Preoperative measurement and analysis of femoral bone canals designed by 3D modelling in lateral extra-articular tenodesis

Preoperative measurement and analysis of femoral bone canals designed by 3D modelling in lateral extra-articular tenodesis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Preoperative measurement and analysis of femoral bone canals designed by 3D modelling in lateral extra-articular tenodesis Guangwen Yu, Xiaobing Xiang, Wengang Liu, Jianfa Chen, Yuanyuan Wang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3960100/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: The anterolateral ligament of the knee joint is an important structure for maintaining rotational stability. Lateral extra-articular tenodesis (LET) has attracted increasing attention. At present, this technique is a hot topic in the study of anterior cruciate ligament revision. Objective: Considering that the design of the LET bone canal is the key to successful surgery, a safe zone of the LET bone canal was created through computer-aided preoperative planning. Methods: Mimics 20.0 was used to conduct three-dimensional modelling of the femur and ACL bone canal. The LET bone canal before surgery was designed by Imageware 13.2. A safe zoom where the bone canal did not overlap with the ACL bone canal, trochlea of the femur, and anterior cartilage of the femoral lateral condyle was used, and the spatial relationship between the safe zoom and the femoral internal condyle was quantified. Results: In all 13 patients, the spherical surface did not overlap with the trochlea of the femur or the anterior cartilage of the lateral condyle of the femur. The sphere overlapped with the ACL canal in 13 patients. The safe zoom was the front of the internal condyle of the femur, and the closest distance from the zoom to the internal condyle of the femur was 9.4802±6.8796 mm. The distance from the medial condyle of the femur to the intersection formed by the line from the most anterior edge of the medial edge of the femoral condyle cartilage surface to the medial condyle and the safety plane was 14.2493±12.1392 mm. The distance from the medial condyle of the femur to the intersection formed by the line from the most inferior edge of the medial edge of the femoral condyle cartilage surface to the femoral condyle and the safety plane was 11.8494±8.7796 mm. In a single case, the shortest distance between the exit needle point and the interface of the safe area was 37.9224 mm. Conclusion: Computer-aided 3D modelling of the preoperative femoral bone canal design of LET can be used to quantify the spatial relationship between the exit needle points and the medial condyle of the femur, accurately plan the route of the LET bone canal, and effectively reduce the probability of LET canal and ACL bone canal overlap. Health sciences/Anatomy/Musculoskeletal system/Ligaments Health sciences/Anatomy/Musculoskeletal system/Tendons 3D modelling computer-assisted design femoral bone canal lateral extra-articular tenodesis Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Background The anterolateral ligament of the knee joint is an important structure for maintaining rotational stability. An increasing number of scholars have begun to pay attention to the importance of anterolateral structure reconstruction. Lemair[1] first reported the anterior lateral ligament of the knee joint. Currently, two different techniques are used for this anterolateral procedure: anatomic anterolateral ligament reconstruction (ALLR) [2] and nonanatomic modified Lemaire lateral extra-articular tenodesis (LET). [3-6] At present, comparisons of the efficacy of ALLR and LET have shown that both can maintain the stability of the knee joint, and the efficacy is similar without overconstraining the knee[7]. However, LET surgery is simpler than ALL surgery and does not require the use of a tibial tunnel, which can reduce the operation time. Therefore, LET surgery was selected as the method for preoperative bone canal design in this study. There have been many reports of LET surgery in the past five years. Most surgeons choose to use a 10 mm long fascia graft. In terms of fixation methods, there are currently two fixation methods: one is to use 7 mm interfacial screws after drilling a 6 mm bone canal from 8 mm behind the femoral lateral condyle to fix the tendon[8]. The second option is to choose suture anchor fixation[9]. Each has advantages and disadvantages. The first fixation method has very high requirements for the direction of the femoral bone canal. If the orientation of the bone canal is poorly selected and overlaps with that of the reconstructed bone canal of the anterior cruciate ligament, fixation of the anterior cruciate ligament and the LET will fail, resulting in failure of the operation. In this paper, the bone canal design for the fixation mode of anterolateral ligament tendons was discussed. In view of the serious consequences of overlapping bone canals, we used preoperative 3D modelling to reconstruct the bone tunnel of the original anterior cruciate ligament and design the direction and size of the LET bone canals. A safe zoom of the femoral bone canal was created by reverse engineering software, and the medial condyle of the femur was taken as a reference point for quantitative analysis. Methods and materials Patient selection: Thirteen patients who had completed standard single-bundle anterior cruciate ligament reconstruction. (Figure 1) Software application: Mimics 20.0: After the Dicom format of the knee was imported into the software, the image threshold was selected, local rendering (including the femur and anterior cruciate ligament bone canal) was performed, 3D modelling was automatically performed after rendering, and the STL format was exported. Imageware 13.2: The STL format of the femur and ACL bone canal was imported into the software to begin the design of the LET bone canal. The process of designing the LET bone canal 1. Determination of the insertion point of the LET: an axis centered on the femoral bone marrow cavity was generated, a plane on the coronal plane with the axis was drawn, and then a plane perpendicular to the coronal plane through the femoral lateral condyle was made. The insertion point was at the position where the plane intersects the lateral cortical surface of the femur and 8 cm behind the external condyle point. (Fig. 2) 2. The insertion point was considered the center of the circle, and a radius of 25+3 mm was used as a sphere to observe whether the sphere overlapped with the ACL bone tract, the trochlea of the femur, or the anterior cartilage of the lateral condyle