Clinical and Radiological Outcomes of Magnetically Controlled Intramedullary Lengthening Nails in Adolescents and Young Adults: A Retrospective Cohort Study

Clinical and Radiological Outcomes of Magnetically Controlled Intramedullary Lengthening Nails in Adolescents and Young Adults: A Retrospective Cohort Study | 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 Clinical and Radiological Outcomes of Magnetically Controlled Intramedullary Lengthening Nails in Adolescents and Young Adults: A Retrospective Cohort Study Mehmet Ali Talmaç, Melih Civan, Ergün Mendes This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6727984/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 16 Jun, 2025 Read the published version in Journal of Orthopaedic Surgery and Research → Version 1 posted 1 You are reading this latest preprint version Abstract Background: Magnetically controlled intramedullary lengthening nails offer a fully internal approach to limb lengthening, avoiding complications associated with external fixators such as pin site infections and soft tissue transfixation. While their use in adults is well-documented, evidence regarding their safety and efficacy in adolescents and young adults remains limited. Methods: This retrospective cohort study evaluated the clinical and radiological outcomes of 24 limb lengthening procedures performed in 18 adolescent and young adult patients between 2022 and 2024 using PRECICE® intramedullary lengthening nails. Patients aged ≤18 years with a minimum of 9 months follow-up were included. Lengthening parameters, regenerate morphology, complication rates, and inter-group comparisons were analyzed. Results: A total of 24 long bone segments (femur, tibia, and humerus) underwent lengthening in 19 sessions. The mean follow-up period was 18.8 months. The average length gained was 45.7 ± 10.5 mm, with a distraction rate of 1.0 ± 0.1 mm/day. Complications requiring return to the operating room occurred in 16% of cases, while 5.3% had minor unresolved issues at treatment completion. Radiographic analysis revealed favorable regenerate morphology, and no case showed regenerate insufficiency. Statistical comparison revealed a significantly higher distraction rate in femoral versus tibial lengthenings ( p = 0.036). Conclusions: Fully internal limb lengthening using magnetically controlled nails is a safe and effective option for adolescents and young adults, with a low rate of complications and high-quality regenerate formation. These findings support broader adoption of internal lengthening in younger patients, particularly in centers with trained teams and appropriate patient selection. limb lengthening PRECICE adolescent orthopedics internal nailing deformity correction Figures Figure 1 Figure 2 Background In recent years, fully internal limb lengthening techniques have gained preference in deformity correction and limb reconstruction. The main goals of these approaches are to minimize transfixation of soft tissues, facilitate early and efficient rehabilitation, avoid complications specific to external fixation—such as pin site infections—and achieve a more cosmetically acceptable surgical site. In addition to preserving joint range of motion in adjacent joints, excellent regenerate bone healing has been reported with these methods (1). However, the application of these internal lengthening techniques remains limited in the pediatric population. The primary concern lies in the potential risk of physeal injury during nail insertion. Therefore, these methods are generally reserved for patients with minimal remaining growth potential, or in cases where the adjacent physis is already damaged or functionally closed. When internal lengthening is feasible in such cases, motorized nails have demonstrated notably low complication rates (2). In patients where this approach is contraindicated, external fixators or growth-guidance techniques remain the mainstay. Recently, an increasing number of case series involving adolescent patients undergoing fully internal limb lengthening have been published (3). These studies predominantly focus on complications, particularly those requiring reoperation(4, 5). In this study, we aimed to evaluate the clinical and radiological outcomes of limb lengthening procedures performed with magnetically controlled intramedullary nails in adolescent and young adult patients treated in our institution. Material and Methods Between 2022 and 2024, all limb lengthening procedures performed using a fully internal, magnetically controlled intramedullary lengthening nail (PRECICE®, Ellipse Technologies, Inc., Irvine, San Diego, CA) under national health insurance coverage were retrospectively reviewed after receiving approval from the institutional review board (IRB). The study included all patients aged 18 years or younger who had undergone fully internal limb lengthening and had a minimum follow-up duration of 9 months (Table 1). Inclusion criteria were: age ≤18 years at the time of surgery, use of the PRECICE nail for lower or upper limb lengthening, and availability of clinical and radiographic data for at least 9 months postoperatively. Exclusion criteria included: patients older than 18 years at the time of surgery, patients with metabolic bone diseases (e.g., rickets, osteomalacia), active or recent infections at the surgical site, previous surgeries on the same segment that may interfere with regenerate quality assessment, and incomplete or missing follow-up data. Patients older than 18 years, including 8 procedures in 7 patients, were excluded from the analysis. All procedures were performed using different lengths and diameters of the same intramedullary nail system. A 4.5 mm drill was used to create a percutaneous vent hole prior to reaming. Sequential reaming was performed to 1.5 mm above the planned nail diameter. Osteotomy was achieved using a multiple-drill percutaneous technique. Minor deformity corrections were made intraoperatively using poller screws during nail insertion. Postoperative rehabilitation was conducted by a dedicated orthopedic rehabilitation team experienced in limb lengthening. Distraction was initiated at a rate of 1 mm per day and continued until the target length was achieved. Full weight-bearing was permitted from the first postoperative day, as tolerated by the patient. To prevent joint contractures during the distraction phase, all patients were enrolled in a structured physiotherapy program supervised by a specialized team. Bracing was used selectively depending on the osteotomy site and adjacent joint risks. For femoral lengthenings, dynamic knee extension braces were employed when quadriceps tightness or reduced range of motion was observed. In tibial lengthenings, ankle-foot orthoses (AFOs) were prescribed as needed to maintain neutral ankle positioning. Compliance with bracing and therapy protocols was monitored during follow-up visits. Follow-up evaluations were conducted biweekly and included physical examination and plain radiographs. Regenerate bone quality was assessed on standard anteroposterior and lateral radiographs taken at each visit. The Li classification system was utilized to grade regenerate quality, considering five morphological shapes (fusiform, cylindrical, concave, lateral, and central) and three density categories: low, intermediate, and normal, in addition to the number and continuity of visible cortices and overall radiodensity across the distraction gap (6) . Decisions regarding full weight-bearing and nail removal were made based on these standardized radiographic criteria. Full weight-bearing was achieved in all patients within the first month after completion of the distraction phase. Patients were categorized into two groups based on the occurrence of complications during treatment. These groups were compared in terms of age, etiology, lengthened segment, laterality (unilateral/bilateral), distraction parameters, and regenerate quality. Descriptive statistics were presented as mean, standard deviation, median, minimum, maximum, frequency, and percentage. Group comparisons between patients with and without complications were performed using the independent samples t-test or the Mann–Whitney U test, depending on the distribution of the variables. Categorical variables were compared using the Chi-square test. Spearman correlation analysis was used to assess the relationship between the distraction rate and the lengthened segment. All analyses were performed using SPSS version 27.0. Table 1: Demographic, Clinical, and Treatment Characteristics of Patients Undergoing Intramedullary Limb Lengthening with Magnetic Nails No Etiology Age Follow-Up (months) Segment */ † Lengthening Amount (mm) / Distraction Rate (mm/day) Complications How i t is solved 1 Fibular Hemimelia (Final Lengthening) 17 30,9 Femur 70 / 1,08 none 2 Idiopathic 14 29,5 Tibia 30 / 0,94 none 3 Konjenital Short Femur 16 29,0 Femur 60 / 1,11 none 4 Short Stature 18 22,9 Tibia (b) 50 / 0,94 Abnormal Mechanical Axis Deviation Planned Revision during Implant Removal 5 Konjenital Short Femur 16 22,7 Femur 30 / 0,94 none 6 Post Infectious 10 22,2 Tibia 45 / 0,96 none 7 Post Traumatic 11 20,5 Femur 40 / 1,00 none 8 Idiopathic 16 18,5 Tibia 30 / 0,94 none 9 Congenital Short Femur 16 17,8 Femur 40 / 1,11 none 10 Osteogenezis İmperfecta / Post Traumatic 15 17,1 Femur 45 / 0,96 none 11 Bilateral Blount Sequela + Short Stature 14 17,1 Tibia (B) 50 / 1,00 none 12 Short Stature 18 16,9 Femur (b) † 50 / 1,00 none 13 Skeletal Dysplasia 11 15,5 Femur 50 / 1,06 none 14 MHE** 13 13,5 Femur † 50 / 0,96 Mechanism Not Worked Nail extraction, control, re-reaming, reimplanting 15 Post Traumatic 10 11,1 Femur 50 / 1,22 none 16 Idiopathic 16 10,1 Tibia 30 / 0,94 Ankle Equinus Contracture Gastrocunemicus Recession 17 Achondroplasia 16 15,8 Humerus (b) 50 / 1,04 none 18 Achondroplasia 15 13,3 Femur (b) † 50 / 1,00 none 19 CFD Type 1*** 14 14,6 Femur 48 / 1,09 Knee Flexion Contracture Phsical Therapy *(b) : Bilateral lengthening performed in the same session, **MHE : Multiple Hereditary Exositozis, †: Retrograde nailing direction, ***CFD: Congenital Femoral Deficiency Results A total of 24 long bones in 18 patients underwent intramedullary lengthening in 19 separate sessions (Table 1). Five of these cases involved bilateral lengthening (Cases 4, 12, 17, and 18), including bilateral tibia, femur, and humerus procedures. The mean follow-up period was 18.8 months (range: 10.3–30.9 months). The average length gained was 45.7 ± 10.5 mm (range: 30–70 mm). The mean latency period before distraction began was 6.7 ± 2.8 days (range: 1–10 days). The mean distraction duration was 44.9 ± 9.1 days (range: 32–65 days), with a mean distraction rate of 1.0 ± 0.1 mm/day (range: 0.9–1.2 mm/day). A total of four complications occurred in four patients during treatment. Two of these required return to the operating room. In one case, reoperation was recommended but postponed at the patient's request. One complication was resolved with orthopedic rehabilitation alone. In Case 4, a patient undergoing bilateral tibial lengthening for short stature, abnormal mechanical axis deviation was observed. Retrospective analysis indicated that this was due to an incorrect entry point and lack of poller screw use. The deformity was corrected during implant removal with a controlled osteotomy. In Case 14, a patient with Multiple Hereditary Exostosis underwent femoral deformity correction and lengthening. On postoperative day 10, nail distraction was found to be nonfunctional. The nail was removed and tested intraoperatively, showing normal function. A repeat reaming was performed, the nail was reinserted, and distraction proceeded without further issues (Figure 1). In Case 16, despite a relatively small length gain, a persistent ankle equinus contracture was observed at the end of treatment. The patient underwent open gastrocnemius recession and was immobilized with a soft cast. Recovery was completed after 6 weeks. In Case 19, a patient developed increased knee flexion contracture after completion of treatment, which was resolved with aggressive physical therapy. Among the 24 lengthening procedures, Type 1 or 2 callus morphology was observed in 6 cases, Type 3 in 5 cases, and Type 4 in 2 cases. In 12 procedures, the regenerate bone exhibited moderate to high radiological density. No case demonstrated poor or insufficient callus formation. Although transient reductions in joint range of motion were noted during treatment in several patients, these resolved spontaneously after regenerate maturation and treatment completion. Therefore, in line with previous literature, these were not considered complications (7, 8). When patients were grouped based on the presence or absence of complications, no statistically significant differences were found in age, etiology, amount of lengthening, latency period, duration of distraction, distraction rate, direction of nailing, or regenerate quality (p > 0.05). However, correlation analysis revealed that the distraction rate was significantly higher in femoral lengthening procedures compared to tibial procedures (p < 0.05). Specifically: Femur group: min–max = 0.938–1.220 mm/day, median = 1.032, mean ± SD = 1.043 ± 0.084, Tibia group: min–max = 0.938–1.000 mm/day, median = 0.940, mean ± SD = 0.952 ± 0.025 (Kruskal–Wallis test, Mann–Whitney U post hoc; p = 0.036) Discussion Fully internal limb lengthening using magnetically controlled intramedullary nails has become increasingly popular in recent years due to their low complication rates, the absence of transfixation-related issues such as pin site infections, and the facilitation of early and effective rehabilitation. Compared to circular external fixators—complex systems requiring a steep learning curve—magnetic nails offer a technically straightforward alternative, broadening the appeal of lengthening procedures for both surgeons and patients. These nails allow for safe and comfortable distraction osteogenesis without the mechanical or electronic failures historically associated with earlier systems. However, disparities in healthcare access and economic resources across countries limit the availability of motorized internal lengthening nails, particularly in developing regions. In Turkey, their use is permitted under national health insurance only under specific indications and with prior authorization. Approval is granted for patients with a limb length discrepancy greater than 2 cm and no contraindications to intramedullary nailing, as well as for patients with height percentiles below the 10th percentile due to congenital, genetic, or metabolic conditions. Our center opened in May 2020 as the largest and most advanced hospital in our region. The first magnetic nail procedure was performed in 2022, and the limb lengthening program remains active. All procedures in this study were performed by surgeons with formal fellowship training in limb lengthening and deformity correction. To maintain a homogenous adolescent and young adult cohort, patients older than 18 years—most of whom had post-traumatic etiologies—were excluded. In our retrospective cohort, the rate of complications requiring reoperation was 16%, and minor complications unresolved at the end of treatment were seen in 5.3% of cases. These complications were infrequent and generally manageable. Among the 19 patients, three required reoperation: one for planned correction of a mechanical axis deviation during implant removal, one for distraction mechanism failure necessitating re-reaming and re-implantation, and one for gastrocnemius recession due to ankle equinus contracture. These cases posed both technical and biological challenges but were successfully resolved without long-term sequelae. Compared