Novel Sternoclavicular Hook Plate for Traumatic Dislocations: Functional Outcomes and Complications

Novel Sternoclavicular Hook Plate for Traumatic Dislocations: Functional Outcomes and Complications | 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 Novel Sternoclavicular Hook Plate for Traumatic Dislocations: Functional Outcomes and Complications LI Sheng, Yaqing Wu, Jie Feng, Xiaoyong Sheng This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6338049/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objective: This study evaluates the efficacy and complications associated with sternoclavicular（SC）hook plates in treating traumatic sternoclavicular joint (SCJ) dislocations. Methods: A retrospectively analyzed on patients who underwent SC hook plates forfixation SCJ dislocations, focusing on hardware-related complications such as plate breakages and fixation failures. Clinical outcomes, functional recovery, and complications were assessed. Postoperative imaging, including X-raysand CT scans, was used to evaluate joint reduction and hardware integrity, Functional out comes were measured using the Constant Shoulder Score (CSS) and Visual Analog Scale (VAS) for pain. Results: SC hook plates effectively stabilized the joint and significantly improved function, as demonstrated by an increase in the mean CSS scores from 36.4 preoperatively to 86.6 postoperatively, and a decrease in VAS scores from 7.2 to 1.6. However, 4 patients (8.7%) experienced plate breakages without redislocation, and 1 patient (2%) experienced fixation failure, requiring revision surgeries. No major neurovascular complications were observed. Conclusions: While SC hook plates provide effective stabilization for SCJ dislocations, they are associated with hardware-related complications, including plate breakages and fixation failures. Improvements in implant design, patient selection are necessary to address these issues and improve long-term outcomes. Future research should focus on the developing of more ergonomic implants and exploration of alternative treatment options. Sternoclavicular Hook Sternoclavicular joint Dislocation Hardware Failure Joint Stabilization Postoperative Outcomes Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Sternoclavicular joint (SCJ) dislocations, although uncommon, present significant challenges in trauma surgery due to the joint's crucial role in shoulder stability and its proximity to vital structures [1] . These dislocations are classified as anterior, which are more but less severe, and posterior, which are rarer yet potentially life-threatening due to the risk of compressing on the trachea, blood vessels, or esophagus [2] . Treatment options for SCJ dislocations range from conservative methods, such as closed reduction and immobilization for stable anterior dislocations to surgical interventions such as open reduction and internal fixation (ORIF) or ligament reconstruction for posterior dislocations or cases of persistent instability [3-5] . The introduction of SC hook plates has advanced the surgical treatment by providing enhanced mechanical stability, particularly in traumatic cases, and allowing for early mobilization [6-8] . Despite these benefits, the technique may be associated with complications, including hardware failure, plate loosening, and functional impairments, highlighting the need for further refinement the procedure and long-term outcome evaluation. Therefore, there is a pressing need for a comprehensive assessment of the risks and benefits of using of hook plates in treating SCJ dislocations. This study aims to fill this gap by thoroughly examining the challenges and complications associated with SC hook plate use. The primary objective is to systematically evaluate the frequency, types, and consequences of hardware and functional complications, while also offering recommendations for optimizing surgical techniques and implant design to improve patient outcomes. Methodology 1.1 Study Design This single-institution retrospective cohort study consecutively analyzed 46 patients undergoing open reduction and internal fixation with SC hook plates for acute (within 3 weeks of trauma) SCJ dislocations at our tertiary care center between January 2015 and December 2022. Inclusion criteria mandated one of the following: had failed manual reduction, experienced redislocation after repositioning or could not tolerate prolonged joint immobilization, thus requiring surgical intervention. Exclusion criteria encompassed chronic SCJ injuries, those managed conservatively, and individuals with underlying conditions that could affect bone healing. 1.2 Surgical Technique The procedure began with the administration of general anesthesia and patient positioning in the supine orientation. An inverted "7"-shaped incision was made along the upper midline of the sternum. The periosteum on the affected side of the sternum, along with attachment of the sternocleidomastoid muscle, were carefully detached using a periosteal dissector. Sternal Tunnel Preparation: A custom-designed drill guide (Zhejiang CANWELL Medical Equipment Co.) was aligned at the sternal midline, A 4.2-mm cannulated drill bit was advanced under fluoroscopic guidance to create a bicortical tunnel, with depth verification (average 20–25 mm) to prevent mediastinal penetration. A curved metallic retractor (sternum pulling guide) was inserted posterior to the sternum during drilling to protect vital structures. Joint Reduction and Fixation: Manual reduction of the SCJ was achieved by applying downward traction on the proximal clavicle while stabilizing the sternum. A cable introducer (flexible stainless-steel wire with a looped tip) was passed through the sternal tunnel, secured to the hook plate’s cable head, and tensioned to engage the hook within the tunnel. The plate was contoured to the clavicle’s superior surface, and three 3.5-mm cortical screws (length 20–25 mm) were inserted after drilling and tapping. Intraoperative fluoroscopy confirmed reduction quality and hardware positioning. If residual instability was detected (≥2 mm translation on stress views), a shim washer (1–2 mm thickness) was placed between the plate and clavicle to augment compression. The difference in the surgical method of posterior dislocation lies in the need for emergency surgical treatment. During the operation, the posterior dislocated clavicular head needs to be carefully reset from the sternum to the normal position with instruments (Fig.1, 2). Closure and Reinforcement: The joint capsule was reapproximated with non-absorbable sutures (Ethibond 2-0), and the sternocleidomastoid muscle was reattached to its sternal origin using interrupted sutures. Subcutaneous tissues were closed with absorbable sutures, and the skin was approximated with staples or running nylon sutures. Intraoperative Safety Protocols: Real-time fluoroscopy was used to confirm tunnel placement, hardware alignment, and joint reduction. The posterior sternal retractor was maintained throughout drilling and cable passage to prevent mediastinal injury. Post-fixation stability testing included passive range of motion (ROM) to 90° abduction and anterior-posterior stress testing under fluoroscopy. 