Patient-Specific 3D-Printed Scaffold for Pediatric Superior Sternal Cleft Repair

Patient-Specific 3D-Printed Scaffold for Pediatric Superior Sternal Cleft Repair | 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 Case Report Patient-Specific 3D-Printed Scaffold for Pediatric Superior Sternal Cleft Repair Hayrünisa Kahraman Esen, Mustafa Yüksel, Mehmet Oğuzhan Özyurtkan This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7765634/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 21 Apr, 2026 Read the published version in Journal of Cardiothoracic Surgery → Version 1 posted 14 You are reading this latest preprint version Abstract Rationale: Sternal cleft is a rare congenital chest wall defect resulting from failed fusion of the sternal bars during embryogenesis. Primary closure is often feasible in the neonatal period due to thoracic wall compliance, but delayed presentations require complex reconstruction using autologous tissues, muscle flaps, and/or biomaterials [ 1 – 5 ]. Patient concerns: A two-year-old male presented with a visible anterior chest wall defect and progressive respiratory distress. Diagnoses: Physical examination revealed an isolated superior sternal cleft with visible cardiac pulsations beneath the skin. Three-dimensional computed tomography (3D-CT) confirmed the defect dimensions and sternal configuration. Interventions: A patient-specific biodegradable scaffold composed of polycaprolactone (PCL) + hyaluronic acid + β-tricalcium phosphate (β-TCP) was designed using CAD-CAM workflows and produced with 3D printing. The scaffold was fixed to the sternal periosteum with non-absorbable sutures and reinforced with bilateral pectoralis major muscle flaps. Outcomes: No intraoperative complications occurred. The patient was extubated at 12 hours, monitored in the intensive care unit for 2 days, and discharged on postoperative day 7. At the 1- and 3-month follow-ups, respiratory symptoms had resolved; chest wall stability and cosmetic appearance were satisfactory; and imaging confirmed implant stability. Lessons: Patient-specific 3D-printed biodegradable implants can provide a safe and anatomically conforming option for pediatric sternal cleft repair when primary closure is not feasible [ 3 – 5 , 8 – 9 ]. Sternal cleft 3D-printed implant Polycaprolactone (PCL) Congenital chest wall anomaly Biomaterial-based reconstruction Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction Sternal cleft (SC) is a rare congenital anomaly caused by failure of midline fusion of the sternal bars during embryogenesis, accounting for only a small fraction of chest wall defects [ 1 ]. It can be classified as complete or partial, with the superior partial type being the most common and the inferior partial type the rarest [ 2 ]. After birth, paradoxical respiratory motion and mediastinal exposure covered only by thin skin pose significant cardiopulmonary risks [ 1 ]. While primary closure is feasible in the neonatal period due to chest wall compliance, reconstruction becomes more complex in older infants and children due to increasing rigidity and defect width [ 3 , 4 ]. In such cases, autologous costal/cartilaginous grafts, muscle flaps, and synthetic or biomaterial-based prostheses may be required [ 2 – 5 ]. Systematic reviews and institutional experiences emphasize that surgical strategy should be individualized based on age, morphology of the defect, and associated anomalies [ 3 – 5 ]. In recent years, 3D imaging, CAD-CAM design, and patient-specific implant technology have been increasingly applied in large or irregular defects, with potential advantages of improving anatomical conformity, reducing operative time, and enhancing cosmetic outcomes. Composites such as polycaprolactone (PCL) + hyaluronic acid + β-TCP have gained attention for their biocompatibility, fibro-osseous integration potential, and gradual biodegradation, which may support adaptation to growth in pediatric patients [ 8 , 9 ]. Case Report A two-year-old male presented with a midline anterior chest wall defect present since birth and progressive respiratory distress exacerbated during exertion. Perinatal history was unremarkable, with no reported prenatal abnormalities. The family reported visible chest wall retractions and cardiac pulsations during crying episode (Fig. 1) . On examination, an isolated superior sternal cleft measuring approximately 3 cm was identified, with intact overlying skin and visible cardiac pulsations. There were no additional cutaneous lesions. Transthoracic echocardiography demonstrated normal intracardiac anatomy, and abdominal ultrasonography revealed no anomalies. No syndromic features or systemic malformations were noted. Three-dimensional CT provided detailed evaluation of the defect length, width, and sternal configuration. Based on these data, a patient-specific scaffold was designed with CAD-CAM technology and fabricated using 3D printing from a PCL + hyaluronic acid + β-TCP composite. The material was selected for its biocompatibility and ability to support fibro-osseous integration (Fig. 2) . Under