined directly based on the three-dimensional model of the knee joint on the affected side and combined with empirical data;

Step 5: According to the position of the tunnel inner mouth determined in Step 4, carry out 3D design and analysis of the virtual tunnel, and segment the bone surface required for positioning, establish a navigation template model in the industrial 3D CAD software, and then process and prepare it by rapid prototyping technology come out;

Step 6: The navigation template assists in the positioning of the guide. At the same time, the positioning accuracy of the navigation template is checked by the measuring ruler of the guide. If the error exceeds the standard, the navigation template can be fine-tuned until it meets the surgical requirements.

In the described step four, the tibial cruciate ligament attachment point measurement method is to use the tibial cruciate ligament attachment point to the tibial anterior edge and the inner edge of the distance of the tibial anterior edge and the percentage of the total distance of the inner and outer edges in the cross-sectional direction of the computer three-dimensional model. method;

In Step 5, the three-dimensional design and analysis of the virtual tunnel mainly includes establishing a virtual tunnel in the computer, and then analyzing whether the designed position of the inner mouth of the tunnel will cause a Impact and "wiper effect" and "rubber band effect" after ligament reconstruction, measure whether the length and direction of the tunnel are reasonable; the rapid prototyping technology described is fused deposition modeling or photocuring molding or selective laser sintering.

Described step six includes the following specific steps:

(i) Use the navigation template to fit on the bone surface, and perform preliminary positioning based on the geometry of the bone;

(ii) The navigation template and the metal catheter are fixedly connected by threads, and the outer rod and the metal catheter are connected at the sleeve to guide the preliminary positioning of the positioning hook of the guide in the knee joint. reach the ideal position;

(iii) Keep the position of the positioning hook in step (ii) unchanged, remove the metal conduit, and use a measuring ruler to measure the distance from the center point of the outer opening of the tunnel and the center points of several through holes on the base to at least four different points to the positioning hook , and compare it with the measured value of the computer, if they are consistent, it means that the positioning of the navigation template is accurate;

(iv) Use a short Kirschner wire to drive into the through hole on the base to fix the navigation template, so as to avoid deviation caused by vibration when the Kirschner wire drills into the tibia;

(v) Remove the measuring ruler and install the metal catheter again to guide the drilling into the Kirschner wire.

The present invention also claims to protect the application of the positioning device in tibial tunnel positioning in single-bundle or double-bundle reconstruction of anterior and posterior cruciate ligaments.

A tibial tunnel positioning device and method based on a personalized navigation template proposed by the present invention combines computer imaging reconstruction technology and rapid prototyping technology, fully utilizes the imaging advantages of both CT and MRI, and can obtain , cartilage, cruciate ligament tissue structure and a complete knee joint model with clear outlines of tibia and femur provide a reliable reference for accurate measurement and positioning of the virtual tunnel. Based on the anatomical shape of the bone and the virtual analysis of the preoperative tunnel, the personalized template design is completed, and the preoperative rapid prototyping technology is used to make the positioning simple and easy to operate, which can effectively improve the success rate of the operation and shorten the operation time. Coupled with the auxiliary positioning and calibration of the guide, it prevents the small-angle swing deviation of the guide template catheter caused by factors such as soft tissue residues from being magnified when the Kirschner wire drills into the inner mouth of the tunnel, effectively ensuring the positioning accuracy and making the operation effect more effective. reliable.

Description of drawings

Fig. 1 is a flow chart of the preparation process of the navigation template according to the present invention.

Fig. 2 is an overall schematic diagram of the positioning device of the present invention.

Fig. 3 is a schematic diagram of a navigation template according to the present invention.

Fig. 4 is a schematic diagram of the assembly of the guider according to the present invention.

Fig. 5 is a schematic diagram of the inner rod of the guide according to the present invention.

Fig. 6 is a first schematic view of the outer rod of the guide according to the present invention.

Fig. 7 is a second schematic diagram of the outer rod of the guide according to the present invention.

Fig. 8 is a sectional view of the inner rod positioning arm according to the present invention.

Fig. 9 is a schematic diagram of the metal conduit according to the present invention.

Fig. 10 is a schematic diagram of the measuring ruler of the present invention.

detailed description

A tibial tunnel positioning device and method based on a personalized navigation template according to the present invention will be described in detail below in conjunction with the embodiments and accompanying drawings, but the scope of protection of the present invention is not limited to the following embodiments.

As shown in FIG. 1 , the specific manufacturing process flow of the navigation template of the present invention is carried out in the direction of the arrow.

As shown in Figure 2, the navigation template 1 of the present invention assists the guider 2 in the initial positioning of the inner opening of the tunnel, observes the positioning situation under the arthroscope and fine-tunes the precise positioning, and the metal guide cylinder 5 guides the Kirschner wire to drill in, effectively preventing the outer opening from being guided The small angle error of the tube 12 causes a large deviation in the position of the inner opening.

