Epidemiological Characteristics and Risk Factors for Closed Reduction Failure in Pediatric Extension-type Supracondylar Humerus Fractures: A Study from a Regional General Hospital

Epidemiological Characteristics and Risk Factors for Closed Reduction Failure in Pediatric Extension-type Supracondylar Humerus Fractures: A Study from a Regional General Hospital | 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 Epidemiological Characteristics and Risk Factors for Closed Reduction Failure in Pediatric Extension-type Supracondylar Humerus Fractures: A Study from a Regional General Hospital Qinqin Li, Yuchang Dong, Ye Li, Qingbing He, Jinchao Cao, Jiuhui Han, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6238231/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 10 You are reading this latest preprint version Abstract Background Supracondylar humerus fractures (SCHFs) are the most common pediatric elbow fractures, with extension-type fractures being the predominant subtype. While closed reduction and percutaneous pinning (CRPP) is the standard treatment for displaced extension-type SCHFs, failure of closed reduction remains a significant concern. Such failures often necessitate more invasive procedures and are associated with increased complications. Although previous studies have explored potential risk factors for closed reduction failure, comprehensive epidemiological data and consistent conclusions remain limited. This study aims to analyze the epidemiological characteristics and identify risk factors for closed reduction failure in pediatric extension-type SCHFs at a regional general hospital, providing evidence to enhance clinical management strategies. Study design A retrospective analysis was conducted on 981 pediatric patients diagnosed with extension-type SCHFs and treated at Third Hospital of Hebei Medical University between January 2016 and December 2022. Data on patient demographics, clinical characteristics, and surgical details were collected. Univariate and multivariate logistic regression analyses were performed to identify risk factors for closed reduction failure. Results Among the study cohort, 615 patients (62.69%) were male and 366 (37.31%) were female, with a mean age of 4.04 ± 2.61 years. The peak incidence was observed at five years of age, with a high-incidence plateau between three and seven years. Seasonal variations were noted, with a higher incidence in spring and summer. The overall success rate of closed reduction was 91.64%, whereas the failure rate was 8.36%. Multivariate logistic regression identified several significant independent risk factors for closed reduction failure: older age (OR = 2.705, 95% CI: [2.07, 3.53]), higher Gartland classification (OR = 5.048, 95% CI: [2.61, 9.76]), radial displacement (OR = 2.038, 95% CI: [1.46, 2.85]), and concomitant injuries (OR = 0.350, 95% CI: [0.19, 0.63]). Conclusion Extension-type SCHFs are most prevalent among preschool-aged children, particularly 5-year-old boys, with peak incidence occurring in spring and summer. Older age, higher Gartland classification, concomitant injuries, and radial displacement are significant independent risk factors for closed reduction failure. These findings highlight the necessity of individualized treatment strategies to optimize outcomes in pediatric SCHFs management and minimize the need for invasive interventions. Supracondylar humerus fractures Extension-type Closed reduction failure risk factors Epidemiology Figures Figure 1 Figure 2 Figure 3 Background Supracondylar humerus fractures (SCHFs) represent the most common pediatric elbow fractures, accounting for up to 60% of all elbow injuries in children [ 1 – 3 ]. Among these, extension-type fractures, typically caused by a fall on an outstretched hand, are the predominant sub-type. Although closed reduction and percutaneous pinning (CRPP) is widely regarded as the standard treatment for displaced extension-type SCHFs [ 4 ], closed reduction failure remains a significant clinical concern. Failed closed reduction often necessitates more invasive procedures, such as open reduction, and increases the risk of complications, including infection, scar formation, neurovascular injury, malunion, and long-term functional deficits [ 5 – 7 ]. Previous studies have explored potential risk factors for closed reduction failure in pediatric extension-type SCHFs, including fracture severity, delayed treatment, and surgeon experience. Nevertheless, comprehensive data on epidemiological characteristics and risk factors remain scarce, with existing findings often inconsistent and limited by small sample sizes [ 8 – 11 ]. Moreover, regional variations in the incidence and management of these fractures have not been thoroughly investigated, despite their potential impact on clinical outcomes. This study aims to address these gaps by analyzing the epidemiological characteristics and identifying risk factors for closed reduction failure in pediatric extension-type SCHFs within a regional general hospital setting. By examining a large, homogeneous patient cohort, we seek to generate robust evidence that can inform clinical decision-making and refine the management of these common yet complex injuries. Materials and methods Study population This retrospective study analyzed the case data of 981 pediatric patients with extension-type SCHFs admitted to the Pediatric Orthopedic Department of Third Hospital of Hebei Medical University between January 2016 and December 2022. Inclusion criteria were as follows: (1) a diagnosis of extension-type SCHFs requiring surgical treatment; (2) availability of complete clinical and imaging data; (3) treatment exclusively received at our hospital; and (4) age < 18 years at the time of injury. Exclusion criteria included: (1) incomplete data; (2) missing clinical or imaging data; (3) presence of congenital or severe systemic diseases (e.g., pathological fractures); and (4) treatment at other medical institutions. The study was approved by the Ethics Committee of the Third Hospital of Hebei Medical University, and stringent measures were taken to ensure patient privacy. Data collection Data collected included patient demographics (age, gender, height, and weight), clinical characteristics (fracture laterality, presence of complications, fracture type, and classification), and surgical details (time from injury to surgery and reduction method). Body mass index (BMI) was calculated as weight (kg) divided by height squared (m²). Extension-type fractures were further categorized using the Gartland classification: Type I (non-displaced), Type II (displaced with intact posterior cortex), and Type III (displaced with no cortical contact). In anteroposterior elbow radiographs, displacement of the fracture was recorded. Complications included nerve injuries, vascular injuries, and concomitant fractures. Surgical reduction methods were classified as either closed reduction or open reduction, with open reduction cases defined as closed reduction failures. Grouping and study design This study employed a retrospective case-control design. Univariate and multivariate regression analyses were performed to identify potential risk factors for closed reduction failure. BMI was compared with age- and gender-matched reference values, with BMI >85th percentile classified as overweight and BMI >95th percentile as obese. Based on the season of injury, patients were categorized into four groups: Spring (March to May), Summer (June to August), Autumn (September to November), and Winter (December to February). Additional groupings were established based on fracture classification. In anteroposterior elbow radiographs, fractures without displacement are classified as the normal group, those with posteromedial displacement as the ulnar deviation group, and those with posterolateral displacement as the radial deviation group. Statistical analysis Data analysis was conducted using SPSS 26.0 statistical software. Quantitative data are expressed as mean ± standard deviation (x̄ ± s), and group comparisons were performed using independent samples t-tests. Qualitative data are presented as frequencies and percentages, with group comparisons made using chi-square tests. The Shapiro-Wilk test was used to assess the normality of data distribution. For normally distributed variables, t-tests were used, while the Mann-Whitney U test was applied for non-normally distributed variables. The relationships between factors such as age, gender, fracture type, BMI, and closed reduction failure rates were analyzed using one-way ANOVA or chi-square tests. Factors identified through screening were further analyzed using logistic regression models, with statistical significance set at P < 0.05. Results From January 2016 to December 2022, a total of 981 pediatric patients diagnosed with extension-type SCHFs met the inclusion criteria. Of these, 615 were male (62.69%) and 366 were female (37.31%). The fractures were located on the left side in 528 cases (53.82%) and on the right side in 453 cases (46.18%). According to the Gartland classification, 455 cases (46.38%) were classified as Type II, while 526 cases (53.62%) were Type III. Associated injuries were present in 105 patients (10.70%), including median nerve injury in 50 cases (5.10%), radial nerve injury in 32 cases (3.26%), brachial artery injury in 27 cases (2.75%), concomitant fractures in 16 cases (1.63%), and ulnar nerve injury in 1 case (0.10%). Notably, some patients exhibited multiple associated injuries (Table 1). Age Distribution In Shijiazhuang and surrounding areas of Hebei Province, the incidence of SCHFs followed a characteristic "rise-and-fall" pattern. The peak incidence occurred at five years of age, with a high-incidence plateau observed between three and seven years. After the age of eight, the incidence