Preoperative Evaluation for Posterior Labral Tears in Anterior Shoulder Instability: Diagnostic Efficacy of MRI

Preoperative Evaluation for Posterior Labral Tears in Anterior Shoulder Instability: Diagnostic Efficacy of MRI | 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 Preoperative Evaluation for Posterior Labral Tears in Anterior Shoulder Instability: Diagnostic Efficacy of MRI Amir Bisadi, Mehdi Rahimi, Fatemeh Abbasi, Mohammad H Mahrooz, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7584450/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 Purpose Shoulder arthroscopy remains the gold standard for diagnosing shoulder instability. While magnetic resonance imaging (MRI) demonstrates consistent accuracy in detecting anterior labral injuries associated with glenohumeral instability, discrepancies persist between radiologists and orthopedic surgeons regarding the interpretation of MRI findings for posterior labral tears. This study aims to evaluate the diagnostic efficacy of preoperative MRI in identifying posterior labral tears in patients with anterior shoulder instability undergoing arthroscopic Bankart repair. Methods A retrospective study was conducted between December 2016 and December 2023, involving 265 patients with traumatic anterior glenohumeral instability who were candidates for Bankart lesion repair. The diagnostic performance of MRI in detecting posterior labral lesions was assessed against shoulder arthroscopy, considered the gold standard. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated based on MRI findings interpreted by a radiologist and two orthopedic surgeons independently. Results The mean age of the patients was 29.1 years. The sensitivity of preoperative MRI for diagnosing posterior labral tears was 46.8% for the radiologist and 44.0% and 43.1% for the two orthopedic surgeons. Specificity was 86.5% for the radiologist and 91.0% for both surgeons. The PPV values were 70.8% (radiologist), 77.4% (surgeon 1), and 77.0% (surgeon 2), while the NPV values were 69.9%, 70.0%, and 69.6%, respectively. The overall accuracy of MRI in diagnosing posterior labral tears was reported as 70.2% (radiologist), 71.7% (surgeon 1), and 71.3% (surgeon 2). Conclusions MRI has limited accuracy in diagnosing posterior labral lesions, with shoulder arthroscopy remaining the gold standard. MRI and arthroscopy should be viewed as complementary tools in the evaluation of shoulder instability. Posterior labral tear Shoulder arthroscopy sensitivity specificity Figures Figure 1 Figure 2 Figure 3 INTRODUCTION The glenohumeral joint is the most commonly dislocated joint in the human body, accounting for approximately 50% of all joint dislocations and subluxations ( 1 ). In the United States, an average of 25.2 per 100,000 individuals experience shoulder dislocations annually, with the highest prevalence among young men aged 14–19 and those involved in military activities or throwing sports ( 2 – 4 ). Shoulder instability is classified by its cause, direction, onset, and degree, with unidirectional instability defined as either anterior or posterior. Approximately 95% of cases involve anterior or anterior-inferior instability, while posterior instability is less common, representing about 10% of cases ( 5 – 7 ). Shoulder instability often leads to dysfunction of the capsule, labrum, glenohumeral ligaments, rotator cuff, and surrounding muscles, potentially causing damage to the humeral head or glenoid process ( 8 ). Anterior instability is commonly associated with anterior-inferior labrum tears (Bankart lesions) ( 9 ). Posterior labrum tears, though less frequently recognized, may also occur with anterior instability ( 10 ). Burkhardt et al. hypothesized that 360-degree labral injuries, affecting the anterior labrum, could also involve the posterior labrum ( 11 ). Recent studies suggest that increased pressure on the posterior labrum following anterior dislocation might contribute to unrecognized injuries during Bankart repair ( 12 , 13 ). Timely identification and treatment of labral injuries are critical for successful management of shoulder instability, requiring thorough clinical and diagnostic evaluation. Advances in imaging techniques, such as computed tomography and magnetic resonance imaging (MRI), along with arthroscopic surgical methods, have improved diagnostic accuracy and treatment outcomes ( 14 ). Surgical intervention is often recommended for patients with a high risk of recurrent instability. Depending on the presence of labral tears or glenoid bone defects, procedures like open or arthroscopic Bankart repair may be required ( 15 ). While arthroscopy is the gold standard for diagnosing shoulder injuries due to its ability to directly visualize intra-articular structures with high magnification, it carries risks such as infection, damage to adjacent structures, and anesthetic complications ( 16 , 17 ). MRI is a non-ionizing, non-contrast imaging modality with high sensitivity for detecting soft tissue injuries, particularly anterior labral tears ( 18 ). However, controversy exists between radiologists and shoulder surgeons regarding the interpretation of MRI findings for posterior labral injuries. This study aims to evaluate the diagnostic accuracy of MRI compared to arthroscopy for detecting posterior labral tears in patients with anterior shoulder instability undergoing arthroscopic Bankart repair. METHODS This retrospective cohort study was conducted after receiving ethical approval from the Medical Sciences Ethics Committee [REC.1403.227]. The study included 300 patients with traumatic anterior shoulder instability who underwent arthroscopic Bankart repair between December 2016 and December 2023. Inclusion and Exclusion Criteria Patients were excluded if they had cardiac dysfunction, brachial plexus issues, systemic diseases (e.g., rheumatoid arthritis, lupus erythematosus), connective tissue disorders, age > 50 or < 16 years, unavailable or low-quality MRI scans, a history of prior glenohumeral surgery, or atraumatic/multidirectional instability. Of the 300 patients initially considered, 265 met the eligibility criteria. All patients underwent a clinical examination performed by senior orthopedists and preoperative MRI (Siemens 1.5-T MRI machine, T2-weighted axial sequences) as part of their evaluation. Surgical Procedure and Arthroscopic Evaluation After suprascapular regional block anesthesia, all patients underwent shoulder arthroscopy in the beach-chair position performed by a senior orthopedist using four standard portals (posterior, anterior, anterolateral, and lateral). In addition to addressing anterior instability, the posterior glenoid labrum was systematically evaluated for tears during arthroscopy (Fig. 1 ). MRI Interpretation MRI scans were reviewed independently by two fellowship-trained orthopedic surgeons and one musculoskeletal (MSK) radiologist specializing in sports medicine. The axial T2-weighted images were used to identify posterior labral tears (Fig. 2 ). A tear was defined as any injury posterior to a vertical line connecting the 12 o’clock