to previous studies, our overall reoperation rate (16%) is lower than those reported by Shabtai et al. (38.9%) and Vogt et al. (26.6%), both of which included higher proportions of complex congenital deformities (3, 5) . Minor complications, such as knee flexion contractures or mild axis deviations, were observed but did not require surgical intervention in most cases. Similar patterns were reported by Iliadis et al. and Masci et al., who noted transient complications that resolved with conservative management (9, 10) . The relatively low rate of complications in our series may reflect the experience of the surgical team, strict adherence to physiotherapy protocols, and the structured patient selection criteria used in our institution. Furthermore, the use of internal lengthening systems eliminates risks associated with external fixators, such as pin site infections or neurovascular tethering, contributing to an overall safer profile. Although we did not perform a separate statistical analysis comparing bone regeneration rates between congenital and acquired etiologies due to sample size limitations, it is important to note that congenital cases may present with unique anatomical and biological challenges. Previous studies have suggested that such deformities can be associated with prolonged healing indices and higher complication rates compared to post-traumatic or idiopathic etiologies (3, 5) . However, in our cohort, clinical outcomes were favorable across both congenital and acquired groups, and no consistent trend of delayed consolidation was observed in congenital cases. This suggests that with proper patient selection and surgical technique, magnetically controlled limb lengthening can be successfully applied in congenital conditions. Further subgroup analyses in larger series may help to clarify whether etiology significantly influences regenerate quality or healing time. The application of magnetically controlled intramedullary nails in pediatric and adolescent patients has become increasingly feasible, with some studies reporting safe use in children as young as 8 years, especially with femoral antegrade nailing (4, 11, 12). In our series, one 10-year-old patient underwent antegrade femoral lengthening without complication, supporting findings from the literature. Iobst et al. confirmed the safety and efficacy of these devices even in patients with programmable implantable devices, with all patients achieving target lengths without mechanical failure (13). Iliadis et al. (2020) and Masci et al. (2021) both reported effective outcomes with low complication rates in pediatric populations using the PRECICE system (9, 10). Calder et al. (2019) showed that both antegrade and retrograde femoral approaches using PRECICE nails yielded comparable results (14). In bilateral applications, Vogt et al. reported no major complications resulting in permanent sequelae but did note minor issues, including two repeat osteotomies and one nail exchange(5). In contrast, none of our bilateral cases resulted in long-term impairment, though one required planned deformity correction during implant removal and another involved a temporary distraction mechanism failure, resolved surgically. Similarly, Al-Sayyad et al. reported effective lengthening with minimal complications using magnetically driven nails in 15 patients(15). The primary limitation of our study is the relatively small sample size and its retrospective design. Nevertheless, we believe our findings provide meaningful insights into the clinical and radiological outcomes of internal limb lengthening in adolescents and young adults. Future prospective studies with larger, more homogeneous cohorts are needed to validate these findings and enhance the evidence base. Despite its limitations, our study supports the expanding role of magnetic intramedullary lengthening in routine pediatric and adolescent orthopedic practice Conclusion Magnetically controlled intramedullary lengthening nails represent a safe and effective option for limb lengthening in adolescent and young adult patients, offering low complication rates and favorable radiological and functional outcomes. When applied by experienced teams under appropriate indications, this technique provides a reliable alternative to external fixation, especially in centers with access to modern limb reconstruction technologies. However, further prospective studies with larger cohorts are needed to validate and generalize these findings. Declarations Funding: This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Conflicts of Interest: The authors declare that they have no conflicts of interest. Ethical Approval: This study was conducted in accordance with institutional guidelines and approved by the local ethics committee prior to data collection. References Iobst CA, Rozbruch SR, Nelson S, Fragomen A. Simultaneous Acute Femoral Deformity Correction and Gradual Limb Lengthening Using a Retrograde Femoral Nail: Technique and Clinical Results. J Am Acad Orthop Surg. 2018;26(7):241-50. Black SR, Kwon MS, Cherkashin AM, Samchukov ML, Birch JG, Jo CH. Lengthening in Congenital Femoral Deficiency: A Comparison of Circular External Fixation and a Motorized Intramedullary Nail. The Journal of bone and joint surgery American volume. 2015;97(17):1432-40. Shabtai L, Specht SC, Standard SC, Herzenberg JE. Internal lengthening device for congenital femoral deficiency and fibular hemimelia. Clinical orthopaedics and related research. 2014;472(12):3860-8. Frommer A, Rödl R, Gosheger G, Vogt B. [Application of motorized intramedullary lengthening nails in skeletally immature patients : Indications and limitations]. Unfallchirurg. 2018;121(11):860-7. Vogt B, Laufer A, Gosheger G, Toporowski G, Antfang C, Rölfing JD, et al. Evaluation of simultaneous bilateral femoral distraction osteogenesis with antegrade intramedullary lengthening nails in achondroplasia with rhizomelic short stature: a retrospective study of 15 patients with a minimum follow-up of 2 years. Acta orthopaedica. 2024;95:47-54. Li R, Saleh M, Yang L, Coulton L. Radiographic classification of osteogenesis during bone distraction. Journal of orthopaedic research : official publication of the Orthopaedic Research Society. 2006;24(3):339-47. Kocaoglu M, Eralp L, Kilicoglu O, Burc H, Cakmak M. Complications encountered during lengthening over an intramedullary nail. The Journal of bone and joint surgery American volume. 2004;86(11):2406-11. Paley D. Problems, obstacles, and complications of limb lengthening by the Ilizarov technique. Clinical orthopaedics and related research. 1990(250):81-104. Masci G, Palmacci O, Vitiello R, Bonfiglio N, Bocchi MB, Cipolloni V, et al. Limb lengthening with PRECICE magnetic nail in pediatric patients: A systematic review. World J Orthop. 2021;12(8):575-83. Iliadis AD, Palloni V, Wright J, Goodier D, Calder P. Pediatric Lower Limb Lengthening Using the PRECICE Nail: Our Experience With 50 Cases. Journal of pediatric orthopedics. 2021;41(1):e44-e9. Radler C, Mindler GT, Stauffer A, Weiß C, Ganger R. Limb Lengthening With Precice Intramedullary Lengthening Nails in Children and Adolescents. Journal of pediatric orthopedics. 2022;42(2):e192-e200. Hammouda AI, Jauregui JJ, Gesheff MG, Standard SC, Herzenberg JE. Trochanteric Entry for Femoral Lengthening Nails in Children: Is It Safe? Journal of pediatric orthopedics. 2017;37(4):258-64. Iobst CA, Hatfield DN, Forro SD, Quinnan SM. Magnetically Driven Intramedullary Limb Lengthening in Patients with Pre-existing Implanted Programmable Devices: A Case Series. Strategies Trauma Limb Reconstr. 2023;18(2):111-6. Calder PR, McKay JE, Timms AJ, Roskrow T, Fugazzotto S, Edel P, et al. Femoral lengthening using the Precice intramedullary limb-lengthening system: outcome comparison following antegrade and retrograde nails. Bone Joint J. 2019;101-b(9):1168-76. Al-Sayyad MJ, Alshoaibi FA, Alshuaibi AA, Almohammadi AF, Almaghrabi HA, Alsaady AM, et al. Results of Lower Limb Bone Lengthening by Using Motorized and Magnet-Driven Intramedullary Nails to Treat Limb Length Discrepancy. Cureus. 