rate declined markedly, with only four cases reported in children aged 13 years or older (Figure 1). The mean age of the study population was 4.04 ± 2.61 years (range: 6 months to 14 years). Gender Characteristics Males were significantly more affected than females (615 vs. 366 cases, 63% vs. 37%; P < 0.05). The male predominance was evident across all age groups, with the most pronounced gender disparities observed in the 6–8 and 9–11-year age groups. The highest incidence among males occurred in the 6–8-year group (220 cases), whereas females exhibited a smaller peak at 3–5 years (151 cases). However, at all ages, the incidence remained consistently lower in females compared to males (Figure 2). BMI Distribution The mean BMI of the study population was 15.94 ± 2.62 kg/m². Based on weight classification, 800 patients (81.55%) had normal weight, 121 (12.33%) were classified as obese, and 60 (6.12%) were overweight. Among patients with Gartland II fractures, 371 (37.82%) had normal weight, 63 (6.42%) were obese, and 29 (2.96%) were overweight. In contrast, among those with Gartland III fractures, 429 (43.73%) had normal weight, 58 (5.91%) were obese, and 31 (3.16%) were overweight. No significant differences were observed in fracture type distribution across different weight categories (P > 0.05) (Table 1). Monthly and Seasonal Distribution The number of cases showed a clear seasonal pattern, gradually increasing from January, peaking in May (136 cases), and subsequently declining to the lowest point in December (25 cases). The highest incidence was recorded in spring (March–May, 283 cases) and summer (June–August, 330 cases), with May representing the annual peak. Conversely, the lowest incidence was observed in winter (December–February, 101 cases). These seasonal variations may be associated with environmental factors such as temperature and humidity, as well as changes in children's activity patterns, although further investigation is warranted. Univariate Analysis of Closed Reduction Failure Closed reduction is widely accepted as the standard treatment for extension-type SCHFs. In this cohort, the overall success rate of closed reduction was 91.64% (899 cases), significantly higher than the failure rate of 8.36% (82 cases) (P < 0.05) (Figure 3). Univariate analysis identified age, Gartland classification, the presence of concomitant injuries, and fracture displacement as significant factors associated with closed reduction failure (P 0.05) (Table 2). Patients in the closed reduction group were significantly younger (5.05 ± 2.61 years) compared to those requiring open reduction (6.20 ± 3.01 years) (P < 0.05). The failure rate of closed reduction was significantly higher in patients with Gartland III fractures compared to Gartland II fractures (P < 0.05). Additionally, the failure rate was substantially higher in patients with associated injuries (23.81%) compared to those without (6.51%) (P < 0.05). Regarding fracture displacement, cases with radial deviation had a significantly higher closed reduction failure rate (17.00%) compared to those with ulnar deviation (6.79%) or no displacement (4.10%) (P 0.05). Multivariate Logistic Regression Analysis Multivariate logistic regression analysis identified age, Gartland classification, and fracture displacement as significant independent risk factors for closed reduction failure. The odds ratios (OR) were 2.705 (95% CI: [2.07, 3.53]), 5.048 (95% CI: [2.61, 9.76]), and 2.038 (95% CI: [1.46, 2.85]), respectively (P < 0.001 for all). In contrast, the absence of concomitant injuries was identified as a protective factor, reducing the risk of closed reduction failure by 65% (OR = 0.350, 95% CI: [0.19, 0.63], P < 0.001). These findings underscore the importance of considering patient age, fracture severity (Gartland classification and displacement direction), and associated injuries when formulating treatment strategies for pediatric extension-type SCHFs (Table 3). Discussion Supracondylar humerus fractures (SCHFs) are the most common pediatric elbow fractures, with extension-type fractures being the most prevalent [1-3]. Despite advancements in treatment, closed reduction failure remains a significant challenge, often necessitating open reduction and increasing the risks of infection, neurovascular injury, and long-term functional impairments [5-7]. This study investigates the epidemiological characteristics and identifies risk factors for closed reduction failure in pediatric extension-type SCHFs in a regional hospital setting, providing evidence-based insights to enhance clinical management and improve patient outcomes. Our cohort of 981 patients exhibited a male predominance (63%), consistent with previous studies reporting higher SCHF rates in boys, likely due to their greater involvement in high-risk activities and sports [12]. The peak incidence occurred at five years of age, with a high-incidence plateau between three and seven years [13], coinciding with the period when children are most active and susceptible to falls [14]. This observation aligns with existing literature suggesting that younger children are more vulnerable to SCHFs due to weaker bones and higher activity levels [15]. The incidence decreased after the age of eight, likely due to improved motor skills, greater bone strength, and reduced risk-taking behavior [15]. In the regions of China , the climate is characterized by four distinct seasons. In the incidence of SCHFs, seasonal variations were also observed, with peaks in spring and summer, likely due to increased outdoor activities during warmer months. This finding is consistent with previous studies linking seasonal changes in physical activity to higher pediatric fracture rates. For example, Ausó-Pérez et al. [16] reported an increased incidence of pediatric fractures during warmer months, correlating with heightened outdoor play. These findings highlight the importance of preventive strategies, such as parental supervision and safety education, particularly during high-incidence periods and among high-risk populations. Several significant risk factors for closed reduction failure were identified in this study, including older age, higher Gartland classification (Type III fractures), and fracture displacement (particularly radial displacement). These findings align with previous research indicating that more severe fractures are more challenging to reduce due to greater soft tissue interposition, instability, and difficulties in achieving anatomical alignment [17, 18]. Gartland Type III fractures have been independently associated with an increased risk of closed reduction failure [17], as severe displacement often precludes satisfactory alignment through closed reduction alone [19]. Similarly, radial displacement has been linked to higher failure rates, with Ondina et al reporting that posterolateral displacement frequently necessitates open reduction due to the difficulty in achieving stable closed reduction [20]. The higher failure rates observed in older children may be attributed to increased bone density and reduced plasticity, which complicate reduction. Older children with SCHFs often present with more complex fracture patterns, necessitating more aggressive treatment [12]. Additionally, concomitant injuries, such as neurovascular damage, were associated with higher failure rates due to increased fracture complexity and the need for more extensive surgical intervention. These findings are consistent with previous studies demonstrating that concomitant injuries significantly raise the likelihood of open reduction [18, 20, 21]. Moreover, the increased failure rate of closed reduction in patients with concomitant injuries aligns with prior findings [18], suggesting that complex fracture displacement and soft tissue interposition significantly heighten reduction difficulty. The association between neurovascular injuries and the need for open reduction further emphasizes the importance of early identification of high-risk cases to optimize treatment strategies [18, 20-22]. Interestingly, gender, BMI, and fracture laterality (left vs. right) did not significantly influence closed reduction outcomes. This finding contrasts with some previous studies suggesting that obesity may complicate fracture reduction [22]. However, Ondina et al. found no significant association between BMI and closed reduction success in pediatric SCHFs [20]. This discrepancy may be attributable to differences in study populations or the relatively low prevalence of obesity in our cohort. Strengths and limitations To our knowledge, this is one of the largest single-center studies examining risk factors for closed reduction failure in pediatric extension-type SCHFs. However, the retrospective design limits the ability to establish causal relationships, and the single-center nature may restrict the generalizability of findings. Additionally, factors such as surgeon experience and potential confounders, including injury timing and comorbidities, were not analyzed and warrant further investigation. The low prevalence of obesity in our cohort may explain the lack of a significant association between BMI and closed reduction failure, underscoring the need for studies in more diverse populations. Conclusion Extension-type SCHFs are most prevalent among preschool-aged children, particularly 5-year-old boys, with peak incidence occurring in spring and summer. Older age, higher Gartland classification, concomitant injuries, and radial displacement are significant independent risk factors for closed reduction failure. These findings highlight the necessity of individualized treatment strategies to optimize outcomes in pediatric SCHFs management and minimize the need for invasive interventions. Abbreviations BMI Body Mass Index CI Confidence Interval CRPP: Closed Reduction and Percutaneous Pinning OR Odds Ratio SCHFs Supracondylar Humerus Fractures ANOVA Analysis of Variance Declarations Acknowledgements The authors would like to thank all the research assistants who helped support and collect the data used for the study. Author contributions “DX” and “QL”designed the study and drafted the manuscript. “YD” performed statistical analyses. “YL”, “QH”, and “JC” contributed to data collection and interpretation. “JH” and “ZL” supervised the research and critically revised the manuscript. All authors reviewed the final draft of the study and approved it for publication. All authors agree to be personally accountable for the submitted literature. Funding No funding or sponsorship was received for this study. Data availability The datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request. Ethics approval and consent to participate The study was started after approval by Ethics Committee of the Third Hospital of Hebei Medical University and Approval Number KE-2025-009-1. Informed consent was obtained from legal guardians of the subjects enrolled in the study. This study was performed in accordance with the Declaration of Helsinki. Consent for publication Not Applicable Competing interests The authors declare no competing interests. Clinical trial number Not applicable Author details 1 Department of Pediatric Orthopedics, Third Hospital of Hebei Medical University, Shijiazhuang City, China. 