general anesthesia in the supine position, an upper midline incision was performed. The sternal periosteum along the defect margins was carefully exposed. The custom scaffold was seated within the defect and secured with non-absorbable sutures to the periosteum, restoring chest wall contour and rigidity. Bilateral pectoralis major flaps were mobilized and advanced over the implant, providing additional soft tissue coverage and reinforcement (Fig. 3–5) . Operative time was 120 minutes. No intraoperative complications occurred. The patient was extubated 12 hours postoperatively and monitored in the intensive care unit for 2 days with stable hemodynamics. No re-intervention was required. During ward follow-up, no wound infection, seroma, or implant-related complications occurred. Oral intake began on postoperative day 2, respiratory distress resolved, and mobilization was achieved. The patient was discharged on postoperative day 7. At the 1-month follow-up, the patient was asymptomatic, with a well-healed incision and stable chest wall; the implant was not palpable, and imaging confirmed stable positioning. At 3 months, pulmonary function was age-appropriate, exertional retractions had resolved, and the family reported high cosmetic satisfaction. Radiological assessment demonstrated perifocal fibrosis and progressive tissue integration (Fig. 6) . Discussion Primary closure in the neonatal period is considered ideal for SC due to reduced tissue tension and thoracic wall pliability [ 3 ]. In older infants and children, increasing rigidity and wider defects necessitate more complex reconstruction strategies, including autologous costal or cartilaginous grafts, muscle flaps, and supportive prostheses [ 2 – 5 ]. Meta-analyses and reviews emphasize individualized strategies according to patient age, defect morphology, and associated anomalies [ 3 , 4 ]. Institutional series similarly report that small defects may be closed primarily, while larger gaps benefit from chondrotomies and supportive materials [ 5 ]. In this case, the patient-specific 3D-printed biodegradable scaffold provided excellent conformity to the defect, reduced dead space, and offered secure fixation points. The PCL + hyaluronic acid + β-TCP composite demonstrated favorable biocompatibility, gradual degradation, and potential compatibility with chest wall growth [ 8 , 9 ]. Coverage with vascularized pectoralis major flaps further enhanced stability and reduced infection risk. Reports in the literature describe successful reconstructions using patient-specific implants (e.g., PEEK or biodegradable composites) when primary closure was not feasible [ 8 ]. Clinical applications of PCL/β-TCP implants in cranio-maxillofacial and orthopedic reconstructions also support their safe use and potential translatability to pediatric chest wall reconstruction [ 8 , 9 ]. Nevertheless, long-term outcomes in growing children remain limited, and ongoing surveillance for remodeling dynamics and rare complications such as infection, displacement, or mismatch between degradation and tissue formation is warranted. In conclusion, the combination of patient-specific 3D-printed biodegradable scaffolds and muscle flaps may provide a safe and effective solution for pediatric SC repair when primary closure is not feasible. Long-term follow-up will clarify the adaptation of these implants to chest wall growth and their durability. Patient Perspective The family expressed satisfaction with the resolution of respiratory symptoms and the cosmetic appearance following surgery. Declarations Informed Consent Written informed consent was obtained from the patient’s legal guardians for publication of this case and accompanying images. Ethical Approval According to institutional policy, single-patient case reports do not require IRB approval. All procedures complied with the Declaration of Helsinki. Conflicts of Interest The authors declare no conflicts of interest. Funding No external funding was received. Author Contribution H.K.E.: Surgery, concept, surgery, data curation, writing – original draft.M.Y.: Surgery, concept, methodology, supervision, critical review.M.O.Ö.: Surgery, critical review.All authors approved the final manuscript. Data Availability All relevant data are included in this article. Additional information is available from the corresponding author upon reasonable request. References StatPearls. Chest Wall Deformities. Treasure Island (FL): StatPearls Publishing; 2023. Guo H, et al. Reconstruction of congenital sternal clefts: Surgical experience and literature review. J Pediatr Surg. 2017;52(12):2100–6. Singh A, et al. Congenital sternal cleft repair: A systematic review and meta-analysis. Ann Plast Surg. 2021;87(5):507–15. Petropoulos AS, et al. Sternal cleft: New options for reconstruction. Pediatr Surg Int. 2024;40(3):315–23. Aksoy B, et al. Sternal cleft repair: Single-institution case series. Turk J Thorac Cardiovasc Surg. 2022;30(2):145–52. Yilmaz M, et al. Isolated superior sternal cleft in a neonate: Case report and literature review. Am J Case Rep. 2022;23:e936542. Ali M, et al. Neonatal sternal cleft: Report of two cases and review of management options. Cureus. 