1.3 Postoperative Management: In accordance with standardized postoperative care, patients received a triangular shoulder sling for immobilization commencing 48 hours postoperatively. A structured rehabilitation protocol was implemented, comprising graduated functional exercises initiated at 14 days, with progressive restoration of shoulder abduction and flexion limited to 90° for the initial 6 postoperative weeks. Vigorous physical activities were restricted for an additional 3 months to ensure soft tissue maturation. Elective removal of the SC hook plate was generally scheduled between 6 and 12 months postoperatively, contingent upon radiographic evidence of osseous union and clinical stability. A comprehensive surveillance strategy was adopted, incorporating immediate postoperative radiographic assessment (within 24 hours) via anteroposterior and axial radiographs complemented by computed tomography (CT) to confirm anatomic reduction, hardware positioning. Serial follow-up imaging included biplanar radiographs at 1, 3, 6, and 12 months, with adjunctive CT scans at 6 and 12 months for patients with post-traumatic SCJ instability. Radiologic evaluations focused on joint congruency, hardware integrity (including screw migration or cortical penetration), and osseous integration. All imaging studies were independently interpreted by two fellowship-trained musculoskeletal radiologists, with interobserver discrepancies resolved via consensus conference. Clinical assessments were conducted at standardized intervals (2 weeks, 1, 3, 6, and 12 months) utilizing validated metrics, including the Constant-Murley Shoulder Score (CSS) and Visual Analog Scale (VAS) for pain. Longitudinal surveillance beyond 24 months incorporated annual clinical evaluations and telemedicine follow-ups to monitor functional outcomes and identify delayed complications. 1.4 Data Collection A comprehensive surveillance strategy was adopted, incorporating immediate postoperative radiographic assessment (within 24 hours) via anteroposterior and axial radiographs complemented by computed tomography (CT) to confirm anatomic reduction, hardware positioning. Serial follow-up imaging included biplanar radiographs at 1, 3, 6, and 12 months, with adjunctive CT scans at 6 and 12 months for patients with post-traumatic SCJ instability. Radiologic evaluations focused on joint congruency, hardware integrity (including screw migration or cortical penetration), and osseous integration. All imaging studies were independently interpreted by two fellowship-trained musculoskeletal radiologists, with interobserver discrepancies resolved via consensus conference. Clinical assessments were conducted at standardized intervals (2 weeks, 1, 3, 6, and 12 months) utilizing validated metrics, including the Constant-Murley Shoulder Score (CSS) and Visual Analog Scale (VAS) for pain. Longitudinal surveillance beyond 24 months incorporated annual clinical evaluations and telemedicine follow-ups to monitor functional outcomes and identify delayed complications. 1.5 Statistical Analysis A comparative analysis between preoperative and postoperative outcomes was conducted using statistical tests, such as paired t-tests, to assess changes in joint function and pain levels, contributing to a comprehensive evaluation of the effectiveness of hook plates in improving patient recovery. Results 2.1 Patient Demographics and Clinical Data The study cohort consisted of 46 individuals who underwent treatment with SC hook plates for SCJ dislocations between 2015 and 2022. The demographic analysis revealed a mean age of 49.3 years (range: 28 to 73 years), with a predominant representation of male patients (44 males, 2 females). High-energy trauma, primarily resulting from traffic accidents (44 cases) and sports injuries (2 cases), was the most common mechanism of injury. 42 cases were classified as anterior dislocations, and 4 cases as posterior dislocations. This classification is important due to the increased risks associated with posterior dislocations, highlighting the significance of using hook plates in these cases (Table 1). 2.2 Surgical Outcomes The average operative duration for the 46 patients undergoing SC hook plate fixation varied between 55 and 95 minutes, with a mean of 65.2 ± 8.4 minutes. Notably, there were no instances of nerve or vascular injuries reported as intraoperative complications, no patients experienced localized skin complications, including erythema, ulceration, or device-related pressure injuries, attributable to hardware prominence. and the average blood loss during surgery was minimal at 46.2 ± 14.6 mL. Preoperatively, the mean CSS was 36.4 ± 4.8 points (range: 28-46 points). At the final follow-up, the postoperative mean CSS score significantly improved to 86.6 ± 6.2 points (range: 80-92) at the final follow-up, with a p-value of <0.05, indicating a statistically significant difference. Additionally, the mean VAS score improvement from 7.2 ± 1.4 (range: 5-8) preoperatively to 1.6 ± 0.4 (range: 0-3) at the final follow-up, a p-value of <0.05, denoting a statistically significant difference. Postoperative radiographic assessments, including X-rays and CT scans, consistently demonstrated successful joint repositioning in all cases, with the hook plates effectively maintaining proper SCJ alignment. Throughout the follow-up period, hardware integrity remained intact, with no instances of significant hardware loosening or displacement immediately post-surgery, However, a few cases of hardware-related complications emerged during recovery. Scheduled removal at 6–12 months is safe and recommended, with intraoperative stability testing to confirm adequate healing before implant extraction. 2.3 Complications and Hardware Issues Following the use of SC hook plates, the study identified several hardware-related complications. Notably, a 66-year-old male patient (2%) experienced fixation failure and redislocation within 10 days post-surgery, necessitating revision surgery (Fig.3). Additionally, during follow-ups, plate breakages were observed in 4 patients (8.7%) (Fig.4), although these occurrences did not result in redislocation or require immediate revision surgeries. Discussion This study validates the biomechanical efficacy of SC hook plates in achieving joint reduction and functional restoration for SCJ dislocations. Radiographic evaluation confirmed successful stabilization in 98% of cases, with postoperative CSS improving significantly from 36.4 ± 4.8 preoperatively to 86.6 ± 6.2 at final follow-up (p < 0.05), reflecting substantial recovery of shoulder kinematics. Concurrent reductions in VAS scores (7.2 ± 1.4 preoperatively to 1.6 ± 0.4 postoperatively, p < 0.05) corroborate effective pain alleviation, critical for early mobilization and rehabilitation compliance. However, these functional gains are tempered by hardware-related complications, including asymptomatic plate breakage (8.7%) and fixation failure necessitating revision surgery (2%). Notably, complications disproportionately occurred in patients with osteoporosis or high-energy trauma, suggesting a mechanistic interplay between bone quality, trauma biomechanics, and implant stress distribution. The observed complications align with biomechanical studies identifying stress concentration at the hook-bone interface as a predisposing factor for plate failure [7]. This phenomenon underscores the critical