Developmental atlanto-stenosis with Klippel-Feil syndrome showing "snake eye sign" on MRI：Case report and reflection Abstract

Developmental atlanto-stenosis with Klippel-Feil syndrome showing "snake eye sign" on MRI：Case report and reflection Abstract | 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 Case Report Developmental atlanto-stenosis with Klippel-Feil syndrome showing "snake eye sign" on MRI：Case report and reflection Abstract yan liu, NIANHU LI This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3624023/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 A patient with "snake eye" developmental atlanteal stenosis complicated with Klippel-Feil syndrome and cervical spinal cord injury was admitted to our hospital in March 2022. X-ray, CT and MRI examinations were performed. It was found that the patient had atlanto-spinal stenosis, C2-C6 fusion deformity, cervical instability, thoracolumbar disc herniation, and L5-S1 fusion deformity combined with cervical spinal cord signal changes. The patient underwent posterior cervical resection of posterior atlas arch for decompression of vertebral canal + C6/7 total laminectomy for decompression of vertebral canal and posterior lateral bone grafting with C5-T1 nail rod system for internal fixation, which resulted in poor functional recovery. Summarize and reflect on its treatment ideas, and further deepen the understanding of this kind of disease. Developmental atlanto-stenosis Klippel-Feil syndrome Snake eye sign Figures Figure 1 INTRODUCTION A 51-year-old female patient was admitted to the hospital due to "walking instability for 8 years, aggravated for 2 months". She developed weakness of both lower limbs and walking instability without obvious causes 8 years ago, neck pain accompanied by numbness of hands, inflexibility of hands, and poor fine movement 4 years ago, and the above symptoms worsened 2 months ago, with a feeling of stepping on cotton and difficulty urinating and defecating. Physical examination: limited neck movement, neck tenderness, tapping pain, increased muscle tension in both upper limbs. Muscle strength of left triceps humeral, interosseous muscle, extensor thumb long and extensor toe long were all grade IV, bilateral iliopsoas muscle strength was grade IV, left anterior tibialis muscle strength was grade Ⅲ, right anterior tibialis muscle and extensor toe long muscle strength was grade Ⅱ, right extensor thumb long muscle strength was grade Ⅲ, left radial membrane reflex and biceps reflex (++++), right radial membrane reflex and bicep muscle reflex (+++), Left brachial plexus pull test (+), bilateral Hoffmann sign (+), left Babinski sign (+). Auxiliary examination: No obvious abnormality was found in cardiac and abdominal color ultrasonography. There were no significant abnormalities in the electromyography of the upper limb. Cervical and lumbar MRI showed: 1. Cervical C2-C6 fusion deformity, magnum occipital stenosis, intramedullary degeneration of the medulla oblongata and superior segment, and "snake eye sign" at the atlas and C6/7 level. C6/7 disc bulge and herniation, spinal canal stenosis, C6/7 spinal cord degeneration. 2.L5-S1 vertebral body fusion deformity, abnormal bone behind the vertebral body, sacral canal retraction and curvature. Cervical CTA showed multiple mild stenosis of the internal carotid arteries on both sides, variation of the right vertebral artery, mild stenosis in the V4 segment with calcified plaque, and absence of the left vertebral artery. The patients' JOA score was 6 points according to the standard of spinal cord function assessment with JOA17. Subsequently, the patient underwent posterior atlas arch resection and laminectomy, fusion, and internal fixation. Other adequate treatments as well as adjuvant medications, such as improved microcirculation, dehydration and neuronutritional therapy, are administered postoperatively. Neck pain and light numbness of hands, muscle strength of both lower limbs: bilateral iliopsoas muscle strength is Ⅴ, left anterior tibial muscle strength is Ⅳ, right anterior tibial muscle strength is Ⅲ, left extensor thumb long muscle strength is Ⅴ, right extensor thumb long muscle strength is Ⅳ, right extensor toe muscle strength is Ⅲ. The double upper limb numbness and neck pain were aggravated six months after the operation. The cervical spine reexamination one year after the operation showed that the range of C6/7 spinal cord degeneration was enlarged, but the bulbar and atlas level spinal cord degeneration was improved, and the symptoms returned to the preoperative status, with limited neck movement and difficulty in lifting head.(Fig. 1 ) CASE DESCRIPTION AND REFLECTION The pathogenesis of Klippel-Feil syndrome is mainly related to genes ( 1 ), the failure of cervical grey body segmentation and differentiation, resulting in cervical melascope malformations, most commonly C2-C3 and C5-C6 levels ( 2 ). In addition to cervical melotone deformity, KFS often presents other diseases such as visceral lesions ( 3 ). Short neck, low back hairline and limited neck movement are the KFS triad. Professor Feil divided KFS into three types, of which this case was type III, presenting cervical fusion combined with lumbar fusion. KFS patients are more likely to be combined with acute disc herniation or cervical spondylotic myelopathy than the general population due to the fusion biomechanical changes of cervical deformity and fusion, resulting in stress concentration in the upper and lower intervertebral space of fusion vertebrae and greater mobility compensation ( 2 ). Patients with Klippel-Feil syndrome may be at high risk of developing transient neurological dysfunction after minor trauma ( 4 ). Patients with Klippel-Feil syndrome are different due to different lesion sites, types, and complications, so there are no clinical retrospective studies on cases, and most cases are reported ( 5 ). As in this patient, 5 consecutive