Holographic computing as a navigation system for humeral osteotomies

Holographic computing as a navigation system for humeral osteotomies | 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 Research Article Holographic computing as a navigation system for humeral osteotomies David Mayorga-Naranjo, Juan Gómez-Alessandri, Cristina Ramírez-Fuentes, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6770481/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 Purpose : Surgical navigation using holograms displayed via mixed reality glasses is already applied in orthopaedic procedures, particularly in shoulder and knee surgeries. Could this system be applied to long bone deformity correction? This study aims to employ this technology for the navigation of humeral osteotomies and evaluate its accuracy and reproducibility. Methods : A holographic software integrated with MRTK 2 (Microsoft, Redmond), USA was developed for Microsoft Hololens 2. Using 3D Builder, trackers were designed for mixed reality recognition, enabling spatial modification analysis. On fifteen humerus phantoms, an engineer performed navigated derotation osteotomies. Subsequently, a trainee and a pediatric orthopedic specialist each completed five osteotomies. CT scans measured the orientation achieved. The error, defined as the difference between planned and achieved orientation, was statistically analyzed for both manual and navigated techniques. Results : The average error of the navigated system was 1.73º (SD: 2.63), with statistically significant differences (p<0.05). In addition, the holographic computing system showed accuracy regardless of the osteotomy magnitude. In contrast, the freehand technique presented an average error of 14.2º (SD: 18.86) for the resident surgeon and 4.6º (SD: 17.56) for the specialist, with no statistically significant differences between them. The manual system presented lower precision and greater unpredictability compared to the navigated system. Conclusions : Surgical navigation based on holographic computing improves the accuracy of derotation osteotomy. Its accessibility and simplicity make it a promising technique for future surgical navigation systems. mixed reality glasses derotational osteotomy surgical navigation holographic computing Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction Derotational osteotomies of long bones are performed to reduce or eliminate pathological angulation in various bone conditions, particularly in pediatric cases. Notable examples include bone dysplasias or deformities secondary to fractures, such as cubitus varus resulting from a supracondylar humerus fracture. [ 1 , 2 ] Performing these osteotomies requires a thorough patient assessment and comprehensive evaluation, including various imaging studies. [ 1 ] From this study, preoperative planning can be carried out and the angulation that must be surgically corrected can be estimated, but currently there are no methods that accurately estimate the degrees of deformity and, therefore, the degrees that must be corrected intraoperatively. Among the techniques currently used by orthopedic surgeons to estimate this angulation are the placement of pins or the creation of marks on these long bones on either side of the planned osteotomy, representing the angulation to be corrected. [ 1 , 3 ] One drawback of these methods is that the surgeon's skill in visualizing the necessary angulation plays a crucial role in achieving an adequate correction. This introduces the possibility of varying outcomes depending on the surgeon performing the osteotomy, increasing the risk of secondary injuries or pathologies due to an altered post-surgical rotational profile. Osteotomy surgery has primarily focused on correcting lower limb deformities, with the development of customized guides that enhance precision and reproducibility.[ 4 , 5 ] However, these guides are associated with high costs, low versatility, and require days or even weeks of waiting from the time they are ordered until they become available for surgery. [ 3 ] An alternative could be surgical navigation based on mixed reality, which is already a reality, particularly in the field of knee and shoulder orthopedics. Advances in computing over the last decade have enabled the development of more compact and lightweight navigation systems based on mixed reality. This technology, which integrates virtual elements into the real world as holograms, allows surgeons to more easily and efficiently guide implant positioning or monitor intraoperative corrections. It has been successfully employed in shoulder and hip prosthetic surgeries, yielding excellent results and opening new horizons in intraoperative assistance systems for surgeons. This navigation system offers a cost-effective and logistically accessible structure, making it potentially viable for most hospitals worldwide. [ 6 ] But is this technology a real alternative in pediatric deformity correction surgery? Is it reliable and reproducible? The aim of this study is to evaluate the accuracy of performing humerus derotation osteotomies with a new navigation system based on holographic computerization. Material and methods Design and development of the holographic computing-based navigation system Currently, various software solutions exist for surgical planning based on 3D imaging techniques. These tools provide detailed anatomical information, highlight deformities, and even allow for the design of the required osteotomy.⁷ In our work, we use Microsoft HoloLens 2 mixed reality glasses, which consist of an "optical see-through head-mounted display" (OST-HMD). These glasses implement holographic computing software developed in C + + and integrated into MRTK 2 (Microsoft, Redmond, USA). MRTK is the SDK provided by Microsoft for developing applications for HoloLens ( https://docs.microsoft.com/windows/mixedreality/mrtk-unity/ ). MRTK can be integrated into the Unity ( https://unity.com ) or Unreal ( https://www.unrealengine.com ) engines, both of which support the same functionalities, including device/display tracking, hand input, and eye input, among others. This technology allows the surgeon to visualize their environment while overlaying holograms, which can be interacted with manually or through voice commands. The application can operate in any indoor setting and is customizable according to the surgeon's demands and needs. System recognition: positioner and trakcer Using the 3D Builder software (Microsoft Corporation®, Redmond, Washington, USA), which can be downloaded for free from the Windows Store, the design of two mirrored positioners is created. These positioners will house two trackers that are compatible with the image recognition system of HoloLens 2, allowing us to monitor spatial modifications occurring between the trackers. The design of the positioners is carried out by creating pieces with the planned sizes and shapes, which are then merged to establish the final design. The positioning device has a rectangular shape and allows the placement of three needles, which can be used to secure it to the piece we intend to osteotomize. There are two designs of the positioning device, a left and a right (Fig. 1 ), which are mirror images of each other. The positioning device is connected to allow visualization