of the femur. (Fig. 3) 3. The ACL canal was divided into coarse and fine bone canals (FIG. 4A), a cylinder of appropriate size was synthesized, and the radius of the cylinder was increased by 3 mm (the purpose was that the radius of the LET bone canal was 3 mm, and increasing the radius of the bone canal was equivalent to designing a safe route for the LET bone canal to avoid overlapping with the ACL bone canal after 6 mm drilling). (Fig. 4B) Figure 3A: Anteroposterior view of the femur and sphere; Figure 3B: The lateral view of the femur and the sphere, the sphere with a radius of 28 mm, and the spatial relationship with the femur and ACL bone canal showed that the sphere did not pass through the trochlea, intercondylar fossa, or the frontal cartilage surface of the femoral lateral condyle, suggesting that the LET bone canal was a safe area toward the trochlea and intercondylar fossa and would not hit the trochlea and lateral condyle cartilage surface. The posterior top of the sphere overlapped with the ACL bone canal and the inferior femur cartilage, suggesting that the insertion point to the rear was an unsafe area. 4. If the sphere did not overlap with the anterior cartilage surface of the trochlea or the lateral condyle of the femur, the safe area was considered to be in the direction of the trochlea and intercondylar fossa. (The angle of the bone canal should not be too small with respect to the lateral surface of the femoral lateral condyle; otherwise, the interfacial nail cannot be fixed in the femoral bone.) 5. Made the insertion point to the front tangent point of the coarse bone track and the thin bone track cylinder, and make two planes from the insertion point and the tangent point of the coarse bone track and the thin bone track, respectively, as the safety area boundary of LET. (Fig. 5) 6. Combined with the previous sphere area, the overall LET safety zoom (the area drawn by the red dot) was designed, and the final LET safety zoom was planned by combining with the Kirchner needle to minimize damage to the cartilage surface, considering that the needle point on the lateral bone surface of the femoral lateral condyle might cause the bone tunnel to break the bone cortex. (Dark red area) (Fig. 6) Case verification CT was performed after the LET operation, and 3D modelling was conducted after the DICOM format was derived, which overlapped with the 3D modelling before the LET operation (FIG. 7A), to observe the spatial relationship between the ACL bone canal and LET bone canal (FIG. 7B), as well as the needle entry and exit points of LET (FIG. 8). Results In all 13 patients, the spherical surface did not overlap with the trochlea of the femur or the anterior cartilage of the lateral condyle of the femur. The sphere overlapped with the ACL canal in 13 patients. The safe projection area was the front of the internal condyle of the femur, and the closest distance from the area to the internal condyle of the femur was 9.4802 ± 6.8796 mm. The distance from the medial condyle of the femur to the intersection formed by the line from the most anterior edge of the medial edge of the femoral condyle cartilage surface to the femoral condyle and the safety plane was 14.2493 ± 12.1392 mm. The distance from the medial condyle of the femur to the intersection formed by the line from the most inferior edge of the medial edge of the femoral condyle cartilage surface to the femoral condyle and the safety plane was 11.8494 ± 8.7796 mm. In a single case, the shortest distance between the needle point and the interface of the safe area was 37.9224 mm. (Table 1 ) Table 1 Patients Whether the fit sphere overlaps the trochlea of the femur and the anterior cartilage surface of the lateral condyle of the femur Whether the fit sphere overlaps with the ACL bone canal Minimum distance between the femoral condyle and the safety zone interface (mm) The distance from the medial condyle of the femur to the intersection which formed by the line form the most anterior edge of the medial edge of the femoral condyle cartilage surface to medial condyle of femur, and the safety plane The distance from the medial condyle of the femur to the intersection which formed by the line form the most inferior edge of the medial edge of the femoral condyle cartilage surface to medial condyle of femur, and the safety plane 1 N Y 10.8164 11.7974 12.2564 2 N Y 13.5616 18.0033 17.728 3 N Y 4.5359 5.7203 5.4186 4 N Y 16.891 38.3403 17.8318 5 N Y 11.4839 12.3974 12.4873 6 N Y 10.3143 12.6517 15.8379 7 N Y 8.8266 15.7246 10.7128 8 N Y 11.1656 21.4988 13.992 9 N Y 10.8968 12.0162 19.7073 10 N Y -2.9876 -3.8224 -3.0966 11 N Y 14.8112 20.2018 19.4567 12 N Y -4.8963 -7.4916 -7.857 13 N Y 17.8234 28.2028 19.5674 Note: Positive numbers indicate that the condyle of the femur was behind the safety zone interface, and negative numbers indicate that the condyle of the femur was in front of the safety zone interface. Discussion The reason for choosing the internal condyle of the femur as the reference point is that the internal condyle of the femur is a bone marker on the body surface and is easy to observe and detect. During the operation, only a 1 cm incision is required for the internal condyle of the knee joint to observe the relationship between the internal condyle and the exit point. For the placement of the bone canal, the ACL locator can be fixed on both sides of the preoperatively designed entry and exit points, and a 2.0 mm Kirschner needle can be temporarily preset in the bone during the operation to observe whether the entry and exit points at both ends of the Kirschner needle are consistent with the preoperative 3D plan. Why did we choose a 25 mm + 3 mm sphere? The length of the extrusion screw was 25 mm, and the radius of the extrusion screw was 3 mm. After taking these two aspects into account, we determined whether the formed LET bone canal overlapped with the ACL bone canal. Similarly, in this study, the radius of the ACL bone canal was increased by 3 mm after it was synthesized into a cylinder, as was the radius of the extrusion screws. The reason for choosing to increase the radius of the ACL bone canal instead of the radius of the LET bone canal was the convenience of the design and operation. If the bone canal radius of the LET was increased, the difficulty of the drawing operation would increase, which would not be convenient for routine operations in future cases. In most patients, the safe interface was in front of the femoral internal condyle, the needle point was relatively safe in front of the femoral internal condyle, and the LET bone canal did not easily overlap with the ACL