and 6 o’clock positions on the glenoid labrum (Fig. 3 ). Discrepancies in diagnoses were resolved by majority opinion. MRI findings were classified as either positive or negative. Data Collection Demographic and clinical data, including age, gender, side involved, number and episodes of dislocation, duration of symptoms, socioeconomic status, and cause of trauma, were extracted from electronic medical records. Diagnoses of posterior labral tears were recorded separately and blindly for MRI and arthroscopy findings. Statistical Analysis Data were analyzed using SPSS version 26. Descriptive statistics (mean, standard deviation, frequency, and percentage) were used to summarize patient characteristics. Comparative analyses were performed using Fisher’s exact test and paired t-tests, as appropriate. Diagnostic performance metrics, including sensitivity (TP/(TP + FN)), specificity (TN/(FP + TN)), positive predictive value (PPV: TP/(TP + FP)), negative predictive value (NPV: TN/(FN + TN)), and overall accuracy ((TP + TN)/Total), were calculated. RESULTS A total of 265 patients were included in the study. Table 1 depicts the demographic information of the patients. Table 1 demographic data of patient with anterior shoulder instability (n = 265) Variable value Sex (%) Male 210 female 55 Age (mean-SD) 29.1 ± 6.38 Side involved (%) Left 116 Right 149 Number of dislocations >3 times 143 =<3 times 122 Duration of symptoms 13.38 ± 5.89 Social economic Good 135 poor 130 Couse of trouma Accident 87 Sport 127 Falling down 51 Each patient underwent MRI evaluation for the detection of posterior labral tears, interpreted independently by two orthopedic surgeons and one radiologist. The findings were compared with the arthroscopy results, which served as the gold standard. Table 2 demonstrates the comparison. The diagnostic performance of MRI for detecting labral tears was evaluated in terms of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). The results are summarized in Table 3 . The interclass correlation coefficient (ICC) was calculated to assess the agreement among the three specialists. The ICC was 0.847, indicating good reliability. The 95% confidence interval was 0.812 to 0.876 (p < 0.001), suggesting a high degree of consistency in the MRI interpretations for posterior labral tears across the radiologist and orthopedic surgeons. Table 2 comparison of MRI finding (Orthopedic Surgeon MRI Reading and Radiologic Report) with arthroscopy results Positive for labral tear Negative for labral tear MRI report by the orthopedic surgeon 1 62 203 MRI report by the orthopedic surgeon 2 61 204 MRI report by the radiologist 72 193 MRI report by the cohort 65 200 Arthroscopy (gold standard) 109 156 Table 3 sensitivity, specificity, PPV, NPV and accuracy of the MRI readings sensitivity specificity PPV NPV accuracy Radiologist 46.8% 86.5% 70.8% 69.9% 70.2% Orthopedic surgeon 1 44.0% 91.0% 77.4% 70.0% 71.7% Orthopedic surgeon 2 43.1% 91.0% 77.0% 69.6% 71.3% Cohort 56.9% 98.1% 95.4% 76.5% 81.1% DISCUSSION Shoulder labrum tears and instability are common presentations in emergency departments. Before the introduction of MRI, invasive diagnostic methods such as arthrography, double contrast arthrography-computed tomography, and arthroscopy were the primary tools for evaluating intra-articular pathologies associated with these conditions. MRI, a non-invasive method, has become the preferred choice for the clinical diagnosis of shoulder injuries due to its superior soft tissue contrast, high spatial resolution, and ability to provide multi-parametric evaluation of morphological changes in the injured shoulder joint. Since the 1980s, MRI has been utilized to diagnose shoulder pathologies, but its diagnostic accuracy for shoulder instability lesions remains limited. However, advancements in imaging technology have led to significant improvements in preoperative diagnosis ( 19 , 20 ). The unique anatomy of the shoulder joint makes it difficult to visualize posterior labrum tears in the true sagittal plane through MRI, contributing to the uncertainty regarding MRI's diagnostic accuracy for shoulder instability. High-quality evidence-based research is needed to improve our understanding of shoulder injury diagnosis. In our study, MRI showed low sensitivity (22.2%) but high specificity (100%) for diagnosing posterior shoulder labrum tears. These findings contrast with those of Sheridan et al., who reported a sensitivity of 66% and specificity of 77% for diagnosing superior labrum anterior-posterior (SLAP) lesions ( 23 , 24 ). Kumar et al. ( 22 ) also found that MRI had 100% sensitivity for rotator cuff and Bankart tears but only 60% sensitivity for diagnosing labral lesions, highlighting the limited accuracy for posterior labrum injuries. Arthroscopy remains the gold standard for diagnosing shoulder lesions, but MRI and arthroscopy complement each other in diagnosing shoulder instability ( 20 ). In line with our study, Meg et al. reported 89% sensitivity and 100% specificity for MRI in diagnosing anterior labrum tears ( 21 ). While some studies report higher sensitivity than our findings, Golan et al. ( 10 ) demonstrated that posterior extension of Bankart lesions in anterior shoulder dislocation occurs in approximately 18.5% of cases, emphasizing the importance of evaluating the posterior labrum on MRI arthrograms. The variability in findings across studies may stem from differences in imaging systems, MRI interpretation methods, and study design. Despite these discrepancies, most sources agree that clinical and imaging findings should be integrated for an accurate diagnosis. Our study also found that MRI had a positive predictive value (PPV) of 100% and a negative predictive value (NPV) of 52.3% for diagnosing posterior labrum tears. In contrast, Sheridan et al. ( 23 ) reported a PPV of 24% and an NPV of 95%, reflecting the inconsistencies in MRI’s diagnostic capabilities. Baptista et al. ( 24 ) found PPVs between 86% and 88% for various shoulder tears, suggesting that MRI alone may miss some cases, making clinical correlation essential for surgical decision-making. The differences in study results may be attributed to factors such as the degree and location of tears, the MRI cut used, and the skill of the MRI interpreter. More research is needed to better define these variables. Our analysis showed that MRI had a diagnostic accuracy of 58% for diagnosing posterior labrum tears, which is consistent with other studies that report moderate accuracy for upper labrum tears (76%) ( 24 ) and partial to complete tendon ruptures (57–92%) ( 25 ). A meta-analysis comparing arthrography with MRI found that arthrography had higher diagnostic accuracy for labral lesions ( 26 ). Despite the lower diagnostic accuracy in our study, it’s important to note that the anatomical positioning of the posterior labrum contributes to the difficulty in detecting tears via MRI. Additionally, differences in MRI equipment, interpreter experience, and injury type could explain the discrepancies in study outcomes. Limitations of the Study: This study’s sample