As shown in Fig. 3, the positioning navigation template 1 of the tibial tunnel for double-bundle reconstruction of the anterior cruciate ligament of the present invention includes a base 11 whose inner surface is geometrically consistent with the bone surface, and a guide tube with an internal thread 13 corresponding to the center of the outer opening of the tunnel. 12 and several through holes 14.

As shown in FIG. 4 , the guide 2 of the present invention includes an inner rod 3 , an outer rod 4 , a metal conduit 5 , a first locking screw 7 and a second locking screw 8 .

As shown in FIG. 5 , the inner rod 3 of the guide 2 of the present invention includes a positioning hook 31 , an arc-shaped positioning arm 32 with a keyway-shaped cross section and a scale 33 thereof.

As shown in Figures 6 and 7, the outer rod 4 of the guide 2 of the present invention includes an arc chute 41 with a keyway shape in section at one end, an upper platform 42 on the inner side of the chute 41, and a hollow sleeve 43 at the other end. Bottom platform 44 of cylinder 43 .

As shown in FIG. 8 , a cross-sectional view of the positioning arm 32 of the inner rod 3 of the present invention.

As shown in FIG. 9 , the metal conduit 5 of the present invention has a threaded external thread 51 with a nominal diameter of 4 mm at one end.

As shown in Figure 10, the measuring ruler 6 of the present invention is a metal rod with a pointed end 61 and a diameter of 3.4 mm. The rod is provided with a measuring scale 62 corresponding to the distance from the positioning hook to the tip, which can be used to measure the distance of the tunnel.

Embodiment one

The steps of the device and method for assisting single-bundle reconstruction of the anterior cruciate ligament in tibial tunnel positioning according to the present invention are as follows:

Step 1: Collect the CT data of the patient's knee joint in straight position, and use the mimics software to extract and export the tibial and femoral point data with clear outlines.

Step 2: Collect the MRI data of the patient's knee joint in straight position, use mimics software to extract point data including tibia, femur, meniscus, cartilage and cruciate ligament and export it.

Step 3: Use imageware to sample the data obtained in Step 1 and Step 2, remove noise points, denoise and smoothen, perform 3D reconstruction respectively, and obtain the femur and tibia with the tissue structure of meniscus, cartilage and cruciate ligament through registration Knee model.

Step 4: In the cross-sectional direction of the computer three-dimensional model, the anatomical position of the attachment point of the cruciate ligament on the healthy side is measured by the percentage of the distance from the attachment point of the tibial cruciate ligament to the anterior edge and the inner edge of the tibia as a percentage of the total distance between the anterior and posterior edges of the tibia and the inner and outer edges of the tibia. The distance between the ligament attachment point and the anterior border and medial border of the tibia was 42.8% of the anteroposterior distance and 45.7% of the medial and medial distance. Combining the measurement data of the healthy side and the three-dimensional model of the affected side to determine the position of the inner opening of the tibial tunnel of the affected side.

Step 5: According to the position of the tunnel determined in step 4, design the tunnel virtually in the computer, and based on the kinematics of the knee joint, the position of the inner mouth of the tunnel will not cause impact after ligament reconstruction. As well as the "wiper effect" and "rubber band effect", the length of the tunnel is 35mm, and the included angle with the tibial plateau is 52°, respectively. The bone surface required for positioning was segmented, and a three-dimensional reverse navigation template 1 model was established in the industrial PRO-E software, which was processed and prepared by selective laser sintering rapid prototyping technology.

Step 6: The navigation template 1 assists the guide 2 in positioning, and at the same time checks the positioning of the navigation template 1 through the measuring ruler 6 of the guide 2 .

Described navigation template 1 comprises a base 11 whose inner surface is consistent with the anatomical form of the contacted bone surface, and its wall thickness is 2 mm; a guide tube 12 corresponding to the center of the outer opening of the tunnel is designed on the base 11, and its centerline is in line with The center line of the tunnel is coaxial, and the number is consistent with the number of reconstructed tunnels; the guide pipe 12 has an internal thread 13 with a nominal diameter of 4 mm; a number of through holes 14 are opened on the base 11, which are used to check the positioning of the navigation template 1 and fix the navigation Template 1.