bone canal. In 2 patients, the safety interface was found behind the internal condyle of the femur, which proved that if the needle point was found in the medial condyle of the femur, it might also be a safe area and not overlap with the ACL bone canal, possibly because of the influence of the size and direction of the ACL bone canal. Therefore, the safety route of the LET bone canal needs to be personalized according to the spatial position of the original bone canal of the ACL. The advantage of this method is that if the Kirchner needle is inserted accurately and the exit point is within the safe area, the orientation of the bone canal can be basically determined, the canal will not overlap with the ACL bone canal, and it will extend beyond the trochlea of the femur. Moreover, there is no need to verify whether the two bone canals overlap again under the supervision of arthroscopy, which saves operation time, and it is also not necessary to worry about the overlapping problem between the tunnel and the ACL tunnel after expanding the LET bone canals. The application of computer-aided 3D navigation in orthopedics, including knee replacement [ 10 , 11 ], osteotomy and orthosis of lower limb joints [ 12 ], evaluation of femoral and tibial bone canals after ACL reconstruction [ 13 – 16 ], anterior cruciate ligament bone canal navigation [ 17 , 18 ], and bone canal design during revision surgery [ 19 , 20 ], has been reported for many years. However, there are few reports in the literature on the bone canal design of LET. This paper aimed to use CAD technology for preoperative planning, measure the data automatically, improve the success rate of surgery, reduce the operation time, and obtain good surgical results. Conclusion Preoperative femoral bone canal design for LET through computer-aided 3D modelling can quantify the spatial relationship between needle points and the medial condyle of the femur, accurately plan the route of the LET bone canal, and effectively reduce the probability of LET bone canal and ACL bone canal overlap. Declarations Acknowledgements: Not applicable. Authors’ contributions: Guangwen Yu: Writing - original draft, Writing - review & editing. Xiaobing Xiang: Formal analysis, Data correction, Writing - review & editing. Wengang Liu: Writing - review & editing. Jianfa Chen: Writing - review & editing. Yuanyuan Wang: Writing - review & editing. Funding: This study was funded by the Guangdong Provincial Bureau of Traditional Chinese Medicine Research Project. (20241025) GuangDong Basic and Applied Basic Research Foundation. (2021A1515012564, 2023A1515012615) This study was approved by the Ethics Committee of Guangdong Second Traditional Chinese Medicine Hospital in accordance with the requirements for a retrospective review. Written informed consent was obtained from all subjects and their legal guardians for the publication of identifying information in an online open-access publication. All methods were performed in accordance with the relevant guidelines and regulations. Data availability All relevant data are within the paper, and the data are transparent. Consent for publication Not applicable. Competing interests The authors declare no competing interests. References Lemaire M. Ruptures anciennes du ligament croise anterieur du genou[J]. J Chir, 1967, 93(3): 311–320. Claes S, Vereecke E, Maes M, Victor J, Verdonk P, Bellemans J. Anatomy of the anterolateral ligament of the knee. J Anat. 2013;223(4):321–8. Sonnery-Cottet B, Barbosa NC, Tuteja S, Daggett M, Kajetanek C, Thaunat M. Minimally Invasive Anterolateral Ligament Reconstruction in the Setting of Anterior Cruciate Ligament Injury. Arthrosc Tech. 2016;5(1):e211-5. Wagner M, Weiler A. Anterolateral stabilization. Arthroskopie 2014;27:198–201 Chahla J, Menge TJ, Mitchell JJ, Dean CS, LaPrade RF. Anterolateral Ligament Reconstruction Technique: An Anatomic-Based Approach. Arthrosc Tech. 2016;5(3):e453-7. Lemaire M, Combelles F. Technique actuelle de plastie ligamentaire pour rupture ancienne du ligament croisé antérieur. Rev Chir Orthop 1980;66:523–525. Delaloye JR, Hartog C, Blatter S, Schläppi M, Müller D, Denzler D, Murar J, Koch PP. Anterolateral Ligament Reconstruction and Modified Lemaire Lateral Extra-Articular Tenodesis Similarly, Improve Knee Stability After Anterior Cruciate Ligament Reconstruction: A Biomechanical Study. Arthroscopy. 2020;36(7):1942–1950. Wasdev A, P A, Krishnan R, Thomas A, G SM, Amaravathi RS. 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Peak stresses shift from femoral tunnel aperture to tibial tunnel aperture in lateral tibial tunnel ACL reconstructions: a 3D graft-bending angle measurement and finite-element analysis. Knee Surg Sports Traumatol Arthrosc. 2018;26(2):508–517. Figueroa F, Figueroa D, Guiloff R, Putnis S, Fritsch B, Itriago M. Navigation in anterior cruciate ligament reconstruction: State of the art. J ISAKOS. 2023;8(1):47–53. Foo WYX, Chou ACC, Lie HM, Lie DTT. Computer-assisted navigation in ACL reconstruction improves anatomic tunnel placement with similar clinical outcomes. Knee. 2022;38:132–140. Plaweski S, Schlatterer B, Saragaglia D; Computer Assisted Orthopedic Surgery - France (CAOS - France). The role of computer assisted navigation in revision surgery for failed anterior cruciate ligament reconstruction of the knee: A continuous series of 52 cases. Orthop Traumatol Surg Res. 2015;101(6 Suppl):S227-31. Osti L, Buda M, Osti R, Massari L, Maffulli N. Preoperative Planning for ACL Revision Surgery. Sports Med Arthrosc Rev. 2017;25(1):19–29. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3960100","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":276338986,"identity":"e580cd74-99d7-457f-8a23-6d3bbe4a8b67","order_by":0,"name":"Guangwen Yu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAuUlEQVRIiWNgGAWjYBACAxDB+Memvp+Z+fADErQ0pDHObGdLMyBFy2HGDed5FCSI0mIukZ34uXAHM7PxYR6g/hqbaIJaLGfkbpaeeYaNzeww74EHDMfSchsIOuxG7gZpHjYeHrPDfAkGQBcSpWXzbx42CQnjZh4DCWK1bJPmbTMwMGAmWsuZt9usec4kJEgcBgZyAlF+OZ67+TZPxf8E/v7Dhx98qLEhrAUVJJCmfBSMglEwCkYBLgAAoac93m5QnuIAAAAASUVORK5CYII=","orcid":"","institution":"The Fifth Clinical College of Guangzhou University of Chinese Medicine","correspondingAuthor":true,"prefix":"","firstName":"Guangwen","middleName":"","lastName":"Yu","suffix":""},{"id":276338987,"identity":"ae292995-93aa-4160-b587-8f517d7bbbd4","order_by":1,"name":"Xiaobing Xiang","email":"","orcid":"","institution":"Guangzhou University of Traditional Chinese Medicine First Affiliated Hospital","correspondingAuthor":false,"prefix":"","firstName":"Xiaobing","middleName":"","lastName":"Xiang","suffix":""},{"id":276338989,"identity":"8b1c4e45-a922-422f-93ba-cbf456767efe","order_by":2,"name":"Wengang