size was limited due to time and financial constraints, which may affect the generalizability of the results. Future studies with larger sample sizes are recommended. Additionally, the cross-sectional design of the study restricts causal inference, and the use of convenience sampling may limit generalizability. Longitudinal studies with larger, more diverse patient populations could provide more accurate, generalizable findings. CONCLUSION The findings of this study suggest that MRI alone should not be relied upon for diagnosing posterior labrum tears in patients with anterior shoulder instability, as its sensitivity and specificity for detecting these injuries are limited. Failure to address posterior labrum tears during surgery for anterior labrum tears may contribute to treatment failure. Therefore, it is crucial that shoulder arthroscopy not only evaluates the anterior labrum but also includes a thorough examination of the posterior labrum, with surgeons being prepared to repair any posterior labral tears identified during the procedure. Abbreviations MRI Magnetic Resonance Imaging PPV Positive Predictive Value NPV Negative Predictive Value ICC Intraclass Correlation Coefficient Declarations Ethics approval and consent to participate This retrospective cohort study was conducted after receiving ethical approval from the Shahid Beheshti University of Medical Sciences Ethics Committee [IR.SBMU.MSP.REC.1403.227]. We confirm that all methods were performed in accordance with the Declaration of Helsinki and relevant institutional guidelines and regulations. Due to the retrospective nature of the study, the need for obtaining informed consent was waived by the Shahid Beheshti University of Medical Sciences Institutional Review Board (IRB). Consent for publication Not applicable. Availability of data and materials: The datasets generated and/or analysed during the current study are not publicly available but are available from the corresponding author on reasonable request. Competing Interests: The authors declare that they have no competing interests. Funding: This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Authors' contributions: Amir Bisadi: Data collection, manuscript drafting. Mehdi Rahimi: Statistical analysis, data interpretation. Fatemeh Abbasi: Literature review, manuscript drafting and editing. Mohammad H. Mahrooz: Data collection, critical revision. Morteza Gholipour: Study conception, surgical procedures, supervision, and corresponding author. All authors read and approved the final manuscript. Acknowledgements: The authors would like to thank the staff of Akhtar Orthopedic Hospital for their assistance in data collection and patient management. Data availability: available The datasets generated and/or analysed during the current study are not publicly available but are available from the corresponding author on reasonable request. References Zandi S, Rajabi R, Minoonejad H, Mohseni-Bandpei M. Upper quarter functional stability in female volleyball players with and without anterior shoulder instability, with consideration of arm dominance. Archives Rehabilitation. 2016;16(4):346–55. Becker B, Spadafore S, Oberle L, Spittler J, Khodaee M. Epidemiology of shoulder dislocation treated at emergency departments in the United States Between 1997 and 2021. Orthop J sports Med. 2024;12(3):23259671241234930. Longo UG, Salvatore G, Locher J, Ruzzini L, Candela V, Berton A, et al. Epidemiology of paediatric shoulder dislocation: a nationwide study in Italy from 2001 to 2014. Int J Environ Res Public Health. 2020;17(8):2834. Longo UG, Ciuffreda M, Locher J, Casciaro C, Mannering N, Maffulli N, et al. Posterior shoulder instability: a systematic review. Br Med Bull. 2020;134(1):34–53. Hawkins RJ, Mohtadi NGH. Clinical Evaluation of Shoulder Instability. Clin J Sport Med. 1991;1(1):59–64. Albano D, Messina C, Sconfienza LM. Posterior shoulder instability: what to look for. Magn Reson Imaging Clin. 2020;28(2):211–21. Pelet S, Jolles BM, Farron A. Bankart repair for recurrent anterior glenohumeral instability: results at twenty-nine years’ follow-up. J Shoulder Elbow Surg. 2006;15(2):203–7. Wagner SC, Schweitzer ME, Morrison WB, Fenlin JM Jr, Bartolozzi AR. Shoulder instability: accuracy of MR imaging performed after surgery in depicting recurrent injury—initial findings. Radiology. 2002;222(1):196–203. AlSomali K, Kholinne E, Van Nguyen T, Cho C-H, Kwak J-M, Koh K-H, et al. Outcomes and return to sport and work after open Bankart repair for recurrent shoulder instability: a systematic review. Orthop J Sports Med. 2021;9(10):23259671211026907. Golan E, Atte A, Drummond M, Li R, Kane G, Rodosky M, et al. Posterior Labral Tear Extension Concomitant With Shoulder Bankart Injuries Is not Uncommon. Arthrosc Sports Med Rehabilitation. 2022;4(2):e567–73. Burkhart SS, Morgan CD, Kibler WB. The disabled throwing shoulder: spectrum of pathology Part I: pathoanatomy and biomechanics. Arthroscopy: J Arthroscopic Relat Surg. 2003;19(4):404–20. Boileau P, Villalba M, Héry J-Y, Balg F, Ahrens P, Neyton L. Risk factors for recurrence of shoulder instability after arthroscopic Bankart repair. JBJS. 2006;88(8):1755–63. Bottoni CR, Franks BR, Moore JH, DeBerardino TM, Taylor DC, Arciero RA. Operative stabilization of posterior shoulder instability. Am J Sports Med. 2005;33(7):996–1002. Bucha A, Dashottar S, Shukla A. Shoulder MRI in diagnostic evaluation of shoulder joint instability: a comparison with shoulder arthroscopy. Int J Radiol Diagn Imaging. 2019;2(2):23–7. Hurley ET, Matache BA, Wong I, Itoi E, Strauss EJ, Delaney RA, et al. Anterior shoulder instability part I—diagnosis, nonoperative management, and Bankart repair—an international consensus statement. Arthroscopy: J Arthroscopic Relat Surg. 2022;38(2):214–23. e7. Malik AT, Morris J, Bishop JY, Neviaser AS, Khan SN, Cvetanovich GL. Undergoing an arthroscopic procedure prior to shoulder arthroplasty is associated with greater risk of prosthetic joint infection. Arthroscopy: J Arthroscopic Relat Surg. 2021;37(6):1748–54. e1. Trantos IA, Vasiliadis ES, Giannoulis FS, Pappa E, Kakridonis F, Pneumaticos SG. The effect of PRP augmentation of arthroscopic repairs of shoulder rotator cuff tears on postoperative clinical scores and Retear rates: a systematic review and meta-analysis. J Clin Med. 2023;12(2):581. Kompel AJ, Li X, Guermazi A, Murakami AM. Radiographic evaluation of patients with anterior shoulder instability. Curr Rev Musculoskelet Med. 2017;10:425–33. El-Khoury G, Kathol M, Chandler J, Albright J. Shoulder instability: impact of glenohumeral arthrotomography on treatment. Radiology. 1986;160(3):669–73. Zhang P, Li C, Wang W, Zhang B, Miao W, Liu Y. 3.0 T MRI is more recommended to detect acetabular labral tears than MR Arthrography: an updated meta-analysis of diagnostic accuracy. J Orthop Surg Res. 2022;17(1):126. Magee T. Usefulness of unenhanced MRI and MR arthrography of the shoulder in detection of unstable labral tears. Am J Roentgenol. 2015;205(5):1056–60. Kumar N, Prashanth S. Accuracy of MRI in diagnosing rotator cuff and labral tears of shoulder. Int J Orthop. 