of the tracker on both sides of the osteotomy. These trackers are placed on both sides of the area where the osteotomy will be performed and will be recognized by the mixed-reality glasses, which will then establish the point where the osteotomy should be performed. Subsequently, the variation in degrees across the three spatial planes ("x," "y," "z") between the trackers will be indicated. Creation of the biomodels A humerus with standard dimensions was designed using the 3D Builder program (3D Builder, Microsoft Corporation® version 18.0.1931.0). The design was printed using additive manufacturing in polylactic acid (PLA) through Ender 3 Pro (Creality, Zangzhen, China). In total, 25 copies were printed, resulting in 25 identical biomodels. Study design The osteotomies were performed on these biomodels by an engineer, with no medical knowledge, and two surgeons, one in training and the other a pediatric orthopedics and traumatology consultant. For this, a series of target derotational osteotomies were defined following a consensus among the researchers. First, the engineer performed 15 osteotomies using the ARIS navigation system (VLN ST). Second, the surgeons each performed 5 osteotomies without the use of navigation, placing a Kirschner wire on each side of the area where the osteotomy would later be performed, and then applying the rotation that each surgeon considered to be the one previously determined as the target, without any type of guidance. Once the desired rotation was achieved, either through navigation or the manual technique, the two fragments of the biomodel were rejoined using pins and a plate or by fusing the polylactic acid through heat. Subsequently, a CT scan of the biomodels was performed (Fig. 2 ), and on these scans, two radiologists specialized in musculoskeletal radiology independently and blinded to the values previously defined by the surgeons, measured the rotation of the osteotomy performed on the biomodels, with an average calculated between these measurements. The angle of the achieved rotation is the result of the difference between the axis of the center of the humeral head and the transepicondylar axis of each of the osteotomized humerus (Fig. 3 ), compared to the angle between the center of the humeral head and the transepicondylar axis of a prototype humerus. Statistical method The statistical data were analyzed by an independent researcher using R-statistics version 3.5.2. The normality distribution of the data was assessed using the Shapiro-Wilk test. Additionally, the error was calculated as the difference between the planned and obtained orientation, both for the manual technique and the navigated technique. Ethical aspects This study was conducted in accordance with European recommendations for good clinical practice and the principles of the Declaration of Helsinki of the World Medical Association (WMA), revised in 2013, for clinical studies involving human participants. This study received approval from the ethics committee of our institution, with registration number 2025-0206-1. Results The measurements of the angle obtained in each osteotomy performed on the biomodels using the mixed-reality system were collected in the first table (Table 1 ). On the other hand, the measurements of the angle obtained in the osteotomies performed using the freehand technique by the resident surgeon (Table 2 ) and the specialist surgeon (Table 3 ) are presented in the second and third tables, respectively. The data followed a normal distribution as confirmed by the Shapiro-Wilk test (p = 0.12 for the mixed-reality system and p > 0.05 for the freehand system). The differences between the manual method and the navigated method were statistically significant (Fig. 4 ). The mean error in osteotomy angle using the mixed-reality system was 1.73º (SD: 2.63), with statistically significant differences (p = 0.02). In contrast, the manual technique resulted in mean error of 14.2º (SD: 18.86) for the resident surgeon and 4.6º (SD: 17.56) for the specialist in pediatric orthopedics, with no significant differences between the two (p > 0.05). With the navigated system, there was no increase in error over time (r squared − 0.01), thus demonstrating the stability of the system. Similarly, no greater error was observed with increasing magnitude (in degrees) of the osteotomy, with an r squared value of -0.03 (Fig. 5 A). Regarding the results obtained using the freehand technique, a larger error in the correction was observed as the magnitude of the correction increased (Fig. 5 B), with a tendency to undercorrect at higher values (r squared 0.27). Thus, mixed reality showed significantly better values in terms of precision, with statistically significant differences in precision between the techniques after applying the Bonferroni correction test between the mixed reality group and the freehand technique group performed by the specialist surgeon, as well as between the mixed reality group and the freehand technique group performed by the resident surgeon. Table 1 Mixed reality system: target angle and measurements of the obtained angle for each osteotomy performed. ATTEMPT (number) TARGET (degrees) RESULT (degrees) 1 14 16 2 32 33 3 13 14 4 40 42 5 46 45 6 19 26 7 16 15 8 14 14 9 14 12 10 20 23 11 29 29 12 40 41 13 19 26 14 8 11 15 20 23 Table 2 Freehand technique by resident surgeon: target angle and measurements of the obtained angle for each osteotomy performed. ATTEMPT (number) TARGET (degrees) RESULT (degrees) 1 14 51 2 32 40 3 13 34 4 40 26 5 46 65 Table 3 Freehand technique by specialist surgeon: target angle and measurements of the obtained angle for each osteotomy performed. ATTEMPT (number) TARGET (degrees) RESULT (degrees) 1 14 27 2 32 41 3 13 14 4 40 13 5 46 27 Discussion In recent years, mixed reality has emerged as a powerful new navigation system in orthopedic surgery. It has demonstrated the ability to provide greater precision, reproducibility, and safety in various fields, including shoulder and knee prosthetic surgery, where it allows for the real-time positioning of the different components of an arthroplasty. [ 8 – 11 ] In long bone deformity correction surgery, advancements in computed tomography and 3D software have led to the development of preoperative planning techniques and patient-specific osteotomy cutting guides. [ 7 , 12 ] However, there are currently no intraoperative navigation systems for osteotomies, [ 7 ] and regarding personalized guides, they are costly, require more extensive surgical dissection, and take longer to become available in the operating room. [ 4 , 5 , 12 ] This is where holographic computing can play a significant role. It is a new technology that has emerged in recent years, implemented through transparent or semi-transparent glasses that allow users to view holograms. These holograms can be interacted with using hand gestures or voice commands. This hardware is referred to as "OST-HMD," an acronym in English for "optical see-through head-mounted displays. [ 11 , 13 ] The hardware used in this system is commercially available from various brands, with notable examples including Microsoft HoloLens (Microsoft, Redmond, WA, USA), Google Glass (Google Inc., Mountain View, CA, USA), and Meta Quest (Meta Inc., Menlo Park, CA, USA). These