cervical vertebrae fusion combined with lumbosacral vertebrae fusion has not been reported in clinical studies and is extremely rare. It is more likely to cause cervical spondylotic myelopathy. Stenosis at the upper cervical level is also less common in cases of spinal stenosis than at the lower cervical level ( 6 ). Most cases of atlanto-spinal stenosis were found to be presented with symptoms of spinal cord compression at the time of visit, and a considerable number of them were presented with atlanto-axial joint instability, dislocation, or severe ossification of the posterior longitudinal ligament ( 7 ). However, atlanto-spinal stenosis can cause compression of the high cervical spinal cord and lead to cervical myelopathy, which should be taken seriously ( 8 ). Previous studies on the measurement of the midsagittal diameter in normal European, American, Japanese and Chinese people used the midsagittal diameter ≤ 26 mm, 30 mm and 26.7 mm as the criteria for the diagnosis of developmental atlanto-stenosis ( 9 ). Atlantal hypoplasia or malformation can lead to a reduction in the effective spinal canal area of the atlantal, which can compress the spinal cord and even cause damage to the medulla oblongata, with mild neurological symptoms of high cervical spondylotic myelopathy, and severe respiratory depression, which can be life-threatening. K.Daniel Riew et al. provided an anatomical definition of atlas stenosis by dissecting 543 cervical vertebrae specimens, and the internal sagittal diameter was less than or equal to 26mm, which could be defined as atlas hypoplasia ( 10 ). Clinically, space available for the cord (SAC) is widely used as an indicator of spinal cord compression ( 9 ). Previous studies have shown that SAC < 12mm can cause spinal cord compression, and other studies have suggested that SAC < 14mm should also be used as the threshold for atlanta-based spinal cord compression ( 11 ). In this study, the median sagittal diameter of the atlas was 16.31mm, SAC was 6.87mm, and the posterior arch of the atlas was hypertrophy with a thickness of 12.79mm. MRI showed signal changes in the spinal cord and medulla oblongata, with obvious stenosis. Decompression of posterior atlas arch is an effective method for the treatment of C1 level spinal stenosis. The surgical options for posterior atlas arch decompression include either posterior atlas arch resection or single door enlarged spinal canal plasty, which cannot be applied to types A, C, and D of the Currarino classification that may lead to spinal cord compression ( 12 ). Surgical indications for posterior arch decompression include: ventral spinal cord compression caused by odontoid hyperplasia, postodontoid pseudotumor, transverse ligament calcification, ossification of posterior longitudinal ligament of odontoid, etc., and dorsal spinal cord compression caused by Chiari malformation of cerebellar subtonsillar hernia and posterior atlantoid arch malformation ( 13 , 14 ). The case in this study was Klippel Feil syndrome, with malformed fusion of the armature odontoid process with the anterior atlas arch and developmental hypertrophy of the posterior arch pressing on the spinal cord, which was consistent with the indication of posterior arch decompression. Internal fixation was not required because atlantoaxial fusion was stable. The patient underwent posterior arch resection, and postoperative MRI showed improved signals of the medulla oblongata and the spinal cord at the atlas level. The most controversial issue in the treatment plan is the management of C6/7 segment. Finally, C6 laminectomy and C5-T1 internal fixation were performed on the patient, but ideal results were not achieved after surgery. MRI showed that the spinal cord signal range increased, the patient had obvious neck pain, aggravated mobility restriction, and numbness in both upper limbs. Now we reflect on this treatment plan. First, the diagnosis of C6/7 level cervical spondylotic myelopathy in the patient has yet to be confirmed, and there is a "snake eye sign" for spinal cord degeneration, which is not characteristic. Snake eye sign, also known as owl eye sign, is due to the damage of the anterior horn cells. The anterior horn of the gray matter is sensitive to ischemia, and the anterior horn of the gray matter of the spinal cord is necrotic, and the dot signal with enhanced symmetry on imaging is similar to the snake eye, so it is called the snake eye sign ( 15 ). Autopsy histological examination of 9 patients with "snake eye sign" by MIZUNO J's team from Japan revealed small cystic necrosis in the central gray matter, spongiform degeneration around the necrotic tissue, fibrinoid degeneration of pericystic venules, narrowing of lumen, and significant loss of neurons in the flattened anterior horn of the spinal cord. It has been reported that cervical spondylotic myelopathy, amyotrophic lateral sclerosis, anterior spinal artery syndrome, Hirayama disease, poliomyelitis, flail arm syndrome and other diseases have "snake eye sign" on spinal MRI ( 16 ). The left vertebral artery was absent, the right vertebral artery was deviated, and the V4 segment was slightly narrowed with calcified plaque. No further examination of intramedullary blood vessels was performed before surgery, which could not rule out the occurrence of "snake eye sign" caused by vascular diseases. The significance of decompression in the treatment of C6/7 segment spinal cord degeneration was not clear. The enlarged scope of postoperative MRI spinal cord degeneration may also be caused by the further aggravation of spinal cord ischemia caused by the destruction of small blood vessels during the operation. This has not been confirmed. Thirdly, the choice of surgical methods for patients with C6/7 level decompression is also a controversial point. Klippel-Feil syndrome patients due to congenital dysplasia, multi-level vertebral fusion, decreased range of motion, so the