2025;17(1):e77212. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 16 Jun, 2025 Read the published version in Journal of Orthopaedic Surgery and Research → Version 1 posted First submitted to journal 28 May, 2025 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-6727984","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":463288543,"identity":"a7a31fd4-9130-49eb-be14-ff416ed38e05","order_by":0,"name":"Mehmet Ali Talmaç","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA2klEQVRIiWNgGAWjYDCCA0D8AIj52RuApIEFMVqYGRgSgLRkD0izgQQJWgxugEgGIrTw3T5/8ENijp08w83nVzf8KJBg4G/vTsCrRfJcMrNE4rZkw8bZOWU3e4AOkzhzdgNeLQZnmBmAWpgTmKVz0m7wALUYSOQS1ML8I3FbfQKb5Jm0m3+I1MIGtOVwAo8E+7HbRNkieYbZzCJx23HDGTw5bLdlDCR4CPqF7wzj4xsft1XL2x8//uzmmz82cvztvfi1IAEeAzBJrHIQYH9AiupRMApGwSgYQQAAmF9Hhq/lbmQAAAAASUVORK5CYII=","orcid":"","institution":"Başakşehir Çam ve Sakura City Hospital","correspondingAuthor":true,"prefix":"","firstName":"Mehmet","middleName":"Ali","lastName":"Talmaç","suffix":""},{"id":463288544,"identity":"756a96f6-e845-4670-acc1-c9dfdf77081e","order_by":1,"name":"Melih Civan","email":"","orcid":"","institution":"Başakşehir Çam ve Sakura City Hospital","correspondingAuthor":false,"prefix":"","firstName":"Melih","middleName":"","lastName":"Civan","suffix":""},{"id":463288545,"identity":"9252561c-e8a0-40f4-b815-23e765e6d7e6","order_by":2,"name":"Ergün Mendes","email":"","orcid":"","institution":"Koç University","correspondingAuthor":false,"prefix":"","firstName":"Ergün","middleName":"","lastName":"Mendes","suffix":""}],"badges":[],"createdAt":"2025-05-22 22:08:14","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6727984/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6727984/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s13018-025-06009-2","type":"published","date":"2025-06-16T15:57:11+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":83681205,"identity":"6994b23e-210d-4d11-824d-e5f9cffddcba","added_by":"auto","created_at":"2025-05-30 16:11:13","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":587542,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003ePreoperative planning and complication management in a patient with Multiple Hereditary Exostosis undergoing femoral lengthening.\u003cbr\u003e\n(a) Preoperative orthoroentgenogram showing left distal femoral varus deformity and limb length discrepancy in a 13-year-old male patient. Solid line indicates the ideal mechanical axis of the femur; dashed line represents the mechanical axis of the tibia extended proximally. The single arrow shows the planned osteotomy level; the double-headed arrow indicates the direction of intramedullary nail placement post-deformity correction.\u003cbr\u003e\n(b–c) Postoperative radiographs on day 10 showing failure of the lengthening mechanism.\u003cbr\u003e\n(d) Intraoperative image demonstrating removal of the nail, functional testing outside the body, repeat reaming, and successful reinsertion.\u003cbr\u003e\n(e–f) Three-month postoperative radiographs demonstrating a Type 1 regenerate with good density and maturation.\u003cbr\u003e\n(g–h) One-year postoperative long-standing AP radiograph and scoliosis survey image showing maintained alignment.\u003c/em\u003e\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-6727984/v1/1036cdd8923c92591c6430ba.png"},{"id":83681627,"identity":"3e875923-28ef-463a-b82c-aa9c65679004","added_by":"auto","created_at":"2025-05-30 16:19:13","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":193474,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eGradual correction of ankle equinus contracture during rehabilitation in a 16-year-old patient.\u003cbr\u003e\nSequential orthoroentgenograms of Case 8 show initial non-weight-bearing of the heel during distraction phase. Over time, with targeted orthopedic rehabilitation, the ankle joint levels equalized and heel strike improved.\u003c/em\u003e\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-6727984/v1/13a8ab4c2053d6752443473e.png"},{"id":85231427,"identity":"60b7ce88-f7c6-43ec-8eb0-f82fc80440d9","added_by":"auto","created_at":"2025-06-23 16:07:50","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3313692,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6727984/v1/4f76a04c-d14b-4062-b6f2-d3aefb609889.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Clinical and Radiological Outcomes of Magnetically Controlled Intramedullary Lengthening Nails in Adolescents and Young Adults: A Retrospective Cohort Study","fulltext":[{"header":"Background","content":"\u003cp\u003eIn recent years, fully internal limb lengthening techniques have gained preference in deformity correction and limb reconstruction. The main goals of these approaches are to minimize transfixation of soft tissues, facilitate early and efficient rehabilitation, avoid complications specific to external fixation—such as pin site infections—and achieve a more cosmetically acceptable surgical site. In addition to preserving joint range of motion in adjacent joints, excellent regenerate bone healing has been reported with these methods (1).\u003c/p\u003e\n\u003cp\u003eHowever, the application of these internal lengthening techniques remains limited in the pediatric population. The primary concern lies in the potential risk of physeal injury during nail insertion. Therefore, these methods are generally reserved for patients with minimal remaining growth potential, or in cases where the adjacent physis is already damaged or functionally closed. When internal lengthening is feasible in such cases, motorized nails have demonstrated notably low complication rates (2). In patients where this approach is contraindicated, external fixators or growth-guidance techniques remain the mainstay.\u003c/p\u003e\n\u003cp\u003eRecently, an increasing number of case series involving adolescent patients undergoing fully internal limb lengthening have been published (3). These studies predominantly focus on complications, particularly those requiring reoperation(4, 5).\u003c/p\u003e\n\u003cp\u003eIn this study, we aimed to evaluate the clinical and radiological outcomes of limb lengthening procedures performed with magnetically controlled intramedullary nails in adolescent and young adult patients treated in our institution.\u003c/p\u003e"},{"header":"Material and Methods","content":"\u003cp\u003eBetween 2022 and 2024, all limb lengthening procedures performed using a fully internal, magnetically controlled intramedullary lengthening nail (PRECICE\u0026reg;, Ellipse Technologies, Inc., Irvine, San Diego, CA) under national health insurance coverage were retrospectively reviewed after receiving approval from the institutional review board (IRB). The study included all patients aged 18 years or younger who had undergone fully internal limb lengthening and had a minimum follow-up duration of 9 months (Table 1).\u0026nbsp;\u003cstrong\u003eInclusion criteria were: age \u0026le;18 years at the time of surgery, use of the PRECICE nail for lower or upper limb lengthening, and availability of clinical and radiographic data for at least 9 months postoperatively. Exclusion criteria included: patients older than 18 years at the time of surgery, patients with metabolic bone diseases (e.g., rickets, osteomalacia), active or recent infections at the surgical site, previous surgeries on the same segment that may interfere with regenerate quality assessment, and incomplete or missing follow-up data.\u003c/strong\u003ePatients older than 18 years, including 8 procedures in 7 patients, were excluded from the analysis.