{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T06:15:55Z","timestamp":1788243355158,"version":"build-2803163510"},"reference-count":34,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T00:00:00Z","timestamp":1787961600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Clin. Med.","JCM"],"abstract":"<jats:p>Magnetic resonance imaging (MRI) is universally recognized as the gold standard for evaluating anterior cruciate ligament (ACL) injuries. However, differentiating partial tears from complete ruptures using the standard sagittal plane remains a diagnostic challenge. The oblique coronal orientation of the ACL often leads to volume averaging artifacts and inaccurate interpretations. While axial imaging offers a favorable alternative, distal tears near the tibial attachment are frequently missed. This review synthesizes current concepts in the anatomical and radiological evaluation of the ACL and introduces the \u201cNamaste sign,\u201d a novel and proposed preliminary imaging marker observed on coronal MRI to help assess ACL integrity. Grounded in the distinct native double-bundle architecture of the ACL, the Namaste sign utilizes the coronal plane to evaluate the transverse relationship and physiological tension of the anteromedial and posterolateral bundles. In a normal knee, these bundles converge symmetrically from their distinct tibial footprints and maintain tight contact with the lateral femoral condyle, mimicking hands pressed together in a traditional \u201cNamaste\u201d gesture. This article details the anatomical basis of this sign, provides a systematic method for its identification, and illustrates how morphological variations such as \u201cbroken hands,\u201d \u201cabsent hands,\u201d \u201cabsent proximal hug,\u201d or \u201cseparation of hands\u201d may correspond to specific ACL lesions. As a preliminary conceptual marker, the Namaste sign is intended to serve as an educational adjunct to combined three-plane evaluation rather than a standalone diagnostic criterion. Notably, this sign is not applicable to postoperative ACL reconstructions. A preliminary pilot study of 50 cases utilizing thin-slice MRI (\u22643 mm) demonstrated nearly 100% visibility of the sign, 98% diagnostic accuracy, and almost perfect inter-observer agreement between two radiologists with more than 10 years of experience (Cohen\u2019s kappa = 0.92). However, future diagnostic studies with rigorous arthroscopic reference standards are required to establish its clinical performance and reliability in larger cohorts.<\/jats:p>","DOI":"10.3390\/jcm15176699","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T05:45:13Z","timestamp":1788241513000},"page":"6699","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The \u201cNamaste Sign\u201d\u2014A Novel Coronal MRI Marker for the Evaluation of Anterior Cruciate Ligament Integrity"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-2956-0270","authenticated-orcid":false,"given":"Shashank","family":"Chapala","sequence":"first","affiliation":[{"name":"Department of Radiology, AIG Hospital, Hyderabad 500032, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7998-2980","authenticated-orcid":false,"given":"Rajesh","family":"Botchu","sequence":"additional","affiliation":[{"name":"Department of Musculoskeletal Radiology, Royal Orthopaedic Hospital, Bristol Road South, Northfield, Birmingham B31 2AP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7060-211X","authenticated-orcid":false,"given":"Hasaam","family":"Uldin","sequence":"additional","affiliation":[{"name":"Department of Musculoskeletal Radiology, Royal Orthopaedic Hospital, Bristol Road South, Northfield, Birmingham B31 2AP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meili Jade Temsin Leung","family":"Chew","sequence":"additional","affiliation":[{"name":"Sir Seewoosagur Ramgoolam Medical College, Dalgotiere 80203, Mauritius"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6301-1776","authenticated-orcid":false,"given":"Kapil","family":"Shirodkar","sequence":"additional","affiliation":[{"name":"Department of Musculoskeletal Radiology, Royal Lancaster Infirmary, Lancaster LA1 4RP, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-9152-0484","authenticated-orcid":false,"given":"Sang Bum","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Radiology, UT Southwestern Medical Center, Dallas, TX 75390, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anoop Venkatapura","family":"Bylaswamy","sequence":"additional","affiliation":[{"name":"Department of Radiology, UT Southwestern Medical Center, Dallas, TX 75390, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0718-3802","authenticated-orcid":false,"given":"Avneesh","family":"Chhabra","sequence":"additional","affiliation":[{"name":"Department of Radiology, UT Southwestern Medical Center, Dallas, TX 75390, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2135","DOI":"10.1056\/NEJMcp0804745","article-title":"Anterior cruciate ligament tear","volume":"359","author":"Spindler","year":"2008","journal-title":"N. 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