{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,27]],"date-time":"2026-04-27T17:02:00Z","timestamp":1777309320822,"version":"3.51.4"},"reference-count":34,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2021,2,3]],"date-time":"2021-02-03T00:00:00Z","timestamp":1612310400000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2021,2,3]],"date-time":"2021-02-03T00:00:00Z","timestamp":1612310400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Musculoskelet Disord"],"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Retrograde drilling in osteochondrosis dissecans (OCD) is a widely used surgical intervention. A radiation-free electromagnetic navigation system (ENS)-based method was compared with the standard freehand fluoroscopic (SFF) method regarding clinical applicability.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We performed a clinical cohort study at a department of Orthopaedics in a Level 1 children\u2019s hospital with 40 patients (20 SFF and 20 ENS). Retrograde drilling of the talar dome was used in patients with unstable medial OCD (MRI stage 2 according to Hepple\u2019s revised classification; stage 2 according to the International Cartilage Repair Society). The outcome measurements were: (a) Intraoperative fluoroscopy exposure and length of surgery and (b) Postoperative serial follow-up MRIs every 6 months.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      22 female and 18 male patients aged 13.8\u2009\u00b1\u20091.6 years (range: 11\u201317 years) were included. Using the ENS technique, length of surgery was significantly reduced to 20.2\u2009\u00b1\u20096.4 min compared to 36.1\u2009\u00b1\u200911.8 min (p\u2009&lt;\u20090.01) for the SFF technique. The average x-ray radiation time for the SFF technique was 23.5\u2009\u00b1\u200913.5 sec and 1.9\u2009\u00b1\u20091.7 sec for the ENS technique (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.01). Radiation exposure was significantly reduced from 44.6\u2009\u00b1\u200919.7 mSv (SFF technique) to 5.6\u2009\u00b1\u20092.8 mSv (ENS technique) (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.01). Intraoperative perforation of cartilage occurred once in the SFF group. Correct placement of the drilling channel was verified in all patients on follow-up MRI after six months and a timely healing was seen after two years.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>The ENS method provides for a significant reduction in length of surgery and radiation exposure. ENS was without intraoperative cartilage perforation. The clinical and radiological follow-up parameters are comparable for SFF- and ENS-guided retrograde drilling.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Trial registration<\/jats:title>\n                    <jats:p>\n                      WF \u2013 085\/20, 05\/2020 \u201cretrospectively registered\u201d\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"https:\/\/www.aerztekammer-hamburg.org\/ethik_kommission.html\">https:\/\/www.aerztekammer-hamburg.org\/ethik_kommission.html<\/jats:ext-link>\n                      .\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s12891-021-04010-4","type":"journal-article","created":{"date-parts":[[2021,2,3]],"date-time":"2021-02-03T13:04:14Z","timestamp":1612357454000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Electromagnetic navigation reduces radiation exposure for retrograde drilling in osteochondrosis dissecans of the talus"],"prefix":"10.1186","volume":"22","author":[{"given":"Oliver D","family":"Jungesblut","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4952-8271","authenticated-orcid":false,"given":"Josephine","family":"Berger-Groch","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael","family":"Hoffmann","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Malte","family":"Schroeder","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kara L.","family":"Krajewski","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ralf","family":"Stuecker","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Martin","family":"Rupprecht","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2021,2,3]]},"reference":[{"key":"4010_CR1","doi-asserted-by":"publisher","first-page":"150","DOI":"10.1097\/JSA.0000000000000129","volume":"24","author":"M Wu","year":"2016","unstructured":"Wu M, Fallon R, Heyworth BE. 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