{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T13:24:52Z","timestamp":1777901092445,"version":"3.51.4"},"reference-count":28,"publisher":"Springer Science and Business Media LLC","issue":"4","license":[{"start":{"date-parts":[[2025,8,23]],"date-time":"2025-08-23T00:00:00Z","timestamp":1755907200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.springernature.com\/gp\/researchers\/text-and-data-mining"},{"start":{"date-parts":[[2025,8,23]],"date-time":"2025-08-23T00:00:00Z","timestamp":1755907200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.springernature.com\/gp\/researchers\/text-and-data-mining"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Eur Spine J"],"published-print":{"date-parts":[[2026,4]]},"DOI":"10.1007\/s00586-025-09286-x","type":"journal-article","created":{"date-parts":[[2025,8,23]],"date-time":"2025-08-23T06:28:40Z","timestamp":1755930520000},"page":"1943-1953","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The atlantoaxial distance ratio (AADR): proposal and validation of a novel radiographic parameter for the evaluation vertical atlantoaxial dislocation in a preliminary descriptive study"],"prefix":"10.1007","volume":"35","author":[{"given":"Bo","family":"Yuan","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zheng","family":"Xu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yin","family":"Zhao","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiongsheng","family":"Chen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shengyuan","family":"Zhou","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2025,8,23]]},"reference":[{"issue":"4","key":"9286_CR1","doi-asserted-by":"publisher","first-page":"1199","DOI":"10.1111\/os.12734","volume":"12","author":"T Mingsheng","year":"2020","unstructured":"Mingsheng T, Long G, Ping Y et al (2020) New classification and its value evaluation for atlantoaxial dislocation. Orthop Surg 12(4):1199\u20131204","journal-title":"Orthop Surg"},{"key":"9286_CR2","doi-asserted-by":"publisher","first-page":"156","DOI":"10.1016\/j.wneu.2016.07.097","volume":"95","author":"P Salunke","year":"2016","unstructured":"Salunke P, Sahoo SK, Deepak AN, Khandelwal NK (2016) Redefining congenital atlantoaxial dislocation: objective assessment in each plane before and after operation. World Neurosurg 95:156\u2013164","journal-title":"World Neurosurg"},{"issue":"3","key":"9286_CR3","doi-asserted-by":"publisher","first-page":"E13","DOI":"10.3171\/2022.12.FOCUS22634","volume":"54","author":"A Shah","year":"2023","unstructured":"Shah A, Vutha R, Prasad A, Goel A (2023) Central or axial atlantoaxial dislocation and craniovertebral junction alterations: a review of 393 patients treated over 12 years. Neurosurg Focus 54(3):E13","journal-title":"Neurosurg Focus"},{"issue":"3","key":"9286_CR4","doi-asserted-by":"publisher","first-page":"241","DOI":"10.1007\/s005860050166","volume":"8","author":"S Ramar\u00e9","year":"1999","unstructured":"Ramar\u00e9 S, Lazennec JY, Camelot C, Saillant G, Hansen S, Trabelsi R (1999) Vertical atlantoaxial dislocation. Eur Spine J 8(3):241\u2013243","journal-title":"Eur Spine J"},{"issue":"6","key":"9286_CR5","doi-asserted-by":"publisher","first-page":"704","DOI":"10.1016\/j.jocn.2004.03.043","volume":"12","author":"M Payer","year":"2005","unstructured":"Payer M, Wetzel S, Kelekis A, Jenny B (2005) Traumatic vertical atlantoaxial dislocation. J Clin Neurosci 12(6):704\u2013706","journal-title":"J Clin Neurosci"},{"issue":"7","key":"9286_CR6","doi-asserted-by":"publisher","first-page":"1239","DOI":"10.1007\/s00264-020-04593-y","volume":"44","author":"S Liao","year":"2020","unstructured":"Liao