A Comparative Study of X-ray and 3D CT in the Evaluation of Pauwels Classification for Femoral Neck Fractures

A Comparative Study of X-ray and 3D CT in the Evaluation of Pauwels Classification for Femoral Neck Fractures | 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 A Comparative Study of X-ray and 3D CT in the Evaluation of Pauwels Classification for Femoral Neck Fractures Ming Sun, Hairui Liang, Tong Bai, Tianyu Zhang, Rongda Xu, siyu Duan, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5339390/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background To compare the accuracy of X-ray and 3D CT in measuring the Pauwels angle of femoral neck fractures and the reliability of these methods in guiding Pauwels classification. Methods X-ray and CT images of 40 femoral neck fracture patients from our hospital were collected. Three physicians measured the Pauwels angle on both X-ray and CT images using the PACS Workstation system, performing the measurements twice and classifying the fractures based on the Pauwels classification. Consistency and reproducibility analyses were conducted to evaluate the performance of the two methods. Results The Pauwels angles and classification results obtained by the chief physician, attending physician, and resident physician using both X-ray and CT methods showed statistically significant differences, with P values all < 0.05. For the consistency analysis, the interclass correlation coefficients (ICC) for two measurements were: for the X-ray method, ICCs of 0.712, 0.882, and 0.578 for 1vs2, 1vs3, and 2vs3, respectively, and ICCs of 0.357, 0.631, and 0.596 for the same pairs; for the CT method, ICCs of 0.935, 0.966, and 0.960 for 1vs2, 1vs3, and 2vs3, and ICCs of 0.896, 0.952, and 0.872 for the same pairs. The reproducibility analysis for the three physicians showed that the ICCs for the X-ray method were 0.767, 0.720, and 0.754, while for the CT method, the ICCs were 0.945, 0.918, and 0.964. The CT method demonstrated superior consistency and reproducibility compared to the X-ray method. Conclusions Compared to X-rays, 3D CT scanning is more accurate in measuring the Pauwels angle of femoral neck fractures and provides more reliable guidance for Pauwels classification, with higher clinical reproducibility. Therefore, it is recommended to use CT scanning instead of X-ray for preoperative evaluation of fracture stability in femoral neck fracture patients. X-ray 3D CT scan femoral neck fracture Pauwels classification Figures Figure 1 Figure 2 Figure 3 Introduction Femoral neck fractures account for approximately 3.6% of all fractures and 50% of hip fractures, with their incidence increasing annually due to rising traffic accidents and population aging [ 1 – 2 ]. Currently, elderly patients typically undergo joint replacement surgery, while younger and middle-aged patients are more often treated with internal fixation. The most common internal fixation methods for femoral neck fractures include the dynamic hip screw system and cannulated screw fixation. Depending on the type of fracture, fixation options can include three screws in a triangular configuration, four screws, or an F-shaped fixation [ 3 – 6 ]. However, patients with femoral neck fractures often face several postoperative complications, such as fixation failure, non-union, and avascular necrosis of the femoral head, with revision surgery rates exceeding 20% [ 7 ]. These issues are primarily attributed to inadequate preoperative fracture assessment and inappropriate surgical planning [ 8 – 9 ]. While patient age is a significant factor in preoperative evaluation, it is crucial to accurately assess the severity of the fracture, the stability of the fracture ends, and the blood supply to the femoral head, which relies on the classification of femoral neck fractures. The commonly used classification systems in clinical practice include anatomical location-based classification, the AO classification, the Garden classification, and the Pauwels classification [ 10 – 12 ]. Clinically, multiple classification systems are often used in conjunction for evaluation, with the Pauwels classification providing more accurate assessments of fracture stability and the shear forces at the fracture site, thereby playing a decisive role in the choice of internal fixation method [ 13 ]. The traditional Pauwels classification is based on measuring the Pauwels angle from X-ray images. However, due to the presence of shortening, impaction, and displacement at the fracture ends, the accuracy of angle measurements can be compromised, which subsequently affects fracture assessment. Consequently, some researchers have proposed modified methods for measuring the Pauwels angle, which, while addressing some shortcomings of the traditional approach, still carry a degree of error [ 14 ]. Three-dimensional (3D) CT reconstruction technology allows for multi-angle, multi-plane, and three-dimensional visualization of tissue structures and has been widely applied in clinical imaging examinations. Based on this, the present study aims to explore a more precise method for measuring the Pauwels angle in femoral neck fractures, with the goal of accurately assessing fracture conditions, guiding surgical planning, and reducing the rates of surgical failure and complications. Materials and Methods Patient Information: Patients with femoral neck fractures who visited the Shenyang Medical College Affiliated Central Hospital from January 2022 to January 2023 were selected. A total of 40 patients (male n=18, female n=22) were included, following strict inclusion and exclusion criteria. Inclusion and Exclusion Criteria: Inclusion Criteria: 1.Diagnosis of femoral neck fracture due to trauma; 2．Age between 18 and 75 years, with mature skeletal development, and patients and their families opting for surgical treatment. Exclusion Criteria: 1.Patients with open injuries or those requiring external fixation; 2.Pathological fractures; 3.Patients with traumatic brain injuries; 4.Patients with old fractures; 5.Patients whose imaging data do not meet the standards. Ethical Approval: This study was approved by the Medical Ethics Committee of the Shenyang Medical College Affiliated Central Hospital, and informed consent was obtained from the patients and their families. Data Collection The PACS Workstation system was used to strictly collect information on patients with femoral neck fractures, including bilateral anteroposterior X-rays of the hips and three-dimensional CT imaging of the affected hip, which were stored on a medical imaging platform. X-ray Examination Method All patients underwent X-ray imaging using a Philips digital radiography system. The positioning standard was as follows: the patient lay supine on the examination table, with both lower limbs in a neutral extended position and both feet internally rotated approximately 15°. Three-dimensional CT Reconstruction Examination Method Hip CT scans were performed using a Philips 256-slice spiral CT machine with the following scanning parameters: voltage of 120 kV, current of 125 mA, slice thickness of 1 mm, matrix size of 512 × 512, and DFOV of 500 mm. After scanning, CT data were reconstructed using a standard body thickness of 1.5 mm for thin-slice volume reconstruction. Measurement and Reading of Pauwels Angle Measurement of Pauwels Angle Using X-ray Method 1.Determination of the Long Axis of the Femoral Shaft: Identify the midpoint of the transverse diameter of the medullary cavity at the inferior edge of the lesser trochanter and the midpoint of the transverse diameter of the medullary cavity at the most distal end of the femoral shaft visible on the X-ray. Connect these two points to form line a, which represents the long axis of the femoral shaft. 