2020;6(2):01–4. Sheridan K, Kreulen C, Kim S, Mak W, Lewis K, Marder R. Accuracy of magnetic resonance imaging to diagnose superior labrum anterior–posterior tears. Volume 23. Arthroscopy: Knee Surgery, Sports Traumatology; 2015. pp. 2645–50. Baptista E, Malavolta EA, Gracitelli ME, Alvarenga D, Bordalo-Rodrigues M, Ferreira Neto AA, et al. Diagnostic accuracy of MRI for detection of tears and instability of proximallong head of biceps tendon: an evaluation of 100 shoulders compared with arthroscopy. Skeletal Radiol. 2019;48:1723–33. Razmjou H, Fournier-Gosselin S, Christakis M, Pennings A, ElMaraghy A, Holtby R. Accuracy of magnetic resonance imaging in detecting biceps pathology in patients with rotator cuff disorders: comparison with arthroscopy. J Shoulder Elbow Surg. 2016;25(1):38–44. Saied A, Redant C, El-Batouty M, El-Lakkany M, El-Adl W, Anthonissen J, et al. Accuracy of magnetic resonance studies in the detection of chondral and labral lesions in femoroacetabular impingement: systematic review and meta-analysis. BMC Musculoskelet Disord. 2017;18:1–16. 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. 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16:37:22","extension":"html","order_by":10,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":79781,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7584450/v1/6cb2126e31011d564b15f5a7.html"},{"id":95662029,"identity":"2b852d01-a93f-4ba2-9630-501279cafd0a","added_by":"auto","created_at":"2025-11-11 16:37:05","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":540649,"visible":true,"origin":"","legend":"\u003cp\u003eArthroscopy of the shoulder using a standard portal to evaluate posterior labral tear in a patient who had a normal appearance of the posterior labrum on axial MRI.\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7584450/v1/6d9526b2880842dd8acfb299.jpeg"},{"id":95662391,"identity":"50a2885c-bf5d-4901-9713-968d93ba08d6","added_by":"auto","created_at":"2025-11-11 16:37:28","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":501414,"visible":true,"origin":"","legend":"\u003cp\u003eAxial T2-weighted MRI scan of the shoulder, demonstrating evaluation for a possible labral tear.\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7584450/v1/c252ce44865ee29d4457e7e8.jpeg"},{"id":95662014,"identity":"ef94f029-b0a2-4ce0-aa4a-a62a450d3f17","added_by":"auto","created_at":"2025-11-11 16:37:03","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":372918,"visible":true,"origin":"","legend":"\u003cp\u003eCT Scan 3D. Reconstruction of the glenoid without the humeral head to evaluate glenoid defects and a schematic representation for assessing the anteroinferior to posteroinferior region for labrum tear.\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7584450/v1/7b1d1af037cc4ec2495f3276.jpeg"},{"id":108804176,"identity":"41c83032-47de-43da-96ec-dfc906f1f378","added_by":"auto","created_at":"2026-05-08 15:17:11","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1635102,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7584450/v1/22717881-7e44-4cbb-bfcc-1ebecd4004b5.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Preoperative Evaluation for Posterior Labral Tears in Anterior Shoulder Instability: Diagnostic Efficacy of MRI","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eThe glenohumeral joint is the most commonly dislocated joint in the human body, accounting for approximately 50% of all joint dislocations and subluxations (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). In the United States, an average of 25.2 per 100,000 individuals experience shoulder dislocations annually, with the highest prevalence among young men aged 14\u0026ndash;19 and those involved in military activities or throwing sports (\u003cspan additionalcitationids=\"CR3\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). Shoulder instability is classified by its cause, direction, onset, and degree, with unidirectional instability defined as either anterior or posterior. Approximately 95% of cases involve anterior or anterior-inferior instability, while posterior instability is less common, representing about 10% of cases (\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\u003eShoulder instability often leads to dysfunction of the capsule, labrum, glenohumeral ligaments, rotator cuff, and surrounding muscles, potentially causing damage to the humeral head or glenoid process (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). Anterior instability is commonly associated with anterior-inferior labrum tears (Bankart lesions) (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Posterior labrum tears, though less frequently recognized, may also occur with anterior instability (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). Burkhardt et al. hypothesized that 360-degree labral injuries, affecting the anterior labrum, could also involve the posterior labrum (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). Recent studies suggest that increased pressure on the posterior labrum following anterior dislocation might contribute to unrecognized injuries during Bankart repair (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eTimely identification and treatment of labral injuries are critical for successful management of shoulder instability, requiring thorough clinical and diagnostic evaluation. Advances in imaging techniques, such as computed tomography and magnetic resonance imaging (MRI), along with arthroscopic surgical methods, have improved diagnostic accuracy and treatment outcomes (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eSurgical intervention is often recommended for patients with a high risk of recurrent instability. Depending on the presence of labral tears or glenoid bone defects, procedures like open or arthroscopic Bankart repair may be required (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e). While arthroscopy is the gold standard for diagnosing shoulder injuries due to its ability to directly visualize intra-articular structures with high magnification, it carries risks such as infection, damage to adjacent structures, and anesthetic complications (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eMRI is a non-ionizing, non-contrast imaging modality with high sensitivity for detecting soft tissue injuries, particularly anterior labral tears (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e). However, controversy exists between radiologists and shoulder surgeons regarding the interpretation of MRI findings for posterior labral injuries. This study aims to evaluate the diagnostic accuracy of MRI compared to arthroscopy for detecting posterior labral tears in patients with anterior shoulder instability undergoing arthroscopic Bankart repair.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cp\u003e This retrospective cohort study was conducted after receiving ethical approval from the Medical Sciences Ethics Committee [REC.1403.227]. The study included 300 patients with traumatic anterior shoulder instability who underwent arthroscopic Bankart repair between December 2016 and December 2023.