balance between achieving mechanical stability and mitigating long-term implant fatigue, particularly in high-risk cohorts. While the absence of neurovascular injuries and low redislocation rate (2%) demonstrate the technique’s safety profile, the trade-off between immediate stabilization and delayed hardware degradation warrants scrutiny. The low preoperative CSS also reflects the combined impact of SCJ instability, pain-mediated functional impairment, and compensatory shoulder mechanics, emphasizing the urgency of timely intervention to restore global shoulder function. Future investigations should prioritize longitudinal CSS and VAS assessments to elucidate the interplay between hardware integrity, joint stability, and sustained clinical outcomes. Additionally, biomechanical optimization of implant design—such as modifying hook curvature or incorporating locking mechanisms—and extended follow-up protocols are essential to address these risks in complex dislocations or osteoporotic bone. Conservative management (e.g., closed reduction and immobilization) are often preferred for stable anterior dislocations; however, it may fail to provide long-term stability in some cases. This failure can result in chronic instability, a higher risk of redislocation (up to 21–100%) [9] , and poor functional outcomes [10] , including persistent pain, decreased functionality, post-traumatic arthritis, and cosmetic deformities. Moreover, in cases of severe dislocation, conservative treatment often falls short in restoring full joint stability, increasing the likelihood of requiring surgical intervention for better long-term recovery. In contrast, surgical intervention with hook plates provides immediate stability, early mobilization, and significantly lower redislocation rates (2% in our cohort), although it is associated with hardware-related risks. This highlights the importance of individualized treatment plans based on dislocation severity and patient-specific factors. Comparison between SC hook plates and other techniques, such as acromioclavicular (AC) hook plates and ligament repair (using artificial or autologous ligaments), reveals distinct differences. AC hook plates are commonly used for AC joint dislocations due to their robust fixation properties and ability to maintain reduction. Qu et al. [7] reported successful treatment of 10 patients with anterior SCJ dislocation using AC hook plates without complications, with a follow-up of 16.9 months, providing sufficient short-to-medium-term outcomes but lacking the long-term complications observed in this study. Ligament repair, whether using artificial or autologous grafts, takes a more biological approach by relying on the body's natural healing mechanisms. This method typically involves longer recovery periods due to the dependence on ligament healing and carries a heighter risk of redislocation in severe trauma cases compared to the immediate stabilization provided by hook plates. Nevertheless, ligament repair has the advantage of avoiding hardware complications and may be preferable in less severe dislocations, where the risk of hardware failure is minimal [11-14] . Several less invasive techniques, such as Button devices connected to suture and minimally invasive suture fixation, offers a more anatomical approach, particularly for chronic instability or low-demand injuries, However, these techniques requires prolonged rehabilitation and may lack sufficient stability in high-energy trauma [11] . Minimally invasive techniques, such as FiberWire® fixation, avoid hardware-related complications but may be less effective in cases of severe ligamentous disruption or osteoporotic bone [12, 15] . While these methods have the advantage of avoiding hardware issues, they may not be suitable for acute, unstable posterior dislocations or high-demand patients requiring rapid stabilization. The choice of technique should be tailored to injury severity, patient characteristics, and functional demands, underscoring the need for further comparative studies to optimize treatment selection. This study makes a significantly contribution by addressing complications, challenges, and long-term outcomes associated with SC hook plates in treatment of SCJ dislocation, complementing the generally favorable outcomes reported in earlier studies [6-8, 16, 17] ，While past research indicated no complications, wound infections, or plate/screw breakages, this study highlights potential risks, offering a more comprehensive understanding of long-term performance and hardware-related complications in specific patient subsets. By identifying this novel complication, absent in prior studies, this research underscores potential gaps in earlier evaluations, emphasizing the importance of thorough long-term monitoring and hardware performance analysis. This discovery suggests that previous studies may have underestimated certain risks over extended periods or in specific patient groups, contributing to the refinement of clinical practice through rigorous postoperative follow-up and surgical technique adaptation to proactively address future treatment challenges. Furthermore, this finding underscores the ongoing need for plate design innovation and continued research to capture the full spectrum of associated linked with SC hook plates. While the study documented 8.7% plate breakage rate, it is critical to acknowledge the biomechanical challenges inherent in any bridging implant spanning a dynamic joint. Like acromioclavicular (AC) hook plates, which are prone to fatigue failure over time due to cyclic loading at the joint interface, SC hook plates are similarly subjected to repetitive stress from clavicular motion during shoulder activities. This risk is compounded by the SCJ’s unique mobility, which involves translation and rotation during arm movement. Previous studies on AC hook plates report long-term use, underscoring the principle that bridging constructs across articulations may inherently fail due to mechanical fatigue rather than acute overload [18] . Given this biomechanical reality, early implant removal (6–12 months postoperatively) is recommended to mitigate late hardware failure. This aligns with current guidelines for AC hook plates, where removal after 6 months reduces stress shielding and fatigue risks. In our cohort, all plate breakages occurred in patients who retained implants beyond 6 months, suggesting a temporal association with hardware fatigue. While immediate stability is essential for healing, prolonged retention may paradoxically increase failure risk. Future studies should prospectively evaluate outcomes of accelerated implant removal protocols (e.g., 6 months) in low-demand patients versus delayed removal in high-demand individuals. The absence of dislocation following hardware failure suggests that bony and soft-tissue healing may provide sufficient joint stability once implant degradation occurs, underscoring the hook plate’s transient role in maintaining anatomical alignment during the critical healing phase. This biomechanical interplay implies that prolonged implant dependency may be unnecessary in select patients, particularly those at risk of delayed healing (e.g., osteoporosis, smoking), where alternative strategies like ligament reconstruction could mitigate hardware-related