2 Department of Pediatric Surgery, Second Hospital of Hebei Medical University, Shijiazhuang City, China. 3 Hebei University of Chinese Medicine, Shijiazhuang City, China. References Zorrilla SdNJ, Prada-Cañizares A, Marti-Ciruelos R, Pretell-Mazzini J. Supracondylar humeral fractures in children: current concepts for management and prognosis. Int Orthop. 2015;39(11):2287–96. Pennock AT, Charles M, Moor M, Bastrom TP, Newton PO. Potential causes of loss of reduction in supracondylar humerus fractures. J Pediatr Orthop. 2014;34(7):691–7. Saeed W, Waseem M. Elbow Fractures Overview. StatPearls. edn. Treasure Island (FL) ineligible companies. Disclosure: Muhammad Waseem declares no relevant financial relationships with ineligible companies.: StatPearls Publishing Copyright © 2024. StatPearls Publishing LLC.; 2024. Tomaszewski R, Pethe K, Kler J, Rutz E, Mayr J, Dajka J. Supracondylar Fractures of the Humerus: Association of Neurovascular Lesions with Degree of Fracture Displacement in Children-A Retrospective Study. Child (Basel) 2022, 9(3). Duffy S, Flannery O, Gelfer Y, Monsell F. Overview of the contemporary management of supracondylar humeral fractures in children. Eur J Orthop Surg Traumatol. 2021;31(5):871–81. Babal JC, Mehlman CT, Klein G. Nerve injuries associated with pediatric supracondylar humeral fractures: a meta-analysis. J Pediatr Orthop. 2010;30(3):253–63. Sankar WN, Hebela NM, Skaggs DL, Flynn JM. Loss of pin fixation in displaced supracondylar humeral fractures in children: causes and prevention. J Bone Joint Surg Am. 2007;89(4):713–7. Kao HK, Lee WC, Yang WE, Chang CH. The posterior intrafocal pin improves sagittal alignment in Gartland type III paediatric supracondylar humeral fractures. Injury. 2016;47(4):842–7. Silva M, Pandarinath R, Farng E, Park S, Caneda C, Fong YJ, Penman A. Inter- and intra-observer reliability of the Baumann angle of the humerus in children with supracondylar humeral fractures. Int Orthop. 2010;34(4):553–7. Sato K, Mimata Y, Takahashi G, Murakami K, Ouchi S, Shiraishi H, Numata N, Doita M. Validity of the distance between the anterior humeral line and capitellum as a quantitative measure of supracondylar humeral fracture in children. Injury. 2020;51(6):1321–5. Spencer HT, Wong M, Fong YJ, Penman A, Silva M. Prospective longitudinal evaluation of elbow motion following pediatric supracondylar humeral fractures. J Bone Joint Surg Am. 2010;92(4):904–10. LiBrizzi CL, Klyce W, Ibaseta A, Shannon C, Lee RJ. Sex-based differences in pediatric supracondylar humerus fractures. Med (Baltim). 2020;99(20):e20267. Holt JB, Glass NA, Shah AS. Understanding the Epidemiology of Pediatric Supracondylar Humeral Fractures in the United States: Identifying Opportunities for Intervention. J Pediatr Orthop. 2018;38(5):e245–51. Wu JP, Lu YT, Wei XX, Zou PX, Li YQ, Liu YZ, Canavese F, Xu HW. Epidemiological characteristics and distribution of pediatric supracondylar fractures in South China: a retrospective analysis of 760 cases. J Pediatr Orthop B. 2024;33(2):136–41. Bekmez S, Camp MW, Ling R, El-Amiri N, Howard AW. Supracondylar Humerus Fractures in Older Children: Success of Closed Reduction and Percutaneous Pinning. J Pediatr Orthop. 2021;41(4):242–8. Ausó-Pérez JR, Rodríguez-Blanes GM. Comprehensive Analysis of Pediatric Supracondylar Fractures in the Emergency Department; A Single Center Experience. Bull Emerg Trauma. 2020;8(3):142–7. Beck JD, Riehl JT, Moore BE, Deegan JH, Sartorius J, Graham J, Mirenda WM. Risk factors for failed closed reduction of pediatric supracondylar humerus fractures. Orthopedics. 2012;35(10):e1492–1496. Sun LJ, Wu ZP, Yang J, Tian NF, Yu XB, Hu W, Guo XS, Chen H. Factors associated with a failed closed reduction for supracondylar fractures in children. Orthop Traumatol Surg Res. 2014;100(6):621–4. Pretell Mazzini J, Rodriguez Martin J, Andres Esteban EM. Surgical approaches for open reduction and pinning in severely displaced supracondylar humerus fractures in children: a systematic review. J Child Orthop. 2010;4(2):143–52. Ondina AB, Haidar LA, Goldberg B, Mansour A 3rd, Younas S, Siahaan J, Crawford L. Factors associated with conversion to open reduction of type 3 supracondylar humerus fractures in children. J Clin Orthop Trauma. 2022;30:101893. Wilks DJ, Ye X, Biggins R, Wang KK, Wade RG, McCombe D. Median Nerve Palsy in Pediatric Supracondylar Humerus Fractures Recovers Faster With Open Than Closed Reduction. J Pediatr Orthop. 2023;43(7):407–13. Transtrum MB, Sanchez D, Griffith S, Godinez B, Singh V, Klahs KJ, Abdelgawad A, Thabet AM. Predictors Associated with the Need for Open Reduction of Pediatric Supracondylar Humerus Fractures: A Meta-analysis of the Recent Literature. JB JS Open Access 2024, 9(3). Tables Table 1: Demographic and Clinical Data of Pediatric Extension-type Supracondylar Humerus Fractures (2016-2022) Variable 2016 2017 2018 2019 2020 2021 2022 Gender (Days) Male 68 80 98 96 93 80 100 Female 34 65 48 65 47 40 67 Age (Days) 0-2 years 19 20 24 23 16 11 8 3-5 years 31 60 52 44 57 29 59 6-8 years 29 41 48 74 43 52 71 9-11 years 18 19 11 18 16 24 23 12+ years 5 5 11 2 8 4 6 BMI (Days) Normal 80 122 122 130 110 97 139 Overweight 12 5 7 9 8 8 11 Obese 10 18 17 22 22 15 17 Season (Days) Spring 29 39 43 42 49 31 50 Summer 30 46 44 69 41 45 55 Autumn 32 48 41 35 33 33 45 Winter 11 12 18 15 17 11 17 Side (Days) Left 49 77 74 97 74 69 88 Right 53 68 72 64 66 51 79 Extension-Type (Days) 102 145 146 161 140 120 167 Gardland II 44 71 68 78 63 55 76 Gardland III 58 74 78 83 77 65 91 Time from injury to surgery (Days) 4.2 3.7 3.6 4.5 4.3 4.3 3.7 Associated injurie (Days) 11 12 13 16 13 17 23 Brachial Artery Injury 3 5 4 4 3 4 4 Median Nerve Injury 8 5 8 5 11 4 9 Radial Nerve Injury 3 4 2 6 1 7 9 Ulnar Nerve Injury 0 1 0 0 0 0 0 Other Fractures 0 2 2 5 1 3 3 Reduction Method (Days) Closed Reduction 86 131 132 148 129 114 159 Open Reduction 16 14 14 13 11 6 8 Table 2: Univariate Analysis of Risk Factors for Closed Reduction Failure in Pediatric Extension-type Supracondylar Humeral Fractures Variable Closed Reduction （ n=899 ） Open Reduction （ n=82 ） P Value Age（years） 5.05±2.61 6.20±3.01 0.05 -Male 557 58 -Female 342 24 BMI（kg/m 2 ） 15.92±2.60 16.19±2.86 >0.05 Gartland Classification <0.05 -Gartland II 450 13 -Gartland III 449 69 Concomitant Injuries <0.05 -Yes 80 25 -No 819 57 Fracture Displacement 0.05 Side of Fracture >0.05 -Left Side 486 42 -Right Side 413 40 Table 3: Multivariate Logistic Regression Analysis of Risk Factors for Closed Reduction Failure in Pediatric Extension-type Supracondylar Humeral Fractures Variable B Value SE OR Value 95%CI P Value Age 0.995 0.136 2.705 2.07-3.53 <0.05 Gartland Classification 1.619 0.336 5.048 2.61-9.76 <0.05 Concomitant Injuries -1.050 0.300 0.350 0.19-0.63 <0.05 Fracture Displacement 0.712 0.172 2.038 1.46-2.85 <0.05 Constant -8.763 1.100 0.000 - <0.05 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 21 May, 2025 Reviews received at journal 26 Apr, 2025 Reviewers agreed at journal 26 Apr, 2025 Reviews received at journal 22 Apr, 2025 Reviewers agreed at journal 17 Apr, 2025 Reviewers invited by journal 16 Apr, 2025 Editor assigned by journal 09 Apr, 2025 Editor invited by journal 20 Mar, 2025 Submission checks completed at journal 20 Mar, 2025 First submitted to journal 20 Mar, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6238231","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":447560523,"identity":"4d5da7c1-32fe-4b0e-91a6-cd682267f0bb","order_by":0,"name":"Qinqin Li","email":"","orcid":"","institution":"Second Hospital of Hebei Medical University","correspondingAuthor":false,"prefix":"","firstName":"Qinqin","middleName":"","lastName":"Li","suffix":""},{"id":447560524,"identity":"4d12bbd4-b55d-44fa-a5a4-3b24bd3fcd60","order_by":1,"name":"Yuchang Dong","email":"","orcid":"","institution":"Hebei University of Chinese Medicine","correspondingAuthor":false,"prefix":"","firstName":"Yuchang","middleName":"","lastName":"Dong","suffix":""},{"id":447560525,"identity":"3751c57b-308a-42be-8903-838e9041e3f2","order_by":2,"name":"Ye Li","email":"","orcid":"","institution":"Third Hospital of Hebei Medical University","correspondingAuthor":false,"prefix":"","firstName":"Ye","middleName":"","lastName":"Li","suffix":""},{"id":447560526,"identity":"145260f8-f75f-4942-9244-e36f87d9a12d","order_by":3,"name":"Qingbing He","email":"","orcid":"","institution":"Third Hospital of Hebei