\u003c/p\u003e\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eInclusion and Exclusion Criteria\u003c/h2\u003e\u003cp\u003ePatients were excluded if they had cardiac dysfunction, brachial plexus issues, systemic diseases (e.g., rheumatoid arthritis, lupus erythematosus), connective tissue disorders, age\u0026thinsp;\u0026gt;\u0026thinsp;50 or \u0026lt;\u0026thinsp;16 years, unavailable or low-quality MRI scans, a history of prior glenohumeral surgery, or atraumatic/multidirectional instability. Of the 300 patients initially considered, 265 met the eligibility criteria.\u003c/p\u003e\u003cp\u003eAll patients underwent a clinical examination performed by senior orthopedists and preoperative MRI (Siemens 1.5-T MRI machine, T2-weighted axial sequences) as part of their evaluation.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eSurgical Procedure and Arthroscopic Evaluation\u003c/h3\u003e\n\u003cp\u003eAfter suprascapular regional block anesthesia, all patients underwent shoulder arthroscopy in the beach-chair position performed by a senior orthopedist using four standard portals (posterior, anterior, anterolateral, and lateral). In addition to addressing anterior instability, the posterior glenoid labrum was systematically evaluated for tears during arthroscopy (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\n\u003ch3\u003eMRI Interpretation\u003c/h3\u003e\n\u003cp\u003eMRI scans were reviewed independently by two fellowship-trained orthopedic surgeons and one musculoskeletal (MSK) radiologist specializing in sports medicine. The axial T2-weighted images were used to identify posterior labral tears (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). A tear was defined as any injury posterior to a vertical line connecting the 12 o\u0026rsquo;clock and 6 o\u0026rsquo;clock positions on the glenoid labrum (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Discrepancies in diagnoses were resolved by majority opinion. MRI findings were classified as either positive or negative.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\n\u003ch3\u003eData Collection\u003c/h3\u003e\n\u003cp\u003eDemographic and clinical data, including age, gender, side involved, number and episodes of dislocation, duration of symptoms, socioeconomic status, and cause of trauma, were extracted from electronic medical records. Diagnoses of posterior labral tears were recorded separately and blindly for MRI and arthroscopy findings.\u003c/p\u003e\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003eStatistical Analysis\u003c/h2\u003e\u003cp\u003eData were analyzed using SPSS version 26. Descriptive statistics (mean, standard deviation, frequency, and percentage) were used to summarize patient characteristics. Comparative analyses were performed using Fisher\u0026rsquo;s exact test and paired t-tests, as appropriate. Diagnostic performance metrics, including sensitivity (TP/(TP\u0026thinsp;+\u0026thinsp;FN)), specificity (TN/(FP\u0026thinsp;+\u0026thinsp;TN)), positive predictive value (PPV: TP/(TP\u0026thinsp;+\u0026thinsp;FP)), negative predictive value (NPV: TN/(FN\u0026thinsp;+\u0026thinsp;TN)), and overall accuracy ((TP\u0026thinsp;+\u0026thinsp;TN)/Total), were calculated.\u003c/p\u003e\u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003eA total of 265 patients were included in the study. Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e depicts the demographic information of the patients.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003edemographic data of patient with anterior shoulder instability (n\u0026thinsp;=\u0026thinsp;265)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"2\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003evalue\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSex (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e210\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003efemale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e55\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge (mean-SD)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e29.1\u0026thinsp;\u0026plusmn;\u0026thinsp;6.38\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSide involved (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLeft\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e116\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRight\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e149\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNumber of dislocations\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u0026gt;3 times\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e143\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e=\u0026lt;3 times\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e122\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDuration of symptoms\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e13.38\u0026thinsp;\u0026plusmn;\u0026thinsp;5.89\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSocial economic\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGood\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e135\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003epoor\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e130\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCouse of trouma\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAccident\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e87\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSport\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e127\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFalling down\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e51\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eEach patient underwent MRI evaluation for the detection of posterior labral tears, interpreted independently by two orthopedic surgeons and one radiologist. The findings were compared with the arthroscopy results, which served as the gold standard. Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e demonstrates the comparison.\u003c/p\u003e\u003cp\u003eThe diagnostic performance of MRI for detecting labral tears was evaluated in terms of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). The results are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e\u003cp\u003eThe interclass correlation coefficient (ICC) was calculated to assess the agreement among the three specialists. The ICC was 0.847, indicating good reliability. The 95% confidence interval was 0.812 to 0.876 (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), suggesting a high degree of consistency in the MRI interpretations for posterior labral tears across the radiologist and orthopedic surgeons.