glasses are versatile and feature an ergonomic design, capable of achieving millimetric precision in hardware with a relatively lightweight build of 566 grams. [ 8 ] This new navigation system operates within mixed reality, which should not be confused with virtual reality. While virtual reality provides users with an immersive experience in a digitally generated environment that replaces the real world, mixed reality integrates virtual elements into the real world, allowing for the coexistence and interaction of these elements. [ 7 , 8 , 13 ] In addition to real-time intraoperative navigation, mixed reality also offers other interesting applications in the correction of long bone deformities. These include performing accurate preoperative planning, providing practical training in surgical techniques for less experienced surgeons, and creating platforms for patient education. [ 7 , 13 , 14 ] In our study, we developed a navigation software based on holographic computing, implemented through mixed reality glasses marketed as Microsoft HoloLens 2. Through our study, we demonstrate that our new navigation system reduces the average error by approximately 90% in performing the osteotomy compared to the freehand technique performed by a resident surgeon, and by approximately 65% when the osteotomy is performed freehand by a specialist surgeon. Navigation using mixed reality does not exhibit greater errors based on usage time or the number of osteotomies performed, demonstrating system stability that ensures reproducibility in its application. In this way, holographic computerization demonstrates results comparable to those reported in other published articles to date regarding the use of this technology in other fields of orthopedics, such as shoulder prosthetic surgery. [ 8 – 11 ] The new navigation system presented in this study represents an advancement over current methods for performing osteotomies, offering greater precision and reproducibility compared to the freehand technique, while serving as a more versatile, cost-effective, and faster tool compared to specific cutting guides. In this way, the use of mixed reality as a navigation system for long bone osteotomies shows promising results, significantly improving reliability and technical precision, and can be seamlessly integrated into the logistical systems of virtually any hospital. However, although this type of technology demonstrates reliable results, we must ask whether the clinical outcomes will align with the high expectations it has generated. Currently, there are no clinical studies to confirm this, and it will likely take years to obtain significant results that can provide answers in these terms. Conclusions Holographic computer-assisted navigation in corrective surgery for long bone deformities improves the accuracy of osteotomy correction regardless of the level of medical training compared to conventional methods. Furthermore, due to its reproducibility, accessibility, and simplicity, it represents a more versatile and cost-effective alternative to current personalized cutting guides. In this way, it stands as a promising technique for bone deformity correction and the future of surgical navigation. Declarations Funding declaration: This work has not received any funding. Human ethics and consent to participate declarations: This study was conducted in accordance with European recommendations for good clinical practice and the principles of the Declaration of Helsinki of the World Medical Association (WMA), revised in 2013, for clinical studies involving human participants. This study received approval from the ethics committee of our institution, with registration number 2025-0206-1. Conflict of interest: The authors declare that they have no conflicts of interest related to the content of this article. Author Contribution All authors contributed to the study conception, design, material preparation, data collection and analysis. The first draft of the manuscript was written by David Mayorga Naranjo, and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. References Chaclas N, Dyer O, Mayers A, Wheatley B, Grandizio LC, Seeley M . Eye of the Carpenter: How Well do Orthopaedic Surgeons Estimate Angular Measurements in Derotational Osteotomies? J Pediatr Orthop. 2024 Feb 1;44(2):112-116. doi: 10.1097/BPO.0000000000002525. Epub 2023 Sep 26. PMID: 37750543. Calem DB, Lubiatowski P, Trenhaile S, Gobbato B, Wong I, Alkhateeb J, Erickson J . Mixed reality applications in upper extremity surgery: the future is now. EFORT Open Rev. 2024 Nov 8;9(11):1034-1046. doi: 10.1530/EOR-24-0080. PMID: 39513697; PMCID: PMC11619721. Ellsworth BK, Hoellwarth JS, Rozbruch SR . Percutaneous Femoral Derotational Osteotomy in the Skeletally Immature Patient. JBJS Essent Surg Tech. 2022 Sep 14:12(3):e22.00003. doi:10.2106/JBJS.ST.22.00003. PMID: 36816524; PMCID: PMC9931044. Zaffagnini S, Dal Fabbro G, Lucidi GA, Agostinone P, Belvedere C, Leardini A, Grassi A. Personalised opening wedge high tibial osteotomy with patient-specific plates and instrumentation accurately controls coronal correction and posterior slope: Results from a prospective first case series. Knee. 2023 Oct;44:89-99. doi: 10.1016/j.knee.2023.07.011. Epub 2023 Aug 8. PMID: 37562120. Aman ZS, DePhillipo NN, Peebles LA, Familiari F, LaPrade RF, Dekker TJ . Improved Accuracy of Coronal Alignment Can Be Attained Using 3D-Printed Patient-Specific Instrumentation for Knee Osteotomies: A Systematic Review of Level III and IV Studies. Arthroscopy. 2022 Sep;38(9):2741-2758. doi: 10.1016/j.arthro.2022.02.023. Epub 2022 Mar 2. PMID: 35247513. Ma S, Xiao L, Guo D, Shi Q, Shen R, Li X. Application of 3D-printed osteotomy guides in periacetabular osteotomy: A short-term clinical study. Int J Artif Organs. 2022 Nov;45/11):945-951. Doi: 10.1177/03913988221120026. Epub 2022 Aug 29. PMID: 36036079. Ferràs-Tarragó J, Sanchis-Alfonso V, Ramírez-Fuentes C, Roselló-Añón A, Alía-Martínez I . A 3D method to estimate the effect of derotational osteotomies over femoral maltorsion. Rev Esp Cir Ortop Traumatol. 2022 Nov-Dec: 66(6):454-460. English, Spanish. doi: 10.1016/j.recot.2022.01.006. Epub 2022 Mar 12. PMID: 35292212. Can Kolac U, Paksoy A, Akgün D. Three-dimensional planning, navigation, patient-specific instrumentation and mixed reality in shoulder arthroplasty: a digital orthopedic renaissance. EFORT Open Rev. 2024 Jun 3;9(6):517-527. doi: 10.1530/EOR-23-0200. PMID: 38828974; PMCID: PMC11195342. Kriechling P, Roner S, Liebmann F, Casari F, Fürnstahl P, Wieser K . Augmented reality for base plate component placement in reverse total shoulder arthroplasty: a feasibility study. Arch Orthop Trauma Surg. 2021 Sep;141(9):1447-1453. doi: 10.1007/s00402-020-03542-z. Epub 2020 Jul 26. PMID: 32715400; PMCID: PMC8354932. Rojas JT, Lädermann A, Ho SWL, Rashid MS, Zumstein MA . Glenoid Component Placement Assisted by Augmented Reality Through a Head-Mounted Display During Reverse Shoulder Arthroplasty. Arthrosc Tech. 2022 Apr 22;11(5):e863-e874. doi: 10.1016/j.eats.2021.12.046. PMID: 35646556; PMCID: PMC9134485.. Rojas JT, Menzemer J, Rashid MS, Hayoz A, Lädermann A, Zumstein MA . Navigated augmented reality through a head-mounted display leads to low deviation between planned, intra- and postoperative parameters during glenoid component placement of reverse shoulder arthroplasty: a proof-of-concept case series. J Shoulder Elbow Surg. 2024 Jun 26:S1058-2746(24)00453-1. doi: 10.1016/j.jse.2024.05.006. Epub ahead of print. PMID: 38942222. Wallace SJ, Patterson JT, Nork SE . Mathematically Directed Single-Cut Osteotomy. Medicina (Kaunas). 