surgical treatment should minimize the impact on their range of motion and adopt non-fusion techniques. It has been reported that patients with Klippel-Feil syndrome combined with cervical spondylosis were treated with artificial disc replacement and achieved good results ( 17 ). However, in this case, the patient had too many fusion segments and the cervical lordosis was angular. After artificial disc replacement, the biomechanical stability was unstable, and the stress concentration could easily lead to the protrusion of the replaced disc and compression of the anterior structure. The patient underwent the surgical program of internal fixation with nail rod system and posterolateral bone graft fusion. Due to the abnormal structure of the patient and the failure of the surgeon to maintain the cervical lordosis Angle, the patient had difficulty in raising his head and his eyes were difficult to look straight ahead. After posterior internal fixation, the patient had almost no cervical motion and obvious pain, indicating that this surgical protocol is not suitable for patients with Klippel Feil syndrome with multi-level fusion. Laminoplasty may be a better option to maintain the patient's range of motion if decompression is required. Decompression of the spinal degenerative segment to preserve the patient's last cervical segment of motion may have better results after surgery. Other surgical methods for the treatment of KFS complicated with cervical spondylotic myelopathy, such as ACDF and PCED, have also been reported clinically. However, due to the extremely special condition of this patient, the stability of anterior fusion surgery with many fusion segments is difficult to guarantee and is not applicable. Inadequate preoperative examination and unreasonable treatment plan design led to the failure of this patient's operation, and the patient lost trust in the later stage, resulting in the failure of further follow-up treatment. It is hoped that this case can bring some enlightenment and alarm to the subsequent treatment of such diseases. CONCLUSIONS For patients with "snake eye sign" on MRI, relevant examination should be improved, other diseases should be excluded, and diagnosis should be made clear before further treatment. For patients with developmental atlanto-stenosis complicated with Klippel-Feil syndrome, it is difficult to achieve a unified and standardized surgical treatment plan. Patients with Klippel-Feil syndrome should minimize the impact of surgery on range of motion while addressing the patient's problems. Declarations Ethics approval Not applicable. Consent Full written informed consent from the patient was obtained for publishing this article and images. Availability of Data and Materials The datasets used and analyzed during the present study are not publicly available due to ethical reason but are available from the corresponding author upon reasonable request. Consent for Publication Informed consents were obtained from the patient for for publication of their clinical data and accompanying images. Funding This work was supported by the 2021 Science and Technology Research Project approved by Shandong Geriatrics Society (No. : LKJGG2021Z009). Conflicts of Interest The authors declare that there is no conflict of interests regarding the publication of this paper. Authors ’ contributions Yan Liu : Methodology, Software, Investigation, Writing—original draft Nianhu LI: Conceptualization, Resources, Supervision, Project administration References Guapi Nauñay VH, Martínez Carvajal IA. Síndrome de Klippel-Feil autosómico dominante: Una malformación de segmentación vertebral [Klippel-Feil autosomal dominant syndrome: A malformation of vertebral segmentation][J]. Rev Chil Pediatr. 2019;90(2):194–201. Spanish. 10.32641/rchped.v90i2.779 . PMID: 31095236. -Litrenta J, Bi AS, Dryer JW. Klippel-Feil Syndrome: Pathogenesis, Diagnosis, and Management[J]. J Am Acad Orthop Surg. 2021;29(22):951–960. 10.5435/JAAOS-D-21-00190 . PMID: 34288888. Nouri A, Patel K, Evans H, Saleh M, Kotter MRN, Heary RF, Tessitore E, Fehlings MG, Cheng JS. Demographics, presentation and symptoms of patients with Klippel-Feil syndrome: analysis of a global patient-reported registry[J]. Eur Spine J. 2019;28(10):2257–65. 10.1007/s00586-019-06084-0 . Epub 2019 Jul 30. PMID: 31363914. Vaidyanathan S, Hughes PL, Soni BM, Singh G, Sett P. Klippel-Feil syndrome - the risk of cervical spinal cord injury: a case report[J]. BMC Fam Pract. 2002;3:6. 10.1186/1471-2296-3-6 . PMID: 11985781; PMCID: PMC107839. Ilunga R, Faye M, Diop A, Sodjinou N, Nacoulma V. Cervical Spine Cord Injury Associated with Klippel-Feil Syndrome: A Case Report[J]. Open J Orthop. 2021;11:138–45. 10.4236/ojo.2021.114013 . Tian Y, Zhou FF, Xia T, Zhao YB, Chen X, Pan SF, Zhang L, Zhang FS, Wang SS, Sun Y. [Imaging features of developmental stenosis of atlas with degenerative cervical myelopathy]. Zhonghua Yi Xue Za Zhi. 2022;102(27):2103–2107. Chinese. 10.3760/cma.j.cn112137-20220311-00503 . PMID: 35844112. akeuchiM WN. Upper cervical cord compression due to a C-1 posterior arch in a patient with ossification of the posterior longitudinal ligament and a kyphotic cervical spine in the protruded-head position: case report[J]. J Neurosurg Spine. 2013;19(4):431–5. 10.3171/2013.7.SPINE13229 . JoaquimAF BG. C1 stenosis-an easily missed cause for cervical myelopathy[J]. Neurospine. 2019;16(3):456–61. 10.14245/ns.1938200.100 . WangY AY. Chinese normative values of C1 sagittal canal diameter and definition of C1 hypoplasia[J]. Chin Med J (Engl). 2021;134(11):1362–3. 10.1097/CM9.0000000000001497 . Kelly MP, Oshima Y, Yeom JS, Agarwal R, Bajwa NS, Riew KD. Defining hyoplasia of the atlas: a cadaveric study[J]. Spine (Phila Pa 1976). 2014;39(21):E1243–7. 10.1097/BRS.0000000000000516 . PMID: 25029221; PMCID: PMC4177343. Kawaida H, Sakou T, Morizono Y, et al. Magnetic resonance imaging of upper cervical disorders in rheumatoid arthritis [J]. Spine (Phila Pa 1976). 