Medical University","correspondingAuthor":false,"prefix":"","firstName":"Qingbing","middleName":"","lastName":"He","suffix":""},{"id":447560527,"identity":"bc88a033-5e4f-41ca-8497-bb60a5069aa2","order_by":4,"name":"Jinchao Cao","email":"","orcid":"","institution":"Third Hospital of Hebei Medical University","correspondingAuthor":false,"prefix":"","firstName":"Jinchao","middleName":"","lastName":"Cao","suffix":""},{"id":447560528,"identity":"baaf5112-472b-491f-bda9-8ec47821948c","order_by":5,"name":"Jiuhui Han","email":"","orcid":"","institution":"Third Hospital of Hebei Medical University","correspondingAuthor":false,"prefix":"","firstName":"Jiuhui","middleName":"","lastName":"Han","suffix":""},{"id":447560530,"identity":"f5343d5c-47a1-4fe2-8e9e-f065d38f898e","order_by":6,"name":"Dongxiao Xie","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABDklEQVRIiWNgGAWjYFACxgYE+4OBhB0/M/PBB0RrYZxRYZEs2c6WbEC0hcw8ZyoYN5znMRPAp0p+dnPbgw9/DufLuzcfe8DbJsFsfJjBjIGhxiYalxaDOwfbDWe2HbbceOZYuoFkmwSf2WGGtAcMx9JyG3BpkUhsk+ZtOGxgOCPHTMIQaAtQy3EDxobDOLXIzwBq+fMHqGX+GzOgdgnGzc2MQBKPFoYbQC0MbIcN5CV4zCQOnJFg3MDMzIZXC9AvbZK9bekGBjxpaZINFRLJEofZmA0S8PhFfnb7M4kff6wN5NsPH5P+Y1Bnx99//uODDzU2uB0mAbPuALJoAi7lyFrkcRo6CkbBKBgFIx4AAGM0WgiYleOoAAAAAElFTkSuQmCC","orcid":"","institution":"Third Hospital of Hebei Medical University","correspondingAuthor":true,"prefix":"","firstName":"Dongxiao","middleName":"","lastName":"Xie","suffix":""},{"id":447560531,"identity":"1f0f444c-6b37-450d-91fe-641db28a5394","order_by":7,"name":"Yazhou Li","email":"","orcid":"","institution":"Third Hospital of Hebei Medical University","correspondingAuthor":false,"prefix":"","firstName":"Yazhou","middleName":"","lastName":"Li","suffix":""}],"badges":[],"createdAt":"2025-03-16 14:53:08","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6238231/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6238231/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":82120007,"identity":"b2d67125-a5eb-4ca6-94e2-6b2a82f7b9cf","added_by":"auto","created_at":"2025-05-07 03:12:52","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":29047,"visible":true,"origin":"","legend":"\u003cp\u003eTrend Chart of Age Distribution in Pediatric Extension-Type Supracondylar Humerus Fractures at a Regional General Hospital\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6238231/v1/d66321d112ede6f57daf1ddd.jpg"},{"id":82120005,"identity":"aadb006a-6c33-48a0-bd94-166b2cba7974","added_by":"auto","created_at":"2025-05-07 03:12:52","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":33983,"visible":true,"origin":"","legend":"\u003cp\u003eGender Distribution of Pediatric Extension-Type Supracondylar Humerus Fractures Across Different Age Groups\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6238231/v1/c96176af176eba9e476169d9.jpg"},{"id":82117951,"identity":"951e627f-5932-4e04-ba5a-6205c80c9319","added_by":"auto","created_at":"2025-05-07 03:04:52","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":27488,"visible":true,"origin":"","legend":"\u003cp\u003eTrend of Closed Reduction Rates for Pediatric Extension-Type Supracondylar Humerus Fractures from 2016 to 2022\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6238231/v1/38cb2f3979ddd0fd5ed6c74f.jpg"},{"id":82122410,"identity":"d2ebcf7f-42ff-456b-a18e-97457c7018b2","added_by":"auto","created_at":"2025-05-07 03:28:52","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":917208,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6238231/v1/0ebde321-8ed2-4ebf-9736-ccbab1c7ae81.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Epidemiological Characteristics and Risk Factors for Closed Reduction Failure in Pediatric Extension-type Supracondylar Humerus Fractures: A Study from a Regional General Hospital","fulltext":[{"header":"Background","content":"\u003cp\u003eSupracondylar humerus fractures (SCHFs) represent the most common pediatric elbow fractures, accounting for up to 60% of all elbow injuries in children [\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Among these, extension-type fractures, typically caused by a fall on an outstretched hand, are the predominant sub-type. Although closed reduction and percutaneous pinning (CRPP) is widely regarded as the standard treatment for displaced extension-type SCHFs [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e], closed reduction failure remains a significant clinical concern. Failed closed reduction often necessitates more invasive procedures, such as open reduction, and increases the risk of complications, including infection, scar formation, neurovascular injury, malunion, and long-term functional deficits [\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003cp\u003ePrevious studies have explored potential risk factors for closed reduction failure in pediatric extension-type SCHFs, including fracture severity, delayed treatment, and surgeon experience. Nevertheless, comprehensive data on epidemiological characteristics and risk factors remain scarce, with existing findings often inconsistent and limited by small sample sizes [\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Moreover, regional variations in the incidence and management of these fractures have not been thoroughly investigated, despite their potential impact on clinical outcomes.\u003c/p\u003e \u003cp\u003eThis study aims to address these gaps by analyzing the epidemiological characteristics and identifying risk factors for closed reduction failure in pediatric extension-type SCHFs within a regional general hospital setting. By examining a large, homogeneous patient cohort, we seek to generate robust evidence that can inform clinical decision-making and refine the management of these common yet complex injuries.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003e\u003cstrong\u003eStudy population\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis retrospective study analyzed the case data of 981 pediatric patients with extension-type SCHFs admitted to the Pediatric Orthopedic Department of Third Hospital of Hebei Medical University between January 2016 and December 2022. Inclusion criteria were as follows: (1) a diagnosis of extension-type SCHFs requiring surgical treatment; (2) availability of complete clinical and imaging data; (3) treatment exclusively received at our hospital; and (4) age \u0026lt; 18 years at the time of injury. Exclusion criteria included: (1) incomplete data; (2) missing clinical or imaging data; (3) presence of congenital or severe systemic diseases (e.g., pathological fractures); and (4) treatment at other medical institutions. The study was approved by the Ethics Committee of the Third Hospital of Hebei Medical University, and stringent measures were taken to ensure patient privacy.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData collection\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData collected included patient demographics (age, gender, height, and weight), clinical characteristics (fracture laterality, presence of complications, fracture type, and classification), and surgical details (time from injury to surgery and reduction method). Body mass index (BMI) was calculated as weight (kg) divided by height squared (m²). Extension-type fractures were further categorized using the Gartland classification: Type I (non-displaced), Type II (displaced with intact posterior cortex), and Type III (displaced with no cortical contact). In anteroposterior elbow radiographs, displacement of the fracture was recorded. Complications included nerve injuries, vascular injuries, and concomitant fractures. Surgical reduction methods were classified as either closed reduction or open reduction, with open reduction cases defined as closed reduction failures.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eGrouping and study design\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study employed a retrospective case-control design. Univariate and multivariate regression analyses were performed to identify potential risk factors for closed reduction failure. BMI was compared with age- and gender-matched reference values, with BMI \u0026gt;85th percentile classified as overweight and BMI \u0026gt;95th percentile as obese. Based on the season of injury, patients were categorized into four groups: Spring (March to May), Summer (June to August), Autumn (September to November), and Winter (December to February). Additional groupings were established based on fracture classification. In anteroposterior elbow radiographs, fractures without displacement are classified as the normal group, those with posteromedial displacement as the ulnar deviation group, and those with posterolateral displacement as the radial deviation group.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData analysis was conducted using SPSS 26.0 statistical software. Quantitative data are expressed as mean ± standard deviation (x̄ ± s), and group comparisons were performed using independent samples t-tests. Qualitative data are presented as frequencies and percentages, with group comparisons made using chi-square tests. The Shapiro-Wilk test was used to assess the normality of data distribution. For normally distributed variables, t-tests were used, while the Mann-Whitney U test was applied for non-normally distributed variables. The relationships between factors such as age, gender, fracture type, BMI, and closed reduction failure rates were analyzed using one-way ANOVA or chi-square tests. Factors identified through screening were further analyzed using logistic regression models, with statistical significance set at P \u0026lt; 0.05.