2022 Jul 21;58(7):971. doi: 10.3390/medicina58070971. PMID: 35888691; PMCID: PMC9323407. Lu L, Wang H, Liu P, Liu R, Zhang J, Xie Y, Liu S, Huo T, Xie M, Wu X, Ye Z . Applications of Mixed Reality Technology in Orthopedics Surgery: A Pilot Study. Front Bioeng Biotechnol. 2022 Feb 22;10:740507. doi: 10.3389/fbioe.2022.740507. PMID: 35273954; PMCID: PMC8902164. Longo UG, Lalli A, Gobbato B, Nazarian A . Metaverse, virtual reality and augmented reality in total shoulder arthroplasty: a systematic review. BMC Musculoskelet Disord. 2024 May 21;25(1):396. doi: 10.1186/s12891-024-07436-8. PMID: 38773483; PMCID: PMC11106997 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-6770481","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":466326122,"identity":"9296fde6-9b78-4b77-9b2b-d18119360b9f","order_by":0,"name":"David Mayorga-Naranjo","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBElEQVRIiWNgGAWjYDCCAwwGDAwGzDCuDRAzNh4gRUsaSEsDEVoY4FoOQwXxAL7bhzd+5imwjuafkXzs45ea83Zr2w8DbamxicalRfJcWrE0j0F67owbacmzZY7dTt52JhGo5VhabgMOLQZneAwkZxgczm24kWPMLMF2O9nsAFALY8NhfFqMf4K0zAdr+Xcu2ez8Q4JazCQ+ALVsAGph/Nh2wM7sBgFbJM+wlVl8APpl45lnycyMfckJZjeAtiTg8QvfGebNNxL+WOfOO558mPHHNzt7s/PpDx98qLHBqQUBBBIYmHkYGBLBKhMIKgcB/gMMjD8YGOyJUjwKRsEoGAUjCgAA1V9pkBGlREwAAAAASUVORK5CYII=","orcid":"","institution":"Hospital Universitari i Politècnic La Fe","correspondingAuthor":true,"prefix":"","firstName":"David","middleName":"","lastName":"Mayorga-Naranjo","suffix":""},{"id":466326123,"identity":"25806bcc-07b4-42f7-9c6f-3f68dda910a1","order_by":1,"name":"Juan Gómez-Alessandri","email":"","orcid":"","institution":"Hospital Universitari i Politècnic La Fe","correspondingAuthor":false,"prefix":"","firstName":"Juan","middleName":"","lastName":"Gómez-Alessandri","suffix":""},{"id":466326124,"identity":"98ee50e5-4d05-4478-8ae0-b21beb3c72ae","order_by":2,"name":"Cristina Ramírez-Fuentes","email":"","orcid":"","institution":"Hospital Universitari i Politècnic La Fe","correspondingAuthor":false,"prefix":"","firstName":"Cristina","middleName":"","lastName":"Ramírez-Fuentes","suffix":""},{"id":466326125,"identity":"54b0c99b-d53d-4fdf-b2a5-167ec5c2a06c","order_by":3,"name":"Marta Salom-Taverner","email":"","orcid":"","institution":"Hospital Universitari i Politècnic La Fe","correspondingAuthor":false,"prefix":"","firstName":"Marta","middleName":"","lastName":"Salom-Taverner","suffix":""},{"id":466326126,"identity":"902c7e19-ee41-4f1d-89c9-fca9edd6f3b4","order_by":4,"name":"Alfonso Valverde-Navarro","email":"","orcid":"","institution":"University of Valencia","correspondingAuthor":false,"prefix":"","firstName":"Alfonso","middleName":"","lastName":"Valverde-Navarro","suffix":""},{"id":466326127,"identity":"ec057946-610e-40b0-886e-9ef6b4ff0d81","order_by":5,"name":"Joan Ferràs-Tarragó","email":"","orcid":"","institution":"Vithas Valencia 9 de Octubre","correspondingAuthor":false,"prefix":"","firstName":"Joan","middleName":"","lastName":"Ferràs-Tarragó","suffix":""}],"badges":[],"createdAt":"2025-05-28 18:23:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6770481/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6770481/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":84214079,"identity":"397f1f28-62ad-4eaa-a370-eb21f63bc25f","added_by":"auto","created_at":"2025-06-09 10:25:16","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":76913,"visible":true,"origin":"","legend":"\u003cp\u003eImages from 3D Builder. Left (A) and right (B) positioning devices.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6770481/v1/5b40ccdbaf72bc007acdaa95.png"},{"id":84214081,"identity":"708081db-a8ba-4d2e-816b-104a3bf1165c","added_by":"auto","created_at":"2025-06-09 10:25:16","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":355615,"visible":true,"origin":"","legend":"\u003cp\u003eCT scan of the biomodels after the osteotomy procedure.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6770481/v1/a12b0f429d3befe36c5294ba.png"},{"id":84214780,"identity":"1bcff16f-a531-4dd2-b065-54602de017e3","added_by":"auto","created_at":"2025-06-09 10:33:16","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":115719,"visible":true,"origin":"","legend":"\u003cp\u003eAngle calculation. Left: center of the humeral head. Up right: transepicondylar axis. Bottom right: difference between them.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6770481/v1/9879dcfe04abf220064d2c85.png"},{"id":84214782,"identity":"96c89513-7330-4237-bd9a-aae64af5c52a","added_by":"auto","created_at":"2025-06-09 10:33:16","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":23983,"visible":true,"origin":"","legend":"\u003cp\u003eDifferences between the manual technique and the navigated technique.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-6770481/v1/87a67230ef61d0276bab6426.png"},{"id":84216237,"identity":"54d21321-6e66-4200-9d20-7e222e9b0ae8","added_by":"auto","created_at":"2025-06-09 10:41:16","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":62057,"visible":true,"origin":"","legend":"\u003cp\u003eError as error as a function of osteotomy magnitude (in degrees) in navigated system (A) and freehand technique (B).\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-6770481/v1/bca4ee33201591ee5a230b80.png"},{"id":85545728,"identity":"c61f8adb-128c-49e4-a734-2b051ffdb460","added_by":"auto","created_at":"2025-06-27 08:17:07","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1601219,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6770481/v1/8ba57393-4f6e-49c8-b2ef-e2f8d3dc56e4.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eHolographic computing as a navigation system for humeral osteotomies\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eDerotational osteotomies of long bones are performed to reduce or eliminate pathological angulation in various bone conditions, particularly in pediatric cases. Notable examples include bone dysplasias or deformities secondary to fractures, such as cubitus varus resulting from a supracondylar humerus fracture. [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e] Performing these osteotomies requires a thorough patient assessment and comprehensive evaluation, including various imaging studies. [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eFrom this study, preoperative planning can be carried out and the angulation that must be surgically corrected can be estimated, but currently there are no methods that accurately estimate the degrees of deformity and, therefore, the degrees that must be corrected intraoperatively.\u003c/p\u003e \u003cp\u003eAmong the techniques currently used by orthopedic surgeons to estimate this angulation are the placement of pins or the creation of marks on these long bones on either side of the planned osteotomy, representing the angulation to be corrected. [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] One drawback of these methods is that the surgeon's skill in visualizing the necessary angulation plays a crucial role in achieving an adequate correction. This introduces the possibility of varying outcomes depending on the surgeon performing the osteotomy, increasing the risk of secondary injuries or pathologies due to an altered post-surgical rotational profile.