2024;16(2):e51234. Rossi G, et al. Complete sternal cleft repair using a 3D-printed PEEK implant with concomitant cardiac surgery. J Cardiothorac Surg. 2023;18(1):224. Jeong WS, et al. Clinical application of 3D-printed patient-specific PCL/β-TCP scaffold for maxillary reconstruction. Polym (Basel). 2022;14(4):740. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 21 Apr, 2026 Read the published version in Journal of Cardiothoracic Surgery → Version 1 posted Editorial decision: Revision requested 25 Jan, 2026 Reviews received at journal 15 Jan, 2026 Reviews received at journal 10 Jan, 2026 Reviews received at journal 08 Jan, 2026 Reviewers agreed at journal 08 Jan, 2026 Reviewers agreed at journal 08 Jan, 2026 Reviewers agreed at journal 05 Jan, 2026 Reviews received at journal 05 Jan, 2026 Reviewers agreed at journal 05 Jan, 2026 Reviewers agreed at journal 04 Jan, 2026 Reviewers invited by journal 03 Jan, 2026 Editor assigned by journal 08 Oct, 2025 Submission checks completed at journal 08 Oct, 2025 First submitted to journal 02 Oct, 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. 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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-7765634","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":526316444,"identity":"808b8246-51be-4a76-a5b4-935b64362845","order_by":0,"name":"Hayrünisa Kahraman 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1","display":"","copyAsset":false,"role":"figure","size":52072,"visible":true,"origin":"","legend":"\u003cp\u003ePreoperative clinical appearance of the patient showing a visible superior sternal \u003cstrong\u003ecleft with intact overlying skin and visible cardiac pulsations.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7765634/v1/41a0b1e7e35731b83c3cb101.jpg"},{"id":93343190,"identity":"6800e9ce-69aa-4eb9-a828-0e3f677b3477","added_by":"auto","created_at":"2025-10-12 14:49:49","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":18746,"visible":true,"origin":"","legend":"\u003cp\u003eThree-dimensional reconstruction of the thoracic cage demonstrating the patient-specific 3D-printed biodegradable scaffold designed to restore continuity of the superior sternal cleft and conform anatomically to the defect.\u003c/p\u003e","description":"","filename":"Figure2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7765634/v1/176242a9d5052022f2369f52.jpeg"},{"id":93342102,"identity":"aa3eee8c-89b9-44b1-ae19-cb3668c95d78","added_by":"auto","created_at":"2025-10-12 14:41:49","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":390179,"visible":true,"origin":"","legend":"\u003cp\u003eIntraoperative exposure of the sternal cleft margins following midline incision; the defect edges and periosteum are prepared for scaffold placement.\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-7765634/v1/44692885b09a4748b513ab02.png"},{"id":93343193,"identity":"769b40ee-1328-460d-8db4-8675df87f502","added_by":"auto","created_at":"2025-10-12 14:49:49","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":715329,"visible":true,"origin":"","legend":"\u003cp\u003eFixation of the patient-specific 3D-printed polycaprolactone (PCL) + hyaluronic acid + β-tricalcium phosphate (β-TCP) scaffold to the sternal periosteum with non-absorbable sutures.\u003c/p\u003e","description":"","filename":"Figure4.png","url":"https://assets-eu.researchsquare.com/files/rs-7765634/v1/a6bd51dced47acc52d7be45c.png"},{"id":93343194,"identity":"7c0f5da8-70a4-4b1a-900d-fd8ed6b4092d","added_by":"auto","created_at":"2025-10-12 14:49:49","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":408320,"visible":true,"origin":"","legend":"\u003cp\u003eBilateral pectoralis major muscle flaps are mobilized and advanced over the scaffold to provide vascularized coverage and reinforcement.\u003c/p\u003e","description":"","filename":"Figure5.png","url":"https://assets-eu.researchsquare.com/files/rs-7765634/v1/44665d323091ac29281124f7.png"},{"id":93343196,"identity":"a5420f79-26ba-4cb2-98de-9e24ce77345d","added_by":"auto","created_at":"2025-10-12 14:49:49","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":179522,"visible":true,"origin":"","legend":"\u003cp\u003ePostoperative clinical appearance at follow-up showing a well-healed incision line, stable chest wall, and satisfactory cosmetic outcome.