\u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eFrom January 2016 to December 2022, a total of 981 pediatric patients diagnosed with extension-type SCHFs met the inclusion criteria. Of these, 615 were male (62.69%) and 366 were female (37.31%). The fractures were located on the left side in 528 cases (53.82%) and on the right side in 453 cases (46.18%). According to the Gartland classification, 455 cases (46.38%) were classified as Type II, while 526 cases (53.62%) were Type III. Associated injuries were present in 105 patients (10.70%), including median nerve injury in 50 cases (5.10%), radial nerve injury in 32 cases (3.26%), brachial artery injury in 27 cases (2.75%), concomitant fractures in 16 cases (1.63%), and ulnar nerve injury in 1 case (0.10%). Notably, some patients exhibited multiple associated injuries (Table 1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAge Distribution\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn Shijiazhuang and surrounding areas of Hebei Province, the incidence of SCHFs followed a characteristic \"rise-and-fall\" pattern. The peak incidence occurred at five years of age, with a high-incidence plateau observed between three and seven years. After the age of eight, the incidence rate declined markedly, with only four cases reported in children aged 13 years or older (Figure 1). The mean age of the study population was 4.04\u0026nbsp;±\u0026nbsp;2.61 years (range: 6 months to 14 years).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eGender Characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMales were significantly more affected than females (615 vs. 366 cases, 63% vs. 37%; P \u0026lt; 0.05). The male predominance was evident across all age groups, with the most pronounced gender disparities observed in the 6–8 and 9–11-year age groups. The highest incidence among males occurred in the 6–8-year group (220 cases), whereas females exhibited a smaller peak at 3–5 years (151 cases). However, at all ages, the incidence remained consistently lower in females compared to males (Figure 2).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eBMI Distribution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe mean BMI of the study population was 15.94\u0026nbsp;±\u0026nbsp;2.62 kg/m². Based on weight classification, 800 patients (81.55%) had normal weight, 121 (12.33%) were classified as obese, and 60 (6.12%) were overweight. Among patients with Gartland II fractures, 371 (37.82%) had normal weight, 63 (6.42%) were obese, and 29 (2.96%) were overweight. In contrast, among those with Gartland III fractures, 429 (43.73%) had normal weight, 58 (5.91%) were obese, and 31 (3.16%) were overweight. No significant differences were observed in fracture type distribution across different weight categories (P \u0026gt; 0.05) (Table 1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMonthly and Seasonal Distribution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe number of cases showed a clear seasonal pattern, gradually increasing from January, peaking in May (136 cases), and subsequently declining to the lowest point in December (25 cases). The highest incidence was recorded in spring (March–May, 283 cases) and summer (June–August, 330 cases), with May representing the annual peak. Conversely, the lowest incidence was observed in winter (December–February, 101 cases). These seasonal variations may be associated with environmental factors such as temperature and humidity, as well as changes in children's activity patterns, although further investigation is warranted.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eUnivariate Analysis of Closed Reduction Failure\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eClosed reduction is widely accepted as the standard treatment for extension-type SCHFs. In this cohort, the overall success rate of closed reduction was 91.64% (899 cases), significantly higher than the failure rate of 8.36% (82 cases) (P \u0026lt; 0.05) (Figure 3). Univariate analysis identified age, Gartland classification, the presence of concomitant injuries, and fracture displacement as significant factors associated with closed reduction failure (P \u0026lt; 0.05). However, no significant association was found between failure rates and gender, BMI, or fracture laterality (P \u0026gt; 0.05) (Table 2).\u003c/p\u003e\n\u003cp\u003ePatients in the closed reduction group were significantly younger (5.05\u0026nbsp;±\u0026nbsp;2.61 years) compared to those requiring open reduction (6.20\u0026nbsp;±\u0026nbsp;3.01 years) (P \u0026lt; 0.05). The failure rate of closed reduction was significantly higher in patients with Gartland III fractures compared to Gartland II fractures (P \u0026lt; 0.05). Additionally, the failure rate was substantially higher in patients with associated injuries (23.81%) compared to those without (6.51%) (P \u0026lt; 0.05). Regarding fracture displacement, cases with radial deviation had a significantly higher closed reduction failure rate (17.00%) compared to those with ulnar deviation (6.79%) or no displacement (4.10%) (P \u0026lt; 0.05). Neither gender, BMI, nor fracture laterality (left vs. right) significantly influenced the reduction outcome (P \u0026gt; 0.05).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMultivariate Logistic Regression Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMultivariate logistic regression analysis identified age, Gartland classification, and fracture displacement as significant independent risk factors for closed reduction failure. The odds ratios (OR) were 2.705 (95% CI: [2.07, 3.53]), 5.048 (95% CI: [2.61, 9.76]), and 2.038 (95% CI: [1.46, 2.85]), respectively (P \u0026lt; 0.001 for all). In contrast, the absence of concomitant injuries was identified as a protective factor, reducing the risk of closed reduction failure by 65% (OR = 0.350, 95% CI: [0.19, 0.63], P \u0026lt; 0.001). These findings underscore the importance of considering patient age, fracture severity (Gartland classification and displacement direction), and associated injuries when formulating treatment strategies for pediatric extension-type SCHFs (Table 3).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eSupracondylar humerus fractures (SCHFs) are the most common pediatric elbow fractures, with extension-type fractures being the most prevalent [1-3]. Despite advancements in treatment, closed reduction failure remains a significant challenge, often necessitating open reduction and increasing the risks of infection, neurovascular injury, and long-term functional impairments [5-7]. This study investigates the epidemiological characteristics and identifies risk factors for closed reduction failure in pediatric extension-type SCHFs in a regional hospital setting, providing evidence-based insights to enhance clinical management and improve patient outcomes.\u003c/p\u003e\n\u003cp\u003eOur cohort of 981 patients exhibited a male predominance (63%), consistent with previous studies reporting higher SCHF rates in boys, likely due to their greater involvement in high-risk activities and sports [12]. The peak incidence occurred at five years of age, with a high-incidence plateau between three and seven years [13], coinciding with the period when children are most active and susceptible to falls [14]. This observation aligns with existing literature suggesting that younger children are more vulnerable to SCHFs due to weaker bones and higher activity levels [15]. The incidence decreased after the age of eight, likely due to improved motor skills, greater bone strength, and reduced risk-taking behavior [15].\u003c/p\u003e\n\u003cp\u003eIn the regions of China , the climate is characterized by four distinct seasons. In the incidence of SCHFs, seasonal variations were also observed, with peaks in spring and summer, likely due to increased outdoor activities during warmer months. This finding is consistent with previous studies linking seasonal changes in physical activity to higher pediatric fracture rates. For example, Ausó-Pérez et al. [16] reported an increased incidence of pediatric fractures during warmer months, correlating with heightened outdoor play. These findings highlight the importance of preventive strategies, such as parental supervision and safety education, particularly during high-incidence periods and among high-risk populations.\u003c/p\u003e\n\u003cp\u003eSeveral significant risk factors for closed reduction failure were identified in this study, including older age, higher Gartland classification (Type III fractures), and fracture displacement (particularly radial displacement). These findings align with previous research indicating that more severe fractures are more challenging to reduce due to greater soft tissue interposition, instability, and difficulties in achieving anatomical alignment [17, 18]. Gartland Type III fractures have been independently associated with an increased risk of closed reduction failure [17], as severe displacement often precludes satisfactory alignment through closed reduction alone [19]. Similarly, radial displacement has been linked to higher failure rates, with Ondina et al reporting that posterolateral displacement frequently necessitates open reduction due to the difficulty in achieving stable closed reduction [20].\u003c/p\u003e\n\u003cp\u003eThe higher failure rates observed in older children may be attributed to increased bone density and reduced plasticity, which complicate reduction. Older children with SCHFs often present with more complex fracture patterns, necessitating more aggressive treatment [12]. Additionally, concomitant injuries, such as neurovascular damage, were associated with higher failure rates due to increased fracture complexity and the need for more extensive surgical intervention. These findings are consistent with previous studies demonstrating that concomitant injuries significantly raise the likelihood of open reduction [18, 20, 21].