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAll procedures were performed using different lengths and diameters of the same intramedullary nail system. A 4.5 mm drill was used to create a percutaneous vent hole prior to reaming. Sequential reaming was performed to 1.5 mm above the planned nail diameter. Osteotomy was achieved using a multiple-drill percutaneous technique. Minor deformity corrections were made intraoperatively using poller screws during nail insertion. Postoperative rehabilitation was conducted by a dedicated orthopedic rehabilitation team experienced in limb lengthening.\u003c/p\u003e\n\u003cp\u003eDistraction was initiated at a rate of 1 mm per day and continued until the target length was achieved. Full weight-bearing was permitted from the first postoperative day, as tolerated by the patient.\u0026nbsp;\u003cstrong\u003eTo prevent joint contractures during the distraction phase, all patients were enrolled in a structured physiotherapy program supervised by a specialized team. Bracing was used selectively depending on the osteotomy site and adjacent joint risks. For femoral lengthenings, dynamic knee extension braces were employed when quadriceps tightness or reduced range of motion was observed. In tibial lengthenings, ankle-foot orthoses (AFOs) were prescribed as needed to maintain neutral ankle positioning. Compliance with bracing and therapy protocols was monitored during follow-up visits.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFollow-up evaluations were conducted biweekly and included physical examination and plain radiographs.\u0026nbsp;\u003cstrong\u003eRegenerate bone quality was assessed on standard anteroposterior and lateral radiographs taken at each visit. The Li classification system was utilized to grade regenerate quality, considering five morphological shapes (fusiform, cylindrical, concave, lateral, and central) and three density categories: low, intermediate, and normal, in addition to the number and continuity of visible cortices and overall radiodensity across the distraction gap\u003c/strong\u003e\u003cstrong\u003e(6)\u003c/strong\u003e\u003cstrong\u003e. Decisions regarding full weight-bearing and nail removal were made based on these standardized radiographic criteria.\u003c/strong\u003eFull weight-bearing was achieved in all patients within the first month after completion of the distraction phase. Patients were categorized into two groups based on the occurrence of complications during treatment. These groups were compared in terms of age, etiology, lengthened segment, laterality (unilateral/bilateral), distraction parameters, and regenerate quality.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDescriptive statistics were presented as mean, standard deviation, median, minimum, maximum, frequency, and percentage. Group comparisons between patients with and without complications were performed using the independent samples t-test or the Mann\u0026ndash;Whitney U test, depending on the distribution of the variables. Categorical variables were compared using the Chi-square test. Spearman correlation analysis was used to assess the relationship between the distraction rate and the lengthened segment. All analyses were performed using SPSS version 27.0.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"633\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"8\" style=\"width: 633px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eTable 1: Demographic, Clinical, and Treatment Characteristics of Patients Undergoing Intramedullary Limb Lengthening with Magnetic Nails\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eNo\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEtiology\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFollow-Up (months)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSegment\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e*/\u003c/strong\u003e\u0026dagger;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLengthening Amount (mm) / Distraction Rate (mm/day)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eComplications\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHow\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003ei\u003c/strong\u003e\u003cstrong\u003et is solved\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e1\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eFibular Hemimelia\u003c/p\u003e\n \u003cp\u003e(Final Lengthening)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e30,9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFemur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e70 / 1,08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e2\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eIdiopathic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e29,5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eTibia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e30 / 0,94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e3\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eKonjenital Short Femur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e29,0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFemur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e60 / 1,11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e4\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eShort Stature\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e22,9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eTibia (b)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e50 / 0,94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eAbnormal Mechanical Axis Deviation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003ePlanned Revision during Implant Removal\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e5\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eKonjenital Short Femur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e22,7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFemur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e30 / 0,94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e6\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003ePost\u0026nbsp;Infectious\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e22,2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eTibia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e45 / 0,96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e7\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003ePost Traumatic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e20,5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFemur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e40 / 1,00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e8\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eIdiopathic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e18,5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eTibia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e30 / 0,94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e9\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eCongenital Short Femur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e17,8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFemur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e40 / 1,11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e10\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eOsteogenezis İmperfecta / Post Traumatic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e17,1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFemur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e45 / 0,96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e11\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eBilateral Blount Sequela + Short Stature\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e17,1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eTibia (B)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e50 / 1,00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e12\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eShort