{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,2,21]],"date-time":"2025-02-21T14:14:43Z","timestamp":1740147283957,"version":"3.37.3"},"reference-count":30,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2024,3,13]],"date-time":"2024-03-13T00:00:00Z","timestamp":1710288000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2024,3,13]],"date-time":"2024-03-13T00:00:00Z","timestamp":1710288000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["J Med Case Reports"],"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Background<\/jats:title>\n                <jats:p>Use of ureteral stents has become an integral part of urological practice. However, it also brought with it many complications. Double J (DJ) stent knotting is a rare stent complication, and only a few cases have been reported in the literature. Although the exact cause is unknown and, in the literature, it is generally thought that knots occur due to traction. In this case report we present for the first time that spontaneous knots can occur due to ureteral peristalsis or ureteral anomalies.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Case presentation<\/jats:title>\n                <jats:p>Two patients (67 and 35 aged-Caucasian person) with ureteral stones who presented to the emergency department with colicky pain and had no previous history of urological surgery. We observed knot formation in the routine urinary system radiographs taken before stent removal in two patients whose ureters were observed to be narrow during endoscopic ureteral stone treatment. The stents were successfully removed using gentle traction under general anesthesia.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>We discussed the cause and solution of spontaneous knot formation. We emphasized the importance of the direct urinary system radiograph taken before DJ stent removal.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s13256-024-04395-5","type":"journal-article","created":{"date-parts":[[2024,3,13]],"date-time":"2024-03-13T01:31:39Z","timestamp":1710293499000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Spontaneous knot formation complication of double J: two\u00a0case reports"],"prefix":"10.1186","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3524-2400","authenticated-orcid":false,"given":"Ahmet Can","family":"Kolu","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6066-0401","authenticated-orcid":false,"given":"Serkan","family":"Akan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2024,3,13]]},"reference":[{"issue":"3","key":"4395_CR1","first-page":"249","volume":"30","author":"AE Groeneveld","year":"1989","unstructured":"Groeneveld AE. 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A copy of the written consent is available for review by the Editor-in-Chief of this journal.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare that they have no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"103"}}