\u003c/p\u003e\n\u003cp\u003eMoreover, the increased failure rate of closed reduction in patients with concomitant injuries aligns with prior findings [18], suggesting that complex fracture displacement and soft tissue interposition significantly heighten reduction difficulty. The association between neurovascular injuries and the need for open reduction further emphasizes the importance of early identification of high-risk cases to optimize treatment strategies [18, 20-22].\u003c/p\u003e\n\u003cp\u003eInterestingly, gender, BMI, and fracture laterality (left vs. right) did not significantly influence closed reduction outcomes. This finding contrasts with some previous studies suggesting that obesity may complicate fracture reduction [22]. However, Ondina et al. found no significant association between BMI and closed reduction success in pediatric SCHFs [20]. This discrepancy may be attributable to differences in study populations or the relatively low prevalence of obesity in our cohort.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStrengths and limitations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo our knowledge, this is one of the largest single-center studies examining risk factors for closed reduction failure in pediatric extension-type SCHFs. However, the retrospective design limits the ability to establish causal relationships, and the single-center nature may restrict the generalizability of findings. Additionally, factors such as surgeon experience and potential confounders, including injury timing and comorbidities, were not analyzed and warrant further investigation. The low prevalence of obesity in our cohort may explain the lack of a significant association between BMI and closed reduction failure, underscoring the need for studies in more diverse populations.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eExtension-type SCHFs are most prevalent among preschool-aged children, particularly 5-year-old boys, with peak incidence occurring in spring and summer. Older age, higher Gartland classification, concomitant injuries, and radial displacement are significant independent risk factors for closed reduction failure. These findings highlight the necessity of individualized treatment strategies to optimize outcomes in pediatric SCHFs management and minimize the need for invasive interventions.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eBMI \u0026nbsp; \u0026nbsp; \u0026nbsp; Body Mass Index\u003c/p\u003e\n\u003cp\u003eCI \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Confidence Interval\u003c/p\u003e\n\u003cp\u003eCRPP: \u0026nbsp; \u0026nbsp; Closed Reduction and Percutaneous Pinning\u003c/p\u003e\n\u003cp\u003eOR \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Odds Ratio\u003c/p\u003e\n\u003cp\u003eSCHFs \u0026nbsp; \u0026nbsp; Supracondylar Humerus Fractures\u003c/p\u003e\n\u003cp\u003eANOVA \u0026nbsp; \u0026nbsp;Analysis of Variance\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors would like to thank all the research assistants who helped support and collect the data used for the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026ldquo;DX\u0026rdquo; and \u0026ldquo;QL\u0026rdquo;designed the study and drafted the manuscript. \u0026ldquo;YD\u0026rdquo; performed statistical analyses. \u0026ldquo;YL\u0026rdquo;, \u0026ldquo;QH\u0026rdquo;, and \u0026ldquo;JC\u0026rdquo; contributed to data collection and interpretation. \u0026ldquo;JH\u0026rdquo; and \u0026ldquo;ZL\u0026rdquo; supervised the research and critically revised the manuscript. All authors reviewed the final draft of the study and approved it for publication. All authors agree to be personally accountable for the submitted literature.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo funding or sponsorship was received for this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\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\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study was started after approval by Ethics Committee of the Third Hospital of Hebei Medical University and Approval Number KE-2025-009-1. Informed consent was obtained from legal guardians of the subjects enrolled in the study. This study was performed in accordance with the Declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot Applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor details\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e1\u003c/sup\u003eDepartment of Pediatric Orthopedics, Third Hospital of Hebei Medical University, Shijiazhuang City, China.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e2\u003c/sup\u003eDepartment of Pediatric Surgery, Second Hospital of Hebei Medical University, Shijiazhuang City, China.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003e3\u003c/sup\u003eHebei University of Chinese Medicine, Shijiazhuang City, China.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eZorrilla SdNJ, Prada-Ca\u0026ntilde;izares A, Marti-Ciruelos R, Pretell-Mazzini J. Supracondylar humeral fractures in children: current concepts for management and prognosis. Int Orthop. 2015;39(11):2287\u0026ndash;96.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePennock AT, Charles M, Moor M, Bastrom TP, Newton PO. Potential causes of loss of reduction in supracondylar humerus fractures. J Pediatr Orthop. 2014;34(7):691\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSaeed W, Waseem M. Elbow Fractures Overview. StatPearls. edn. Treasure Island (FL) ineligible companies. Disclosure: Muhammad Waseem declares no relevant financial relationships with ineligible companies.: StatPearls Publishing Copyright \u0026copy; 2024. StatPearls Publishing LLC.; 2024.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTomaszewski R, Pethe K, Kler J, Rutz E, Mayr J, Dajka J. Supracondylar Fractures of the Humerus: Association of Neurovascular Lesions with Degree of Fracture Displacement in Children-A Retrospective Study. Child (Basel) 2022, 9(3).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDuffy S, Flannery O, Gelfer Y, Monsell F. Overview of the contemporary management of supracondylar humeral fractures in children. Eur J Orthop Surg Traumatol. 2021;31(5):871\u0026ndash;81.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBabal JC, Mehlman CT, Klein G. Nerve injuries associated with pediatric supracondylar humeral fractures: a meta-analysis. J Pediatr Orthop. 2010;30(3):253\u0026ndash;63.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSankar WN, Hebela NM, Skaggs DL, Flynn JM. Loss of pin fixation in displaced supracondylar humeral fractures in children: causes and prevention. J Bone Joint Surg Am. 2007;89(4):713\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKao HK, Lee WC, Yang WE, Chang CH. The posterior intrafocal pin improves sagittal alignment in Gartland type III paediatric supracondylar humeral fractures. Injury. 2016;47(4):842\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSilva M, Pandarinath R, Farng E, Park S, Caneda C, Fong YJ, Penman A. Inter- and intra-observer reliability of the Baumann angle of the humerus in children with supracondylar humeral fractures. Int Orthop. 2010;34(4):553\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSato K, Mimata Y, Takahashi G, Murakami K, Ouchi S, Shiraishi H, Numata N, Doita M. Validity of the distance between the anterior humeral line and capitellum as a quantitative measure of supracondylar humeral fracture in children. Injury. 2020;51(6):1321\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSpencer HT, Wong M, Fong YJ, Penman A, Silva M. Prospective longitudinal evaluation of elbow motion following pediatric supracondylar humeral fractures. J Bone Joint Surg Am. 2010;92(4):904\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLiBrizzi CL, Klyce W, Ibaseta A, Shannon C, Lee RJ. Sex-based differences in pediatric supracondylar humerus fractures. Med (Baltim). 2020;99(20):e20267.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHolt JB, Glass NA, Shah AS. Understanding the Epidemiology of Pediatric Supracondylar Humeral Fractures in the United States: Identifying Opportunities for Intervention. J Pediatr Orthop. 2018;38(5):e245\u0026ndash;51.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWu JP, Lu YT, Wei XX, Zou PX, Li YQ, Liu YZ, Canavese F, Xu HW. Epidemiological characteristics and distribution of pediatric supracondylar fractures in South China: a retrospective analysis of 760 cases. J Pediatr Orthop B. 2024;33(2):136\u0026ndash;41.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBekmez S, Camp MW, Ling R, El-Amiri N, Howard AW. Supracondylar Humerus Fractures in Older Children: Success of Closed Reduction and Percutaneous Pinning. J Pediatr Orthop. 2021;41(4):242\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAus\u0026oacute;-P\u0026eacute;rez JR, Rodr\u0026iacute;guez-Blanes GM. Comprehensive Analysis of Pediatric Supracondylar Fractures in the Emergency Department; A Single Center Experience. Bull Emerg Trauma. 2020;8(3):142\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBeck JD, Riehl JT, Moore BE, Deegan JH, Sartorius J, Graham J, Mirenda WM. Risk factors for failed closed reduction of pediatric supracondylar humerus fractures. Orthopedics. 2012;35(10):e1492\u0026ndash;1496.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSun LJ, Wu ZP, Yang J, Tian NF, Yu XB, Hu W, Guo XS, Chen H. Factors associated with a failed closed reduction for supracondylar fractures in children. Orthop Traumatol Surg Res. 2014;100(6):621\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePretell Mazzini J, Rodriguez Martin J, Andres Esteban EM. Surgical approaches for open reduction and pinning in severely displaced supracondylar humerus fractures in children: a systematic review. J Child Orthop. 2010;4(2):143\u0026ndash;52.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOndina AB, Haidar LA, Goldberg B, Mansour A 3rd, Younas S, Siahaan J, Crawford L. Factors associated with conversion to open reduction of type 3 supracondylar humerus fractures in children. J Clin Orthop Trauma. 