Stature\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e16,9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFemur (b) \u003cstrong\u003e\u003csup\u003e\u0026dagger;\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e50 / 1,00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e13\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eSkeletal Dysplasia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e15,5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFemur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e50 / 1,06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e14\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eMHE**\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e13,5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFemur \u003cstrong\u003e\u003csup\u003e\u0026dagger;\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e50 / 0,96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eMechanism Not Worked\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003eNail extraction, control, re-reaming, reimplanting\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e15\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003ePost Traumatic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e11,1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFemur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e50 / 1,22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e16\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eIdiopathic\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e10,1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eTibia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e30 / 0,94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eAnkle Equinus Contracture\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003eGastrocunemicus Recession\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e17\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eAchondroplasia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e15,8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eHumerus (b)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e50 / 1,04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e18\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eAchondroplasia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e13,3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFemur (b) \u003cstrong\u003e\u003csup\u003e\u0026dagger;\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e50 / 1,00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003enone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 28px;\"\u003e\n \u003cp\u003e\u003cem\u003e19\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 132px;\"\u003e\n \u003cp\u003eCFD Type 1***\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 38px;\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e14,6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003eFemur\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e48 / 1,09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eKnee Flexion Contracture\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003ePhsical Therapy\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003e*(b)\u003c/em\u003e\u003c/strong\u003e\u003cem\u003e: Bilateral lengthening performed in the same session, \u003cstrong\u003e**MHE\u003c/strong\u003e: Multiple Hereditary Exositozis, \u003cstrong\u003e\u0026dagger;:\u003c/strong\u003e Retrograde nailing direction, \u003cstrong\u003e***CFD:\u003c/strong\u003e Congenital Femoral Deficiency\u003c/em\u003e\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 24 long bones in 18 patients underwent intramedullary lengthening in 19 separate sessions (Table 1). Five of these cases involved bilateral lengthening (Cases 4, 12, 17, and 18), including bilateral tibia, femur, and humerus procedures. The mean follow-up period was 18.8 months (range: 10.3\u0026ndash;30.9 months). The average length gained was 45.7 \u0026plusmn; 10.5 mm (range: 30\u0026ndash;70 mm). The mean latency period before distraction began was 6.7 \u0026plusmn; 2.8 days (range: 1\u0026ndash;10 days). The mean distraction duration was 44.9 \u0026plusmn; 9.1 days (range: 32\u0026ndash;65 days), with a mean distraction rate of 1.0 \u0026plusmn; 0.1 mm/day (range: 0.9\u0026ndash;1.2 mm/day).\u003c/p\u003e\n\u003cp\u003eA total of four complications occurred in four patients during treatment. Two of these required return to the operating room. In one case, reoperation was recommended but postponed at the patient\u0026apos;s request. One complication was resolved with orthopedic rehabilitation alone.\u003c/p\u003e\n\u003cp\u003eIn Case 4, a patient undergoing bilateral tibial lengthening for short stature, abnormal mechanical axis deviation was observed. Retrospective analysis indicated that this was due to an incorrect entry point and lack of poller screw use. The deformity was corrected during implant removal with a controlled osteotomy.\u003c/p\u003e\n\u003cp\u003eIn Case 14, a patient with Multiple Hereditary Exostosis underwent femoral deformity correction and lengthening. On postoperative day 10, nail distraction was found to be nonfunctional. The nail was removed and tested intraoperatively, showing normal function. A repeat reaming was performed, the nail was reinserted, and distraction proceeded without further issues (Figure 1).\u003c/p\u003e\n\u003cp\u003eIn Case 16, despite a relatively small length gain, a persistent ankle equinus contracture was observed at the end of treatment. The patient underwent open gastrocnemius recession and was immobilized with a soft cast. Recovery was completed after 6 weeks.\u003c/p\u003e\n\u003cp\u003eIn Case 19, a patient developed increased knee flexion contracture after completion of treatment, which was resolved with aggressive physical therapy.\u003c/p\u003e\n\u003cp\u003eAmong the 24 lengthening procedures, Type 1 or 2 callus morphology was observed in 6 cases, Type 3 in 5 cases, and Type 4 in 2 cases. In 12 procedures, the regenerate bone exhibited moderate to high radiological density. No case demonstrated poor or insufficient callus formation.\u003c/p\u003e\n\u003cp\u003eAlthough transient reductions in joint range of motion were noted during treatment in several patients, these resolved spontaneously after regenerate maturation and treatment completion. Therefore, in line with previous literature, these were not considered complications (7, 8).\u003c/p\u003e\n\u003cp\u003eWhen patients were grouped based on the presence or absence of complications, no statistically significant differences were found in age, etiology, amount of lengthening, latency period, duration of distraction, distraction rate, direction of nailing, or regenerate quality (p \u0026gt; 0.05). However, correlation analysis revealed that the distraction rate was significantly higher in femoral lengthening procedures compared to tibial procedures (p \u0026lt; 0.05).\u003cbr\u003e\u0026nbsp;Specifically: Femur group: min\u0026ndash;max = 0.938\u0026ndash;1.220 mm/day, median = 1.032, mean \u0026plusmn; SD = 1.043 \u0026plusmn; 0.084, Tibia group: min\u0026ndash;max = 0.938\u0026ndash;1.000 mm/day, median = 0.940, mean \u0026plusmn; SD = 0.952 \u0026plusmn; 0.025 (Kruskal\u0026ndash;Wallis test, Mann\u0026ndash;Whitney U post hoc; p = 0.036)\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eFully internal limb lengthening using magnetically controlled intramedullary nails has become increasingly popular in recent years due to their low complication rates, the absence of transfixation-related issues such as pin site infections, and the facilitation of early and effective rehabilitation. Compared to circular external fixators—complex systems requiring a steep learning curve—magnetic nails offer a technically straightforward alternative, broadening the appeal of lengthening procedures for both surgeons and patients. These nails allow for safe and comfortable distraction osteogenesis without the mechanical or electronic failures historically associated with earlier systems.