morbidity. Surgeons must balance early mobilization benefits against the 8.7% incidence of asymptomatic plate fractures and 2% fixation failures, emphasizing patient education on scheduled explantation to prevent delayed complications. Innovations in biomaterials—such as fatigue-resistant titanium alloys or bioabsorbable implants—may address these limitations while preserving the plate’s capacity to achieve immediate mechanical stability, particularly in complex posterior dislocations near critical neurovascular structures. However, the inclusion of heterogeneous dislocation types (anterior/posterior) introduces confounding variables, as posterior injuries—though numerically fewer—present unique anatomical challenges requiring specialized surgical considerations. The study’s retrospective design and limited posterior dislocation subgroup size (n=4) restrict definitive conclusions about subgroup-specific outcomes, necessitating prospective stratification in future investigations to refine risk-benefit profiles for distinct injury patterns. These findings collectively advance the paradigm of minimally invasive stabilization while highlighting the imperative for continued innovation in implant design and patient-specific surgical planning. SC hook plates are recommended for acute, unstable posterior dislocations requiring immediate stabilization to protect critical structures, high-energy trauma with severe ligamentous disruption, and high-demand patients (e.g., athletes) needing rapid mobilization. Conversely, alternative techniques (e.g., ligament repair, suture fixation) are preferable for stable anterior dislocations, chronic instability without bony involvement, osteoporotic patients at risk of hardware failure, or low-demand individuals tolerant of prolonged rehabilitation. Patient-specific factors—injury severity, bone quality, functional needs, and risk tolerance—should guide treatment selection. Future implant designs should prioritize ergonomic shapes and durable materials to mitigate complications, expanding safe applicability across diverse clinical scenarios. The retrospective study design, small sample size, and limited follow-up duration are notable limitations, reduce the generalizability of findings and prevent a comprehensive assessment of long-term complications. To address these limitations, future research should include larger sample sizes, prospective studies, and extended follow-up periods to further explore the enduring efficacy of the plates. Additionally, recommending enhancements in implant design and surgical techniques is crucial for minimizing risks and ensuring superior outcomes for patients with SCJ dislocation. Conclusion This study affirms the effectiveness of SC hook plates in stabilizing traumatic SCJ dislocations, particularly in cases requiring immediate mechanical stability. However, the observed hardware-related complications, such as fixation failure and plate breakages, highlight the need for ongoing innovation in implant design and surgical techniques. Future research should prioritize the development of more durable implants, comprehensive long-term outcome assessments, and individualized treatment strategies to optimize patient outcomes. Declarations Ethics Approval and Consent to Participate: The study was approved by the Ethics Committee of Taizhou Hospital of Zhejiang Province of Ethics Committee (Approval Number: kL20240919). Informed consent was obtained from all participants prior to inclusion in the study. Consent for Publication: Written informed consent for publication of their clinical details and images was obtained from the parents or legal guardians of the patients. A copy of the consent form is available for review by the Editor of this journal. Availability of Data and Materials: The datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request. Competing Interests: The authors declare that they have no competing interests. Funding: This work was funded by the Enze Medical Center (Group) Scientific Research Fund (19EZC28, 21EZD21). Authors' Contributions: [Li Sheng] designed the study. [Yaiqing Wu, Jie Feng] collected and analyzed the data. [Xiaoyong Sheng] contributed to the writing and editing of the manuscript. All authors read and approved the final manuscript. Acknowledgments: We would like to thank Taizhou Hospital of Zhejiang Province for their assistance and support in this study. References Miniato M. 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S.,Beazley J.,Zywiel M. G., et al. ,Controversies relating to the management of acromioclavicular joint dislocations[J].Bone Joint J,2013,95-b(12):1595-1602 Table Table 1 is available in the Supplementary Files section Additional Declarations No competing interests reported. Supplementary Files table.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6338049","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":441970347,"identity":"b8ae0db2-d410-4558-b627-3f85ab3ad76b","order_by":0,"name":"LI Sheng","email":"","orcid":"","institution":"Hangzhou First People's Hospital","correspondingAuthor":false,"prefix":"","firstName":"LI","middleName":"","lastName":"Sheng","suffix":""},{"id":441970348,"identity":"b163961f-b200-4477-b0bd-fd3c2c799636","order_by":1,"name":"Yaqing Wu","email":"","orcid":"","institution":"Zhejiang Taizhou 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06:06:56","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":21641,"visible":true,"origin":"","legend":"","description":"","filename":"table.docx","url":"https://assets-eu.researchsquare.com/files/rs-6338049/v1/46aef7e097e644e112f4be67.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Novel Sternoclavicular Hook Plate for Traumatic Dislocations: Functional Outcomes and Complications","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSternoclavicular joint (SCJ) dislocations, although uncommon, present\u0026nbsp;significant challenges in trauma surgery due to the joint\u0026apos;s crucial role in shoulder stability and its proximity to vital structures\u003csup\u003e[1]\u003c/sup\u003e. \u0026nbsp;These dislocations are classified\u0026nbsp;as anterior, which are more but less severe, and\u0026nbsp;posterior, which are rarer\u0026nbsp;yet potentially life-threatening due to the risk of compressing on the trachea, blood vessels, or esophagus\u003csup\u003e[2]\u003c/sup\u003e. Treatment options for SCJ dislocations range from conservative methods, such as\u0026nbsp;closed reduction and immobilization for stable anterior dislocations to surgical interventions such as open reduction and internal fixation (ORIF) or ligament reconstruction for posterior dislocations or cases of persistent instability\u003csup\u003e[3-5]\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;The introduction of SC hook plates has advanced the surgical treatment\u0026nbsp;by providing enhanced\u0026nbsp;mechanical stability, particularly in traumatic cases, and allowing for early mobilization\u003csup\u003e[6-8]\u003c/sup\u003e. Despite these benefits, the technique may be associated with complications, including hardware failure, plate loosening, and functional impairments, highlighting\u0026nbsp;the need for further refinement the procedure\u0026nbsp;and long-term outcome\u0026nbsp;evaluation.