\u003c/p\u003e \u003cp\u003eOsteotomy surgery has primarily focused on correcting lower limb deformities, with the development of customized guides that enhance precision and reproducibility.[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] However, these guides are associated with high costs, low versatility, and require days or even weeks of waiting from the time they are ordered until they become available for surgery. [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eAn alternative could be surgical navigation based on mixed reality, which is already a reality, particularly in the field of knee and shoulder orthopedics.\u003c/p\u003e \u003cp\u003eAdvances in computing over the last decade have enabled the development of more compact and lightweight navigation systems based on mixed reality. This technology, which integrates virtual elements into the real world as holograms, allows surgeons to more easily and efficiently guide implant positioning or monitor intraoperative corrections. It has been successfully employed in shoulder and hip prosthetic surgeries, yielding excellent results and opening new horizons in intraoperative assistance systems for surgeons. This navigation system offers a cost-effective and logistically accessible structure, making it potentially viable for most hospitals worldwide. [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eBut is this technology a real alternative in pediatric deformity correction surgery? Is it reliable and reproducible? The aim of this study is to evaluate the accuracy of performing humerus derotation osteotomies with a new navigation system based on holographic computerization.\u003c/p\u003e"},{"header":"Material and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eDesign and development of the holographic computing-based navigation system\u003c/h2\u003e \u003cp\u003eCurrently, various software solutions exist for surgical planning based on 3D imaging techniques. These tools provide detailed anatomical information, highlight deformities, and even allow for the design of the required osteotomy.⁷\u003c/p\u003e \u003cp\u003eIn our work, we use Microsoft HoloLens 2 mixed reality glasses, which consist of an \"optical see-through head-mounted display\" (OST-HMD). These glasses implement holographic computing software developed in C\u0026thinsp;+\u0026thinsp;+\u0026thinsp;and integrated into MRTK 2 (Microsoft, Redmond, USA). MRTK is the SDK provided by Microsoft for developing applications for HoloLens (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://docs.microsoft.com/windows/mixedreality/mrtk-unity/\u003c/span\u003e\u003cspan address=\"https://docs.microsoft.com/windows/mixedreality/mrtk-unity/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e). MRTK can be integrated into the Unity (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://unity.com\u003c/span\u003e\u003cspan address=\"https://unity.com\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) or Unreal (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.unrealengine.com\u003c/span\u003e\u003cspan address=\"https://www.unrealengine.com\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e) engines, both of which support the same functionalities, including device/display tracking, hand input, and eye input, among others.\u003c/p\u003e \u003cp\u003eThis technology allows the surgeon to visualize their environment while overlaying holograms, which can be interacted with manually or through voice commands. The application can operate in any indoor setting and is customizable according to the surgeon's demands and needs.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eSystem recognition: positioner and trakcer\u003c/h3\u003e\n\u003cp\u003eUsing the 3D Builder software (Microsoft Corporation\u0026reg;, Redmond, Washington, USA), which can be downloaded for free from the Windows Store, the design of two mirrored positioners is created. These positioners will house two trackers that are compatible with the image recognition system of HoloLens 2, allowing us to monitor spatial modifications occurring between the trackers.\u003c/p\u003e \u003cp\u003eThe design of the positioners is carried out by creating pieces with the planned sizes and shapes, which are then merged to establish the final design.\u003c/p\u003e \u003cp\u003eThe positioning device has a rectangular shape and allows the placement of three needles, which can be used to secure it to the piece we intend to osteotomize. There are two designs of the positioning device, a left and a right (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e), which are mirror images of each other. The positioning device is connected to allow visualization of the tracker on both sides of the osteotomy.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThese trackers are placed on both sides of the area where the osteotomy will be performed and will be recognized by the mixed-reality glasses, which will then establish the point where the osteotomy should be performed. Subsequently, the variation in degrees across the three spatial planes (\"x,\" \"y,\" \"z\") between the trackers will be indicated.\u003c/p\u003e\n\u003ch3\u003eCreation of the biomodels\u003c/h3\u003e\n\u003cp\u003eA humerus with standard dimensions was designed using the 3D Builder program (3D Builder, Microsoft Corporation\u0026reg; version 18.0.1931.0). The design was printed using additive manufacturing in polylactic acid (PLA) through Ender 3 Pro (Creality, Zangzhen, China). In total, 25 copies were printed, resulting in 25 identical biomodels.\u003c/p\u003e\n\u003ch3\u003eStudy design\u003c/h3\u003e\n\u003cp\u003eThe osteotomies were performed on these biomodels by an engineer, with no medical knowledge, and two surgeons, one in training and the other a pediatric orthopedics and traumatology consultant.\u003c/p\u003e \u003cp\u003eFor this, a series of target derotational osteotomies were defined following a consensus among the researchers.\u003c/p\u003e \u003cp\u003eFirst, the engineer performed 15 osteotomies using the ARIS navigation system (VLN ST). Second, the surgeons each performed 5 osteotomies without the use of navigation, placing a Kirschner wire on each side of the area where the osteotomy would later be performed, and then applying the rotation that each surgeon considered to be the one previously determined as the target, without any type of guidance.\u003c/p\u003e \u003cp\u003eOnce the desired rotation was achieved, either through navigation or the manual technique, the two fragments of the biomodel were rejoined using pins and a plate or by fusing the polylactic acid through heat.\u003c/p\u003e \u003cp\u003eSubsequently, a CT scan of the biomodels was performed (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), and on these scans, two radiologists specialized in musculoskeletal radiology independently and blinded to the values previously defined by the surgeons, measured the rotation of the osteotomy performed on the biomodels, with an average calculated between these measurements.