S, Jung MK, H\u00f6rnig L, Gr\u00fctzner PA, Kreinest M (2020) Injuries of the upper cervical spine-how can instability be identified. Int Orthop 44(7):1239\u20131253","journal-title":"Int Orthop"},{"issue":"6","key":"9286_CR7","doi-asserted-by":"publisher","first-page":"863","DOI":"10.3171\/jns.1997.87.6.0863","volume":"87","author":"AT Casey","year":"1997","unstructured":"Casey AT, Crockard HA, Stevens J (1997) Vertical translocation. Part II. Outcomes after surgical treatment of rheumatoid cervical myelopathy. J Neurosurg 87(6):863\u2013869","journal-title":"J Neurosurg"},{"issue":"3","key":"9286_CR8","doi-asserted-by":"publisher","first-page":"273","DOI":"10.3171\/spi.2004.1.3.0273","volume":"1","author":"LF Gonzalez","year":"2004","unstructured":"Gonzalez LF, Fiorella D, Crawford NR et al (2004) Vertical atlantoaxial distraction injuries: radiological criteria and clinical implications. J Neurosurg Spine 1(3):273\u2013280","journal-title":"J Neurosurg Spine"},{"issue":"4","key":"9286_CR9","doi-asserted-by":"publisher","first-page":"1098","DOI":"10.1007\/s00586-015-4370-7","volume":"25","author":"P Salunke","year":"2016","unstructured":"Salunke P, Sahoo SK, Futane S, Deepak AN, Khandelwal NK (2016) Atlas shrugged\u2019: congenital lateral angular irreducible atlantoaxial dislocation: a case series of complex variant and its management. Eur Spine J 25(4):1098\u20131108","journal-title":"Eur Spine J"},{"issue":"1","key":"9286_CR10","doi-asserted-by":"publisher","first-page":"324","DOI":"10.1186\/s12893-021-01321-0","volume":"21","author":"S Zhou","year":"2021","unstructured":"Zhou S, Yuan B, Liu W, Tang Y, Chen X, Jia L (2021) Three-dimensional reduction method with a modified C2 isthmus screw in irreducible atlantoaxial dislocation: a technical note. BMC Surg 21(1):324","journal-title":"BMC Surg"},{"issue":"2","key":"9286_CR11","doi-asserted-by":"publisher","first-page":"133","DOI":"10.1177\/028418518402500209","volume":"25","author":"I Redlund-Johnell","year":"1984","unstructured":"Redlund-Johnell I, Pettersson H (1984) Vertical dislocation of the C1 and C2 vertebrae in rheumatoid arthritis. Acta Radiol Diagn (Stockh) 25(2):133\u2013141","journal-title":"Acta Radiol Diagn (Stockh)"},{"issue":"1","key":"9286_CR12","doi-asserted-by":"publisher","first-page":"4","DOI":"10.1097\/BSD.0b013e31804856d7","volume":"21","author":"AG Kulkarni","year":"2008","unstructured":"Kulkarni AG, Goel AH (2008) Vertical atlantoaxial index: a new craniovertebral radiographic index. J Spinal Disord Tech 21(1):4\u201310","journal-title":"J Spinal Disord Tech"},{"issue":"Suppl 2","key":"9286_CR13","doi-asserted-by":"publisher","first-page":"114","DOI":"10.1227\/NEU.0b013e31827765e0","volume":"72","author":"N Theodore","year":"2013","unstructured":"Theodore N, Aarabi B, Dhall SS et al (2013) The diagnosis and management of traumatic atlanto-occipital dislocation injuries. Neurosurgery 72(Suppl 2):114\u2013126","journal-title":"Neurosurgery"},{"issue":"18","key":"9286_CR14","doi-asserted-by":"publisher","first-page":"1234","DOI":"10.1097\/BRS.0000000000004007","volume":"46","author":"O Leonova","year":"2021","unstructured":"Leonova O, Baykov E, Sanginov A, Krutko A (2021) Cervical disc degeneration and vertebral endplate defects after the fused operation. Spine (Phila Pa 1976) 46(18):1234\u20131240","journal-title":"Spine (Phila Pa 1976)"},{"issue":"17","key":"9286_CR15","doi-asserted-by":"publisher","first-page":"1873","DOI":"10.1097\/00007632-200109010-00011","volume":"26","author":"CW Pfirrmann","year":"2001","unstructured":"Pfirrmann CW, Metzdorf A, Zanetti M, Hodler J, Boos N (2001) Magnetic resonance classification of lumbar intervertebral disc degeneration. Spine (Phila Pa 1976) 26(17):1873\u20131878","journal-title":"Spine (Phila Pa 1976)"},{"issue":"10","key":"9286_CR16","doi-asserted-by":"publisher","first-page":"2167","DOI":"10.1007\/s00586-013-2841-2","volume":"22","author":"ML Pissonnier","year":"2013","unstructured":"Pissonnier ML, Lazennec JY, Renoux J, Rousseau MA (2013) Trauma of the upper cervical spine: focus on vertical atlantoaxial dislocation. Eur Spine J 22(10):2167\u20132175","journal-title":"Eur Spine J"},{"key":"9286_CR17","doi-asserted-by":"publisher","first-page":"59","DOI":"10.1016\/j.wneu.2020.08.045","volume":"144","author":"P Salunke","year":"2020","unstructured":"Salunke P, Singh A, Karthigeyan M (2020) Technique of C2 subfacetal screw in patients with high-riding vertebral artery. World Neurosurg 144:59","journal-title":"World Neurosurg"},{"issue":"4","key":"9286_CR18","doi-asserted-by":"publisher","first-page":"305","DOI":"10.1111\/j.1757-7861.2009.00049.x","volume":"1","author":"DJ Hao","year":"2009","unstructured":"Hao DJ, He BR, Wu QN (2009) One-stage anterior release and reduction with posterior fusion for treatment of irreducible atlantoaxial dislocation. Orthop Surg 1(4):305\u2013310","journal-title":"Orthop Surg"},{"issue":"6","key":"9286_CR19","doi-asserted-by":"publisher","first-page":"678","DOI":"10.3171\/2011.7.SPINE1152","volume":"15","author":"P Salunke","year":"2011","unstructured":"Salunke P, Sharma M, Sodhi HB, Mukherjee KK, Khandelwal NK (2011) Congenital atlantoaxial dislocation: a dynamic process and role of facets in irreducibility. J NEUROSURGERY-SPINE 15(6):678\u2013685","journal-title":"J NEUROSURGERY-SPINE"},{"issue":"4","key":"9286_CR20","doi-asserted-by":"publisher","first-page":"630","DOI":"10.1016\/j.jos.2017.02.011","volume":"22","author":"X Huang","year":"2017","unstructured":"Huang X, Yin Q, Wang Z, Xia H (2017) Implantation of the anterior atlantoaxial lateral mass intervertebral cage using the transoral approach. J Orthop Sci 22(4):630\u2013634","journal-title":"J Orthop Sci"},{"issue":"1","key":"9286_CR21","doi-asserted-by":"publisher","first-page":"121","DOI":"10.1186\/s12891-021-03987-2","volume":"22","author":"S Wang","year":"2021","unstructured":"Wang S, Leng H, Tian Y, Xu N, Liu Z (2021) A novel 3D-printed locking cage for anterior atlantoaxial fixation and fusion: case report and in vitro biomechanical evaluation. BMC Musculoskelet Disord 22(1):121","journal-title":"BMC Musculoskelet Disord"},{"key":"9286_CR22","doi-asserted-by":"publisher","first-page":"e120","DOI":"10.1016\/j.wneu.2021.12.012","volume":"159","author":"L Shi","year":"2022","unstructured":"Shi L, Xue D, Wang Y et al (2022) Efficacy of a lateral mass fusion device combined with a three-dimensional-printed model in the treatment of craniovertebral junction abnormalities. World Neurosurg 159:e120\u2013e129","journal-title":"World Neurosurg"},{"issue":"3","key":"9286_CR23","doi-asserted-by":"publisher","first-page":"254","DOI":"10.1093\/ons\/opz122","volume":"18","author":"DD Gonda","year":"2020","unstructured":"Gonda DD, Huang M, Brice\u00f1o V, Lam SK, Luerssen TG, Jea A (2020) Protecting against postoperative dyspnea and dysphagia after occipitocervical fusion. Oper Neurosurg 18(3):254\u2013260","journal-title":"Oper Neurosurg"},{"issue":"5","key":"9286_CR24","doi-asserted-by":"publisher","first-page":"745","DOI":"10.1016\/j.spinee.2019.11.013","volume":"20","author":"LN Wang","year":"2020","unstructured":"Wang LN, Hu BW, Song YM et al (2020) Predictive abilities of O-C2a and O-EAa for the development of postoperative