2.Establishing the Baseline: Draw a perpendicular line through the upper edge of the femoral head that intersects line a, which serves as baseline b. 3.Determination of the Fracture Line: The fracture line c is defined as the line connecting the nearest points of the medial and lateral cortices of the distal end of the femoral neck fracture. 4.Pauwels Angle Measurement: The Pauwels angle (α) is the angle formed between the fracture line c and the baseline b. See Fig. 1 for details. Please place Fig. 1 here. Measurement of Pauwels Angle Using CT Imaging Method 1.The CT method also employs a modified measurement approach for the Pauwels angle. In this study, the central slice of the reconstructed coronal CT images of the femoral neck was selected as the measurement plane for the Pauwels angle. In the coronal CT images, the angle of the coronal plane was rotated to make the cutting plane parallel to the axis of the affected femoral neck. Then, the images were reconstructed layer by layer from front to back (with each reconstructed coronal slice spaced 1.5 mm apart), allowing the observer to select the central slice from the layers where the femoral neck is visible to where it disappears, as the measurement plane for the Pauwels angle. 2.On this image, the long axis of the femoral shaft is determined by connecting the midpoint of the transverse diameter of the medullary cavity at the inferior edge of the lesser trochanter and the midpoint of the transverse diameter of the medullary cavity at the most distal end of the femoral shaft. This line (line a) represents the long axis of the femoral shaft. 3.A perpendicular line through the upper edge of the femoral head that intersects line a serves as baseline b. 4.The fracture line (line c) is defined as the line connecting the nearest points of the medial and lateral cortices of the distal end of the fracture. 5.The Pauwels angle is the angle formed between the fracture line c and the baseline b. See Fig. 2 for details. Please place Fig.2 here. Method for Reading the Value of Pauwels Angle The measurement of the Pauwels angle on both X-ray and CT images was conducted using the angle measurement tool in the PACS Workstation software. After the long axis of the femoral shaft, baseline, and fracture line have been established on the image, the angle measurement function is activated. The procedure involves sequentially clicking on a point on the baseline, the intersection point between the baseline and the fracture line, and a point on the fracture line. This process automatically calculates the angle. See Fig. 3 for details. Please place Fig. 3 here. Data Analysis Based on the inclusion and exclusion criteria, the data for the 40 cases included in the study were anonymized and stored on the medical imaging platform. Measurements of the Pauwels angle on X-ray and reconstructed coronal CT images were conducted by one chief physician, one attending physician, and one resident physician using the PACS Workstation system. Three months later, these three physicians re-measured the X-ray and CT images of the 40 cases. The average values of the two measurement results were calculated, and the Pauwels classification was performed. The differences in the Pauwels angles and classifications obtained by the three physicians using the X-ray and CT methods were compared and analyzed to evaluate the consistency and repeatability of the two measurement methods among different observers and within the same observer. Statistical Methods Data analysis was performed using SPSS 25.0 statistical software. Measurement data were expressed as X±S. The differences in the Pauwels angles measured by the three observers using the X-ray and CT methods were analyzed using paired sample t-tests. Chi-square tests were employed to analyze the differences in Pauwels classifications obtained by the two methods. The intra-class correlation coefficient (ICC) was used to evaluate the consistency and repeatability of the results measured by the two methods among different observers and within the same observer. Results There were statistically significant differences in the measurements and classifications of the Pauwels angle between the X-ray method and the CT method among the chief physician, attending physician, and resident physician, as detailed in Tables 1-4. The CT method demonstrated significantly higher consistency between different observers and repeatability within the same observer for measuring the Pauwels angle compared to the X-ray method. Refer to Table 5 and 6 for details. Table 1: Comparison of Pauwels Classification Measured by X-ray and CT Method by Chief Physician Measurement Method Sample Size Type I Type II Type III P Value X-ray Method 40 5 24 11 CT Method 40 14 16 10 0.011 Table 2: Comparison of Pauwels Classification Measured by X-ray and CT Method by Attending Physician Measurement Method Sample Size Type I Type II Type III P Value X-ray Method 40 8 19 13 CT Method 40 15 17 8 0.005 Table 3: Comparison of Pauwels Classification Measured by X-ray and CT Method by Resident Physician Measurement Method Sample Size Type I Type II Type III P Value X-ray Method 40 3 12 25 CT Method 40 10 21 9 0.003 Table 4: Analysis of Differences in Measurements of Pauwels Angle between X-ray and CT Methods [X±S, n=40] Measurement Method X-ray Method CT Method t Value P Value 1 48.21±9.77 44.51±9.30 2.905 0.007 2 47.87±10.64 43.26±9.33 3.516 0.001 3 51.94±9.39 47.14±9.79 3.568 0.001 Table 5: Consistency Analysis of Measurement Results between Different Physicians Using X-ray and CT Methods Measurement Method ICC (X-ray Method) 95% CI ICC (CT Method) 95% CI First Measurement 1 and 2 0.712 0.497-0.851 0.935 0.875-0.967 1 and 3 0.882 0.776-0.939 0.966 0.934-0.983 2 and 3 0.578 0.303-0.765 0.960 0.922-0.980 Second Measurement 1 and 2 0.357 0.026-0.617 0.896 0.802-0.947 1 and 3 0.631 0.376-0.797 0.952 0.906-0.976 2 and 3 0.596 0.327-0.775 0.873 0.761-0.934 Note: 1, 2, 3 represent the Chief Physician, Attending Physician, and Resident Physician, respectively; ICC indicates the intraclass correlation coefficient; 95% CI represents the 95% confidence interval. Table 6: Repeatability Analysis of Two Measurements by Three Physicians Measurement Method ICC (X-ray Method) 95% CI ICC (CT Method) 95% CI 1 0.767 0.583-0.877 0.945 0.894-0.972 2 0.720 0.509-0.850 0.918 0.842-0.958 3 0.754 0.561-0.869 0.964 0.928-0.982 Note: 1, 2, 3 represent the Chief Physician, Attending Physician, and Resident Physician, respectively; ICC indicates the intraclass correlation coefficient; 95% CI represents the 95% confidence interval. Discussion The treatment options for femoral neck fractures can be divided into conservative and surgical approaches. Conservative treatment is suitable for patients with stable fractures or those without significant displacement, although 10% to 40% of these patients may experience secondary fractures. Therefore, some scholars recommend that surgical treatment be prioritized for patients with femoral neck fractures. For middle-aged and young patients, the preferred surgical treatment is internal fixation, which is primarily determined by the type of fracture. Currently, there are many classification systems for femoral neck fractures. The Garden classification assesses the degree of fracture displacement, while the AO classification evaluates the fracture location, and both classifications