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe angle of the achieved rotation is the result of the difference between the axis of the center of the humeral head and the transepicondylar axis of each of the osteotomized humerus (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), compared to the angle between the center of the humeral head and the transepicondylar axis of a prototype humerus.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\n\u003ch3\u003eStatistical method\u003c/h3\u003e\n\u003cp\u003eThe statistical data were analyzed by an independent researcher using R-statistics version 3.5.2. The normality distribution of the data was assessed using the Shapiro-Wilk test.\u003c/p\u003e \u003cp\u003eAdditionally, the error was calculated as the difference between the planned and obtained orientation, both for the manual technique and the navigated technique.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eEthical aspects\u003c/h2\u003e \u003cp\u003e This study was conducted in accordance with European recommendations for good clinical practice and the principles of the Declaration of Helsinki of the World Medical Association (WMA), revised in 2013, for clinical studies involving human participants. This study received approval from the ethics committee of our institution, with registration number 2025-0206-1.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eThe measurements of the angle obtained in each osteotomy performed on the biomodels using the mixed-reality system were collected in the first table (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). On the other hand, the measurements of the angle obtained in the osteotomies performed using the freehand technique by the resident surgeon (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e) and the specialist surgeon (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) are presented in the second and third tables, respectively.\u003c/p\u003e \u003cp\u003eThe data followed a normal distribution as confirmed by the Shapiro-Wilk test (p\u0026thinsp;=\u0026thinsp;0.12 for the mixed-reality system and p\u0026thinsp;\u0026gt;\u0026thinsp;0.05 for the freehand system).\u003c/p\u003e \u003cp\u003eThe differences between the manual method and the navigated method were statistically significant (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). The mean error in osteotomy angle using the mixed-reality system was 1.73\u0026ordm; (SD: 2.63), with statistically significant differences (p\u0026thinsp;=\u0026thinsp;0.02). In contrast, the manual technique resulted in mean error of 14.2\u0026ordm; (SD: 18.86) for the resident surgeon and 4.6\u0026ordm; (SD: 17.56) for the specialist in pediatric orthopedics, with no significant differences between the two (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eWith the navigated system, there was no increase in error over time (r squared \u0026minus;\u0026thinsp;0.01), thus demonstrating the stability of the system.\u003c/p\u003e \u003cp\u003eSimilarly, no greater error was observed with increasing magnitude (in degrees) of the osteotomy, with an r squared value of -0.03 (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eA).\u003c/p\u003e \u003cp\u003eRegarding the results obtained using the freehand technique, a larger error in the correction was observed as the magnitude of the correction increased (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eB), with a tendency to undercorrect at higher values (r squared 0.27).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThus, mixed reality showed significantly better values in terms of precision, with statistically significant differences in precision between the techniques after applying the Bonferroni correction test between the mixed reality group and the freehand technique group performed by the specialist surgeon, as well as between the mixed reality group and the freehand technique group performed by the resident surgeon.\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 \u003cp\u003eMixed reality system: target angle and measurements of the obtained angle for each osteotomy performed.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eATTEMPT\u003c/p\u003e \u003cp\u003e(number)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTARGET\u003c/p\u003e \u003cp\u003e(degrees)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRESULT\u003c/p\u003e \u003cp\u003e(degrees)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e2\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e33\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e3\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e4\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e42\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e5\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e45\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e6\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e7\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e8\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e9\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e12\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e10\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e23\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e11\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e29\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e12\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e41\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e13\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e14\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e15\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e23\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eFreehand technique by resident surgeon: target angle and measurements of the obtained angle for each osteotomy performed.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eATTEMPT\u003c/p\u003e \u003cp\u003e(number)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTARGET\u003c/p\u003e \u003cp\u003e(degrees)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRESULT\u003c/p\u003e \u003cp\u003e(degrees)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e51\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e2\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e3\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e34\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e4\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e5\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e65\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eFreehand technique by specialist surgeon: target angle and measurements of the obtained angle for each osteotomy performed.