The guide 2 is composed of an inner rod 3 , an outer rod 4 , a metal conduit 5 and a measuring ruler 6 . Inner rod 3 one end is positioning hook 31, and the other end is the arc positioning arm 32 of keyway shape in section, and positioning arm 32 opening angles are 50 °, and positioning hook 31 and positioning arm 32 are connected by round bar. One end of the outer rod 4 is an arc-shaped chute 41 with a keyway shape in cross section. There is a platform 42 on the inner upper end of the chute 41 on which the first locking screw 7 is installed, and the other end is a hollow sleeve 43 symmetrically distributed on both sides of the center line of the chute 41. On the side, the inner diameter is 4mm, and the length is 30mm. There is a platform 44 on the lower part of the sleeve 43 and two second locking screws 8 are installed. One end of the metal conduit 5 has an external thread 51 with a nominal diameter of 4mm, the inner diameter of the metal conduit 5 is 2mm, and the wall thickness is 1mm. Measuring ruler 6 is a pointed 61 at one end and a metal rod with a diameter of 3.4mm. The rod is provided with a measuring scale 62 corresponding to the distance from the positioning hook 31 to the tip, which can be used to measure the distance of the tunnel.

The specific usage method of step 6 is:

(i) Use the navigation template 1 to fit on the bone surface, and perform preliminary positioning based on the geometry of the bone.

(ii) The navigation template 1 and the metal conduit 5 are fixedly connected through the internal thread 13 and the external thread 51, and the sleeve 43 of the outer rod 4 is coaxially connected with the metal conduit 5 to guide the positioning hook 31 of the inner guide 2 of the knee joint for preliminary positioning, and the joint Observe the position of the positioning hook 31 under the microscope, and fine-tune the template to make the positioning hook 31 reach the ideal position.

(iii) Keep the position of the positioning hook 31 in step (ii) unchanged, remove the metal conduit 5, and measure at least four different points at the center point of the outer mouth of the tunnel and the center points of several through holes 14 on the navigation template 1 by measuring ruler 6 The distance to the tip of the positioning hook 31 is compared with the measured values by the computer. If they are consistent, it means that the positioning of the navigation template 1 is accurate.

(iv) Use a short Kirschner wire to drive into the through hole 14 of the base 11 to fix the navigation template 1, so as to avoid deviation caused by shaking when the Kirschner wire is drilled into the tibia.

(v) Take off the measuring ruler 6 and install the metal conduit 5 again to guide the drilling into the Kirschner wire.

Embodiment two

The steps of the device and method for assisting the positioning of the tibial tunnel for double-bundle reconstruction of the anterior cruciate ligament of the present invention are as follows:

Step 1: Collect the CT data of the patient's knee joint in straight position, and use the mimics software to extract and export the tibial and femoral point data with clear outlines.

Step 2: Collect the MRI data of the patient's knee joint in straight position, use mimics software to extract point data including tibia, femur, meniscus, cartilage and cruciate ligament and export it.

Step 3: Use geomagicstudio to sample the data obtained in step 1 and step 2, remove noise points, denoise and smoothen, perform 3D reconstruction respectively, and obtain femur and tibia with meniscus, cartilage and cruciate ligament tissue structure through registration Knee model.

Step 4: In the cross-sectional direction of the computer three-dimensional model, the anatomical position of the attachment point of the cruciate ligament on the healthy side is measured by the percentage of the distance from the attachment point of the tibial cruciate ligament to the anterior edge and the inner edge of the tibia as a percentage of the total distance between the anterior and posterior edges of the tibia and the inner and outer edges of the tibia. The distance between the anteromedial bundle attachment point and the anterior border and the medial edge of the tibia is 37.3% of the anteroposterior distance and 46.2% of the medial and medial distance, and the distance between the posterolateral bundle attachment point and the anterior border and the medial edge of the tibia is 50.4% and 51.1% of the inside-outside distance. Combining the measurement data of the healthy side and the three-dimensional model of the affected side to determine the position of the inner opening of the tibial tunnel of the affected side.

Step 5: According to the position of the tunnel determined in step 4, design the tunnel virtually in the computer, and based on the kinematics of the knee joint, the position of the inner mouth of the tunnel will not cause impact after ligament reconstruction. As well as the "wiper effect" and "rubber band effect", the lengths of the anteromedial and posterolateral tunnels are 38mm and 31mm, respectively, and the angles with the tibial plateau are 56° and 45°, respectively. The bone surface required for positioning is segmented, and a three-dimensional reverse navigation template 1 model is established in the industrial NX-UG software, which is processed and prepared by fusion deposition rapid prototyping technology.

Step 6: The navigation template 1 assists the guide 2 in positioning, and at the same time checks the positioning of the navigation template 1 through the measuring ruler 6 of the guide 2 .

The navigation template 1 includes a base 11 whose inner surface is consistent with the anatomical shape of the contacted bone surface, and whose wall thickness is 2.5mm; a guide tube 12 corresponding to the center of the outer opening of the tunnel is designed on the base 11, and its centerline It is coaxial with the center line of the tunnel, and the number is consistent with the number of reconstructed tunnels; the guide tube 12 has internal threads 13 with a nominal diameter of 4mm; the base 11 has a number of through holes 14 for checking the positioning and fixing of the navigation template 1 Navigation template 1.