\u0026nbsp;Therefore, there is a pressing need for a comprehensive assessment of the risks and benefits of using of hook plates in treating SCJ dislocations.\u003c/p\u003e\n\u003cp\u003eThis study aims to fill this gap by thoroughly examining the challenges and complications associated with SC hook plate use. The primary objective is to systematically evaluate the frequency, types, and consequences of hardware and functional complications, while also offering recommendations for optimizing surgical techniques and implant design to improve patient outcomes.\u003c/p\u003e"},{"header":"Methodology","content":"\u003ch3\u003e1.1 Study Design\u003c/h3\u003e\n\u003cp\u003eThis single-institution retrospective cohort study consecutively analyzed 46 patients undergoing open reduction and internal fixation with SC hook plates for acute (within 3 weeks of trauma) SCJ dislocations at our tertiary care center between January 2015 and December 2022. Inclusion criteria mandated one of the following: had failed manual reduction, experienced redislocation after repositioning or could not tolerate prolonged joint immobilization, thus requiring surgical intervention. Exclusion criteria encompassed chronic SCJ injuries, those managed conservatively, and individuals with underlying conditions that could affect bone healing.\u003c/p\u003e\n\u003ch3\u003e1.2 Surgical Technique\u003c/h3\u003e\n\u003cp\u003eThe procedure began with the administration of\u0026nbsp;general anesthesia and patient positioning in the supine orientation. An inverted \u0026quot;7\u0026quot;-shaped incision was made along the upper midline of the sternum. The periosteum on the affected side of the sternum, along with\u0026nbsp;attachment of the sternocleidomastoid muscle, were carefully\u0026nbsp;detached using a periosteal dissector.\u003c/p\u003e\n\u003cp\u003eSternal Tunnel Preparation:\u003c/p\u003e\n\u003cp\u003eA custom-designed drill guide (Zhejiang CANWELL Medical Equipment Co.) was aligned at the sternal midline, A 4.2-mm cannulated drill bit was advanced under fluoroscopic guidance to create a bicortical tunnel, with depth verification (average 20\u0026ndash;25 mm) to prevent mediastinal penetration. A curved metallic retractor (sternum pulling guide) was inserted posterior to the sternum during drilling to protect vital structures.\u003c/p\u003e\n\u003cp\u003eJoint Reduction and Fixation:\u003c/p\u003e\n\u003cp\u003eManual reduction of the SCJ was achieved by applying downward traction on the proximal clavicle while stabilizing the sternum. A cable introducer (flexible stainless-steel wire with a looped tip) was passed through the sternal tunnel, secured to the hook plate\u0026rsquo;s cable head, and tensioned to engage the hook within the tunnel. The plate was contoured to the clavicle\u0026rsquo;s superior surface, and three 3.5-mm cortical screws (length 20\u0026ndash;25 mm) were inserted after drilling and tapping. Intraoperative fluoroscopy confirmed reduction quality and hardware positioning. If residual instability was detected (\u0026ge;2 mm translation on stress views), a shim washer (1\u0026ndash;2 mm thickness) was placed between the plate and clavicle to augment compression.\u0026nbsp;The difference in the surgical method of posterior dislocation lies in the need for emergency surgical treatment. During the operation, the posterior dislocated clavicular head needs to be carefully reset from the sternum to the normal position with instruments (Fig.1, 2).\u003c/p\u003e\n\u003cp\u003eClosure and Reinforcement:\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe joint capsule was reapproximated with non-absorbable sutures (Ethibond 2-0), and the sternocleidomastoid muscle was reattached to its sternal origin using interrupted sutures. Subcutaneous tissues were closed with absorbable sutures, and the skin was approximated with staples or running nylon sutures.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIntraoperative Safety Protocols:\u003c/p\u003e\n\u003cp\u003eReal-time fluoroscopy was used to confirm tunnel placement, hardware alignment, and joint reduction. The posterior sternal retractor was maintained throughout drilling and cable passage to prevent mediastinal injury. Post-fixation stability testing included passive range of motion (ROM) to 90\u0026deg; abduction and anterior-posterior stress testing under fluoroscopy.\u003c/p\u003e\n\u003ch3\u003e1.3 Postoperative Management:\u003c/h3\u003e\n\u003cp\u003eIn accordance with standardized postoperative care, patients received a triangular shoulder sling for immobilization commencing 48 hours postoperatively. A structured rehabilitation protocol was implemented, comprising graduated functional exercises initiated at 14 days, with progressive restoration of shoulder abduction and flexion limited to 90\u0026deg; for the initial 6 postoperative weeks. Vigorous physical activities were restricted for an additional 3 months to ensure soft tissue maturation. Elective removal of the SC hook plate was generally scheduled between 6 and 12 months postoperatively, contingent upon radiographic evidence of osseous union and clinical stability.\u003c/p\u003e\n\u003cp\u003eA comprehensive surveillance strategy was adopted, incorporating immediate postoperative radiographic assessment (within 24 hours) via anteroposterior and axial radiographs complemented by computed tomography (CT) to confirm anatomic reduction, hardware positioning. Serial follow-up imaging included biplanar radiographs at 1, 3, 6, and 12 months, with adjunctive CT scans at 6 and 12 months for patients with post-traumatic SCJ instability. Radiologic evaluations focused on joint congruency, hardware integrity (including screw migration or cortical penetration), and osseous integration. All imaging studies were independently interpreted by two fellowship-trained musculoskeletal radiologists, with interobserver discrepancies resolved via consensus conference. Clinical assessments were conducted at standardized intervals (2 weeks, 1, 3, 6, and 12 months) utilizing validated metrics, including the Constant-Murley Shoulder Score (CSS) and Visual Analog Scale (VAS) for pain. Longitudinal surveillance beyond 24 months incorporated annual clinical evaluations and telemedicine follow-ups to monitor functional outcomes and identify delayed complications.\u003c/p\u003e\n\u003ch3\u003e1.4 Data Collection\u003c/h3\u003e\n\u003cp\u003eA comprehensive surveillance strategy was adopted, incorporating immediate postoperative radiographic assessment (within 24 hours) via anteroposterior and axial radiographs complemented by computed tomography (CT) to confirm anatomic reduction, hardware positioning. Serial follow-up imaging included biplanar radiographs at 1, 3, 6, and 12 months, with adjunctive CT scans at 6 and 12 months for patients with post-traumatic SCJ instability. Radiologic evaluations focused on joint congruency, hardware integrity (including screw migration or cortical penetration), and osseous integration. All imaging studies were independently interpreted by two fellowship-trained musculoskeletal radiologists, with interobserver discrepancies resolved via consensus conference. Clinical assessments were conducted at standardized intervals (2 weeks, 1, 3, 6, and 12 months) utilizing validated metrics, including the Constant-Murley Shoulder Score (CSS) and Visual Analog Scale (VAS) for pain. Longitudinal surveillance beyond 24 months incorporated annual clinical evaluations and telemedicine follow-ups to monitor functional outcomes and identify delayed complications.