show high inter-observer consistency. The Pauwels classification assesses fracture stability; however, its accuracy in measuring the Pauwels angle is poor, making classification difficult. Its consistency and reliability are lower than the aforementioned two classifications, leading some scholars to advise against its clinical use. The main purpose of internal fixation surgery is to counteract the shear force and stress at the fracture site, which are correlated with the angle of the fracture line, specifically the Pauwels angle. Thus, we proposed this study to explore a more accurate method for measuring the Pauwels angle. In this study, we selected the most central layer of the femoral neck on the coronal plane for CT measurement because this layer is where the density of the trabecular bone is highest and also represents the central axis extending from the femoral head to the femoral neck. This allows for a more accurate reflection of fracture stability. By comparing the differences in Pauwels angle measurement and classification between X-ray and 3D CT, our results showed that 3D CT significantly outperformed X-ray in terms of measurement repeatability. Furthermore, the average Pauwels angle measured by CT was smaller than that measured by X-ray. This is likely because, during CT measurements, the point of cortical interruption on the medial side of the femoral neck is often higher; conversely, X-ray measurements are easily affected by the anatomical structures of the greater and lesser trochanters and overlapping fracture ends, making it difficult for the observer to accurately identify the point of interruption, resulting in an overestimation of the angle. Additionally, some femoral neck fractures are of the interlocked type, where the fracture ends are interlocked. On the coronal plane of CT, the observer can clearly see the femoral head interlocked with the distal femoral neck, allowing for accurate selection of the points of cortical interruption on both sides as the fracture line. However, on X-rays, due to the overlap of interlocked fracture ends, the observer cannot precisely identify the closest points of interruption on both sides of the distal cortex. If the points of interruption on the inner and outer cortices of the interlocked femoral head are incorrectly selected as the fracture line, the measured Pauwels angle will be greater than the result from CT measurement. This indicates that relying solely on X-rays for classifying femoral neck fractures in clinical practice may lead to misclassification of some fractures that are stable as unstable, subsequently resulting in unnecessary joint replacement treatments. This exposes patients to avoidable surgical risks and iatrogenic injuries. Therefore, to enhance the accuracy of classification and optimize treatment plans, it is crucial to integrate CT reconstruction into Pauwels angle measurement. This approach not only allows for a more precise assessment of fracture stability but also ensures that patients receive appropriate treatment, thereby preventing potential complications and unnecessary injuries resulting from misdiagnosis. This study also has certain limitations. The small sample size (only 40 cases) may introduce bias, and there is a lack of follow-up studies on postoperative outcomes. Future research should aim to expand the sample size and conduct long-term follow-ups to validate the clinical significance of these two measurement methods. Conclusion Compared to X-ray measurements, the use of 3D CT for measuring the Pauwels angle of femoral neck fractures is more accurate, provides more reliable guidance for fracture classification, and demonstrates higher clinical repeatability. It is recommended to use CT as a substitute for X-ray in the preoperative assessment of fracture stability in patients with femoral neck fractures. Declarations Ethics approval and consent to participate All procedures were in accordance with the ethical standards of institutional and/or national research councils. The study received approval from the Ethics Board of Central Hospital affiliated with Shenyang Medical College. Informed consent was obtained from the patients. Consent for publication The authors affirm that human research participants provided informed consent for publication of the images in Figure（1,2 and 3）. Availability of data and materials The datasets generated and/or analysed during the current study are not publicly available due to limitations of ethical approval involving the patient data and anonymity but are available from the corresponding author on reasonable request. Competing interests The authors declare that they have no conflicts of interest concerning this article. Funding This study was supported by Natural Science Foundation of Liaoning Province (2024-MS-222), Liaoning Provincial Department of Education Fund Project (JYTMS20231396) and the Science and Technology Plan Project of Shenyang City (Grant no. 22-321-32-13). Authors' contributions All authors contributed to the preparation, design, and successful execution of the study. They actively participated in the hospitalization, surgical procedures, and subsequent follow-up processes involving the relevant patients. Tianyu Zhang、Rongda Xu ,Siyu Duan, Ming Sun and Hairui Liang were responsible for material preparation, data collection, and analysis. The initial draft of the manuscript was composed by Ming Sun, Hairui Liang and Tong Bai, with Zhencun Cai providing comments on earlier versions of the manuscript. All authors have read and approved the final manuscript. Acknowledgements The authors wish to thank the participants for their dedicated contribution to the project. Clinical trial number: not applicable. References Zhan YZ. Clinical Traumatic Orthopedic Epidemiology [J]. Beijing: People's Medical Publishing House, 2009: 155-159. Chinese. Zhang YZ. Femoral fractures. In: Zhang YZ. Clinical Traumatic Fractures Epidemiology [M]. Beijing: People's Medical Publishing House, 2014: 177-179. Chinese. Stoffel K, Zderic I, Gras F, et al. 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Gaspar D, Crnkovic T, Durovic D, et al. AO group, AO subgroup, Garden and Pauwels classification systems of femoral neck fractures: are they reliable and reproducible? [J]. Med Glas (Zenica), 2012, 9(2): 243-247. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5339390","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":374155519,"identity":"a4f76359-04a0-4bec-a43b-867f4241d9b7","order_by":0,"name":"Ming Sun","email":"","orcid":"","institution":"Central Hospital Affiliated to Shenyang Medical College","correspondingAuthor":false,"prefix":"","firstName":"Ming","middleName":"","lastName":"Sun","suffix":""},{"id":374155521,"identity":"e5b28409-2bf3-4810-a556-a7021ec8bf98","order_by":1,"name":"Hairui Liang","email":"","orcid":"","institution":"Central Hospital Affiliated to Shenyang Medical 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population aging [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Currently, elderly patients typically undergo joint replacement surgery, while younger and middle-aged patients are more often treated with internal fixation. The most common internal fixation methods for femoral neck fractures include the dynamic hip screw system and cannulated screw fixation. Depending on the type of fracture, fixation options can include three screws in a triangular configuration, four screws, or an F-shaped fixation [\u003cspan additionalcitationids=\"CR4 CR5\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. However, patients