The guide 2 is composed of an inner rod 3 , an outer rod 4 , a metal conduit 5 and a measuring ruler 6 . One end of the inner rod 3 is a positioning hook 31, and the other end is an arc positioning arm 32 with a keyway shape in cross section. The 32 opening angles of the positioning arm are 45°, and the positioning hook 31 and the positioning arm 32 are connected by a round bar. One end of the outer rod 4 is an arc-shaped chute 41 with a keyway shape in cross section. There is a platform 42 on the inner upper end of the chute 41 on which the first locking screw 7 is installed, and the other end is a hollow sleeve 43 symmetrically distributed on both sides of the center line of the chute 41. On the side, the inner diameter is 4mm, and the length is 30mm. There is a platform 44 on the lower part of the sleeve 43 and two second locking screws 8 are installed. One end of the metal conduit 5 has an external thread 51 with a nominal diameter of 4mm, the inner diameter of the metal conduit 5 is 2mm, and the wall thickness is 1mm. Measuring ruler 6 is a pointed 61 at one end and a metal rod with a diameter of 3.4mm. The rod is provided with a scale 62 corresponding to the distance from the positioning hook 31 to the tip, which can be used to measure the distance of the tunnel.

The specific usage method of step 6 is:

(i) Use the navigation template 1 to fit on the bone surface, and perform preliminary positioning based on the geometry of the bone.

(ii) The navigation template 1 and the metal conduit 5 are fixedly connected through the internal thread 13 and the external thread 51, and the sleeve 43 of the outer rod 4 is coaxially connected with the metal conduit 5 to guide the positioning hook 31 of the inner guide 2 of the knee joint for preliminary positioning, and the joint Observe the position of the positioning hook 31 under the microscope, and fine-tune the template to make the positioning hook 31 reach the ideal position.

(iii) Keep the position of the positioning hook 31 in step (ii) unchanged, remove the metal conduit 5, and measure at least four different points at the center point of the outer mouth of the tunnel and the center points of several through holes 14 on the navigation template 1 by measuring ruler 6 The distance to the tip of the positioning hook 31 is compared with the measured values by the computer. If they are consistent, it means that the positioning of the navigation template 1 is accurate.

(iv) Use a short Kirschner wire to drive into the through hole 14 of the base 11 to fix the navigation template 1, so as to avoid deviation caused by shaking when the Kirschner wire is drilled into the tibia.

(v) Take off the measuring ruler 6 and install the metal conduit 5 again to guide the drilling into the Kirschner wire.

Claims (3)

1. the tibial tunnel locating device based on personalized navigation template, it is characterised in that, comprise navigation template and guider;

Described navigation template comprises the internal surface pedestal consistent with the anatomic form of the bone surface contacted, and pedestal is designed with the guide pipe corresponding to Wai Kou center, tunnel, and the medullary ray of guide pipe is coaxial with tunnel medullary ray, and quantity is consistent with reconstruction tunnel number; Internal thread it is provided with in guide pipe; Pedestal has some through holes, for checking the location of navigation template and fixing navigation template;

Described guider comprises interior bar, outer bar, metal tubing and measuring scale; Interior bar one end is location hook, and the arc registration arm of the other end to be cross section be keyway shape, registration arm is provided with the scale of display guider subtended angle; The upper end of outer bar and the registration arm of interior bar adapt, and be a cross section are the arc chute of keyway shape, are connected with registration arm by the first locking screw; The lower end of outer bar is connected to side in the middle part of the sleeve of a hollow; Metal tubing one end is provided with the outside screw corresponding to guide pipe internal thread, and metal tubing is connected with guide pipe after sleeve, and metal tubing is fixed by sleeve by the 2nd locking screw; Measuring scale is one end is pointed metallic rod, metallic rod is provided with corresponding to location hook to the scale of distance between two tips, for measuring the distance in tunnel.

2. the tibial tunnel locating device based on personalized navigation template according to claim 1, it is characterised in that, the first described locking screw is arranged on the platform inside outer bar upper end, and the 2nd locking screw is arranged on the platform of lower cartridge.

3. the tibial tunnel locating device based on personalized navigation template according to claim 1, it is characterized in that, described pedestal wall thickness is 2��3mm, the nominal diameter of guide pipe internal thread is 4mm, and hollow sleeve internal diameter is 4mm, and length is 30mm, the externally threaded nominal diameter of metal tubing is 4mm, metal tubing internal diameter is 2mm, and wall thickness is 1mm, and measuring scale diameter is 3.4mm.