\u003c/p\u003e\n\u003ch3\u003e1.5 Statistical Analysis\u003c/h3\u003e\n\u003cp\u003eA comparative analysis between preoperative and postoperative outcomes was conducted using statistical tests, such as paired t-tests, to assess changes in joint function and pain levels, contributing to a comprehensive evaluation of the effectiveness of hook plates in improving patient recovery.\u003c/p\u003e"},{"header":"Results","content":"\u003ch3\u003e2.1 Patient Demographics and Clinical Data\u003c/h3\u003e\n\u003cp\u003eThe study cohort consisted of\u0026nbsp;46 individuals who underwent treatment with SC hook plates for SCJ dislocations between 2015 and 2022. The demographic analysis revealed a mean age of 49.3 years (range: 28 to 73 years), with a predominant representation of male patients (44 males, 2 females). High-energy trauma, primarily resulting from traffic accidents (44 cases) and sports injuries (2 cases), was the most common\u0026nbsp;mechanism of injury. 42 cases were classified as anterior dislocations, and 4 cases as posterior dislocations. This classification is important due to\u0026nbsp;the increased risks associated with posterior dislocations,\u0026nbsp;highlighting the significance of using hook plates in these cases\u0026nbsp;(Table 1).\u003c/p\u003e\n\u003ch3\u003e2.2 Surgical Outcomes\u003c/h3\u003e\n\u003cp\u003eThe average operative duration for the 46 patients undergoing SC hook plate fixation varied between 55 and 95 minutes, with a mean of 65.2 \u0026plusmn; 8.4 minutes. Notably, there were no instances of nerve or vascular injuries reported as intraoperative complications,\u0026nbsp;no\u0026nbsp;patients experienced localized skin complications, including erythema, ulceration, or device-related pressure injuries, attributable to hardware prominence. and the average blood loss during surgery was minimal at 46.2 \u0026plusmn; 14.6 mL.\u0026nbsp;Preoperatively, the mean CSS was 36.4 \u0026plusmn; 4.8 points (range: 28-46 points). At the final follow-up, the postoperative mean CSS score significantly improved to 86.6 \u0026plusmn; 6.2 points (range: 80-92) at the final follow-up, with a p-value of\u0026nbsp;\u0026lt;0.05, indicating a statistically significant difference.\u0026nbsp;Additionally, the mean VAS score improvement from 7.2 \u0026plusmn; 1.4 (range: 5-8) preoperatively to 1.6 \u0026plusmn; 0.4 (range: 0-3) at the final follow-up, a p-value of\u0026nbsp;\u0026lt;0.05, denoting a statistically significant difference. Postoperative\u0026nbsp;radiographic assessments, including\u0026nbsp;X-rays and CT scans, consistently demonstrated\u0026nbsp;successful joint repositioning in\u0026nbsp;all cases, with the hook plates effectively maintaining proper SCJ alignment. Throughout the follow-up period, hardware integrity remained intact, with no instances of significant hardware loosening or displacement immediately post-surgery, However,\u0026nbsp;a few cases of hardware-related complications emerged during recovery. Scheduled removal at 6\u0026ndash;12 months is safe and recommended, with intraoperative stability testing to confirm adequate healing before implant extraction.\u003c/p\u003e\n\u003ch3\u003e2.3 Complications and Hardware Issues\u003c/h3\u003e\n\u003cp\u003eFollowing the use of SC hook plates, the study identified several hardware-related complications. Notably, a 66-year-old male patient (2%) experienced fixation failure and redislocation within 10 days post-surgery, necessitating revision surgery (Fig.3). Additionally, during follow-ups, plate breakages were observed in 4 patients (8.7%) (Fig.4), although these occurrences did not result in redislocation or require immediate revision surgeries.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study validates the biomechanical efficacy of SC hook plates in achieving joint reduction and functional restoration for SCJ dislocations. Radiographic evaluation confirmed successful stabilization in 98% of cases, with postoperative CSS improving significantly from 36.4 \u0026plusmn; 4.8 preoperatively to 86.6 \u0026plusmn; 6.2 at final follow-up (p \u0026lt; 0.05), reflecting substantial recovery of shoulder kinematics. Concurrent reductions in VAS scores (7.2 \u0026plusmn; 1.4 preoperatively to 1.6 \u0026plusmn; 0.4 postoperatively, p \u0026lt; 0.05) corroborate effective pain alleviation, critical for early mobilization and rehabilitation compliance. However, these functional gains are tempered by hardware-related complications, including asymptomatic plate breakage (8.7%) and fixation failure necessitating revision surgery (2%). Notably, complications disproportionately occurred in patients with osteoporosis or high-energy trauma, suggesting a mechanistic interplay between bone quality, trauma biomechanics, and implant stress distribution.\u003c/p\u003e\n\u003cp\u003eThe observed complications align with biomechanical studies identifying stress concentration at the hook-bone interface as a predisposing factor for plate failure [7]. This phenomenon underscores the critical balance between achieving mechanical stability and mitigating long-term implant fatigue, particularly in high-risk cohorts. While the absence of neurovascular injuries and low redislocation rate (2%) demonstrate the technique\u0026rsquo;s safety profile, the trade-off between immediate stabilization and delayed hardware degradation warrants scrutiny. The low preoperative CSS also reflects the combined impact of SCJ instability, pain-mediated functional impairment, and compensatory shoulder mechanics, emphasizing the urgency of timely intervention to restore global shoulder function. Future investigations should prioritize longitudinal CSS and VAS assessments to elucidate the interplay between hardware integrity, joint stability, and sustained clinical outcomes. Additionally, biomechanical optimization of implant design\u0026mdash;such as modifying hook curvature or incorporating locking mechanisms\u0026mdash;and extended follow-up protocols are essential to address these risks in complex dislocations or osteoporotic bone.\u003c/p\u003e\n\u003cp\u003eConservative management\u0026nbsp;(e.g., closed reduction and immobilization) are often preferred for stable anterior dislocations; however, it may fail to provide long-term stability in some cases. This failure can result in chronic instability, a higher risk of\u0026nbsp;redislocation\u0026nbsp;(up to 21\u0026ndash;100%)\u003csup\u003e[9]\u003c/sup\u003e, and poor functional outcomes\u003csup\u003e[10]\u003c/sup\u003e, including persistent pain, decreased functionality, post-traumatic arthritis, and cosmetic deformities. Moreover, in cases of severe dislocation, conservative treatment often falls short in restoring full joint stability, increasing the likelihood of requiring surgical intervention for better long-term recovery. In contrast, surgical intervention with hook plates provides immediate stability, early mobilization, and significantly lower redislocation rates (2% in our cohort), although it is associated with hardware-related risks. This highlights the importance of individualized treatment plans based on dislocation severity and patient-specific factors.