Liu","email":"","orcid":"","institution":"Guangdong Second Traditional Chinese Medicine Hospital","correspondingAuthor":false,"prefix":"","firstName":"Wengang","middleName":"","lastName":"Liu","suffix":""},{"id":276338990,"identity":"53fa2247-84b5-460e-ab4f-1f93c30dc65f","order_by":3,"name":"Jianfa Chen","email":"","orcid":"","institution":"Guangzhou University of Traditional Chinese Medicine First Affiliated Hospital","correspondingAuthor":false,"prefix":"","firstName":"Jianfa","middleName":"","lastName":"Chen","suffix":""},{"id":276338992,"identity":"9253e9f8-e0ed-400a-9d00-bd9e8f4e49a2","order_by":4,"name":"Yuanyuan Wang","email":"","orcid":"","institution":"Guangzhou University of Traditional Chinese Medicine First Affiliated Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yuanyuan","middleName":"","lastName":"Wang","suffix":""}],"badges":[],"createdAt":"2024-02-16 02:18:50","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3960100/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3960100/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":52034094,"identity":"4bc8f84f-91bd-4245-ab12-ec0ca21919b6","added_by":"auto","created_at":"2024-03-05 16:44:28","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":78863,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003e3D modelling of standard single-bundle anterior cruciate ligament reconstruction (the yellow area is the fine bone canal, and the purple area is the coarse bone canal).\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-3960100/v1/b70183e6032b61e9d7ef049b.png"},{"id":52034096,"identity":"c20e5fc6-19fb-453c-ab8e-2d4e7eccc281","added_by":"auto","created_at":"2024-03-05 16:44:28","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":185488,"visible":true,"origin":"","legend":"\u003cp\u003eDetermination of the insertion point (the lateral condyle of the femur 8 mm behind the horizontal level)\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-3960100/v1/5a74cb1f580026ffa9a949fc.png"},{"id":52034095,"identity":"8f6b6468-393f-4a62-b3f7-fcc60f2bb286","added_by":"auto","created_at":"2024-03-05 16:44:28","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":123010,"visible":true,"origin":"","legend":"\u003cp\u003e3A: Anteroposterior view of the femur and sphere; 3B: The lateral view of the femur and the sphere, the sphere with a radius of 28 mm, and the spatial relationship with the femur and ACL bone canal showed that the sphere did not pass through the trochlea, intercondylar fossa, or the frontal cartilage surface of the femoral lateral condyle, suggesting that the LET bone canal was a safe area toward the trochlea and intercondylar fossa and would not hit the trochlea and lateral condyle cartilage surface. The posterior top of the sphere overlapped with the ACL bone canal and the inferior femur cartilage, suggesting that the insertion point to the rear was an unsafe area.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-3960100/v1/9a738847186b887c7e873289.png"},{"id":52034093,"identity":"4148090d-dd57-49ad-9139-617b31f23aae","added_by":"auto","created_at":"2024-03-05 16:44:28","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":131660,"visible":true,"origin":"","legend":"\u003cp\u003e4A: The coarse and fine bone canals were divided. 4B: The coarse and fine bone canals of the ACL were fitted to a cylinder to facilitate the simulation of canals 3 mm larger than the original bone canals.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-3960100/v1/ec3de12d5f79675943f8c607.png"},{"id":52034097,"identity":"a4f8af1e-a368-4d34-b865-35da05b6c22a","added_by":"auto","created_at":"2024-03-05 16:44:28","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":224631,"visible":true,"origin":"","legend":"\u003cp\u003eTwo interfaces were created by the insertion point and interphase points on the two bone canals, and the three-dimensional space between the two interfaces and the internal condyle of the femur is displayed.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-3960100/v1/35015ac0f76c9e9fe6472010.png"},{"id":52034970,"identity":"76900538-0dea-4b7c-80ad-12ac87425fbd","added_by":"auto","created_at":"2024-03-05 16:52:28","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":74336,"visible":true,"origin":"","legend":"\u003cp\u003eThe dark red area is the safe zoom for letting the needle point\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-3960100/v1/470b39418fc9d4cae8fd365c.png"},{"id":52034101,"identity":"c0c2c235-bb61-4c73-905b-67241628066b","added_by":"auto","created_at":"2024-03-05 16:44:28","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":560661,"visible":true,"origin":"","legend":"\u003cp\u003e7A: Overlapping alignment of two 3D reconstructed models before (green) and after (yellow) LET; 7B: Registered ACL (green) and LET (white) bone canals. The figure shows that the ACL and LET bone canals did not overlap, which proved that the exit points are in the safe area.\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-3960100/v1/c23280bf1cc859cf39b4e543.png"},{"id":52035648,"identity":"8581a025-2abb-4ebd-aa80-3542761bda82","added_by":"auto","created_at":"2024-03-05 17:00:28","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":499184,"visible":true,"origin":"","legend":"\u003cp\u003e8A: Entry point of LET (white point); 8B: Exit point of LET (white point)\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-3960100/v1/dba4b94235d273c3b587cf51.png"},{"id":52034098,"identity":"9e2c86ca-06c4-4725-b428-1632c6cc450e","added_by":"auto","created_at":"2024-03-05 16:44:28","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":324328,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003e9A:\u003c/strong\u003e The distance from the medial condyle of the femur to the intersection formed by the line from the most anterior edge of the medial edge of the femoral condyle cartilage surface to the medial condyle of the femur and the safety plane. \u003cstrong\u003e\u0026nbsp;9B:\u003c/strong\u003e The distance from the medial condyle of the femur to the intersection formed by the line from the most inferior edge of the medial edge of the femoral condyle cartilage surface to the medial condyle of the femur and the safety plane.\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-3960100/v1/90da12eb95998b81f6e00aab.png"},{"id":54686381,"identity":"ad5e1f03-bbaf-455c-a1da-b3b94f3af35b","added_by":"auto","created_at":"2024-04-15 09:09:37","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2886612,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3960100/v1/ca6918ce-0951-4509-9f8e-4b2157043113.