2022;30:101893.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWilks DJ, Ye X, Biggins R, Wang KK, Wade RG, McCombe D. Median Nerve Palsy in Pediatric Supracondylar Humerus Fractures Recovers Faster With Open Than Closed Reduction. J Pediatr Orthop. 2023;43(7):407\u0026ndash;13.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTranstrum MB, Sanchez D, Griffith S, Godinez B, Singh V, Klahs KJ, Abdelgawad A, Thabet AM. Predictors Associated with the Need for Open Reduction of Pediatric Supracondylar Humerus Fractures: A Meta-analysis of the Recent Literature. JB JS Open Access 2024, 9(3).\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable 1: Demographic and Clinical Data of Pediatric Extension-type Supracondylar Humerus Fractures (2016-2022)\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"535\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 209px;\"\u003e\n \u003cp\u003eVariable\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 49px;\"\u003e\n \u003cp\u003e2016\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 43px;\"\u003e\n \u003cp\u003e2017\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e2018\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e2019\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 46px;\"\u003e\n \u003cp\u003e2020\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e2021\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e2022\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003eGender\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;(Days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e100\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e67\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"5\" valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;(Days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e0-2 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e3-5 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e59\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e6-8 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e71\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e9-11 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003e12+ years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003eBMI\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e(Days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eNormal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e122\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e122\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e130\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e110\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e139\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eOverweight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eObese\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"4\" valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSeason\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;(Days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eSpring\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e50\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eSummer\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e55\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eAutumn\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e45\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eWinter\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003eSide\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;(Days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eLeft\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e88\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eRight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e79\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 209px;\"\u003e\n \u003cp\u003eExtension-Type (Days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 49px;\"\u003e\n \u003cp\u003e102\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 43px;\"\u003e\n \u003cp\u003e145\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e146\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e161\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 46px;\"\u003e\n \u003cp\u003e140\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e120\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e167\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 209px;\"\u003e\n \u003cp\u003eGardland II\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 49px;\"\u003e\n \u003cp\u003e44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 43px;\"\u003e\n \u003cp\u003e71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 46px;\"\u003e\n \u003cp\u003e63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e76\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 209px;\"\u003e\n \u003cp\u003eGardland III\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 49px;\"\u003e\n \u003cp\u003e58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 43px;\"\u003e\n \u003cp\u003e74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 46px;\"\u003e\n \u003cp\u003e77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e91\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 209px;\"\u003e\n \u003cp\u003eTime from injury to surgery (Days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 49px;\"\u003e\n \u003cp\u003e4.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 43px;\"\u003e\n \u003cp\u003e3.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e3.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e4.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 46px;\"\u003e\n \u003cp\u003e4.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e4.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e3.7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 209px;\"\u003e\n \u003cp\u003eAssociated injurie (Days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 49px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 43px;\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 46px;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 209px;\"\u003e\n \u003cp\u003eBrachial Artery Injury\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 49px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 43px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 46px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 209px;\"\u003e\n \u003cp\u003eMedian Nerve Injury\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 49px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 43px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 46px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 209px;\"\u003e\n \u003cp\u003eRadial Nerve Injury\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 49px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 43px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 46px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 209px;\"\u003e\n \u003cp\u003eUlnar Nerve Injury\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 49px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 43px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 46px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 209px;\"\u003e\n \u003cp\u003eOther Fractures\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 49px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 43px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 51px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 46px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 50px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003eReduction Method (Days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eClosed Reduction\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e131\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e132\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e148\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e129\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e114\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e159\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 114px;\"\u003e\n \u003cp\u003eOpen Reduction\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 49px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 43px;\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 42px;\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 51px;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 46px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 50px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 44px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eTable 2: Univariate Analysis of Risk Factors for Closed Reduction Failure in Pediatric Extension-type Supracondylar Humeral Fractures\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eClosed Reduction\u003c/strong\u003e\u003cstrong\u003e（\u003c/strong\u003e\u003cstrong\u003en=899\u003c/strong\u003e\u003cstrong\u003e）\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOpen Reduction\u003c/strong\u003e\u003cstrong\u003e（\u003c/strong\u003e\u003cstrong\u003en=82\u003c/strong\u003e\u003cstrong\u003e）\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eAge（years）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e5.05\u0026plusmn;2.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e6.20\u0026plusmn;3.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eGender\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026gt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e-Male\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e557\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e-Female\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e342\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eBMI（kg/m\u003csup\u003e2\u003c/sup\u003e）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e15.92\u0026plusmn;2.