\u003c/p\u003e\n\u003cp\u003eComparison between SC hook plates and other techniques, such as acromioclavicular (AC) hook plates and ligament repair (using\u0026nbsp;artificial or autologous ligaments), reveals distinct differences. AC hook plates are commonly used for AC joint dislocations due to their robust fixation properties and ability to maintain reduction. Qu et al. \u003csup\u003e[7]\u003c/sup\u003e\u0026nbsp; reported\u0026nbsp;successful treatment of 10 patients with anterior SCJ dislocation using AC hook plates without complications, with a follow-up of 16.9 months, providing sufficient short-to-medium-term outcomes but lacking the long-term complications observed in this study. Ligament repair, whether using\u0026nbsp;artificial or autologous grafts, takes\u0026nbsp;a more biological approach\u0026nbsp;by relying on the body\u0026apos;s natural healing mechanisms. This method typically involves longer recovery periods due to the dependence on ligament healing and carries a heighter risk of redislocation in severe trauma cases compared to the immediate stabilization provided by hook plates. Nevertheless, ligament repair has\u0026nbsp;the advantage of avoiding hardware complications and may be preferable in less severe dislocations, where the risk of hardware failure is minimal\u003csup\u003e[11-14]\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eSeveral less invasive techniques, such as Button devices connected to suture and minimally invasive suture fixation, offers a more anatomical approach, particularly for chronic instability or low-demand injuries, However, these techniques requires prolonged rehabilitation and may lack sufficient stability in high-energy trauma\u003csup\u003e[11]\u003c/sup\u003e. Minimally invasive techniques, such as FiberWire\u0026reg; fixation, avoid hardware-related complications but may be less effective in cases of severe ligamentous disruption or osteoporotic bone\u003csup\u003e[12, 15]\u003c/sup\u003e. While these methods have the advantage of avoiding hardware issues, they may not be suitable for acute, unstable posterior dislocations or high-demand patients requiring rapid stabilization. The choice of technique should be tailored to injury severity, patient characteristics, and functional demands, underscoring the need for further comparative studies to optimize treatment selection.\u003c/p\u003e\n\u003cp\u003eThis study makes a significantly contribution by addressing complications, challenges, and long-term outcomes associated with SC hook plates in treatment of SCJ dislocation, complementing the generally favorable outcomes reported in earlier studies\u003csup\u003e[6-8, 16, 17]\u003c/sup\u003e ，While past research indicated no complications, wound infections, or plate/screw breakages, this study highlights potential risks, offering a more comprehensive understanding of long-term performance and hardware-related complications in specific patient subsets. By identifying this novel complication, absent in prior studies, this research underscores potential gaps in earlier evaluations, emphasizing the importance of thorough long-term monitoring and hardware performance analysis. This discovery suggests that previous studies may have underestimated certain risks over extended periods or in specific patient groups, contributing to the refinement of clinical practice through rigorous postoperative follow-up and surgical technique adaptation to proactively address future treatment challenges. Furthermore, this finding underscores the ongoing need for plate design innovation and continued research to capture the full spectrum of associated linked with SC hook plates.\u003c/p\u003e\n\u003cp\u003eWhile the study documented 8.7% plate breakage rate, it is critical to acknowledge the biomechanical challenges inherent in any bridging implant spanning a dynamic joint. Like acromioclavicular (AC) hook plates, which are prone to fatigue failure over time due to cyclic loading at the joint interface, SC hook plates are similarly subjected to repetitive stress from clavicular motion during shoulder activities. This risk is compounded by the SCJ\u0026rsquo;s unique mobility, which involves translation and rotation during arm movement. Previous studies on AC hook plates report long-term use, underscoring the principle that bridging constructs across articulations may inherently fail due to mechanical fatigue rather than acute overload\u003csup\u003e[18]\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eGiven this biomechanical reality, early implant removal (6\u0026ndash;12 months postoperatively) is recommended to mitigate late hardware failure. This aligns with current guidelines for AC hook plates, where removal after 6 months reduces stress shielding and fatigue risks. In our cohort, all plate breakages occurred in patients who retained implants beyond 6 months, suggesting a temporal association with hardware fatigue. While immediate stability is essential for healing, prolonged retention may paradoxically increase failure risk. Future studies should prospectively evaluate outcomes of accelerated implant removal protocols (e.g., 6 months) in low-demand patients versus delayed removal in high-demand individuals.\u003c/p\u003e\n\u003cp\u003eThe absence of dislocation following hardware failure suggests that bony and soft-tissue healing may provide sufficient joint stability once implant degradation occurs, underscoring the hook plate\u0026rsquo;s transient role in maintaining anatomical alignment during the critical healing phase. This biomechanical interplay implies that prolonged implant dependency may be unnecessary in select patients, particularly those at risk of delayed healing (e.g., osteoporosis, smoking), where alternative strategies like ligament reconstruction could mitigate hardware-related morbidity. Surgeons must balance early mobilization benefits against the 8.7% incidence of asymptomatic plate fractures and 2% fixation failures, emphasizing patient education on scheduled explantation to prevent delayed complications. Innovations in biomaterials\u0026mdash;such as fatigue-resistant titanium alloys or bioabsorbable implants\u0026mdash;may address these limitations while preserving the plate\u0026rsquo;s capacity to achieve immediate mechanical stability, particularly in complex posterior dislocations near critical neurovascular structures. However, the inclusion of heterogeneous dislocation types (anterior/posterior) introduces confounding variables, as posterior injuries\u0026mdash;though numerically fewer\u0026mdash;present unique anatomical challenges requiring specialized surgical considerations. The study\u0026rsquo;s retrospective design and limited posterior dislocation subgroup size (n=4) restrict definitive conclusions about subgroup-specific outcomes, necessitating prospective stratification in future investigations to refine risk-benefit profiles for distinct injury patterns. These findings collectively advance the paradigm of minimally invasive stabilization while highlighting the imperative for continued innovation in implant design and patient-specific surgical planning.