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Preoperative measurement and analysis of femoral bone canals designed by 3D modelling in lateral extra-articular tenodesis","fulltext":[{"header":"Background","content":"\u003cp\u003eThe anterolateral ligament of the knee joint is an important structure for maintaining rotational stability. An increasing number of scholars have begun to pay attention to the importance of anterolateral structure reconstruction. Lemair[1] first reported the anterior lateral ligament of the knee joint. Currently, two different techniques are used for this anterolateral procedure: anatomic anterolateral ligament reconstruction (ALLR) [2] and nonanatomic modified Lemaire lateral extra-articular tenodesis (LET). [3-6]\u003c/p\u003e\n\u003cp\u003eAt present, comparisons of the efficacy of ALLR and LET have shown that both can maintain the stability of the knee joint, and the efficacy is similar without overconstraining the knee[7].\u0026nbsp;However, LET surgery is simpler than ALL surgery and does not require the use of a tibial tunnel, which can reduce the operation time. Therefore, LET surgery was selected as the method for preoperative bone canal design in this study.\u003c/p\u003e\n\u003cp\u003eThere have been many reports of LET surgery in the past five years. Most surgeons choose to use a 10 mm long fascia graft. In terms of fixation methods, there are currently two fixation methods: one is to use 7 mm interfacial screws after drilling a 6 mm bone canal from 8 mm behind the femoral lateral condyle\u0026nbsp;to fix the tendon[8]. The second option is to choose suture anchor fixation[9]. Each has advantages and disadvantages.\u0026nbsp;The first fixation method has very high requirements for the direction of the femoral bone canal. If the orientation of the bone canal is poorly selected and overlaps with that of the reconstructed bone canal of the anterior cruciate ligament, fixation of the anterior cruciate ligament and the LET will fail, resulting in failure of the operation.\u003c/p\u003e\n\u003cp\u003eIn this paper, the bone canal design for the fixation mode of anterolateral ligament tendons was discussed. In view of the serious consequences of overlapping bone canals, we used preoperative 3D modelling to reconstruct the bone tunnel of the original anterior cruciate ligament and design the direction and size of the LET bone canals. A safe zoom of the femoral bone canal was created by reverse engineering software, and the medial condyle of the femur was taken as a reference point for quantitative analysis.\u003c/p\u003e"},{"header":"Methods and materials","content":"\u003cp\u003ePatient selection: Thirteen patients who had completed standard single-bundle anterior cruciate ligament reconstruction. (Figure 1)\u003c/p\u003e\n\u003cp\u003eSoftware application:\u003c/p\u003e\n\u003cp\u003eMimics 20.0: After the Dicom format of the knee was imported into the software, the image threshold was selected, local rendering (including the femur and anterior cruciate ligament bone canal) was performed, 3D modelling was automatically performed after rendering, and the STL format was exported.\u003c/p\u003e\n\u003cp\u003eImageware 13.2: The STL format of the femur and ACL bone canal was imported into the software to begin the design of the LET bone canal.\u003c/p\u003e\n\u003cp\u003eThe process of designing the LET bone canal\u003c/p\u003e\n\u003cp\u003e1. Determination of the insertion point of the LET: an axis centered on the femoral bone marrow cavity was generated, a plane on the coronal plane with the axis was drawn, and then a plane perpendicular to the coronal plane through the femoral lateral condyle was made. The insertion point was at the position where the plane intersects the lateral cortical surface of the femur and 8 cm behind the external condyle point. (Fig. 2)\u003c/p\u003e\n\u003cp\u003e2. The insertion point was considered the center of the circle, and a radius of 25+3 mm was used as a sphere to observe whether the sphere overlapped with the ACL bone tract, the trochlea of the femur, or the anterior cartilage of the lateral condyle of the femur. (Fig. 3)\u003c/p\u003e\n\u003cp\u003e3. The ACL canal was divided into coarse and fine bone canals (FIG. 4A), a cylinder of appropriate size was synthesized, and the radius of the cylinder was increased by 3 mm (the purpose was that the radius of the LET bone canal was 3 mm, and increasing the radius of the bone canal was equivalent to designing a safe route for the LET bone canal to avoid overlapping with the ACL bone canal after 6 mm drilling). (Fig. 4B)\u003c/p\u003e\n\u003cp\u003eFigure 3A: Anteroposterior view of the femur and sphere; Figure 3B: The lateral view of the femur and the sphere, the sphere with a radius of 28 mm, and the spatial relationship with the femur and ACL bone canal showed that the sphere did not pass through the trochlea, intercondylar fossa, or the frontal cartilage surface of the femoral lateral condyle, suggesting that the LET bone canal was a safe area toward the trochlea and intercondylar fossa and would not hit the trochlea and lateral condyle cartilage surface. The posterior top of the sphere overlapped with the ACL bone canal and the inferior femur cartilage, suggesting that the insertion point to the rear was an unsafe area.\u003c/p\u003e\n\u003cp\u003e4. If the sphere did not overlap with the anterior cartilage surface of the trochlea or the lateral condyle of the femur, the safe area was considered to be in the direction of the trochlea and intercondylar fossa. (The angle of the bone canal should not be too small with respect to the lateral surface of the femoral lateral condyle; otherwise, the interfacial nail cannot be fixed in the femoral bone.)\u003c/p\u003e\n\u003cp\u003e5. Made the insertion point to the front tangent point of the coarse bone track and the thin bone track cylinder, and make two planes from the insertion point and the tangent point of the coarse bone track and the thin bone track, respectively, as the safety area boundary of LET. (Fig. 5)\u003c/p\u003e\n\u003cp\u003e6. Combined with the previous sphere area, the overall LET safety zoom (the area drawn by the red dot) was designed, and the final LET safety zoom was planned by combining with the Kirchner needle to minimize damage to the cartilage surface, considering that the needle point on the lateral bone surface of the femoral lateral condyle might cause the bone tunnel to break the bone cortex. (Dark red area) (Fig. 6)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCase verification\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCT was performed after the LET operation, and 3D modelling was conducted after the DICOM format was derived, which overlapped with the 3D modelling before the LET operation (FIG. 7A), to observe the spatial relationship between the ACL bone canal and LET bone canal (FIG. 7B), as well as the needle entry and exit points of LET (FIG. 8).