with femoral neck fractures often face several postoperative complications, such as fixation failure, non-union, and avascular necrosis of the femoral head, with revision surgery rates exceeding 20% [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. These issues are primarily attributed to inadequate preoperative fracture assessment and inappropriate surgical planning [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWhile patient age is a significant factor in preoperative evaluation, it is crucial to accurately assess the severity of the fracture, the stability of the fracture ends, and the blood supply to the femoral head, which relies on the classification of femoral neck fractures. The commonly used classification systems in clinical practice include anatomical location-based classification, the AO classification, the Garden classification, and the Pauwels classification [\u003cspan additionalcitationids=\"CR11\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Clinically, multiple classification systems are often used in conjunction for evaluation, with the Pauwels classification providing more accurate assessments of fracture stability and the shear forces at the fracture site, thereby playing a decisive role in the choice of internal fixation method [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe traditional Pauwels classification is based on measuring the Pauwels angle from X-ray images. However, due to the presence of shortening, impaction, and displacement at the fracture ends, the accuracy of angle measurements can be compromised, which subsequently affects fracture assessment. Consequently, some researchers have proposed modified methods for measuring the Pauwels angle, which, while addressing some shortcomings of the traditional approach, still carry a degree of error [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Three-dimensional (3D) CT reconstruction technology allows for multi-angle, multi-plane, and three-dimensional visualization of tissue structures and has been widely applied in clinical imaging examinations. Based on this, the present study aims to explore a more precise method for measuring the Pauwels angle in femoral neck fractures, with the goal of accurately assessing fracture conditions, guiding surgical planning, and reducing the rates of surgical failure and complications.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003e\u003cstrong\u003ePatient Information:\u003c/strong\u003e\u003cbr\u003e\u0026nbsp;Patients with femoral neck fractures who visited the Shenyang Medical College Affiliated Central Hospital from January 2022 to January 2023 were selected. A total of 40 patients (male n=18, female n=22) were included, following strict inclusion and exclusion criteria.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInclusion and Exclusion Criteria:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInclusion Criteria:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e1.Diagnosis of femoral neck fracture due to trauma;\u003c/p\u003e\n\u003cp\u003e2．Age between 18 and 75 years, with mature skeletal development, and patients and their families opting for surgical treatment.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eExclusion Criteria:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e1.Patients with open injuries or those requiring external fixation;\u003c/p\u003e\n\u003cp\u003e2.Pathological fractures;\u003c/p\u003e\n\u003cp\u003e3.Patients with traumatic brain injuries;\u003c/p\u003e\n\u003cp\u003e4.Patients with old fractures;\u003c/p\u003e\n\u003cp\u003e5.Patients whose imaging data do not meet the standards.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical Approval:\u003c/strong\u003e\u003cbr\u003e\u0026nbsp;This study was approved by the Medical Ethics Committee of the Shenyang Medical College Affiliated Central Hospital, and informed consent was obtained from the patients and their families.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Collection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe PACS Workstation system was used to strictly collect information on patients with femoral neck fractures, including bilateral anteroposterior X-rays of the hips and three-dimensional CT imaging of the affected hip, which were stored on a medical imaging platform.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eX-ray Examination Method\u003c/strong\u003e\u003cbr\u003e\u0026nbsp;All patients underwent X-ray imaging using a Philips digital radiography system. The positioning standard was as follows: the patient lay supine on the examination table, with both lower limbs in a neutral extended position and both feet internally rotated approximately 15\u0026deg;.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eThree-dimensional CT Reconstruction Examination Method\u003c/strong\u003e\u003cbr\u003e\u0026nbsp;Hip CT scans were performed using a Philips 256-slice spiral CT machine with the following scanning parameters: voltage of 120 kV, current of 125 mA, slice thickness of 1 mm, matrix size of 512 \u0026times; 512, and DFOV of 500 mm. After scanning, CT data were reconstructed using a standard body thickness of 1.5 mm for thin-slice volume reconstruction.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMeasurement and Reading of Pauwels Angle\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMeasurement of Pauwels Angle Using X-ray Method\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e1.Determination of the Long Axis of the Femoral Shaft: Identify the midpoint of the transverse diameter of the medullary cavity at the inferior edge of the lesser trochanter and the midpoint of the transverse diameter of the medullary cavity at the most distal end of the femoral shaft visible on the X-ray. Connect these two points to form line a, which represents the long axis of the femoral shaft.\u003c/p\u003e\n\u003cp\u003e2.Establishing the Baseline: Draw a perpendicular line through the upper edge of the femoral head that intersects line a, which serves as baseline b.\u003c/p\u003e\n\u003cp\u003e3.Determination of the Fracture Line: The fracture line c is defined as the line connecting the nearest points of the medial and lateral cortices of the distal end of the femoral neck fracture.\u003c/p\u003e\n\u003cp\u003e4.Pauwels Angle Measurement: The Pauwels angle (\u0026alpha;) is the angle formed between the fracture line c and the baseline b. See\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eFig. 1\u003c/strong\u003e for details.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePlease place \u003cstrong\u003eFig. 1\u003c/strong\u003e here.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMeasurement of Pauwels Angle Using CT Imaging Method\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e1.The CT method also employs a modified measurement approach for the Pauwels angle. In this study, the central slice of the reconstructed coronal CT images of the femoral neck was selected as the measurement plane for the Pauwels angle. In the coronal CT images, the angle of the coronal plane was rotated to make the cutting plane parallel to the axis of the affected femoral neck. Then, the images were reconstructed layer by layer from front to back (with each reconstructed coronal slice spaced 1.5 mm apart), allowing the observer to select the central slice from the layers where the femoral neck is visible to where it disappears, as the measurement plane for the Pauwels angle.