\u003c/p\u003e\n\u003cp\u003eSC hook plates are recommended for acute, unstable posterior dislocations requiring immediate stabilization to protect critical structures, high-energy trauma with severe ligamentous disruption, and high-demand patients (e.g., athletes) needing rapid mobilization. Conversely, alternative techniques (e.g., ligament repair, suture fixation) are preferable for stable anterior dislocations, chronic instability without bony involvement, osteoporotic patients at risk of hardware failure, or low-demand individuals tolerant of prolonged rehabilitation. Patient-specific factors\u0026mdash;injury severity, bone quality, functional needs, and risk tolerance\u0026mdash;should guide treatment selection. Future implant designs should prioritize ergonomic shapes and durable materials to mitigate complications, expanding safe applicability across diverse clinical scenarios.\u003c/p\u003e\n\u003cp\u003eThe retrospective study design, small sample size, and limited follow-up duration are notable limitations, reduce the generalizability of findings and prevent a comprehensive assessment of long-term complications. To address these limitations, future research should include larger sample sizes, prospective studies, and extended follow-up periods to further explore the enduring efficacy of the plates. Additionally, recommending enhancements in implant design and surgical techniques is crucial for minimizing risks and ensuring superior outcomes for patients with SCJ dislocation.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study affirms the effectiveness of SC hook plates in stabilizing traumatic SCJ dislocations, particularly in cases requiring immediate mechanical stability. However, the observed hardware-related complications, such as fixation failure and plate breakages, highlight the need for ongoing innovation in implant design and surgical techniques. Future research should prioritize the development of more durable implants, comprehensive long-term outcome assessments, and individualized treatment strategies to optimize patient outcomes.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch3\u003eEthics Approval and Consent to Participate:\u003c/h3\u003e\n\u003cp\u003eThe study was approved by the Ethics Committee of\u0026nbsp;Taizhou Hospital of Zhejiang Province of Ethics Committee (Approval Number: kL20240919). Informed consent was obtained from all participants prior to inclusion in the study.\u003c/p\u003e\n\u003ch3\u003eConsent for Publication:\u003c/h3\u003e\n\u003cp\u003eWritten informed consent for publication of their clinical details and images was obtained from the parents or legal guardians of the patients. A copy of the consent form is available for review by the Editor of this journal.\u003c/p\u003e\n\u003ch3\u003eAvailability of Data and Materials:\u003c/h3\u003e\n\u003cp\u003eThe datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003ch3\u003eCompeting Interests:\u003c/h3\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003ch3\u003eFunding:\u003c/h3\u003e\n\u003cp\u003eThis work was funded by the\u0026nbsp;Enze Medical Center (Group) Scientific Research Fund (19EZC28, 21EZD21).\u003c/p\u003e\n\u003ch3\u003eAuthors\u0026apos; Contributions:\u003c/h3\u003e\n\u003cp\u003e[Li Sheng] designed the study. [Yaiqing Wu, Jie Feng] collected and analyzed the data. [Xiaoyong Sheng] contributed to the writing and editing of the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003ch3\u003eAcknowledgments:\u003c/h3\u003e\n\u003cp\u003eWe would like to thank Taizhou Hospital of Zhejiang Province for their assistance and support in this study.\u003c/p\u003e"},{"header":" References","content":"\u003col\u003e\n \u003cli\u003eMiniato M. A.,Anand P., Varacallo M.,Anatomy, Shoulder and Upper Limb, Shoulder[J]2021,\u003c/li\u003e\n \u003cli\u003eKiel J.,Ponnarasu S., Kaiser K.,Sternoclavicular Joint Injury[J]2021,\u003c/li\u003e\n \u003cli\u003eWang S.,Chen Z.,Lin L., et al. ,Long-term results for traumatic sternoclavicular joint dislocation treated with a sternoclavicular joint-specific plate[J].ANZ J Surg,2021,91(4):653-657\u003c/li\u003e\n \u003cli\u003eTasnim S.,Shirafkan A., Okereke I.,Diagnosis and management of sternoclavicular joint infections: a literature review[J].J Thorac Dis,2020,12(8):4418-4426\u003c/li\u003e\n \u003cli\u003eLacheta L.,Dekker T. J.,Goldenberg B. 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G., et al. ,Controversies relating to the management of acromioclavicular joint dislocations[J].Bone Joint J,2013,95-b(12):1595-1602\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Table","content":"\u003cp\u003eTable 1 is available in the Supplementary Files section\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Sternoclavicular Hook, Sternoclavicular joint Dislocation, Hardware Failure, Joint Stabilization, Postoperative Outcomes","lastPublishedDoi":"10.21203/rs.3.rs-6338049/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6338049/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective: \u003c/strong\u003eThis study evaluates the efficacy and complications associated with sternoclavicular（SC）hook plates in treating traumatic sternoclavicular joint (SCJ) dislocations.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eA retrospectively analyzed on patients who underwent SC hook plates forfixation SCJ dislocations, focusing on hardware-related complications such as plate breakages and fixation failures. Clinical outcomes, functional recovery, and complications were assessed. Postoperative imaging, including X-raysand CT scans, was used to evaluate joint reduction and hardware integrity, Functional out comes were measured using the Constant Shoulder Score (CSS) and Visual Analog Scale (VAS) for pain.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eSC\u003cstrong\u003e \u003c/strong\u003ehook plates effectively stabilized the joint and significantly improved function, as demonstrated by an increase in the mean CSS scores from 36.4 preoperatively to 86.6 postoperatively, and a decrease in VAS scores from 7.2 to 1.6. However, 4 patients (8.7%) experienced plate breakages without redislocation, and 1 patient (2%) experienced fixation failure, requiring revision surgeries. No major neurovascular complications were observed.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eWhile SC hook plates provide effective stabilization for SCJ dislocations, they are associated with hardware-related complications, including plate breakages and fixation failures. Improvements in implant design, patient selection are necessary to address these issues and improve long-term outcomes. Future research should focus on the developing of more ergonomic implants and exploration of alternative treatment options.\u003c/p\u003e","manuscriptTitle":"Novel Sternoclavicular Hook Plate for Traumatic Dislocations: Functional Outcomes and Complications","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-05 05:40:26","doi":"10.21203/rs.3.rs-6338049/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"310f66ba-9d23-4263-81f1-5fd0a2d0736f","owner":[],"postedDate":"May 5th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-05-05T05:40:26+00:00","versionOfRecord":[],"versionCreatedAt":"2025-05-05 05:40:26","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6338049","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6338049","identity":"rs-6338049","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}