\u003c/p\u003e","description":"","filename":"Figure6.png","url":"https://assets-eu.researchsquare.com/files/rs-7765634/v1/1f3dd289e1b4f85ab9b4d72e.png"},{"id":107929518,"identity":"a6127a71-bc5b-4da9-bd05-05ebcd45246b","added_by":"auto","created_at":"2026-04-27 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It can be classified as complete or partial, with the superior partial type being the most common and the inferior partial type the rarest [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. After birth, paradoxical respiratory motion and mediastinal exposure covered only by thin skin pose significant cardiopulmonary risks [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eWhile primary closure is feasible in the neonatal period due to chest wall compliance, reconstruction becomes more complex in older infants and children due to increasing rigidity and defect width [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. In such cases, autologous costal/cartilaginous grafts, muscle flaps, and synthetic or biomaterial-based prostheses may be required [\u003cspan additionalcitationids=\"CR3 CR4\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Systematic reviews and institutional experiences emphasize that surgical strategy should be individualized based on age, morphology of the defect, and associated anomalies [\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn recent years, 3D imaging, CAD-CAM design, and patient-specific implant technology have been increasingly applied in large or irregular defects, with potential advantages of improving anatomical conformity, reducing operative time, and enhancing cosmetic outcomes. Composites such as polycaprolactone (PCL)\u0026thinsp;+\u0026thinsp;hyaluronic acid\u0026thinsp;+\u0026thinsp;β-TCP have gained attention for their biocompatibility, fibro-osseous integration potential, and gradual biodegradation, which may support adaptation to growth in pediatric patients [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e"},{"header":"Case Report","content":"\u003cp\u003eA two-year-old male presented with a midline anterior chest wall defect present since birth and progressive respiratory distress exacerbated during exertion. Perinatal history was unremarkable, with no reported prenatal abnormalities. The family reported visible chest wall retractions and cardiac pulsations during crying episode \u003cb\u003e(Fig.\u0026nbsp;1)\u003c/b\u003e.\u003c/p\u003e\u003cp\u003eOn examination, an isolated superior sternal cleft measuring approximately 3 cm was identified, with intact overlying skin and visible cardiac pulsations. There were no additional cutaneous lesions. Transthoracic echocardiography demonstrated normal intracardiac anatomy, and abdominal ultrasonography revealed no anomalies. No syndromic features or systemic malformations were noted.\u003c/p\u003e\u003cp\u003eThree-dimensional CT provided detailed evaluation of the defect length, width, and sternal configuration. Based on these data, a patient-specific scaffold was designed with CAD-CAM technology and fabricated using 3D printing from a PCL\u0026thinsp;+\u0026thinsp;hyaluronic acid\u0026thinsp;+\u0026thinsp;β-TCP composite. The material was selected for its biocompatibility and ability to support fibro-osseous integration \u003cb\u003e(Fig.\u0026nbsp;2)\u003c/b\u003e.\u003c/p\u003e\u003cp\u003eUnder general anesthesia in the supine position, an upper midline incision was performed. The sternal periosteum along the defect margins was carefully exposed. The custom scaffold was seated within the defect and secured with non-absorbable sutures to the periosteum, restoring chest wall contour and rigidity. Bilateral pectoralis major flaps were mobilized and advanced over the implant, providing additional soft tissue coverage and reinforcement \u003cb\u003e(Fig.\u0026nbsp;3\u0026ndash;5)\u003c/b\u003e.\u003c/p\u003e\u003cp\u003eOperative time was 120 minutes. No intraoperative complications occurred. The patient was extubated 12 hours postoperatively and monitored in the intensive care unit for 2 days with stable hemodynamics. No re-intervention was required. During ward follow-up, no wound infection, seroma, or implant-related complications occurred. Oral intake began on postoperative day 2, respiratory distress resolved, and mobilization was achieved. The patient was discharged on postoperative day 7.\u003c/p\u003e\u003cp\u003eAt the 1-month follow-up, the patient was asymptomatic, with a well-healed incision and stable chest wall; the implant was not palpable, and imaging confirmed stable positioning. At 3 months, pulmonary function was age-appropriate, exertional retractions had resolved, and the family reported high cosmetic satisfaction. Radiological assessment demonstrated perifocal fibrosis and progressive tissue integration \u003cb\u003e(Fig.\u0026nbsp;6)\u003c/b\u003e.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003ePrimary closure in the neonatal period is considered ideal for SC due to reduced tissue tension and thoracic wall pliability [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. In older infants and children, increasing rigidity and wider defects necessitate more complex reconstruction strategies, including autologous costal or cartilaginous grafts, muscle flaps, and supportive prostheses [\u003cspan additionalcitationids=\"CR3 CR4\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Meta-analyses and reviews emphasize individualized strategies according to patient age, defect morphology, and associated anomalies [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Institutional series similarly report that small defects may be closed primarily, while larger gaps benefit from chondrotomies and supportive materials [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn this case, the patient-specific 3D-printed biodegradable scaffold provided excellent conformity to the defect, reduced dead space, and offered secure fixation points. The PCL\u0026thinsp;+\u0026thinsp;hyaluronic acid\u0026thinsp;+\u0026thinsp;β-TCP composite demonstrated favorable biocompatibility, gradual degradation, and potential compatibility with chest wall growth [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Coverage with vascularized pectoralis major flaps further enhanced stability and reduced infection risk.