1989;14(11):1144–8. 10.1097/00007632-198911000-00003 . haoB WYF. Extended to C1, 2 spinal posterior cervical open-door expansion of the angioplasty treatment combined with cervical spinal stenosis[J]. Chin J Orthop. 2016;36(10):598–604. 10.3760/cma.j.issn.0253-2352.2016.10.004 . MenezesAH. Craniocervical developmental anatomy and its implications[J]. Childs Nerv Syst. 2008;24(10):1109–22. 10.1007/s00381-008-0600-1 . ParkJH LE. Postoperative Regression of Retro-odontoid Pseudotumor After Atlantoaxial Posterior Fixation: 11 Years of Experience in Patients With Atlantoaxial Instability[J]. Spine (Phila Pa 1976). 2017;42(23):1763–71. 10.1097/BRS.0000000000002222 . Zhang Z, Wang H. Is the snake-eye MRI sign correlated to anterior spinal artery occlusion on CT angiography in cervical spondylotic myelopathy and amyotrophy? Eur Spine J. 2014;23(7):1541–7. 10.1007/s00586-014-3348-1 . Epub 2014 May 14. PMID: 24823850. Sharma S, Murgai A, Nair PP, Ramesh A. Teaching NeuroImages: snake eyes appearance in MRI in patient with ALS. Neurology. 2013;81(5):e29. 10.1212/WNL.0b013e31829d85ae . PMID: 23897882. Leung CH, Ma WK, Poon WS. Bryan artificial cervical disc arthro-plasty in a patient with Klippel-Feil syndrome[J]. Hong Kong MedJ. 2007;13(5):399–402. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3624023","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":252945377,"identity":"f9769792-9c8a-4899-86db-b8d0aacb0e4a","order_by":0,"name":"yan liu","email":"","orcid":"","institution":"Shandong University of Traditional Chinese Medicine","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"yan","middleName":"","lastName":"liu","suffix":""},{"id":252945379,"identity":"7bbcf53a-9b11-43aa-b13a-f0ca96a603e9","order_by":1,"name":"NIANHU LI","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA2UlEQVRIie3RMQrCMBSA4UAgUzBrClKvECh00c2LvCDERcGxQ4dKxQ4qXqWjoxLoFHHtmB7BTRfRdlVs3Rzyzfl5LwlCjvOHCFumVj5GPsP4ZCGK25Me14WwRAVeRibCmqI98ZECzxIt8wsNvWqFOyyGjBBAdeClREUyIYhlG/ie4K2wwKf1XYpSHvqIm3PeYYoYNlNKaQgSfN6WzAQHwDLXNFzINe6SKOBwHDcJ6pbUjywTVS824WAK2nqXwX6ZVvfk9ZVMn663KPZZtvuevKG/HXccx3E+egJHEknLyeDu0wAAAABJRU5ErkJggg==","orcid":"","institution":"Affiliated Hospital of Shandong University of Traditional Chinese Medicine","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"NIANHU","middleName":"","lastName":"LI","suffix":""}],"badges":[],"createdAt":"2023-11-17 06:14:21","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3624023/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3624023/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":47309497,"identity":"e4fa32d1-cf06-420c-8f5e-c6acb3d08a58","added_by":"auto","created_at":"2023-11-29 16:26:44","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1607065,"visible":true,"origin":"","legend":"\u003cp\u003eA 51-year-old female patient presented with walking instability for 8 years, aggravation for 2 months, neck pain with numbness in both upper limbs for 4 years. DR: Cervical C2-C6 fusion deformity with limited cervical mobility (A, B). CT showed C2-C6 fusion deformity of cervical spine, stenosis of foramen magnum, hypertrophy of posterior atlas arch, and severe hyperplasia of C6/7 bone. L5-S1 vertebral fusion deformity, abnormal bone behind the vertebral body, sacral canal retraction, curvature (C-F). Cervical CTA showed multiple mild stenosis of internal carotid arteries on both sides, right vertebral artery variation, V4 segment mild stenosis with calcified plaque, and absence of left vertebral artery (G). MRI showed degeneration of the medulla oblongata and the upper medulla oblongata, and \"snake eye sign\" at the atlas and C6/7 level. C6/7 disc bulge and herniation, spinal canal stenosis, C6/7 spinal cord degeneration (H-K). Two days after surgery, DR And CT showed that the posterior atlas arch was removed, and C6/7 segment decompression and internal fixation were performed. The patient's cervical lordosis Angle disappeared and it was difficult to see head-up (L-O). Three months after surgery, DR And CT showed that the internal fixation was stable without broken nails or rods, and the physiological curvature of the patient's cervical spine was further straightened (P, Q). MRI at 8 months after surgery showed that spinal signals were improved at the atlas and medulla oblongata levels, and the range of spinal degeneration increased at the C6/7 level (R, S). Two MRI comparisons showed that there was no significant signal change in the spinal cord before operation at the level of endplate below C6, and the spinal cord was degenerated after operation with \"snake eye sign\" (T, U).\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-3624023/v1/6e9d0a995e72ba343a920222.png"},{"id":48891445,"identity":"69c9356d-53a6-40a2-b125-24124b827522","added_by":"auto","created_at":"2023-12-28 07:22:35","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":683666,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3624023/v1/46243854-589a-4d3d-a351-f67cd672a2ea.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Developmental atlanto-stenosis with Klippel-Feil syndrome showing \"snake eye sign\" on MRI：Case report and reflection Abstract","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eA 51-year-old female patient was admitted to the hospital due to \"walking instability for 8 years, aggravated for 2 months\". She developed weakness of both lower limbs and walking instability without obvious causes 8 years ago, neck pain accompanied by numbness of hands, inflexibility of hands, and poor fine movement 4 years ago, and the above symptoms worsened 2 months ago, with a feeling of stepping on cotton and difficulty urinating and defecating. Physical examination: limited neck movement, neck tenderness, tapping pain, increased muscle tension in both upper limbs. Muscle strength of left triceps humeral, interosseous muscle, extensor thumb long and extensor toe long were all grade