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eIn all 13 patients, the spherical surface did not overlap with the trochlea of the femur or the anterior cartilage of the lateral condyle of the femur. The sphere overlapped with the ACL canal in 13 patients. The safe projection area was the front of the internal condyle of the femur, and the closest distance from the area to the internal condyle of the femur was 9.4802\u0026thinsp;\u0026plusmn;\u0026thinsp;6.8796 mm. The distance from the medial condyle of the femur to the intersection formed by the line from the most anterior edge of the medial edge of the femoral condyle cartilage surface to the femoral condyle and the safety plane was 14.2493\u0026thinsp;\u0026plusmn;\u0026thinsp;12.1392 mm. The distance from the medial condyle of the femur to the intersection formed by the line from the most inferior edge of the medial edge of the femoral condyle cartilage surface to the femoral condyle and the safety plane was 11.8494\u0026thinsp;\u0026plusmn;\u0026thinsp;8.7796 mm. In a single case, the shortest distance between the needle point and the interface of the safe area was 37.9224 mm. (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e\u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePatients\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWhether the fit sphere overlaps the trochlea of the femur and the anterior cartilage surface of the lateral condyle of the femur\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eWhether the fit sphere overlaps with the ACL bone canal\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMinimum distance between the femoral condyle and the safety zone interface (mm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eThe distance from the medial condyle of the femur to the intersection which formed by the line form the most anterior edge of the medial edge of the femoral condyle cartilage surface to medial condyle of femur, and the safety plane\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eThe distance from the medial condyle of the femur to the intersection which formed by the line form the most inferior edge of the medial edge of the femoral condyle cartilage surface to medial condyle of femur, and the safety plane\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e10.8164\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e11.7974\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e12.2564\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e13.5616\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e18.0033\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e17.728\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e4.5359\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e5.7203\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e5.4186\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e16.891\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e38.3403\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e17.8318\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e11.4839\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e12.3974\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e12.4873\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e10.3143\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e12.6517\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e15.8379\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e8.8266\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e15.7246\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e10.7128\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e11.1656\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e21.4988\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e13.992\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e10.8968\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e12.0162\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e19.7073\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e-2.9876\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-3.8224\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e-3.0966\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e14.8112\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e20.2018\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e19.4567\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e-4.8963\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e-7.4916\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e-7.857\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eY\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e17.8234\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e28.2028\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e19.5674\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003eNote: Positive numbers indicate that the condyle of the femur was behind the safety zone interface, and negative numbers indicate that the condyle of the femur was in front of the safety zone interface.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe reason for choosing the internal condyle of the femur as the reference point is that the internal condyle of the femur is a bone marker on the body surface and is easy to observe and detect. During the operation, only a 1 cm incision is required for the internal condyle of the knee joint to observe the relationship between the internal condyle and the exit point. For the placement of the bone canal, the ACL locator can be fixed on both sides of the preoperatively designed entry and exit points, and a 2.0 mm Kirschner needle can be temporarily preset in the bone during the operation to observe whether the entry and exit points at both ends of the Kirschner needle are consistent with the preoperative 3D plan.\u003c/p\u003e \u003cp\u003eWhy did we choose a 25 mm\u0026thinsp;+\u0026thinsp;3 mm sphere? The length of the extrusion screw was 25 mm, and the radius of the extrusion screw was 3 mm. After taking these two aspects into account, we determined whether the formed LET bone canal overlapped with the ACL bone canal. Similarly, in this study, the radius of the ACL bone canal was increased by 3 mm after it was synthesized into a cylinder, as was the radius of the extrusion screws. The reason for choosing to increase the radius of the ACL bone canal instead of the radius of the LET bone canal was the convenience of the design and operation. If the bone canal radius of the LET was increased, the difficulty of the drawing operation would increase, which would not be convenient for routine operations in future cases.