\u003c/p\u003e\n\u003cp\u003e2.On this image, the long axis of the femoral shaft is determined by connecting the midpoint of the transverse diameter of the medullary cavity at the inferior edge of the lesser trochanter and the midpoint of the transverse diameter of the medullary cavity at the most distal end of the femoral shaft. This line (line a) represents the long axis of the femoral shaft.\u003c/p\u003e\n\u003cp\u003e3.A perpendicular line through the upper edge of the femoral head that intersects line a serves as baseline b.\u003c/p\u003e\n\u003cp\u003e4.The fracture line (line c) is defined as the line connecting the nearest points of the medial and lateral cortices of the distal end of the fracture.\u003c/p\u003e\n\u003cp\u003e5.The Pauwels angle is the angle formed between the fracture line c and the baseline b. See\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eFig. 2\u003c/strong\u003e for details.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePlease place \u003cstrong\u003eFig.2\u0026nbsp;\u003c/strong\u003ehere.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethod for Reading the Value of Pauwels Angle\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe measurement of the Pauwels angle on both X-ray and CT images was conducted using the angle measurement tool in the PACS Workstation software. After the long axis of the femoral shaft, baseline, and fracture line have been established on the image, the angle measurement function is activated. The procedure involves sequentially clicking on a point on the baseline, the intersection point between the baseline and the fracture line, and a point on the fracture line. This process automatically calculates the angle. See\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eFig. 3\u003c/strong\u003e for details.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePlease place \u003cstrong\u003eFig. 3\u003c/strong\u003e here.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eBased on the inclusion and exclusion criteria, the data for the 40 cases included in the study were anonymized and stored on the medical imaging platform. Measurements of the Pauwels angle on X-ray and reconstructed coronal CT images were conducted by one chief physician, one attending physician, and one resident physician using the PACS Workstation system. Three months later, these three physicians re-measured the X-ray and CT images of the 40 cases. The average values of the two measurement results were calculated, and the Pauwels classification was performed. The differences in the Pauwels angles and classifications obtained by the three physicians using the X-ray and CT methods were compared and analyzed to evaluate the consistency and repeatability of the two measurement methods among different observers and within the same observer.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical Methods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData analysis was performed using SPSS 25.0 statistical software. Measurement data were expressed as X\u0026plusmn;S. The differences in the Pauwels angles measured by the three observers using the X-ray and CT methods were analyzed using paired sample t-tests. Chi-square tests were employed to analyze the differences in Pauwels classifications obtained by the two methods. The intra-class correlation coefficient (ICC) was used to evaluate the consistency and repeatability of the results measured by the two methods among different observers and within the same observer.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThere were statistically significant differences in the measurements and classifications of the Pauwels angle between the X-ray method and the CT method among the chief physician, attending physician, and resident physician, as detailed in Tables 1-4.\u003c/p\u003e\n\u003cp\u003eThe CT method demonstrated significantly higher consistency between different observers and repeatability within the same observer for measuring the Pauwels angle compared to the X-ray method. Refer to Table 5 and 6 for details.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1: Comparison of Pauwels Classification Measured by X-ray and CT Method by Chief Physician\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.4086%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMeasurement Method\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.3548%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSample Size\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9.67742%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eType I\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eType II\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9032%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eType III\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.8375%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.4086%;\"\u003e\n \u003cp\u003eX-ray Method\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.3548%;\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9.67742%;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9032%;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.8375%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.4086%;\"\u003e\n \u003cp\u003eCT Method\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.3548%;\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9.67742%;\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9032%;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.8375%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.4086%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 19.3548%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 9.67742%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 12.9032%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 11.8375%;\"\u003e\n \u003cp\u003e0.011\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2: Comparison of Pauwels Classification Measured by X-ray and CT Method by Attending Physician\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.4086%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMeasurement Method\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.3548%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSample Size\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9.67742%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eType I\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eType II\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9032%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eType III\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.4086%;\"\u003e\n \u003cp\u003eX-ray Method\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.3548%;\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9.67742%;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9032%;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.4086%;\"\u003e\n \u003cp\u003eCT Method\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.3548%;\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9.67742%;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9032%;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.4086%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 19.3548%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 9.67742%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 12.9032%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e0.005\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3: Comparison of Pauwels Classification Measured by X-ray and CT Method by Resident Physician\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.4086%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMeasurement Method\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.3548%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSample Size\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9.67742%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eType I\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eType II\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9032%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eType III\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.4086%;\"\u003e\n \u003cp\u003eX-ray Method\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.3548%;\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9.67742%;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9032%;\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.4086%;\"\u003e\n \u003cp\u003eCT Method\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19.3548%;\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 9.67742%;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12.9032%;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.4086%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 19.3548%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 9.67742%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 12.9032%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 11.828%;\"\u003e\n \u003cp\u003e0.003\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4: Analysis of Differences in Measurements of Pauwels Angle between X-ray and CT Methods [X\u0026plusmn;S, n=40]\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 33%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMeasurement Method\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eX-ray Method\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCT Method\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11%;\"\u003e\n \u003cp\u003e\u003cstrong\u003et Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP Value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.7368%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.1579%;\"\u003e\n \u003cp\u003e48.21\u0026plusmn;9.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.9474%;\"\u003e\n \u003cp\u003e44.51\u0026plusmn;9.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.5789%;\"\u003e\n \u003cp\u003e2.905\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.5789%;\"\u003e\n \u003cp\u003e0.007\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.7368%;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.1579%;\"\u003e\n \u003cp\u003e47.87\u0026plusmn;10.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.9474%;\"\u003e\n \u003cp\u003e43.26\u0026plusmn;9.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.5789%;\"\u003e\n \u003cp\u003e3.516\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.5789%;\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 34.7368%;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23.1579%;\"\u003e\n \u003cp\u003e51.94\u0026plusmn;9.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 18.9474%;\"\u003e\n \u003cp\u003e47.14\u0026plusmn;9.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.5789%;\"\u003e\n \u003cp\u003e3.568\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11.5789%;\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 5: Consistency Analysis of Measurement Results between Different Physicians Using X-ray and CT Methods\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 25%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMeasurement Method\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 24%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eICC (X-ray Method)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95% CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eICC (CT Method)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95% CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26.0417%;\"\u003e\n \u003cp\u003eFirst Measurement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 21.875%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26.0417%;\"\u003e\n \u003cp\u003e1 and 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25%;\"\u003e\n \u003cp\u003e0.712\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.497-0.851\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.875%;\"\u003e\n \u003cp\u003e0.935\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.875-0.967\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26.0417%;\"\u003e\n \u003cp\u003e1 and 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25%;\"\u003e\n \u003cp\u003e0.882\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.776-0.939\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.875%;\"\u003e\n \u003cp\u003e0.966\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.934-0.983\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26.0417%;\"\u003e\n \u003cp\u003e2 and 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25%;\"\u003e\n \u003cp\u003e0.578\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.303-0.765\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.875%;\"\u003e\n \u003cp\u003e0.960\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.922-0.980\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26.0417%;\"\u003e\n \u003cp\u003eSecond Measurement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 21.875%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26.0417%;\"\u003e\n \u003cp\u003e1 and 2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25%;\"\u003e\n \u003cp\u003e0.357\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.026-0.617\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.875%;\"\u003e\n \u003cp\u003e0.896\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.802-0.947\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26.0417%;\"\u003e\n \u003cp\u003e1 and 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25%;\"\u003e\n \u003cp\u003e0.631\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.376-0.797\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.875%;\"\u003e\n \u003cp\u003e0.952\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.906-0.976\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26.0417%;\"\u003e\n \u003cp\u003e2 and 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25%;\"\u003e\n \u003cp\u003e0.596\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.327-0.775\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.875%;\"\u003e\n \u003cp\u003e0.873\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.761-0.934\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eNote:\u003c/strong\u003e 1, 2, 3 represent the Chief Physician, Attending Physician, and Resident Physician, respectively; ICC indicates the intraclass correlation coefficient; 95% CI represents the 95% confidence interval.