IV, bilateral iliopsoas muscle strength was grade IV, left anterior tibialis muscle strength was grade Ⅲ, right anterior tibialis muscle and extensor toe long muscle strength was grade Ⅱ, right extensor thumb long muscle strength was grade Ⅲ, left radial membrane reflex and biceps reflex (++++), right radial membrane reflex and bicep muscle reflex (+++), Left brachial plexus pull test (+), bilateral Hoffmann sign (+), left Babinski sign (+). Auxiliary examination: No obvious abnormality was found in cardiac and abdominal color ultrasonography. There were no significant abnormalities in the electromyography of the upper limb. Cervical and lumbar MRI showed: 1. Cervical C2-C6 fusion deformity, magnum occipital stenosis, intramedullary degeneration of the medulla oblongata and superior segment, and \"snake eye sign\" at the atlas and C6/7 level. C6/7 disc bulge and herniation, spinal canal stenosis, C6/7 spinal cord degeneration. 2.L5-S1 vertebral body fusion deformity, abnormal bone behind the vertebral body, sacral canal retraction and curvature. Cervical CTA showed multiple mild stenosis of the internal carotid arteries on both sides, variation of the right vertebral artery, mild stenosis in the V4 segment with calcified plaque, and absence of the left vertebral artery. The patients' JOA score was 6 points according to the standard of spinal cord function assessment with JOA17. Subsequently, the patient underwent posterior atlas arch resection and laminectomy, fusion, and internal fixation. Other adequate treatments as well as adjuvant medications, such as improved microcirculation, dehydration and neuronutritional therapy, are administered postoperatively. Neck pain and light numbness of hands, muscle strength of both lower limbs: bilateral iliopsoas muscle strength is Ⅴ, left anterior tibial muscle strength is Ⅳ, right anterior tibial muscle strength is Ⅲ, left extensor thumb long muscle strength is Ⅴ, right extensor thumb long muscle strength is Ⅳ, right extensor toe muscle strength is Ⅲ. The double upper limb numbness and neck pain were aggravated six months after the operation. The cervical spine reexamination one year after the operation showed that the range of C6/7 spinal cord degeneration was enlarged, but the bulbar and atlas level spinal cord degeneration was improved, and the symptoms returned to the preoperative status, with limited neck movement and difficulty in lifting head.(Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e)\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"CASE DESCRIPTION AND REFLECTION","content":"\u003cp\u003eThe pathogenesis of Klippel-Feil syndrome is mainly related to genes (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e), the failure of cervical grey body segmentation and differentiation, resulting in cervical melascope malformations, most commonly C2-C3 and C5-C6 levels (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). In addition to cervical melotone deformity, KFS often presents other diseases such as visceral lesions (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Short neck, low back hairline and limited neck movement are the KFS triad. Professor Feil divided KFS into three types, of which this case was type III, presenting cervical fusion combined with lumbar fusion. KFS patients are more likely to be combined with acute disc herniation or cervical spondylotic myelopathy than the general population due to the fusion biomechanical changes of cervical deformity and fusion, resulting in stress concentration in the upper and lower intervertebral space of fusion vertebrae and greater mobility compensation (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). Patients with Klippel-Feil syndrome may be at high risk of developing transient neurological dysfunction after minor trauma (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). Patients with Klippel-Feil syndrome are different due to different lesion sites, types, and complications, so there are no clinical retrospective studies on cases, and most cases are reported (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). As in this patient, 5 consecutive cervical vertebrae fusion combined with lumbosacral vertebrae fusion has not been reported in clinical studies and is extremely rare. It is more likely to cause cervical spondylotic myelopathy.\u003c/p\u003e \u003cp\u003eStenosis at the upper cervical level is also less common in cases of spinal stenosis than at the lower cervical level (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). Most cases of atlanto-spinal stenosis were found to be presented with symptoms of spinal cord compression at the time of visit, and a considerable number of them were presented with atlanto-axial joint instability, dislocation, or severe ossification of the posterior longitudinal ligament (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). However, atlanto-spinal stenosis can cause compression of the high cervical spinal cord and lead to cervical myelopathy, which should be taken seriously (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). Previous studies on the measurement of the midsagittal diameter in normal European, American, Japanese and Chinese people used the midsagittal diameter\u0026thinsp;\u0026le;\u0026thinsp;26 mm, 30 mm and 26.7 mm as the criteria for the diagnosis of developmental atlanto-stenosis (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Atlantal hypoplasia or malformation can lead to a reduction in the effective spinal canal area of the atlantal, which can compress the spinal cord and even cause damage to the medulla oblongata, with mild neurological symptoms of high cervical spondylotic myelopathy, and severe respiratory depression, which can be life-threatening. K.Daniel Riew et al. provided an anatomical definition of atlas stenosis by dissecting 543 cervical vertebrae specimens, and the internal sagittal diameter was less than or equal to 26mm, which