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eATTEMPT\u003c/p\u003e \u003cp\u003e(number)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTARGET\u003c/p\u003e \u003cp\u003e(degrees)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRESULT\u003c/p\u003e \u003cp\u003e(degrees)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e27\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e2\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e41\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e3\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e4\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e5\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e27\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn recent years, mixed reality has emerged as a powerful new navigation system in orthopedic surgery. It has demonstrated the ability to provide greater precision, reproducibility, and safety in various fields, including shoulder and knee prosthetic surgery, where it allows for the real-time positioning of the different components of an arthroplasty. [\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eIn long bone deformity correction surgery, advancements in computed tomography and 3D software have led to the development of preoperative planning techniques and patient-specific osteotomy cutting guides. [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eHowever, there are currently no intraoperative navigation systems for osteotomies, [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] and regarding personalized guides, they are costly, require more extensive surgical dissection, and take longer to become available in the operating room. [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eThis is where holographic computing can play a significant role. It is a new technology that has emerged in recent years, implemented through transparent or semi-transparent glasses that allow users to view holograms. These holograms can be interacted with using hand gestures or voice commands. This hardware is referred to as \"OST-HMD,\" an acronym in English for \"optical see-through head-mounted displays. [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eThe hardware used in this system is commercially available from various brands, with notable examples including Microsoft HoloLens (Microsoft, Redmond, WA, USA), Google Glass (Google Inc., Mountain View, CA, USA), and Meta Quest (Meta Inc., Menlo Park, CA, USA). These glasses are versatile and feature an ergonomic design, capable of achieving millimetric precision in hardware with a relatively lightweight build of 566 grams. [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eThis new navigation system operates within mixed reality, which should not be confused with virtual reality. While virtual reality provides users with an immersive experience in a digitally generated environment that replaces the real world, mixed reality integrates virtual elements into the real world, allowing for the coexistence and interaction of these elements. [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eIn addition to real-time intraoperative navigation, mixed reality also offers other interesting applications in the correction of long bone deformities. These include performing accurate preoperative planning, providing practical training in surgical techniques for less experienced surgeons, and creating platforms for patient education. [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eIn our study, we developed a navigation software based on holographic computing, implemented through mixed reality glasses marketed as Microsoft HoloLens 2. Through our study, we demonstrate that our new navigation system reduces the average error by approximately 90% in performing the osteotomy compared to the freehand technique performed by a resident surgeon, and by approximately 65% when the osteotomy is performed freehand by a specialist surgeon.\u003c/p\u003e \u003cp\u003eNavigation using mixed reality does not exhibit greater errors based on usage time or the number of osteotomies performed, demonstrating system stability that ensures reproducibility in its application.\u003c/p\u003e \u003cp\u003eIn this way, holographic computerization demonstrates results comparable to those reported in other published articles to date regarding the use of this technology in other fields of orthopedics, such as shoulder prosthetic surgery. [\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eThe new navigation system presented in this study represents an advancement over current methods for performing osteotomies, offering greater precision and reproducibility compared to the freehand technique, while serving as a more versatile, cost-effective, and faster tool compared to specific cutting guides. In this way, the use of mixed reality as a navigation system for long bone osteotomies shows promising results, significantly improving reliability and technical precision, and can be seamlessly integrated into the logistical systems of virtually any hospital.\u003c/p\u003e \u003cp\u003eHowever, although this type of technology demonstrates reliable results, we must ask whether the clinical outcomes will align with the high expectations it has generated. Currently, there are no clinical studies to confirm this, and it will likely take years to obtain significant results that can provide answers in these terms.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eHolographic computer-assisted navigation in corrective surgery for long bone deformities improves the accuracy of osteotomy correction regardless of the level of medical training compared to conventional methods.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFurthermore, due to its reproducibility, accessibility, and simplicity, it represents a more versatile and cost-effective alternative to current personalized cutting guides. In this way, it stands as a promising technique for bone deformity correction and the future of surgical navigation.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding declaration:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work has not received any funding.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHuman ethics and consent to participate declarations:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was conducted in accordance with European recommendations for good clinical practice and the principles of the Declaration of Helsinki of the World Medical Association (WMA), revised in 2013, for clinical studies involving human participants. This study received approval from the ethics committee of our institution, with registration number 2025-0206-1.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no conflicts of interest related to the content of this article.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eAll authors contributed to the study conception, design, material preparation, data collection and analysis. The first draft of the manuscript was written by David Mayorga Naranjo, and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003e\u003cstrong\u003eChaclas N, Dyer O, Mayers A, Wheatley B, Grandizio LC, Seeley M\u003c/strong\u003e. Eye of the Carpenter: How Well do Orthopaedic Surgeons Estimate Angular Measurements in Derotational Osteotomies? J Pediatr Orthop. 2024 Feb 1;44(2):112-116. doi: 10.1097/BPO.0000000000002525. Epub 2023 Sep 26. PMID: 37750543.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eCalem DB, Lubiatowski P, Trenhaile S, Gobbato B, Wong I, Alkhateeb J, Erickson J\u003c/strong\u003e. Mixed reality applications in upper extremity surgery: the future is now. EFORT Open Rev. 2024 Nov 8;9(11):1034-1046. doi: 10.1530/EOR-24-0080. PMID: 39513697; PMCID: PMC11619721.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eEllsworth BK, Hoellwarth JS, Rozbruch SR\u003c/strong\u003e. Percutaneous Femoral Derotational Osteotomy in the Skeletally Immature Patient. JBJS Essent Surg Tech. 2022 Sep 14:12(3):e22.00003. doi:10.2106/JBJS.ST.22.00003. PMID: 36816524; PMCID: PMC9931044.