\u003c/p\u003e\n\u003cp\u003eHowever, disparities in healthcare access and economic resources across countries limit the availability of motorized internal lengthening nails, particularly in developing regions. In Turkey, their use is permitted under national health insurance only under specific indications and with prior authorization. Approval is granted for patients with a limb length discrepancy greater than 2 cm and no contraindications to intramedullary nailing, as well as for patients with height percentiles below the 10th percentile due to congenital, genetic, or metabolic conditions.\u003c/p\u003e\n\u003cp\u003eOur center opened in May 2020 as the largest and most advanced hospital in our region. The first magnetic nail procedure was performed in 2022, and the limb lengthening program remains active. All procedures in this study were performed by surgeons with formal fellowship training in limb lengthening and deformity correction. To maintain a homogenous adolescent and young adult cohort, patients older than 18 years—most of whom had post-traumatic etiologies—were excluded.\u003c/p\u003e\n\u003cp\u003eIn our retrospective cohort, the rate of complications requiring reoperation was 16%, and minor complications unresolved at the end of treatment were seen in 5.3% of cases.\u0026nbsp;\u003cstrong\u003eThese complications were infrequent and generally manageable. Among the 19 patients, three required reoperation: one for planned correction of a mechanical axis deviation during implant removal, one for distraction mechanism failure necessitating re-reaming and re-implantation, and one for gastrocnemius recession due to ankle equinus contracture. These cases posed both technical and biological challenges but were successfully resolved without long-term sequelae.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompared to previous studies, our overall reoperation rate (16%) is lower than those reported by Shabtai et al. (38.9%) and Vogt et al. (26.6%), both of which included higher proportions of complex congenital deformities\u003c/strong\u003e\u003cstrong\u003e(3, 5)\u003c/strong\u003e\u003cstrong\u003e. Minor complications, such as knee flexion contractures or mild axis deviations, were observed but did not require surgical intervention in most cases. Similar patterns were reported by Iliadis et al. and Masci et al., who noted transient complications that resolved with conservative management\u003c/strong\u003e\u003cstrong\u003e(9, 10)\u003c/strong\u003e\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eThe relatively low rate of complications in our series may reflect the experience of the surgical team, strict adherence to physiotherapy protocols, and the structured patient selection criteria used in our institution. Furthermore, the use of internal lengthening systems eliminates risks associated with external fixators, such as pin site infections or neurovascular tethering, contributing to an overall safer profile.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAlthough we did not perform a separate statistical analysis comparing bone regeneration rates between congenital and acquired etiologies due to sample size limitations, it is important to note that congenital cases may present with unique anatomical and biological challenges. Previous studies have suggested that such deformities can be associated with prolonged healing indices and higher complication rates compared to post-traumatic or idiopathic etiologies\u003c/strong\u003e\u003cstrong\u003e(3, 5)\u003c/strong\u003e\u003cstrong\u003e. However, in our cohort, clinical outcomes were favorable across both congenital and acquired groups, and no consistent trend of delayed consolidation was observed in congenital cases. This suggests that with proper patient selection and surgical technique, magnetically controlled limb lengthening can be successfully applied in congenital conditions. Further subgroup analyses in larger series may help to clarify whether etiology significantly influences regenerate quality or healing time.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe application of magnetically controlled intramedullary nails in pediatric and adolescent patients has become increasingly feasible, with some studies reporting safe use in children as young as 8 years, especially with femoral antegrade nailing (4, 11, 12). In our series, one 10-year-old patient underwent antegrade femoral lengthening without complication, supporting findings from the literature. Iobst et al. confirmed the safety and efficacy of these devices even in patients with programmable implantable devices, with all patients achieving target lengths without mechanical failure (13). Iliadis et al. (2020) and Masci et al. (2021) both reported effective outcomes with low complication rates in pediatric populations using the PRECICE system (9, 10). Calder et al. (2019) showed that both antegrade and retrograde femoral approaches using PRECICE nails yielded comparable results (14).\u003c/p\u003e\n\u003cp\u003eIn bilateral applications, Vogt et al. reported no major complications resulting in permanent sequelae but did note minor issues, including two repeat osteotomies and one nail exchange(5). \u0026nbsp;In contrast, none of our bilateral cases resulted in long-term impairment, though one required planned deformity correction during implant removal and another involved a temporary distraction mechanism failure, resolved surgically. Similarly, Al-Sayyad et al. reported effective lengthening with minimal complications using magnetically driven nails in 15 patients(15).\u003c/p\u003e\n\u003cp\u003eThe primary limitation of our study is the relatively small sample size and its retrospective design. Nevertheless, we believe our findings provide meaningful insights into the clinical and radiological outcomes of internal limb lengthening in adolescents and young adults. Future prospective studies with larger, more homogeneous cohorts are needed to validate these findings and enhance the evidence base.\u0026nbsp;\u003cstrong\u003eDespite its limitations, our study supports the expanding role of magnetic intramedullary lengthening in routine pediatric and adolescent orthopedic practice\u003c/strong\u003e\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eMagnetically controlled intramedullary lengthening nails represent a safe and effective option for limb lengthening in adolescent and young adult patients, offering low complication rates and favorable radiological and functional outcomes. When applied by experienced teams under appropriate indications, this technique provides a reliable alternative to external fixation, especially in centers with access to modern limb reconstruction technologies. However, further prospective studies with larger cohorts are needed to validate and generalize these findings.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e\u003cbr\u003e\u0026nbsp;This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of Interest:\u003c/strong\u003e\u003cbr\u003e\u0026nbsp;The authors declare that they have no conflicts of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical Approval:\u003c/strong\u003e\u003cbr\u003e\u0026nbsp;This study was conducted in accordance with institutional guidelines and approved by the local ethics committee prior to data collection.\u003c/p\u003e"},{"header":" References","content":"\u003col\u003e\n \u003cli\u003eIobst CA, Rozbruch SR, Nelson S, Fragomen A. Simultaneous Acute Femoral Deformity Correction and Gradual Limb Lengthening Using a Retrograde Femoral Nail: Technique and Clinical Results. J Am Acad Orthop Surg. 2018;26(7):241-50.