\u003c/p\u003e\u003cp\u003eReports in the literature describe successful reconstructions using patient-specific implants (e.g., PEEK or biodegradable composites) when primary closure was not feasible [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Clinical applications of PCL/β-TCP implants in cranio-maxillofacial and orthopedic reconstructions also support their safe use and potential translatability to pediatric chest wall reconstruction [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Nevertheless, long-term outcomes in growing children remain limited, and ongoing surveillance for remodeling dynamics and rare complications such as infection, displacement, or mismatch between degradation and tissue formation is warranted.\u003c/p\u003e\u003cp\u003eIn conclusion, the combination of patient-specific 3D-printed biodegradable scaffolds and muscle flaps may provide a safe and effective solution for pediatric SC repair when primary closure is not feasible. Long-term follow-up will clarify the adaptation of these implants to chest wall growth and their durability.\u003c/p\u003e\n\u003ch3\u003ePatient Perspective\u003c/h3\u003e\n\u003cp\u003eThe family expressed satisfaction with the resolution of respiratory symptoms and the cosmetic appearance following surgery.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003ch2\u003eInformed Consent\u003c/h2\u003e\u003cp\u003eWritten informed consent was obtained from the patient\u0026rsquo;s legal guardians for publication of this case and accompanying images.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eEthical Approval\u003c/strong\u003e\u003cp\u003eAccording to institutional policy, single-patient case reports do not require IRB approval. All procedures complied with the Declaration of Helsinki.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003ch2\u003eConflicts of Interest\u003c/h2\u003e\u003cp\u003eThe authors declare no conflicts of interest.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e\u003cp\u003eNo external funding was received.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eH.K.E.: Surgery, concept, surgery, data curation, writing \u0026ndash; original draft.M.Y.: Surgery, concept, methodology, supervision, critical review.M.O.\u0026Ouml;.: Surgery, critical review.All authors approved the final manuscript.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eAll relevant data are included in this article. Additional information is available from the corresponding author upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eStatPearls. Chest Wall Deformities. Treasure Island (FL): StatPearls Publishing; 2023.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGuo H, et al. Reconstruction of congenital sternal clefts: Surgical experience and literature review. J Pediatr Surg. 2017;52(12):2100\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSingh A, et al. Congenital sternal cleft repair: A systematic review and meta-analysis. Ann Plast Surg. 2021;87(5):507\u0026ndash;15.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePetropoulos AS, et al. Sternal cleft: New options for reconstruction. Pediatr Surg Int. 2024;40(3):315\u0026ndash;23.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAksoy B, et al. Sternal cleft repair: Single-institution case series. Turk J Thorac Cardiovasc Surg. 2022;30(2):145\u0026ndash;52.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYilmaz M, et al. Isolated superior sternal cleft in a neonate: Case report and literature review. Am J Case Rep. 2022;23:e936542.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAli M, et al. Neonatal sternal cleft: Report of two cases and review of management options. Cureus. 2024;16(2):e51234.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRossi G, et al. Complete sternal cleft repair using a 3D-printed PEEK implant with concomitant cardiac surgery. J Cardiothorac Surg. 2023;18(1):224.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eJeong WS, et al. Clinical application of 3D-printed patient-specific PCL/β-TCP scaffold for maxillary reconstruction. Polym (Basel). 2022;14(4):740.