could be defined as atlas hypoplasia (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). Clinically, space available for the cord (SAC) is widely used as an indicator of spinal cord compression (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Previous studies have shown that SAC\u0026thinsp;\u0026lt;\u0026thinsp;12mm can cause spinal cord compression, and other studies have suggested that SAC\u0026thinsp;\u0026lt;\u0026thinsp;14mm should also be used as the threshold for atlanta-based spinal cord compression (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). In this study, the median sagittal diameter of the atlas was 16.31mm, SAC was 6.87mm, and the posterior arch of the atlas was hypertrophy with a thickness of 12.79mm. MRI showed signal changes in the spinal cord and medulla oblongata, with obvious stenosis. Decompression of posterior atlas arch is an effective method for the treatment of C1 level spinal stenosis. The surgical options for posterior atlas arch decompression include either posterior atlas arch resection or single door enlarged spinal canal plasty, which cannot be applied to types A, C, and D of the Currarino classification that may lead to spinal cord compression (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). Surgical indications for posterior arch decompression include: ventral spinal cord compression caused by odontoid hyperplasia, postodontoid pseudotumor, transverse ligament calcification, ossification of posterior longitudinal ligament of odontoid, etc., and dorsal spinal cord compression caused by Chiari malformation of cerebellar subtonsillar hernia and posterior atlantoid arch malformation (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). The case in this study was Klippel Feil syndrome, with malformed fusion of the armature odontoid process with the anterior atlas arch and developmental hypertrophy of the posterior arch pressing on the spinal cord, which was consistent with the indication of posterior arch decompression. Internal fixation was not required because atlantoaxial fusion was stable. The patient underwent posterior arch resection, and postoperative MRI showed improved signals of the medulla oblongata and the spinal cord at the atlas level.\u003c/p\u003e \u003cp\u003eThe most controversial issue in the treatment plan is the management of C6/7 segment. Finally, C6 laminectomy and C5-T1 internal fixation were performed on the patient, but ideal results were not achieved after surgery. MRI showed that the spinal cord signal range increased, the patient had obvious neck pain, aggravated mobility restriction, and numbness in both upper limbs. Now we reflect on this treatment plan. First, the diagnosis of C6/7 level cervical spondylotic myelopathy in the patient has yet to be confirmed, and there is a \"snake eye sign\" for spinal cord degeneration, which is not characteristic. Snake eye sign, also known as owl eye sign, is due to the damage of the anterior horn cells. The anterior horn of the gray matter is sensitive to ischemia, and the anterior horn of the gray matter of the spinal cord is necrotic, and the dot signal with enhanced symmetry on imaging is similar to the snake eye, so it is called the snake eye sign (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e). Autopsy histological examination of 9 patients with \"snake eye sign\" by MIZUNO J's team from Japan revealed small cystic necrosis in the central gray matter, spongiform degeneration around the necrotic tissue, fibrinoid degeneration of pericystic venules, narrowing of lumen, and significant loss of neurons in the flattened anterior horn of the spinal cord. It has been reported that cervical spondylotic myelopathy, amyotrophic lateral sclerosis, anterior spinal artery syndrome, Hirayama disease, poliomyelitis, flail arm syndrome and other diseases have \"snake eye sign\" on spinal MRI (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e). The left vertebral artery was absent, the right vertebral artery was deviated, and the V4 segment was slightly narrowed with calcified plaque. No further examination of intramedullary blood vessels was performed before surgery, which could not rule out the occurrence of \"snake eye sign\" caused by vascular diseases. The significance of decompression in the treatment of C6/7 segment spinal cord degeneration was not clear. The enlarged scope of postoperative MRI spinal cord degeneration may also be caused by the further aggravation of spinal cord ischemia caused by the destruction of small blood vessels during the operation. This has not been confirmed. Thirdly, the choice of surgical methods for patients with C6/7 level decompression is also a controversial point. Klippel-Feil syndrome patients due to congenital dysplasia, multi-level vertebral fusion, decreased range of motion, so the surgical treatment should minimize the impact on their range of motion and adopt non-fusion techniques. It has been reported that patients with Klippel-Feil syndrome combined with cervical spondylosis were treated with artificial disc replacement and achieved good results (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e). However, in this case, the patient had too many fusion segments and the cervical lordosis was angular. After artificial disc replacement, the biomechanical stability was unstable, and the stress concentration could easily lead to the protrusion of the replaced disc and compression of the anterior structure. The patient underwent the surgical program of internal fixation with nail rod system and posterolateral bone graft fusion. Due to the abnormal structure of the patient and the failure of the surgeon to maintain the cervical lordosis Angle, the patient had difficulty in raising his head and his eyes were difficult to look straight ahead. After posterior internal fixation, the patient had almost no cervical motion and obvious pain, indicating that this surgical protocol is not suitable for patients with Klippel Feil syndrome with multi-level fusion. Laminoplasty may be a better option to maintain the patient's range of motion if decompression is required. Decompression of the spinal degenerative segment to preserve the patient's last cervical segment of motion may have better results after surgery. Other surgical methods for the treatment of KFS complicated with cervical spondylotic myelopathy, such as ACDF and PCED, have also been reported clinically. However, due to the extremely special condition of this patient, the stability of anterior fusion surgery with many fusion segments is difficult to guarantee and is not applicable.