\u003c/p\u003e \u003cp\u003eIn most patients, the safe interface was in front of the femoral internal condyle, the needle point was relatively safe in front of the femoral internal condyle, and the LET bone canal did not easily overlap with the ACL bone canal. In 2 patients, the safety interface was found behind the internal condyle of the femur, which proved that if the needle point was found in the medial condyle of the femur, it might also be a safe area and not overlap with the ACL bone canal, possibly because of the influence of the size and direction of the ACL bone canal. Therefore, the safety route of the LET bone canal needs to be personalized according to the spatial position of the original bone canal of the ACL.\u003c/p\u003e \u003cp\u003eThe advantage of this method is that if the Kirchner needle is inserted accurately and the exit point is within the safe area, the orientation of the bone canal can be basically determined, the canal will not overlap with the ACL bone canal, and it will extend beyond the trochlea of the femur. Moreover, there is no need to verify whether the two bone canals overlap again under the supervision of arthroscopy, which saves operation time, and it is also not necessary to worry about the overlapping problem between the tunnel and the ACL tunnel after expanding the LET bone canals.\u003c/p\u003e \u003cp\u003eThe application of computer-aided 3D navigation in orthopedics, including knee replacement [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e], osteotomy and orthosis of lower limb joints [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], evaluation of femoral and tibial bone canals after ACL reconstruction [\u003cspan additionalcitationids=\"CR14 CR15\" citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e], anterior cruciate ligament bone canal navigation [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e], and bone canal design during revision surgery [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], has been reported for many years. However, there are few reports in the literature on the bone canal design of LET. This paper aimed to use CAD technology for preoperative planning, measure the data automatically, improve the success rate of surgery, reduce the operation time, and obtain good surgical results.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003ePreoperative femoral bone canal design for LET through computer-aided 3D modelling can quantify the spatial relationship between needle points and the medial condyle of the femur, accurately plan the route of the LET bone canal, and effectively reduce the probability of LET bone canal and ACL bone canal overlap.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eAcknowledgements: Not applicable.\u003c/p\u003e\n\u003cp\u003eAuthors\u0026rsquo; contributions: Guangwen Yu: Writing - original draft, Writing - review \u0026amp; editing.\u0026nbsp;Xiaobing Xiang: Formal analysis, Data correction, Writing - review \u0026amp; editing.\u0026nbsp;Wengang Liu: Writing - review \u0026amp; editing.\u0026nbsp;Jianfa Chen: Writing - review \u0026amp; editing.\u0026nbsp;Yuanyuan Wang: Writing - review \u0026amp; editing.\u003c/p\u003e\n\u003cp\u003eFunding: This study was funded by the Guangdong Provincial Bureau of Traditional Chinese Medicine Research Project. (20241025) GuangDong\u0026nbsp;Basic\u0026nbsp;and\u0026nbsp;Applied\u0026nbsp;Basic\u0026nbsp;Research\u0026nbsp;Foundation. (2021A1515012564, 2023A1515012615)\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethics Committee of Guangdong Second Traditional Chinese Medicine Hospital in accordance with the requirements for a retrospective review. Written informed consent was obtained from all subjects and their legal guardians for the publication of identifying information in an online open-access publication. All methods were performed in accordance with the relevant guidelines and regulations.\u003c/p\u003e\n\u003cp\u003eData availability\u003c/p\u003e\n\u003cp\u003eAll relevant data are within the paper, and the data are transparent.\u003c/p\u003e\n\u003cp\u003eConsent for publication Not applicable.\u003c/p\u003e\n\u003cp\u003eCompeting interests The authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eLemaire M. Ruptures anciennes du ligament croise anterieur du genou[J]. J Chir, 1967, 93(3): 311\u0026ndash;320.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eClaes S, Vereecke E, Maes M, Victor J, Verdonk P, Bellemans J. Anatomy of the anterolateral ligament of the knee. J Anat. 2013;223(4):321\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSonnery-Cottet B, Barbosa NC, Tuteja S, Daggett M, Kajetanek C, Thaunat M. Minimally Invasive Anterolateral Ligament Reconstruction in the Setting of Anterior Cruciate Ligament Injury. Arthrosc Tech. 2016;5(1):e211-5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWagner M, Weiler A. Anterolateral stabilization. Arthroskopie 2014;27:198\u0026ndash;201\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChahla J, Menge TJ, Mitchell JJ, Dean CS, LaPrade RF. Anterolateral Ligament Reconstruction Technique: An Anatomic-Based Approach. Arthrosc Tech. 2016;5(3):e453-7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLemaire M, Combelles F. Technique actuelle de plastie ligamentaire pour rupture ancienne du ligament crois\u0026eacute; ant\u0026eacute;rieur. Rev Chir Orthop 1980;66:523\u0026ndash;525.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDelaloye JR, Hartog C, Blatter S, Schl\u0026auml;ppi M, M\u0026uuml;ller D, Denzler D, Murar J, Koch PP. Anterolateral Ligament Reconstruction and Modified Lemaire Lateral Extra-Articular Tenodesis Similarly, Improve Knee Stability After Anterior Cruciate Ligament Reconstruction: A Biomechanical Study. Arthroscopy. 2020;36(7):1942\u0026ndash;1950.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWasdev A, P A, Krishnan R, Thomas A, G SM, Amaravathi RS. Anatomical Landmark Technique for Femoral Tunnel Placement of Lateral Extra-Articular Tenodesis. Arthrosc Tech. 2023;12(5):e779-e786.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eXu J, Qiao Y, Han K, Xu C, Dong S, Zhao J. Modified Lemaire Lateral Extra-articular Tenodesis With the Iliotibial Band Strip Fixed on the Femoral Cortical Surface Reduces Laxity and Causes Less Overconstraint in the Anterolateral Lesioned Knee: A Biomechanical Study. Arthroscopy. 