\u003c/span\u003e\u003c/li\u003e\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-cardiothoracic-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jcts","sideBox":"Learn more about [Journal of Cardiothoracic Surgery](http://cardiothoracicsurgery.biomedcentral.com)","snPcode":"13019","submissionUrl":"https://submission.nature.com/new-submission/13019/3","title":"Journal of Cardiothoracic Surgery","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Sternal cleft, 3D-printed implant, Polycaprolactone (PCL), Congenital chest wall anomaly, Biomaterial-based reconstruction","lastPublishedDoi":"10.21203/rs.3.rs-7765634/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7765634/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eRationale:\u003c/h2\u003e\u003cp\u003eSternal cleft is a rare congenital chest wall defect resulting from failed fusion of the sternal bars during embryogenesis. Primary closure is often feasible in the neonatal period due to thoracic wall compliance, but delayed presentations require complex reconstruction using autologous tissues, muscle flaps, and/or biomaterials [\u003cspan additionalcitationids=\"CR2 CR3 CR4\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e\u003ch2\u003ePatient concerns:\u003c/h2\u003e\u003cp\u003eA two-year-old male presented with a visible anterior chest wall defect and progressive respiratory distress.\u003c/p\u003e\u003ch2\u003eDiagnoses:\u003c/h2\u003e\u003cp\u003ePhysical examination revealed an isolated superior sternal cleft with visible cardiac pulsations beneath the skin. Three-dimensional computed tomography (3D-CT) confirmed the defect dimensions and sternal configuration.\u003c/p\u003e\u003ch2\u003eInterventions:\u003c/h2\u003e\u003cp\u003eA patient-specific biodegradable scaffold composed of polycaprolactone (PCL)\u0026thinsp;+\u0026thinsp;hyaluronic acid\u0026thinsp;+\u0026thinsp;β-tricalcium phosphate (β-TCP) was designed using CAD-CAM workflows and produced with 3D printing. The scaffold was fixed to the sternal periosteum with non-absorbable sutures and reinforced with bilateral pectoralis major muscle flaps.\u003c/p\u003e\u003ch2\u003eOutcomes:\u003c/h2\u003e\u003cp\u003eNo intraoperative complications occurred. The patient was extubated at 12 hours, monitored in the intensive care unit for 2 days, and discharged on postoperative day 7. At the 1- and 3-month follow-ups, respiratory symptoms had resolved; chest wall stability and cosmetic appearance were satisfactory; and imaging confirmed implant stability.\u003c/p\u003e\u003ch2\u003eLessons:\u003c/h2\u003e\u003cp\u003ePatient-specific 3D-printed biodegradable implants can provide a safe and anatomically conforming option for pediatric sternal cleft repair when primary closure is not feasible [\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e","manuscriptTitle":"Patient-Specific 3D-Printed Scaffold for Pediatric Superior Sternal Cleft Repair","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-12 14:41:44","doi":"10.21203/rs.3.rs-7765634/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-01-25T08:16:35+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-15T12:25:29+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-11T00:50:01+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-08T10:36:15+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"140827535428197990211115727340375340538","date":"2026-01-08T10:20:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"11174060015603082146702166955627770191","date":"2026-01-08T10:04:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"36157648838439512535557424824800716328","date":"2026-01-05T19:25:19+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-05T13:12:21+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"104426620760363626100258969917729476010","date":"2026-01-05T09:49:51+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"292150189875043499793449320890309574078","date":"2026-01-04T12:35:38+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-03T09:34:03+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-08T06:07:53+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-08T06:06:27+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Cardiothoracic Surgery","date":"2025-10-02T10:09:00+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-cardiothoracic-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jcts","sideBox":"Learn more about [Journal of Cardiothoracic Surgery](http://cardiothoracicsurgery.biomedcentral.com)","snPcode":"13019","submissionUrl":"https://submission.nature.com/new-submission/13019/3","title":"Journal of Cardiothoracic Surgery","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"d0d049b4-8c79-4207-b5b3-d4e6bc15eba1","owner":[],"postedDate":"October 12th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-04-27T16:17:21+00:00","versionOfRecord":{"articleIdentity":"rs-7765634","link":"https://doi.org/10.1186/s13019-026-04067-z","journal":{"identity":"journal-of-cardiothoracic-surgery","isVorOnly":false,"title":"Journal of Cardiothoracic Surgery"},"publishedOn":"2026-04-21 15:57:41","publishedOnDateReadable":"April 21st, 2026"},"versionCreatedAt":"2025-10-12 14:41:44","video":"","vorDoi":"10.1186/s13019-026-04067-z","vorDoiUrl":"https://doi.org/10.1186/s13019-026-04067-z","workflowStages":[]},"version":"v1","identity":"rs-7765634","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7765634","identity":"rs-7765634","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}