\u003c/p\u003e \u003cp\u003eInadequate preoperative examination and unreasonable treatment plan design led to the failure of this patient's operation, and the patient lost trust in the later stage, resulting in the failure of further follow-up treatment. It is hoped that this case can bring some enlightenment and alarm to the subsequent treatment of such diseases.\u003c/p\u003e"},{"header":"CONCLUSIONS","content":"\u003cp\u003eFor patients with \"snake eye sign\" on MRI, relevant examination should be improved, other diseases should be excluded, and diagnosis should be made clear before further treatment. For patients with developmental atlanto-stenosis complicated with Klippel-Feil syndrome, it is difficult to achieve a unified and standardized surgical treatment plan. Patients with Klippel-Feil syndrome should minimize the impact of surgery on range of motion while addressing the patient's problems.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFull written informed consent from the patient was obtained for publishing this article and images.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of Data and Materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and analyzed during the present study are not publicly available due to ethical reason but are available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for Publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInformed consents were obtained from the patient for for publication of their clinical data and accompanying images.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by the 2021 Science and Technology Research Project approved by Shandong Geriatrics Society (No. : LKJGG2021Z009).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of Interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that there is no conflict of interests regarding the publication of this paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u003c/strong\u003e\u003cstrong\u003e\u0026rsquo;\u003c/strong\u003e\u003cstrong\u003econtributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eYan Liu : Methodology, Software, Investigation, Writing\u0026mdash;original draft\u003c/p\u003e\n\u003cp\u003eNianhu LI: Conceptualization, Resources, Supervision, Project administration\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eGuapi Nau\u0026ntilde;ay VH, Mart\u0026iacute;nez Carvajal IA. S\u0026iacute;ndrome de Klippel-Feil autos\u0026oacute;mico dominante: Una malformaci\u0026oacute;n de segmentaci\u0026oacute;n vertebral [Klippel-Feil autosomal dominant syndrome: A malformation of vertebral segmentation][J]. Rev Chil Pediatr. 2019;90(2):194\u0026ndash;201. Spanish. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.32641/rchped.v90i2.779\u003c/span\u003e\u003cspan address=\"10.32641/rchped.v90i2.779\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 31095236.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003e-Litrenta J, Bi AS, Dryer JW. Klippel-Feil Syndrome: Pathogenesis, Diagnosis, and Management[J]. J Am Acad Orthop Surg. 2021;29(22):951\u0026ndash;960. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.5435/JAAOS-D-21-00190\u003c/span\u003e\u003cspan address=\"10.5435/JAAOS-D-21-00190\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 34288888.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNouri A, Patel K, Evans H, Saleh M, Kotter MRN, Heary RF, Tessitore E, Fehlings MG, Cheng JS. Demographics, presentation and symptoms of patients with Klippel-Feil syndrome: analysis of a global patient-reported registry[J]. Eur Spine J. 2019;28(10):2257\u0026ndash;65. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00586-019-06084-0\u003c/span\u003e\u003cspan address=\"10.1007/s00586-019-06084-0\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. Epub 2019 Jul 30. PMID: 31363914.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVaidyanathan S, Hughes PL, Soni BM, Singh G, Sett P. Klippel-Feil syndrome - the risk of cervical spinal cord injury: a case report[J]. BMC Fam Pract. 2002;3:6. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1186/1471-2296-3-6\u003c/span\u003e\u003cspan address=\"10.1186/1471-2296-3-6\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 11985781; PMCID: PMC107839.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIlunga R, Faye M, Diop A, Sodjinou N, Nacoulma V. Cervical Spine Cord Injury Associated with Klippel-Feil Syndrome: A Case Report[J]. Open J Orthop. 2021;11:138\u0026ndash;45. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.4236/ojo.2021.114013\u003c/span\u003e\u003cspan address=\"10.4236/ojo.2021.114013\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTian Y, Zhou FF, Xia T, Zhao YB, Chen X, Pan SF, Zhang L, Zhang FS, Wang SS, Sun Y. [Imaging features of developmental stenosis of atlas with degenerative cervical myelopathy]. Zhonghua Yi Xue Za Zhi. 2022;102(27):2103\u0026ndash;2107. Chinese. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3760/cma.j.cn112137-20220311-00503\u003c/span\u003e\u003cspan address=\"10.3760/cma.j.cn112137-20220311-00503\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 35844112.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eakeuchiM WN. Upper cervical cord compression due to a C-1 posterior arch in a patient with ossification of the posterior longitudinal ligament and a kyphotic cervical spine in the protruded-head position: case report[J]. J Neurosurg Spine. 