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 6: Repeatability Analysis of Two Measurements by Three Physicians\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26.0417%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMeasurement Method\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eICC (X-ray Method)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95% CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.875%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eICC (CT Method)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95% CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26.0417%;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25%;\"\u003e\n \u003cp\u003e0.767\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.583-0.877\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.875%;\"\u003e\n \u003cp\u003e0.945\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.894-0.972\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26.0417%;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25%;\"\u003e\n \u003cp\u003e0.720\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.509-0.850\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.875%;\"\u003e\n \u003cp\u003e0.918\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.842-0.958\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26.0417%;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25%;\"\u003e\n \u003cp\u003e0.754\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.561-0.869\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.875%;\"\u003e\n \u003cp\u003e0.964\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13.5417%;\"\u003e\n \u003cp\u003e0.928-0.982\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eNote:\u003c/strong\u003e 1, 2, 3 represent the Chief Physician, Attending Physician, and Resident Physician, respectively; ICC indicates the intraclass correlation coefficient; 95% CI represents the 95% confidence interval.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe treatment options for femoral neck fractures can be divided into conservative and surgical approaches. Conservative treatment is suitable for patients with stable fractures or those without significant displacement, although 10% to 40% of these patients may experience secondary fractures. Therefore, some scholars recommend that surgical treatment be prioritized for patients with femoral neck fractures. For middle-aged and young patients, the preferred surgical treatment is internal fixation, which is primarily determined by the type of fracture. Currently, there are many classification systems for femoral neck fractures. The Garden classification assesses the degree of fracture displacement, while the AO classification evaluates the fracture location, and both classifications show high inter-observer consistency. The Pauwels classification assesses fracture stability; however, its accuracy in measuring the Pauwels angle is poor, making classification difficult. Its consistency and reliability are lower than the aforementioned two classifications, leading some scholars to advise against its clinical use. The main purpose of internal fixation surgery is to counteract the shear force and stress at the fracture site, which are correlated with the angle of the fracture line, specifically the Pauwels angle. Thus, we proposed this study to explore a more accurate method for measuring the Pauwels angle.\u003c/p\u003e\n\u003cp\u003eIn this study, we selected the most central layer of the femoral neck on the coronal plane for CT measurement because this layer is where the density of the trabecular bone is highest and also represents the central axis extending from the femoral head to the femoral neck. This allows for a more accurate reflection of fracture stability. By comparing the differences in Pauwels angle measurement and classification between X-ray and 3D CT, our results showed that 3D CT significantly outperformed X-ray in terms of measurement repeatability. Furthermore, the average Pauwels angle measured by CT was smaller than that measured by X-ray. This is likely because, during CT measurements, the point of cortical interruption on the medial side of the femoral neck is often higher; conversely, X-ray measurements are easily affected by the anatomical structures of the greater and lesser trochanters and overlapping fracture ends, making it difficult for the observer to accurately identify the point of interruption, resulting in an overestimation of the angle.\u003c/p\u003e\n\u003cp\u003eAdditionally, some femoral neck fractures are of the interlocked type, where the fracture ends are interlocked. On the coronal plane of CT, the observer can clearly see the femoral head interlocked with the distal femoral neck, allowing for accurate selection of the points of cortical interruption on both sides as the fracture line. However, on X-rays, due to the overlap of interlocked fracture ends, the observer cannot precisely identify the closest points of interruption on both sides of the distal cortex. If the points of interruption on the inner and outer cortices of the interlocked femoral head are incorrectly selected as the fracture line, the measured Pauwels angle will be greater than the result from CT measurement.\u003c/p\u003e\n\u003cp\u003eThis indicates that relying solely on X-rays for classifying femoral neck fractures in clinical practice may lead to misclassification of some fractures that are stable as unstable, subsequently resulting in unnecessary joint replacement treatments. This exposes patients to avoidable surgical risks and iatrogenic injuries. Therefore, to enhance the accuracy of classification and optimize treatment plans, it is crucial to integrate CT reconstruction into Pauwels angle measurement. This approach not only allows for a more precise assessment of fracture stability but also ensures that patients receive appropriate treatment, thereby preventing potential complications and unnecessary injuries resulting from misdiagnosis.\u003c/p\u003e\n\u003cp\u003eThis study also has certain limitations. The small sample size (only 40 cases) may introduce bias, and there is a lack of follow-up studies on postoperative outcomes. Future research should aim to expand the sample size and conduct long-term follow-ups to validate the clinical significance of these two measurement methods.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eCompared to X-ray measurements, the use of 3D CT for measuring the Pauwels angle of femoral neck fractures is more accurate, provides more reliable guidance for fracture classification, and demonstrates higher clinical repeatability. It is recommended to use CT as a substitute for X-ray in the preoperative assessment of fracture stability in patients with femoral neck fractures.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll procedures were in accordance with the ethical standards of institutional and/or national research councils. The study received approval from the Ethics Board of Central Hospital affiliated with Shenyang Medical College. Informed consent was obtained from the patients.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors affirm that human research participants provided informed consent for publication of the images in Figure（1,2 and 3）.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets generated and/or analysed during the current study are not publicly available due to limitations of ethical approval involving the patient data and anonymity but are available from the corresponding author on reasonable request.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no conflicts of interest concerning this article.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was supported by Natural Science Foundation of Liaoning Province (2024-MS-222), Liaoning Provincial Department of Education Fund Project (JYTMS20231396) and the Science and Technology Plan Project of Shenyang City (Grant no. 22-321-32-13).\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;All authors contributed to the preparation, design, and successful execution of the study. They actively participated in the hospitalization, surgical procedures, and subsequent follow-up processes involving the relevant patients. Tianyu Zhang、Rongda Xu ,Siyu Duan, Ming Sun and Hairui Liang were responsible for material preparation, data collection, and analysis. The initial draft of the manuscript was composed by Ming Sun, Hairui Liang and Tong Bai, with Zhencun Cai providing comments on earlier versions of the manuscript. All authors have read and approved the final manuscript. \u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe authors wish to thank the participants for their dedicated contribution to the project.