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003ecomparison of MRI finding (Orthopedic Surgeon MRI Reading and Radiologic Report) with arthroscopy results\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"3\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePositive for labral tear\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eNegative for labral tear\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMRI report by the orthopedic surgeon 1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e62\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e203\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMRI report by the orthopedic surgeon 2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e61\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e204\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMRI report by the radiologist\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e72\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e193\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMRI report by the cohort\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e65\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e200\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eArthroscopy (gold standard)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e109\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e156\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003esensitivity, specificity, PPV, NPV and accuracy of the MRI readings\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003esensitivity\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003especificity\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePPV\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eNPV\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eaccuracy\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRadiologist\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e46.8%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e86.5%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e70.8%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e69.9%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e70.2%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOrthopedic surgeon 1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e44.0%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e91.0%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e77.4%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e70.0%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e71.7%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOrthopedic surgeon 2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e43.1%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e91.0%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e77.0%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e69.6%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e71.3%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCohort\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e56.9%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e98.1%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e95.4%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e76.5%\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e81.1%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eShoulder labrum tears and instability are common presentations in emergency departments. Before the introduction of MRI, invasive diagnostic methods such as arthrography, double contrast arthrography-computed tomography, and arthroscopy were the primary tools for evaluating intra-articular pathologies associated with these conditions. MRI, a non-invasive method, has become the preferred choice for the clinical diagnosis of shoulder injuries due to its superior soft tissue contrast, high spatial resolution, and ability to provide multi-parametric evaluation of morphological changes in the injured shoulder joint. Since the 1980s, MRI has been utilized to diagnose shoulder pathologies, but its diagnostic accuracy for shoulder instability lesions remains limited. However, advancements in imaging technology have led to significant improvements in preoperative diagnosis (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe unique anatomy of the shoulder joint makes it difficult to visualize posterior labrum tears in the true sagittal plane through MRI, contributing to the uncertainty regarding MRI's diagnostic accuracy for shoulder instability. High-quality evidence-based research is needed to improve our understanding of shoulder injury diagnosis. In our study, MRI showed low sensitivity (22.2%) but high specificity (100%) for diagnosing posterior shoulder labrum tears. These findings contrast with those of Sheridan et al., who reported a sensitivity of 66% and specificity of 77% for diagnosing superior labrum anterior-posterior (SLAP) lesions (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e). Kumar et al. (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e) also found that MRI had 100% sensitivity for rotator cuff and Bankart tears but only 60% sensitivity for diagnosing labral lesions, highlighting the limited accuracy for posterior labrum injuries.\u003c/p\u003e\u003cp\u003eArthroscopy remains the gold standard for diagnosing shoulder lesions, but MRI and arthroscopy complement each other in diagnosing shoulder instability (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e). In line with our study, Meg et al. reported 89% sensitivity and 100% specificity for MRI in diagnosing anterior labrum tears (\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e). While some studies report higher sensitivity than our findings, Golan et al. (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e) demonstrated that posterior extension of Bankart lesions in anterior shoulder dislocation occurs in approximately 18.5% of cases, emphasizing the importance of evaluating the posterior labrum on MRI arthrograms. The variability in findings across studies may stem from differences in imaging systems, MRI interpretation methods, and study design. Despite these discrepancies, most sources agree that clinical and imaging findings should be integrated for an accurate diagnosis.\u003c/p\u003e\u003cp\u003eOur study also found that MRI had a positive predictive value (PPV) of 100% and a negative predictive value (NPV) of 52.3% for diagnosing posterior labrum tears. In contrast, Sheridan et al. (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e) reported a PPV of 24% and an NPV of 95%, reflecting the inconsistencies in MRI\u0026rsquo;s diagnostic capabilities. Baptista et al. (\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e) found PPVs between 86% and 88% for various shoulder tears, suggesting that MRI alone may miss some cases, making clinical correlation essential for surgical decision-making. The differences in study results may be attributed to factors such as the degree and location of tears, the MRI cut used, and the skill of the MRI interpreter. More research is needed to better define these variables.