2022;38(12):3162\u0026ndash;3171.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJones CW, Jerabek SA. Current Role of Computer Navigation in Total Knee Arthroplasty. J Arthroplasty. 2018;33(7):1989\u0026ndash;1993.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHannan R, Free M, Arora V, Harle R, Harvie P. Accuracy of computer navigation in total knee arthroplasty: A prospective computed tomography-based study. Med Eng Phys. 2020;79:52\u0026ndash;59.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChang J, Scallon G, Beckert M, Zavala J, Bollier M, Wolf B, Albright J. Comparing the accuracy of high tibial osteotomies between computer navigation and conventional methods. Comput Assist Surg (Abingdon). 2017;22(1):1\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eReynaud O, Batailler C, Lording T, Lustig S, Servien E, Neyret P. Three dimensionalCT analysis of femoral tunnel position after ACL reconstruction. A prospective study of one hundred and thirty five cases. Int Orthop. 2017;41(11):2313\u0026ndash;2319.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKim MS, Koh IJ, Sohn S, Kang BM, Jung H, In Y. Femoral offset guide facilitates accurate and precise femoral tunnel placement for single-bundle anterior cruciate ligament reconstruction. Knee Surg Sports Traumatol Arthrosc. 2019;27(11):3505\u0026ndash;3512.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eReynaud O, Batailler C, Lording T, Lustig S, Servien E, Neyret P. Three dimensionalCT analysis of femoral tunnel position after ACL reconstruction. A prospective study of one hundred and thirty five cases. Int Orthop. 2017;41(11):2313\u0026ndash;2319.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVan Der Bracht H, Tampere T, Beekman P, Schepens A, Devriendt W, Cromheecke M, Verdonk P, Victor J. Peak stresses shift from femoral tunnel aperture to tibial tunnel aperture in lateral tibial tunnel ACL reconstructions: a 3D graft-bending angle measurement and finite-element analysis. Knee Surg Sports Traumatol Arthrosc. 2018;26(2):508\u0026ndash;517.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFigueroa F, Figueroa D, Guiloff R, Putnis S, Fritsch B, Itriago M. Navigation in anterior cruciate ligament reconstruction: State of the art. J ISAKOS. 2023;8(1):47\u0026ndash;53.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFoo WYX, Chou ACC, Lie HM, Lie DTT. Computer-assisted navigation in ACL reconstruction improves anatomic tunnel placement with similar clinical outcomes. Knee. 2022;38:132\u0026ndash;140.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePlaweski S, Schlatterer B, Saragaglia D; Computer Assisted Orthopedic Surgery - France (CAOS - France). The role of computer assisted navigation in revision surgery for failed anterior cruciate ligament reconstruction of the knee: A continuous series of 52 cases. Orthop Traumatol Surg Res. 2015;101(6 Suppl):S227-31.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOsti L, Buda M, Osti R, Massari L, Maffulli N. Preoperative Planning for ACL Revision Surgery. Sports Med Arthrosc Rev. 2017;25(1):19\u0026ndash;29.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"3D modelling, computer-assisted design, femoral bone canal, lateral extra-articular tenodesis","lastPublishedDoi":"10.21203/rs.3.rs-3960100/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3960100/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBackground: The anterolateral ligament of the knee joint is an important structure for maintaining rotational stability. Lateral extra-articular tenodesis (LET) has attracted increasing attention. At present, this technique is a hot topic in the study of anterior cruciate ligament revision.\u003c/p\u003e\n\u003cp\u003eObjective: Considering that the design of the LET bone canal is the key to successful surgery, a safe zone of the LET bone canal was created through computer-aided preoperative planning.\u003c/p\u003e\n\u003cp\u003eMethods: Mimics 20.0 was used to conduct three-dimensional modelling of the femur and ACL bone canal. The LET bone canal before surgery was designed by Imageware 13.2. A safe zoom where the bone canal did not overlap with the ACL bone canal, trochlea of the femur, and anterior cartilage of the femoral lateral condyle was used, and the spatial relationship between the safe zoom and the femoral internal condyle was quantified.\u003c/p\u003e\n\u003cp\u003eResults: In all 13 patients, the spherical surface did not overlap with the trochlea of the femur or the anterior cartilage of the lateral condyle of the femur. The sphere overlapped with the ACL canal in 13 patients. The safe zoom was the front of the internal condyle of the femur, and the closest distance from the zoom to the internal condyle of the femur was 9.4802±6.8796 mm. The distance from the medial condyle of the femur to the intersection formed by the line from the most anterior edge of the medial edge of the femoral condyle cartilage surface to the medial condyle and the safety plane was 14.2493±12.1392 mm. The distance from the medial condyle of the femur to the intersection formed by the line from the most inferior edge of the medial edge of the femoral condyle cartilage surface to the femoral condyle and the safety plane was 11.8494±8.7796 mm. In a single case, the shortest distance between the exit needle point and the interface of the safe area was 37.9224 mm.\u003c/p\u003e\n\u003cp\u003eConclusion: Computer-aided 3D modelling of the preoperative femoral bone canal design of LET can be used to quantify the spatial relationship between the exit needle points and the medial condyle of the femur, accurately plan the route of the LET bone canal, and effectively reduce the probability of LET canal and ACL bone canal overlap.\u003c/p\u003e","manuscriptTitle":"Preoperative measurement and analysis of femoral bone canals designed by 3D modelling in lateral extra-articular tenodesis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-03-05 16:44:23","doi":"10.21203/rs.3.rs-3960100/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"f308b841-12e8-46ff-82d8-c50acbb3431b","owner":[],"postedDate":"March 5th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":29127020,"name":"Health sciences/Anatomy/Musculoskeletal system/Ligaments"},{"id":29127021,"name":"Health sciences/Anatomy/Musculoskeletal system/Tendons"}],"tags":[],"updatedAt":"2024-04-15T09:01:30+00:00","versionOfRecord":[],"versionCreatedAt":"2024-03-05 16:44:23","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3960100","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3960100","identity":"rs-3960100","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}