dysphagia in patients undergoing occipitocervical fusion. Spine J 20(5):745\u2013753","journal-title":"Spine J"},{"issue":"23","key":"9286_CR25","doi-asserted-by":"publisher","first-page":"2064","DOI":"10.1097\/BRS.0b013e3181ce1758","volume":"35","author":"L Chang-Wei","year":"2010","unstructured":"Chang-Wei L, Wei L, Zhen-Sheng M, Yan-Wu L, Long B, Nan Z (2010) Posterior rotating rod reduction strategy for irreducible atlantoaxial subluxations with congenital odontoid aplasia. Spine 35(23):2064\u20132070","journal-title":"Spine"},{"issue":"4","key":"9286_CR26","doi-asserted-by":"publisher","first-page":"513","DOI":"10.3109\/02688697.2015.1019421","volume":"29","author":"P Salunke","year":"2015","unstructured":"Salunke P, Sahoo SK, Savardekar A, Ghuman M, Khandelwal NK (2015) Factors influencing feasibility of direct posterior reduction in irreducible traumatic atlantoaxial dislocation secondary to isolated odontoid fracture. Br J Neurosurg 29(4):513\u2013519","journal-title":"Br J Neurosurg"},{"issue":"4","key":"9286_CR27","doi-asserted-by":"publisher","first-page":"365","DOI":"10.1097\/BRS.0b013e3181976aa9","volume":"34","author":"AE Dmitriev","year":"2009","unstructured":"Dmitriev AE, Lehman RA Jr, Helgeson MD, Sasso RC, Kuhns C, Riew DK (2009) Acute and long-term stability of atlantoaxial fixation methods: a biomechanical comparison of pars, pedicle, and intralaminar fixation in an intact and odontoid fracture model. Spine 34(4):365\u2013370","journal-title":"Spine"},{"issue":"15","key":"9286_CR28","doi-asserted-by":"publisher","first-page":"1703","DOI":"10.1097\/00007632-199808010-00018","volume":"23","author":"BY Jun","year":"1998","unstructured":"Jun BY (1998) Anatomic study for ideal and safe posterior C1-C2 transarticular screw fixation. Spine 23(15):1703\u20131707","journal-title":"Spine"}],"container-title":["European Spine Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00586-025-09286-x.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s00586-025-09286-x","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s00586-025-09286-x.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T10:51:18Z","timestamp":1777632678000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s00586-025-09286-x"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,8,23]]},"references-count":28,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2026,4]]}},"alternative-id":["9286"],"URL":"https:\/\/doi.org\/10.1007\/s00586-025-09286-x","relation":{"has-preprint":[{"id-type":"doi","id":"10.21203\/rs.3.rs-7039811\/v1","asserted-by":"object"}]},"ISSN":["0940-6719","1432-0932"],"issn-type":[{"value":"0940-6719","type":"print"},{"value":"1432-0932","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,8,23]]},"assertion":[{"value":"3 July 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"8 August 2025","order":2,"name":"revised","label":"Revised","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"12 August 2025","order":3,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"23 August 2025","order":4,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The authors declare no competing interests.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}},{"value":"All subjects gave consent to publish their data.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"All procedures performed in studies involving human participants were in accordance with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The experimental protocol was approved by the local Hospital Institutional Review Board, and all subjects gave informed consent.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval"}}]}}