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number: not applicable.\u003c/strong\u003e\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eZhan YZ. Clinical Traumatic Orthopedic Epidemiology [J]. Beijing: People\u0026apos;s Medical Publishing House, 2009: 155-159. Chinese. \u003c/li\u003e\n\u003cli\u003eZhang YZ. Femoral fractures. In: Zhang YZ. Clinical Traumatic Fractures Epidemiology [M]. Beijing: People\u0026apos;s Medical Publishing House, 2014: 177-179. Chinese. \u003c/li\u003e\n\u003cli\u003eStoffel K, Zderic I, Gras F, et al. Biomechanical evaluation of the femoral neck system in unstable Pauwels III femoral neck fractures: a comparison with the dynamic hip screw and cannulated screws [J]. J Orthop Trauma, 2017, 31(3): 131-137. \u003c/li\u003e\n\u003cli\u003eSiavashi B, Aalirezaei A, Moosavi M, et al. A comparative study between multiple cannulated screws and dynamic hip screw for fixation of femoral neck fracture in adults [J]. Int Orthop, 2015, 39(10): 2069-2071. \u003c/li\u003e\n\u003cli\u003eRajnish RK, Haq RU, Aggarwal AN, et al. Four screws diamond configuration fixation for displaced, comminuted intracapsular fracture neck femur in young adults [J]. Indian J Orthop, 2019, 53(1): 70-76. \u003c/li\u003e\n\u003cli\u003eSAMI A, PRABHAKAR R, KUMAR YADAV A, et al. Bi-planed double supported screw fixation for femoral neck fracture in young adults: a prospective cohort study [J]. J Orthop, 2022, 33: 117-123. \u003c/li\u003e\n\u003cli\u003eSlobogean GP, Sprague SA, Scott T, Bhandari M. Complications following young femoral neck fractures [J]. Injury, 2015, 46(3): 484-491. doi: 10.1016/j.injury.2014.10.010. Epub 2014 Oct 31. \u003c/li\u003e\n\u003cli\u003eLi J, Yin P, Zhang L, et al. Medial anatomical buttress plate in treating displaced femoral neck fracture: a finite element analysis [J]. Injury, 2019, 50(11): 1895-1900. \u003c/li\u003e\n\u003cli\u003eLin T, Yang P, Xu J, et al. Finite element analysis of different internal fixation methods for the treatment of Pauwels type III femoral neck fracture [J]. Biomedicine \u0026amp; Pharmacotherapy, 2019, 112: 108658. \u003c/li\u003e\n\u003cli\u003eGarden RS. Low-angle fixation in fractures of the femoral neck [J]. J Bone Joint Surg Br, 1961, 4(43): 647-663. \u003c/li\u003e\n\u003cli\u003eFlorschutz AV, Langford JR, Haidukewych GJ, et al. Femoral neck fractures: current management [J]. J Orthop Trauma, 2015, 29(3): 121-129. \u003c/li\u003e\n\u003cli\u003eTurgut A, Kumbacaraci M, Kalendere O, et al. Is surgeon\u0026apos;s experience important on intra- and inter-observer reliability of classification used for adult femoral neck fracture? [J]. Acta Orthop Traumatol Turc, 2016, 50(6): 601-605. \u003c/li\u003e\n\u003cli\u003evan Embden D, Roukema GR, Rhemrev SJ, et al. The Pauwels classification for intracapsular hip fractures: is it reliable? [J]. Injury, 2011, 42(11): 1238-1240. \u003c/li\u003e\n\u003cli\u003eWang SH, Yang JJ, Shen HC, et al. Using a modified Pauwels method to predict the outcome of femoral neck fracture in relatively young patients [J]. Injury, 2015, 46(10): 1969-1974. \u003c/li\u003e\n\u003cli\u003eHelbig L, Werner M, Schneider S, et al. Garden I femoral neck fractures: conservative vs operative therapy [J]. Orthopade, 2005, 34(10): 1040-1045. \u003c/li\u003e\n\u003cli\u003eCserh\u0026aacute;ti P, Kazar G, Manninger J, et al. Non-operative or operative treatment for undisplaced femoral neck fractures: a comparative study of 122 non-operatively and 125 operatively treated cases [J]. Injury, 1996, 27(8): 583-588. \u003c/li\u003e\n\u003cli\u003eConn KS, Parker MJ. Undisplaced intracapsular hip fractures: results of internal fixation in 375 patients [J]. Clin Orthop Relat Res, 2004, 421: 249-254. \u003c/li\u003e\n\u003cli\u003eTurgut A, Kumbacaraci M, Kalendere O, et al. Is surgeon\u0026apos;s experience important on intra- and inter-observer reliability of classifications used for adult femoral neck fracture? [J]. Acta Orthop Traumatol Turc, 2016, 50(6): 601-605. \u003c/li\u003e\n\u003cli\u003eGaspar D, Crnkovic T, Durovic D, et al. AO group, AO subgroup, Garden and Pauwels classification systems of femoral neck fractures: are they reliable and reproducible? [J]. Med Glas (Zenica), 2012, 9(2): 243-247. \u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"X-ray, 3D CT scan, femoral neck fracture, Pauwels classification","lastPublishedDoi":"10.21203/rs.3.rs-5339390/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5339390/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eTo compare the accuracy of X-ray and 3D CT in measuring the Pauwels angle of femoral neck fractures and the reliability of these methods in guiding Pauwels classification.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eX-ray and CT images of 40 femoral neck fracture patients from our hospital were collected. Three physicians measured the Pauwels angle on both X-ray and CT images using the PACS Workstation system, performing the measurements twice and classifying the fractures based on the Pauwels classification. Consistency and reproducibility analyses were conducted to evaluate the performance of the two methods.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe Pauwels angles and classification results obtained by the chief physician, attending physician, and resident physician using both X-ray and CT methods showed statistically significant differences, with P values all \u0026lt;\u0026thinsp;0.05. For the consistency analysis, the interclass correlation coefficients (ICC) for two measurements were: for the X-ray method, ICCs of 0.712, 0.882, and 0.578 for 1vs2, 1vs3, and 2vs3, respectively, and ICCs of 0.357, 0.631, and 0.596 for the same pairs; for the CT method, ICCs of 0.935, 0.966, and 0.960 for 1vs2, 1vs3, and 2vs3, and ICCs of 0.896, 0.952, and 0.872 for the same pairs. The reproducibility analysis for the three physicians showed that the ICCs for the X-ray method were 0.767, 0.720, and 0.754, while for the CT method, the ICCs were 0.945, 0.918, and 0.964. The CT method demonstrated superior consistency and reproducibility compared to the X-ray method.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eCompared to X-rays, 3D CT scanning is more accurate in measuring the Pauwels angle of femoral neck fractures and provides more reliable guidance for Pauwels classification, with higher clinical reproducibility. Therefore, it is recommended to use CT scanning instead of X-ray for preoperative evaluation of fracture stability in femoral neck fracture patients.\u003c/p\u003e","manuscriptTitle":"A Comparative Study of X-ray and 3D CT in the Evaluation of Pauwels Classification for Femoral Neck Fractures","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-11-20 11:16:07","doi":"10.21203/rs.3.rs-5339390/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"42692340-6562-44b4-8138-17ccebff2b5e","owner":[],"postedDate":"November 20th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-12-18T05:39:06+00:00","versionOfRecord":[],"versionCreatedAt":"2024-11-20 11:16:07","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5339390","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5339390","identity":"rs-5339390","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}