{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T05:18:53Z","timestamp":1779340733918,"version":"3.51.4"},"reference-count":33,"publisher":"Public Library of Science (PLoS)","issue":"10","license":[{"start":{"date-parts":[[2023,10,12]],"date-time":"2023-10-12T00:00:00Z","timestamp":1697068800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Introduction<\/jats:title>\n<jats:p>Previous studies demonstrated a release of toxic metals, e.g. nickel and chromium, from stainless steel bars used for minimally invasive repair of pectus excavatum (MIRPE). In the present study, we investigated the impact of titanium nitride coating on the metal release and exposure of MIRPE patients.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Material and methods<\/jats:title>\n<jats:p>We analyzed the courses of nickel and chromium levels in blood, urine and local tissue in patients undergoing MIRPE with a titanium nitride coated pectus bar between 03\/2017 and 10\/2018. Sample collection was scheduled prior to MIRPE, at defined postoperative time points and at bar removal. Additionally, we evaluated irritative symptoms. Results were compared to a control group who received uncoated stainless steel bars in a previous time period (03\/2015\u201302\/2017).<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Results<\/jats:title>\n<jats:p>12 patients received coated pectus bars (mean age 15.7 years). The control group included 28 patients. After implantation of a titanium nitride coated bar, significant increase in systemic nickel and chromium levels after one, two and three years was noted. In an interim analysis one year after MIRPE, we observed patients with coated bars to have significantly elevated trace metal values compared to the control group. This elevation persisted throughout the observation period. Tissue metal values were also significantly increased. Irritative symptoms occurred significantly more often in study patients compared to controls (50.0% vs. 14.3%).<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>Coating of pectus bars with titanium nitride failed to reduce metal contamination after MIRPE. Instead, it resulted in a significant increase of trace metal levels after MIRPE, compared to patients with stainless steel bars, which may be explained by wear of the coating and inter-component mobilization processes.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0292616","type":"journal-article","created":{"date-parts":[[2023,10,12]],"date-time":"2023-10-12T17:35:07Z","timestamp":1697132107000},"page":"e0292616","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":3,"title":["Titanium nitride coating of pectus bar increases metal contamination after minimally-invasive repair of pectus excavatum"],"prefix":"10.1371","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2289-5330","authenticated-orcid":true,"given":"Caroline","family":"Fortmann","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8226-9227","authenticated-orcid":true,"given":"Thomas","family":"G\u00f6en","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Soeren","family":"Wiesner","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jan","family":"Hegermann","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rim","family":"Kiblawi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2471-8530","authenticated-orcid":true,"given":"Martha","family":"Dohna","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Benno M.","family":"Ure","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3702-356X","authenticated-orcid":true,"given":"Diane Miriam","family":"Renz","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Claus","family":"Petersen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joachim F.","family":"Kuebler","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2023,10,12]]},"reference":[{"issue":"1","key":"pone.0292616.ref001","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1016\/j.jpedsurg.2006.09.056","article-title":"When it is not an infection: metal allergy after the Nuss procedure for repair of pectus excavatum","volume":"42","author":"GD Rushing","year":"2007","journal-title":"J Pediatr Surg"},{"issue":"3","key":"pone.0292616.ref002","doi-asserted-by":"crossref","first-page":"451","DOI":"10.1016\/j.jpedsurg.2013.07.014","article-title":"High rates of metal allergy amongst Nuss procedure patients dictate broader pre-operative testing","volume":"49","author":"B Shah","year":"2014","journal-title":"J Pediatr Surg"},{"issue":"2","key":"pone.0292616.ref003","doi-asserted-by":"crossref","first-page":"260","DOI":"10.1016\/j.jpedsurg.2017.11.021","article-title":"Selective versus routine patch metal allergy testing to select bar material for the Nuss procedure in 932 patients over 10 years","volume":"53","author":"RJ Obermeyer","year":"2018","journal-title":"J Pediatr Surg"},{"key":"pone.0292616.ref004","article-title":"Recent Modifications of the Nuss Procedure. 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