Question 1803
{"accessible":true,"alternatives":[{"id":8957,"text":"aneurysmal bone cyst"},{"id":8960,"text":"giant cell tumor"},{"id":8958,"text":"intraosseous lipoma"},{"id":8961,"text":"pseudotumor"},{"id":8959,"text":"unicameral bone cyst"}],"archived":false,"correctAlternativeId":8958,"explanation":"\u003cp\u003eThere is a well-defined lucent lesion with a narrow transition\u0026nbsp;zone of the anteroinferior aspect of the calcaneum with a central calcification \"\u003ca href=\"/articles/cockade-sign-intraosseous-lipoma\"\u003ecockade sign\u003c/a\u003e\". This\u0026nbsp;\"cockade sign\"\u0026nbsp;describes the classic appearance of a calcaneal\u0026nbsp;\u003ca href=\"https://radiopaedia.org/articles/intraosseous-lipoma?lang=gb\"\u003eintraosseous lipoma\u003c/a\u003e.\u003c/p\u003e\u003cp\u003eOn simple radiographs, the main differential diagnosis includes:\u003c/p\u003e\u003cul\u003e\u003cli\u003epseudotumor of the calcaneus\u003c/li\u003e\u003cli\u003eaneurysmal bone cyst\u003c/li\u003e\u003cli\u003eunicameral\u0026nbsp;bone cyst\u0026nbsp;\u003c/li\u003e\u003cli\u003egiant cell tumor\u003c/li\u003e\u003c/ul\u003e\u003cp\u003eOn CT/MRI: the CT attenuation and MRI signal\u0026nbsp;characteristics of the lesion\u0026nbsp;narrowed down\u0026nbsp;the\u0026nbsp;differential diagnosis to fat-containing lesions of the bone.\u0026nbsp;\u003c/p\u003e\u003cp\u003eImage credit:\u0026nbsp;Dr Mohammad Taghi Niknejad, Radiopaedia.org, rID: 20493\u003c/p\u003e","id":1803,"imageUrl":"https://prod-images-static.radiopaedia.org/multiple_choice_questions/290/calcaneal-lipoma-with-cockade-sign-2_big_gallery.jpeg","imageAttribution":null,"imageAttributionCaseInfo":null,"firstQuestionPath":"/questions/1803","nextQuestionPath":null,"relatedArticles":[{"id":7189,"title":"Simple bone cyst","link":"/articles/simple-bone-cyst?lang=us"},{"id":13670,"title":"Intraosseous lipoma","link":"/articles/intraosseous-lipoma?lang=us"},{"id":1385,"title":"Giant cell tumor of bone","link":"/articles/giant-cell-tumour-of-bone?lang=us"},{"id":22033,"title":"Cockade sign (intraosseous lipoma)","link":"/articles/cockade-sign-intraosseous-lipoma?lang=us"},{"id":22322,"title":"Calcaneal lesions (mnemonic)","link":"/articles/calcaneal-lesions-mnemonic?lang=us"}],"alsoUsedIn":[{"id":1430,"kind":"RestrictedPage","title":"Page 1430 (in no courses)","link":"https://radiopaedia.org/admin/restricted_pages/1430"},{"id":1110,"kind":"RestrictedPage","title":"Page 1110 (in no courses)","link":"https://radiopaedia.org/admin/restricted_pages/1110"},{"id":2033,"kind":"Course","title":"X-ray Interpretation: Foot \u0026 Ankle Injuries Peer Review - page 2033","link":"https://radiopaedia.org/courses/x-ray-interpretation-foot-ankle-injuries-peer-review/pages/2033"},{"id":2033,"kind":"Course","title":"X-ray Interpretation: Foot \u0026 Ankle Injuries - page 2033","link":"https://radiopaedia.org/courses/x-ray-interpretation-foot-ankle-injuries/pages/2033"},{"id":2077,"kind":"Course","title":"X-ray Interpretation: Bone Lesions Peer Review - page 2077","link":"https://radiopaedia.org/courses/x-ray-interpretation-bone-lesions-peer-review/pages/2077"},{"id":2077,"kind":"Course","title":"X-ray Interpretation: Bone Lesions - page 2077","link":"https://radiopaedia.org/courses/x-ray-interpretation-bone-lesions/pages/2077"}],"stem":"\u003cp\u003eA 40-year-old man with a history of trauma to the left ankle. What is the most likely diagnosis shown on this lateral radiograph?\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/1803"}],"attemptsPercentages":[{"alternativeId":"8958","percentage":89},{"alternativeId":"8957","percentage":2},{"alternativeId":"8960","percentage":1},{"alternativeId":"8959","percentage":5},{"alternativeId":"8961","percentage":2}],"promptToLogin":false,"questionManager":false,"articleId":"pseudotumor-of-the-calcaneus"}