\u003c/p\u003e\u003cp\u003eOur analysis showed that MRI had a diagnostic accuracy of 58% for diagnosing posterior labrum tears, which is consistent with other studies that report moderate accuracy for upper labrum tears (76%) (\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e) and partial to complete tendon ruptures (57\u0026ndash;92%) (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e). A meta-analysis comparing arthrography with MRI found that arthrography had higher diagnostic accuracy for labral lesions (\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e). Despite the lower diagnostic accuracy in our study, it\u0026rsquo;s important to note that the anatomical positioning of the posterior labrum contributes to the difficulty in detecting tears via MRI. Additionally, differences in MRI equipment, interpreter experience, and injury type could explain the discrepancies in study outcomes.\u003c/p\u003e\n\u003ch3\u003eLimitations of the Study:\u003c/h3\u003e\n\u003cp\u003eThis study\u0026rsquo;s sample size was limited due to time and financial constraints, which may affect the generalizability of the results. Future studies with larger sample sizes are recommended. Additionally, the cross-sectional design of the study restricts causal inference, and the use of convenience sampling may limit generalizability. Longitudinal studies with larger, more diverse patient populations could provide more accurate, generalizable findings.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eThe findings of this study suggest that MRI alone should not be relied upon for diagnosing posterior labrum tears in patients with anterior shoulder instability, as its sensitivity and specificity for detecting these injuries are limited. Failure to address posterior labrum tears during surgery for anterior labrum tears may contribute to treatment failure. Therefore, it is crucial that shoulder arthroscopy not only evaluates the anterior labrum but also includes a thorough examination of the posterior labrum, with surgeons being prepared to repair any posterior labral tears identified during the procedure.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003e\u003cb\u003eMRI\u003c/b\u003e\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eMagnetic Resonance Imaging\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003e\u003cb\u003ePPV\u003c/b\u003e\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003ePositive Predictive Value\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003e\u003cb\u003eNPV\u003c/b\u003e\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eNegative Predictive Value\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003e\u003cb\u003eICC\u003c/b\u003e\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eIntraclass Correlation Coefficient\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis retrospective cohort study was conducted after receiving ethical approval from the Shahid Beheshti University of Medical Sciences Ethics Committee [IR.SBMU.MSP.REC.1403.227]. We confirm that all methods were performed in accordance with the Declaration of Helsinki and relevant institutional guidelines and regulations. Due to the retrospective nature of the study, the need for obtaining informed consent was waived by the Shahid Beheshti University of Medical Sciences Institutional Review Board (IRB).\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\u003eAvailability of data and materials:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets generated and/or analysed during the current study are not publicly available but are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting Interests:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors' contributions:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAmir Bisadi: Data collection, manuscript drafting.\u003c/p\u003e\n\u003cp\u003eMehdi Rahimi: Statistical analysis, data interpretation.\u003c/p\u003e\n\u003cp\u003eFatemeh Abbasi: Literature review, manuscript drafting and editing.\u003c/p\u003e\n\u003cp\u003eMohammad H. Mahrooz: Data collection, critical revision.\u003c/p\u003e\n\u003cp\u003eMorteza Gholipour: Study conception, surgical procedures, supervision, and corresponding author.\u003c/p\u003e\n\u003cp\u003eAll authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors would like to thank the staff of Akhtar Orthopedic Hospital for their assistance in data collection and patient management.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability:\u003c/strong\u003e available The datasets generated and/or analysed during the current study are not publicly available but are available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eZandi S, Rajabi R, Minoonejad H, Mohseni-Bandpei M. Upper quarter functional stability in female volleyball players with and without anterior shoulder instability, with consideration of arm dominance. Archives Rehabilitation. 2016;16(4):346\u0026ndash;55.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBecker B, Spadafore S, Oberle L, Spittler J, Khodaee M. Epidemiology of shoulder dislocation treated at emergency departments in the United States Between 1997 and 2021. Orthop J sports Med. 2024;12(3):23259671241234930.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLongo UG, Salvatore G, Locher J, Ruzzini L, Candela V, Berton A, et al. Epidemiology of paediatric shoulder dislocation: a nationwide study in Italy from 2001 to 2014. Int J Environ Res Public Health. 2020;17(8):2834.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLongo UG, Ciuffreda M, Locher J, Casciaro C, Mannering N, Maffulli N, et al. Posterior shoulder instability: a systematic review. Br Med Bull. 2020;134(1):34\u0026ndash;53.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHawkins RJ, Mohtadi NGH. Clinical Evaluation of Shoulder Instability. Clin J Sport Med. 1991;1(1):59\u0026ndash;64.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAlbano D, Messina C, Sconfienza LM. Posterior shoulder instability: what to look for. Magn Reson Imaging Clin. 2020;28(2):211\u0026ndash;21.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePelet S, Jolles BM, Farron A. Bankart repair for recurrent anterior glenohumeral instability: results at twenty-nine years\u0026rsquo; follow-up. J Shoulder Elbow Surg. 2006;15(2):203\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWagner SC, Schweitzer ME, Morrison WB, Fenlin JM Jr, Bartolozzi AR. Shoulder instability: accuracy of MR imaging performed after surgery in depicting recurrent injury\u0026mdash;initial findings. Radiology. 2002;222(1):196\u0026ndash;203.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAlSomali K, Kholinne E, Van Nguyen T, Cho C-H, Kwak J-M, Koh K-H, et al. Outcomes and return to sport and work after open Bankart repair for recurrent shoulder instability: a systematic review. Orthop J Sports Med. 2021;9(10):23259671211026907.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGolan E, Atte A, Drummond M, Li R, Kane G, Rodosky M, et al. Posterior Labral Tear Extension Concomitant With Shoulder Bankart Injuries Is not Uncommon. Arthrosc Sports Med Rehabilitation. 2022;4(2):e567\u0026ndash;73.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBurkhart SS, Morgan CD, Kibler WB. The disabled throwing shoulder: spectrum of pathology Part I: pathoanatomy and biomechanics. Arthroscopy: J Arthroscopic Relat Surg. 2003;19(4):404\u0026ndash;20.