Question 1813
{"accessible":false,"alternatives":[{"id":9006,"text":"arcuate foramen"},{"id":9007,"text":"atlantoaxial assimilation "},{"id":9008,"text":"atlantooccipital assimilation"},{"id":9009,"text":"congenital defect of the posterior arch"},{"id":9010,"text":"epitransverse process"}],"archived":false,"correctAlternativeId":9006,"explanation":"\u003cp\u003e\u003ca title=\"Arcuate foramen\" class=\"internal\" href=\"/articles/arcuate-foramen\"\u003eArcuate foramina\u003c/a\u003e have an incidence of around 8%. \u003ca title=\"Congenital anomalies of posterior arch of C1\" class=\"internal\" href=\"/articles/congenital-anomalies-of-the-posterior-atlas-arch-1\"\u003ePosterior arch defects\u003c/a\u003e are also quite common with an incidence of around 1-3%. \u003ca title=\"Atlanto-occipital assimilation\" class=\"internal\" href=\"/articles/atlanto-occipital-assimilation\"\u003eAtlantooccipital assimilation\u003c/a\u003e and \u003ca title=\"Epitransverse process of the atlas\" class=\"internal\" href=\"/articles/epitransverse-process-of-the-atlas\"\u003eepitransverse processes\u003c/a\u003e are rare. Atlantoaxial assimilation is not even a thing so that’s definitely not the answer!\u003c/p\u003e","id":1813,"imageUrl":null,"imageAttribution":null,"imageAttributionCaseInfo":null,"firstQuestionPath":"/questions/1813","nextQuestionPath":"/articles/arcuate-foramen/questions/1810","relatedArticles":[{"id":28434,"title":"Atlanto-occipital assimilation","link":"/articles/atlanto-occipital-assimilation?lang=us"}],"alsoUsedIn":[{"id":804,"kind":"Course","title":"X-ray Interpretation: Cervical Spine - page 804","link":"https://radiopaedia.org/courses/x-ray-interpretation-cervical-spine/pages/804"},{"id":804,"kind":"Course","title":"Emergency Radiology Course - Melbourne - page 804","link":"https://radiopaedia.org/courses/emergency-radiology-course-melbourne-2022/pages/804"},{"id":804,"kind":"Course","title":"Emergency Radiology Course - Brisbane - page 804","link":"https://radiopaedia.org/courses/emergency-radiology-course-brisbane-2022/pages/804"}],"stem":"\u003cp\u003eWhich of the following is the most common anatomical variation of C1 (atlas)?\u003c/p\u003e","menuLinks":[{"text":"Report problem with question","url":"https://docs.google.com/forms/d/e/1FAIpQLSfO3soWYhOjJ7yErSysyCe5V4A1CqW7WK3rDA7MtAkecMGqNw/viewform?entry.1624461248\u0026entry.553583435=https://radiopaedia.org/questions/1813"}],"attemptsPercentages":[{"alternativeId":"9008","percentage":8},{"alternativeId":"9006","percentage":63},{"alternativeId":"9009","percentage":20},{"alternativeId":"9007","percentage":5},{"alternativeId":"9010","percentage":4}],"promptToLogin":false,"questionManager":false,"articleId":"arcuate-foramen"}