\u003c/li\u003e\n \u003cli\u003eBlack SR, Kwon MS, Cherkashin AM, Samchukov ML, Birch JG, Jo CH. Lengthening in Congenital Femoral Deficiency: A Comparison of Circular External Fixation and a Motorized Intramedullary Nail. The Journal of bone and joint surgery American volume. 2015;97(17):1432-40.\u003c/li\u003e\n \u003cli\u003eShabtai L, Specht SC, Standard SC, Herzenberg JE. Internal lengthening device for congenital femoral deficiency and fibular hemimelia. Clinical orthopaedics and related research. 2014;472(12):3860-8.\u003c/li\u003e\n \u003cli\u003eFrommer A, R\u0026ouml;dl R, Gosheger G, Vogt B. [Application of motorized intramedullary lengthening nails in skeletally immature patients : Indications and limitations]. Unfallchirurg. 2018;121(11):860-7.\u003c/li\u003e\n \u003cli\u003eVogt B, Laufer A, Gosheger G, Toporowski G, Antfang C, R\u0026ouml;lfing JD, et al. Evaluation of simultaneous bilateral femoral distraction osteogenesis with antegrade intramedullary lengthening nails in achondroplasia with rhizomelic short stature: a retrospective study of 15 patients with a minimum follow-up of 2 years. Acta orthopaedica. 2024;95:47-54.\u003c/li\u003e\n \u003cli\u003eLi R, Saleh M, Yang L, Coulton L. Radiographic classification of osteogenesis during bone distraction. Journal of orthopaedic research : official publication of the Orthopaedic Research Society. 2006;24(3):339-47.\u003c/li\u003e\n \u003cli\u003eKocaoglu M, Eralp L, Kilicoglu O, Burc H, Cakmak M. Complications encountered during lengthening over an intramedullary nail. The Journal of bone and joint surgery American volume. 2004;86(11):2406-11.\u003c/li\u003e\n \u003cli\u003ePaley D. Problems, obstacles, and complications of limb lengthening by the Ilizarov technique. Clinical orthopaedics and related research. 1990(250):81-104.\u003c/li\u003e\n \u003cli\u003eMasci G, Palmacci O, Vitiello R, Bonfiglio N, Bocchi MB, Cipolloni V, et al. Limb lengthening with PRECICE magnetic nail in pediatric patients: A systematic review. World J Orthop. 2021;12(8):575-83.\u003c/li\u003e\n \u003cli\u003eIliadis AD, Palloni V, Wright J, Goodier D, Calder P. Pediatric Lower Limb Lengthening Using the PRECICE Nail: Our Experience With 50 Cases. Journal of pediatric orthopedics. 2021;41(1):e44-e9.\u003c/li\u003e\n \u003cli\u003eRadler C, Mindler GT, Stauffer A, Wei\u0026szlig; C, Ganger R. Limb Lengthening With Precice Intramedullary Lengthening Nails in Children and Adolescents. Journal of pediatric orthopedics. 2022;42(2):e192-e200.\u003c/li\u003e\n \u003cli\u003eHammouda AI, Jauregui JJ, Gesheff MG, Standard SC, Herzenberg JE. Trochanteric Entry for Femoral Lengthening Nails in Children: Is It Safe? Journal of pediatric orthopedics. 2017;37(4):258-64.\u003c/li\u003e\n \u003cli\u003eIobst CA, Hatfield DN, Forro SD, Quinnan SM. Magnetically Driven Intramedullary Limb Lengthening in Patients with Pre-existing Implanted Programmable Devices: A Case Series. Strategies Trauma Limb Reconstr. 2023;18(2):111-6.\u003c/li\u003e\n \u003cli\u003eCalder PR, McKay JE, Timms AJ, Roskrow T, Fugazzotto S, Edel P, et al. Femoral lengthening using the Precice intramedullary limb-lengthening system: outcome comparison following antegrade and retrograde nails. Bone Joint J. 2019;101-b(9):1168-76.\u003c/li\u003e\n \u003cli\u003eAl-Sayyad MJ, Alshoaibi FA, Alshuaibi AA, Almohammadi AF, Almaghrabi HA, Alsaady AM, et al. Results of Lower Limb Bone Lengthening by Using Motorized and Magnet-Driven Intramedullary Nails to Treat Limb Length Discrepancy. Cureus. 2025;17(1):e77212.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-orthopaedic-surgery-and-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"josr","sideBox":"Learn more about [Journal of Orthopaedic Surgery and Research](http://josr-online.biomedcentral.com)","snPcode":"13018","submissionUrl":"https://submission.nature.com/new-submission/13018/3","title":"Journal of Orthopaedic Surgery and Research","twitterHandle":"@MSKmedBMC","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"limb lengthening, PRECICE, adolescent orthopedics, internal nailing, deformity correction","lastPublishedDoi":"10.21203/rs.3.rs-6727984/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6727984/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMagnetically controlled intramedullary lengthening nails offer a fully internal approach to limb lengthening, avoiding complications associated with external fixators such as pin site infections and soft tissue transfixation. While their use in adults is well-documented, evidence regarding their safety and efficacy in adolescents and young adults remains limited.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis retrospective cohort study evaluated the clinical and radiological outcomes of 24 limb lengthening procedures performed in 18 adolescent and young adult patients between 2022 and 2024 using PRECICE® intramedullary lengthening nails. Patients aged ≤18 years with a minimum of 9 months follow-up were included. Lengthening parameters, regenerate morphology, complication rates, and inter-group comparisons were analyzed.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA total of 24 long bone segments (femur, tibia, and humerus) underwent lengthening in 19 sessions. The mean follow-up period was 18.8 months. The average length gained was 45.7 ± 10.5 mm, with a distraction rate of 1.0 ± 0.1 mm/day. Complications requiring return to the operating room occurred in 16% of cases, while 5.3% had minor unresolved issues at treatment completion. Radiographic analysis revealed favorable regenerate morphology, and no case showed regenerate insufficiency. Statistical comparison revealed a significantly higher distraction rate in femoral versus tibial lengthenings (\u003cem\u003ep\u003c/em\u003e= 0.036).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFully internal limb lengthening using magnetically controlled nails is a safe and effective option for adolescents and young adults, with a low rate of complications and high-quality regenerate formation. These findings support broader adoption of internal lengthening in younger patients, particularly in centers with trained teams and appropriate patient selection.\u003c/p\u003e","manuscriptTitle":"Clinical and Radiological Outcomes of Magnetically Controlled Intramedullary Lengthening Nails in Adolescents and Young Adults: A Retrospective Cohort Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-30 16:11:09","doi":"10.21203/rs.3.rs-6727984/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"submitted","content":"Journal of Orthopaedic Surgery and Research","date":"2025-05-28T21:02:27+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-orthopaedic-surgery-and-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"josr","sideBox":"Learn more about [Journal of Orthopaedic Surgery and Research](http://josr-online.biomedcentral.com)","snPcode":"13018","submissionUrl":"https://submission.nature.com/new-submission/13018/3","title":"Journal of Orthopaedic Surgery and Research","twitterHandle":"@MSKmedBMC","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"c077116d-02f1-43a9-83c8-4125dfa46ab9","owner":[],"postedDate":"May 30th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-06-23T16:03:21+00:00","versionOfRecord":{"articleIdentity":"rs-6727984","link":"https://doi.org/10.1186/s13018-025-06009-2","journal":{"identity":"journal-of-orthopaedic-surgery-and-research","isVorOnly":false,"title":"Journal of Orthopaedic Surgery and Research"},"publishedOn":"2025-06-16 15:57:11","publishedOnDateReadable":"June 16th, 2025"},"versionCreatedAt":"2025-05-30 16:11:09","video":"","vorDoi":"10.1186/s13018-025-06009-2","vorDoiUrl":"https://doi.org/10.1186/s13018-025-06009-2","workflowStages":[]},"version":"v1","identity":"rs-6727984","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6727984","identity":"rs-6727984","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}