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBoileau P, Villalba M, H\u0026eacute;ry J-Y, Balg F, Ahrens P, Neyton L. Risk factors for recurrence of shoulder instability after arthroscopic Bankart repair. JBJS. 2006;88(8):1755\u0026ndash;63.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBottoni CR, Franks BR, Moore JH, DeBerardino TM, Taylor DC, Arciero RA. Operative stabilization of posterior shoulder instability. Am J Sports Med. 2005;33(7):996\u0026ndash;1002.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBucha A, Dashottar S, Shukla A. Shoulder MRI in diagnostic evaluation of shoulder joint instability: a comparison with shoulder arthroscopy. Int J Radiol Diagn Imaging. 2019;2(2):23\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHurley ET, Matache BA, Wong I, Itoi E, Strauss EJ, Delaney RA, et al. Anterior shoulder instability part I\u0026mdash;diagnosis, nonoperative management, and Bankart repair\u0026mdash;an international consensus statement. Arthroscopy: J Arthroscopic Relat Surg. 2022;38(2):214\u0026ndash;23. e7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMalik AT, Morris J, Bishop JY, Neviaser AS, Khan SN, Cvetanovich GL. Undergoing an arthroscopic procedure prior to shoulder arthroplasty is associated with greater risk of prosthetic joint infection. Arthroscopy: J Arthroscopic Relat Surg. 2021;37(6):1748\u0026ndash;54. e1.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTrantos IA, Vasiliadis ES, Giannoulis FS, Pappa E, Kakridonis F, Pneumaticos SG. The effect of PRP augmentation of arthroscopic repairs of shoulder rotator cuff tears on postoperative clinical scores and Retear rates: a systematic review and meta-analysis. J Clin Med. 2023;12(2):581.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKompel AJ, Li X, Guermazi A, Murakami AM. Radiographic evaluation of patients with anterior shoulder instability. Curr Rev Musculoskelet Med. 2017;10:425\u0026ndash;33.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eEl-Khoury G, Kathol M, Chandler J, Albright J. Shoulder instability: impact of glenohumeral arthrotomography on treatment. Radiology. 1986;160(3):669\u0026ndash;73.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZhang P, Li C, Wang W, Zhang B, Miao W, Liu Y. 3.0 T MRI is more recommended to detect acetabular labral tears than MR Arthrography: an updated meta-analysis of diagnostic accuracy. J Orthop Surg Res. 2022;17(1):126.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMagee T. Usefulness of unenhanced MRI and MR arthrography of the shoulder in detection of unstable labral tears. Am J Roentgenol. 2015;205(5):1056\u0026ndash;60.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKumar N, Prashanth S. Accuracy of MRI in diagnosing rotator cuff and labral tears of shoulder. Int J Orthop. 2020;6(2):01\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSheridan K, Kreulen C, Kim S, Mak W, Lewis K, Marder R. Accuracy of magnetic resonance imaging to diagnose superior labrum anterior\u0026ndash;posterior tears. Volume 23. Arthroscopy: Knee Surgery, Sports Traumatology; 2015. pp. 2645\u0026ndash;50.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBaptista E, Malavolta EA, Gracitelli ME, Alvarenga D, Bordalo-Rodrigues M, Ferreira Neto AA, et al. Diagnostic accuracy of MRI for detection of tears and instability of proximallong head of biceps tendon: an evaluation of 100 shoulders compared with arthroscopy. Skeletal Radiol. 2019;48:1723\u0026ndash;33.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRazmjou H, Fournier-Gosselin S, Christakis M, Pennings A, ElMaraghy A, Holtby R. Accuracy of magnetic resonance imaging in detecting biceps pathology in patients with rotator cuff disorders: comparison with arthroscopy. J Shoulder Elbow Surg. 2016;25(1):38\u0026ndash;44.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSaied A, Redant C, El-Batouty M, El-Lakkany M, El-Adl W, Anthonissen J, et al. Accuracy of magnetic resonance studies in the detection of chondral and labral lesions in femoroacetabular impingement: systematic review and meta-analysis. BMC Musculoskelet Disord. 2017;18:1\u0026ndash;16.\u003c/span\u003e\u003c/li\u003e\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":"Posterior labral tear, Shoulder arthroscopy, sensitivity, specificity","lastPublishedDoi":"10.21203/rs.3.rs-7584450/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7584450/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eShoulder arthroscopy remains the gold standard for diagnosing shoulder instability. While magnetic resonance imaging (MRI) demonstrates consistent accuracy in detecting anterior labral injuries associated with glenohumeral instability, discrepancies persist between radiologists and orthopedic surgeons regarding the interpretation of MRI findings for posterior labral tears. This study aims to evaluate the diagnostic efficacy of preoperative MRI in identifying posterior labral tears in patients with anterior shoulder instability undergoing arthroscopic Bankart repair.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA retrospective study was conducted between December 2016 and December 2023, involving 265 patients with traumatic anterior glenohumeral instability who were candidates for Bankart lesion repair. The diagnostic performance of MRI in detecting posterior labral lesions was assessed against shoulder arthroscopy, considered the gold standard. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated based on MRI findings interpreted by a radiologist and two orthopedic surgeons independently.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe mean age of the patients was 29.1 years. The sensitivity of preoperative MRI for diagnosing posterior labral tears was 46.8% for the radiologist and 44.0% and 43.1% for the two orthopedic surgeons. Specificity was 86.5% for the radiologist and 91.0% for both surgeons. The PPV values were 70.8% (radiologist), 77.4% (surgeon 1), and 77.0% (surgeon 2), while the NPV values were 69.9%, 70.0%, and 69.6%, respectively. The overall accuracy of MRI in diagnosing posterior labral tears was reported as 70.2% (radiologist), 71.7% (surgeon 1), and 71.3% (surgeon 2).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMRI has limited accuracy in diagnosing posterior labral lesions, with shoulder arthroscopy remaining the gold standard. MRI and arthroscopy should be viewed as complementary tools in the evaluation of shoulder instability.\u003c/p\u003e","manuscriptTitle":"Preoperative Evaluation for Posterior Labral Tears in Anterior Shoulder Instability: Diagnostic Efficacy of MRI","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-11 16:19:14","doi":"10.21203/rs.3.rs-7584450/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":"4970434f-e3f1-4b97-a52d-95579c7f56b9","owner":[],"postedDate":"November 11th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-05-04T10:40:25+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-11 16:19:14","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7584450","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7584450","identity":"rs-7584450","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}