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e16.19\u0026plusmn;2.86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026gt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eGartland Classification\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e-Gartland II\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e450\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e-Gartland III\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e449\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eConcomitant Injuries\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e-Yes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e-No\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e819\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eFracture Displacement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e-Radial Displacement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e205\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e-Ulnar Displacement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e343\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e-No Displacement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e351\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eTime to Surgery（Days）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e3.99\u0026plusmn;2.49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e4.51\u0026plusmn;3.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026gt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eSide of Fracture\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026gt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e-Left Side\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e486\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e-Right Side\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 172px;\"\u003e\n \u003cp\u003e413\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eTable 3: Multivariate Logistic Regression Analysis of Risk Factors for Closed Reduction Failure in Pediatric Extension-type Supracondylar Humeral Fractures\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eB Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 83px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSE\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 89px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOR Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 77px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95%CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003e0.995\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 83px;\"\u003e\n \u003cp\u003e0.136\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 89px;\"\u003e\n \u003cp\u003e2.705\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 77px;\"\u003e\n \u003cp\u003e2.07-3.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eGartland Classification\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003e1.619\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 83px;\"\u003e\n \u003cp\u003e0.336\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 89px;\"\u003e\n \u003cp\u003e5.048\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 77px;\"\u003e\n \u003cp\u003e2.61-9.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eConcomitant Injuries\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003e-1.050\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 83px;\"\u003e\n \u003cp\u003e0.300\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 89px;\"\u003e\n \u003cp\u003e0.350\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 77px;\"\u003e\n \u003cp\u003e0.19-0.63\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eFracture Displacement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003e0.712\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 83px;\"\u003e\n \u003cp\u003e0.172\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 89px;\"\u003e\n \u003cp\u003e2.038\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 77px;\"\u003e\n \u003cp\u003e1.46-2.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 155px;\"\u003e\n \u003cp\u003eConstant\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 91px;\"\u003e\n \u003cp\u003e-8.763\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 83px;\"\u003e\n \u003cp\u003e1.100\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 89px;\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 77px;\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026lt;0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"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":"bmc-pediatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bped","sideBox":"Learn more about [BMC Pediatrics](http://bmcpediatr.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bped/default.aspx","title":"BMC Pediatrics","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Supracondylar humerus fractures, Extension-type, Closed reduction failure, risk factors, Epidemiology","lastPublishedDoi":"10.21203/rs.3.rs-6238231/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6238231/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eSupracondylar humerus fractures (SCHFs) are the most common pediatric elbow fractures, with extension-type fractures being the predominant subtype. While closed reduction and percutaneous pinning (CRPP) is the standard treatment for displaced extension-type SCHFs, failure of closed reduction remains a significant concern. Such failures often necessitate more invasive procedures and are associated with increased complications. Although previous studies have explored potential risk factors for closed reduction failure, comprehensive epidemiological data and consistent conclusions remain limited. This study aims to analyze the epidemiological characteristics and identify risk factors for closed reduction failure in pediatric extension-type SCHFs at a regional general hospital, providing evidence to enhance clinical management strategies.\u003c/p\u003e\u003ch2\u003eStudy design\u003c/h2\u003e \u003cp\u003eA retrospective analysis was conducted on 981 pediatric patients diagnosed with extension-type SCHFs and treated at Third Hospital of Hebei Medical University between January 2016 and December 2022. Data on patient demographics, clinical characteristics, and surgical details were collected. Univariate and multivariate logistic regression analyses were performed to identify risk factors for closed reduction failure.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eAmong the study cohort, 615 patients (62.69%) were male and 366 (37.31%) were female, with a mean age of 4.04\u0026thinsp;\u0026plusmn;\u0026thinsp;2.61 years. The peak incidence was observed at five years of age, with a high-incidence plateau between three and seven years. Seasonal variations were noted, with a higher incidence in spring and summer. The overall success rate of closed reduction was 91.64%, whereas the failure rate was 8.36%. Multivariate logistic regression identified several significant independent risk factors for closed reduction failure: older age (OR\u0026thinsp;=\u0026thinsp;2.705, 95% CI: [2.07, 3.53]), higher Gartland classification (OR\u0026thinsp;=\u0026thinsp;5.048, 95% CI: [2.61, 9.76]), radial displacement (OR\u0026thinsp;=\u0026thinsp;2.038, 95% CI: [1.46, 2.85]), and concomitant injuries (OR\u0026thinsp;=\u0026thinsp;0.350, 95% CI: [0.19, 0.63]).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eExtension-type SCHFs are most prevalent among preschool-aged children, particularly 5-year-old boys, with peak incidence occurring in spring and summer. Older age, higher Gartland classification, concomitant injuries, and radial displacement are significant independent risk factors for closed reduction failure. These findings highlight the necessity of individualized treatment strategies to optimize outcomes in pediatric SCHFs management and minimize the need for invasive interventions.\u003c/p\u003e","manuscriptTitle":"Epidemiological Characteristics and Risk Factors for Closed Reduction Failure in Pediatric Extension-type Supracondylar Humerus Fractures: A Study from a Regional General Hospital","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-07 03:04:47","doi":"10.21203/rs.3.rs-6238231/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-05-21T08:12:18+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-27T02:48:39+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"49764008633774956844226438315626732254","date":"2025-04-26T08:11:02+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-22T20:19:23+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"138495618505505554042495437283876573538","date":"2025-04-17T07:27:52+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-04-17T03:47:17+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-04-09T16:49:20+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-03-20T20:33:58+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-03-20T14:48:39+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Pediatrics","date":"2025-03-20T14:47:29+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-pediatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bped","sideBox":"Learn more about [BMC Pediatrics](http://bmcpediatr.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bped/default.aspx","title":"BMC Pediatrics","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"6f7f6029-a80d-4d75-9702-71ac444dcd26","owner":[],"postedDate":"May 7th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-01-30T06:38:20+00:00","versionOfRecord":[],"versionCreatedAt":"2025-05-07 03:04:47","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6238231","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6238231","identity":"rs-6238231","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}