2013;19(4):431\u0026ndash;5. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3171/2013.7.SPINE13229\u003c/span\u003e\u003cspan address=\"10.3171/2013.7.SPINE13229\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJoaquimAF BG. C1 stenosis-an easily missed cause for cervical myelopathy[J]. Neurospine. 2019;16(3):456\u0026ndash;61. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.14245/ns.1938200.100\u003c/span\u003e\u003cspan address=\"10.14245/ns.1938200.100\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWangY AY. Chinese normative values of C1 sagittal canal diameter and definition of C1 hypoplasia[J]. Chin Med J (Engl). 2021;134(11):1362\u0026ndash;3. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/CM9.0000000000001497\u003c/span\u003e\u003cspan address=\"10.1097/CM9.0000000000001497\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKelly MP, Oshima Y, Yeom JS, Agarwal R, Bajwa NS, Riew KD. Defining hyoplasia of the atlas: a cadaveric study[J]. Spine (Phila Pa 1976). 2014;39(21):E1243\u0026ndash;7. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/BRS.0000000000000516\u003c/span\u003e\u003cspan address=\"10.1097/BRS.0000000000000516\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 25029221; PMCID: PMC4177343.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKawaida H, Sakou T, Morizono Y, et al. Magnetic resonance imaging of upper cervical disorders in rheumatoid arthritis [J]. Spine (Phila Pa 1976). 1989;14(11):1144\u0026ndash;8. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/00007632-198911000-00003\u003c/span\u003e\u003cspan address=\"10.1097/00007632-198911000-00003\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ehaoB WYF. Extended to C1, 2 spinal posterior cervical open-door expansion of the angioplasty treatment combined with cervical spinal stenosis[J]. Chin J Orthop. 2016;36(10):598\u0026ndash;604. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3760/cma.j.issn.0253-2352.2016.10.004\u003c/span\u003e\u003cspan address=\"10.3760/cma.j.issn.0253-2352.2016.10.004\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMenezesAH. Craniocervical developmental anatomy and its implications[J]. Childs Nerv Syst. 2008;24(10):1109\u0026ndash;22. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00381-008-0600-1\u003c/span\u003e\u003cspan address=\"10.1007/s00381-008-0600-1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eParkJH LE. Postoperative Regression of Retro-odontoid Pseudotumor After Atlantoaxial Posterior Fixation: 11 Years of Experience in Patients With Atlantoaxial Instability[J]. Spine (Phila Pa 1976). 2017;42(23):1763\u0026ndash;71. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/BRS.0000000000002222\u003c/span\u003e\u003cspan address=\"10.1097/BRS.0000000000002222\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZhang Z, Wang H. Is the snake-eye MRI sign correlated to anterior spinal artery occlusion on CT angiography in cervical spondylotic myelopathy and amyotrophy? Eur Spine J. 2014;23(7):1541\u0026ndash;7. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00586-014-3348-1\u003c/span\u003e\u003cspan address=\"10.1007/s00586-014-3348-1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. Epub 2014 May 14. PMID: 24823850.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSharma S, Murgai A, Nair PP, Ramesh A. Teaching NeuroImages: snake eyes appearance in MRI in patient with ALS. Neurology. 2013;81(5):e29. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1212/WNL.0b013e31829d85ae\u003c/span\u003e\u003cspan address=\"10.1212/WNL.0b013e31829d85ae\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 23897882.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLeung CH, Ma WK, Poon WS. Bryan artificial cervical disc arthro-plasty in a patient with Klippel-Feil syndrome[J]. Hong Kong MedJ. 2007;13(5):399\u0026ndash;402.\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":"Developmental atlanto-stenosis, Klippel-Feil syndrome, Snake eye sign","lastPublishedDoi":"10.21203/rs.3.rs-3624023/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3624023/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eA patient with \"snake eye\" developmental atlanteal stenosis complicated with Klippel-Feil syndrome and cervical spinal cord injury was admitted to our hospital in March 2022. X-ray, CT and MRI examinations were performed. It was found that the patient had atlanto-spinal stenosis, C2-C6 fusion deformity, cervical instability, thoracolumbar disc herniation, and L5-S1 fusion deformity combined with cervical spinal cord signal changes. The patient underwent posterior cervical resection of posterior atlas arch for decompression of vertebral canal\u0026thinsp;+\u0026thinsp;C6/7 total laminectomy for decompression of vertebral canal and posterior lateral bone grafting with C5-T1 nail rod system for internal fixation, which resulted in poor functional recovery. Summarize and reflect on its treatment ideas, and further deepen the understanding of this kind of disease.\u003c/p\u003e","manuscriptTitle":"Developmental atlanto-stenosis with Klippel-Feil syndrome showing \"snake eye sign\" on MRI：Case report and reflection Abstract","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-11-29 16:26:39","doi":"10.21203/rs.3.rs-3624023/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":"0fde9a6e-217e-4c04-a816-0c0f00611da0","owner":[],"postedDate":"November 29th, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2023-12-28T07:14:30+00:00","versionOfRecord":[],"versionCreatedAt":"2023-11-29 16:26:39","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3624023","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3624023","identity":"rs-3624023","version":["v1"]},"buildId":"7rjqhiLT3MXkJMwkYKINL","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}