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eZaffagnini S, Dal Fabbro G, Lucidi GA, Agostinone P, Belvedere C, Leardini A, Grassi A. \u003c/strong\u003ePersonalised opening wedge high tibial osteotomy with patient-specific plates and instrumentation accurately controls coronal correction and posterior slope: Results from a prospective first case series. Knee. 2023 Oct;44:89-99. doi: 10.1016/j.knee.2023.07.011. Epub 2023 Aug 8. PMID: 37562120.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eAman ZS, DePhillipo NN, Peebles LA, Familiari F, LaPrade RF, Dekker TJ\u003c/strong\u003e. Improved Accuracy of Coronal Alignment Can Be Attained Using 3D-Printed Patient-Specific Instrumentation for Knee Osteotomies: A Systematic Review of Level III and IV Studies. Arthroscopy. 2022 Sep;38(9):2741-2758. doi: 10.1016/j.arthro.2022.02.023. Epub 2022 Mar 2. PMID: 35247513.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eMa S, Xiao L, Guo D, Shi Q, Shen R, Li X. \u003c/strong\u003eApplication of 3D-printed osteotomy guides in periacetabular osteotomy: A short-term clinical study. Int J Artif Organs. 2022 Nov;45/11):945-951. Doi: 10.1177/03913988221120026. Epub 2022 Aug 29. PMID: 36036079.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eFerr\u0026agrave;s-Tarrag\u0026oacute; J, Sanchis-Alfonso V, Ram\u0026iacute;rez-Fuentes C, Rosell\u0026oacute;-A\u0026ntilde;\u0026oacute;n A, Al\u0026iacute;a-Mart\u0026iacute;nez I\u003c/strong\u003e. A 3D method to estimate the effect of derotational osteotomies over femoral maltorsion. Rev Esp Cir Ortop Traumatol. 2022 Nov-Dec: 66(6):454-460. English, Spanish. doi: 10.1016/j.recot.2022.01.006. Epub 2022 Mar 12. PMID: 35292212.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eCan Kolac U, Paksoy A, Akg\u0026uuml;n D. \u003c/strong\u003eThree-dimensional planning, navigation, patient-specific instrumentation and mixed reality in shoulder arthroplasty: a digital orthopedic renaissance. EFORT Open Rev. 2024 Jun 3;9(6):517-527. doi: 10.1530/EOR-23-0200. PMID: 38828974; PMCID: PMC11195342.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eKriechling P, Roner S, Liebmann F, Casari F, F\u0026uuml;rnstahl P, Wieser K\u003c/strong\u003e. Augmented reality for base plate component placement in reverse total shoulder arthroplasty: a feasibility study. Arch Orthop Trauma Surg. 2021 Sep;141(9):1447-1453. doi: 10.1007/s00402-020-03542-z. Epub 2020 Jul 26. PMID: 32715400; PMCID: PMC8354932.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eRojas JT, L\u0026auml;dermann A, Ho SWL, Rashid MS, Zumstein MA\u003c/strong\u003e. Glenoid Component Placement Assisted by Augmented Reality Through a Head-Mounted Display During Reverse Shoulder Arthroplasty. Arthrosc Tech. 2022 Apr 22;11(5):e863-e874. doi: 10.1016/j.eats.2021.12.046. PMID: 35646556; PMCID: PMC9134485..\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eRojas JT, Menzemer J, Rashid MS, Hayoz A, L\u0026auml;dermann A, Zumstein MA\u003c/strong\u003e. Navigated augmented reality through a head-mounted display leads to low deviation between planned, intra- and postoperative parameters during glenoid component placement of reverse shoulder arthroplasty: a proof-of-concept case series. J Shoulder Elbow Surg. 2024 Jun 26:S1058-2746(24)00453-1. doi: 10.1016/j.jse.2024.05.006. Epub ahead of print. PMID: 38942222.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eWallace SJ, Patterson JT, Nork SE\u003c/strong\u003e. Mathematically Directed Single-Cut Osteotomy. Medicina (Kaunas). 2022 Jul 21;58(7):971. doi: 10.3390/medicina58070971. PMID: 35888691; PMCID: PMC9323407.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eLu L, Wang H, Liu P, Liu R, Zhang J, Xie Y, Liu S, Huo T, Xie M, Wu X, Ye Z\u003c/strong\u003e. Applications of Mixed Reality Technology in Orthopedics Surgery: A Pilot Study. Front Bioeng Biotechnol. 2022 Feb 22;10:740507. doi: 10.3389/fbioe.2022.740507. PMID: 35273954; PMCID: PMC8902164.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eLongo UG, Lalli A, Gobbato B, Nazarian A\u003c/strong\u003e. Metaverse, virtual reality and augmented reality in total shoulder arthroplasty: a systematic review. BMC Musculoskelet Disord. 2024 May 21;25(1):396. doi: 10.1186/s12891-024-07436-8. PMID: 38773483; PMCID: PMC11106997\u003c/li\u003e\n\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":"mixed reality glasses, derotational osteotomy, surgical navigation, holographic computing","lastPublishedDoi":"10.21203/rs.3.rs-6770481/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6770481/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose\u003c/strong\u003e: Surgical navigation using holograms displayed via mixed reality glasses is already applied in orthopaedic procedures, particularly in shoulder and knee surgeries. Could this system be applied to long bone deformity correction? This study aims to employ this technology for the navigation of humeral osteotomies and evaluate its accuracy and reproducibility.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e: A holographic software integrated with MRTK 2 (Microsoft, Redmond), USA was developed for Microsoft Hololens 2. Using 3D Builder, trackers were designed for mixed reality recognition, enabling spatial modification analysis. On fifteen humerus phantoms, an engineer performed navigated derotation osteotomies. Subsequently, a trainee and a pediatric orthopedic specialist each completed five osteotomies. CT scans measured the orientation achieved. The error, defined as the difference between planned and achieved orientation, was statistically analyzed for both manual and navigated techniques.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e: The average error of the navigated system was 1.73º (SD: 2.63), with statistically significant differences (p\u0026lt;0.05). In addition, the holographic computing system showed accuracy regardless of the osteotomy magnitude. In contrast, the freehand technique presented an average error of 14.2º (SD: 18.86) for the resident surgeon and 4.6º (SD: 17.56) for the specialist, with no statistically significant differences between them. The manual system presented lower precision and greater unpredictability compared to the navigated system.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions\u003c/strong\u003e: Surgical navigation based on holographic computing improves the accuracy of derotation osteotomy. Its accessibility and simplicity make it a promising technique for future surgical navigation systems.\u003c/p\u003e","manuscriptTitle":"Holographic computing as a navigation system for humeral osteotomies","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-09 10:25:11","doi":"10.21203/rs.3.rs-6770481/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":"1ef20436-97e9-4757-88b6-f5996ff914d1","owner":[],"postedDate":"June 9th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-06-27T08:09:00+00:00","versionOfRecord":[],"versionCreatedAt":"2025-06-09 10:25:11","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6770481","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6770481","identity":"rs-6770481","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}