{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,27]],"date-time":"2026-05-27T20:00:37Z","timestamp":1779912037044,"version":"3.53.1"},"reference-count":40,"publisher":"Wiley","issue":"5","license":[{"start":{"date-parts":[[2021,1,15]],"date-time":"2021-01-15T00:00:00Z","timestamp":1610668800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"},{"start":{"date-parts":[[2021,1,15]],"date-time":"2021-01-15T00:00:00Z","timestamp":1610668800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.springer.com\/tdm"},{"start":{"date-parts":[[2021,1,15]],"date-time":"2021-01-15T00:00:00Z","timestamp":1610668800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.springer.com\/tdm"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Knee surg. sports traumatol. arthrosc."],"published-print":{"date-parts":[[2021,5]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec><jats:title>Purpose<\/jats:title><jats:p>To investigate the prevalence of magnetic resonance imaging (MRI) findings and define prognostic factors of the return\u2010to\u2010play time in young athletes with groin pain.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>A total of 1091 consecutive athletes were retrospectively screened; 651 athletes, aged 16\u201340 years, with pain in the groin regions were assessed using MRI. Of these athletes, 356 were included for analysing the time to return\u2010to\u2010play. Univariate and multiple linear regression analyses were used to determine the associations between the time to return\u2010to\u2010play (primary outcome variable) and the following variables: age, sex, body mass index, type of sports, Hip Sports Activity Scale, clear trauma history, and 12\u00a0MRI findings.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>Four MRI findings, including cleft sign, pubic bone marrow oedema of both the superior and inferior ramus, and central disc protrusion of the pubic symphysis, appeared together in more than 44% of the cases. The median time to return\u2010to\u2010play was 24.7 weeks for athletes with a cleft sign on MRI, which was significantly longer than the 11.9 weeks for athletes without the sign. The median time to return\u2010to\u2010play was 20.8 weeks for athletes with BMI\u2009&gt;\u200924, which was significantly longer than the 13.6 weeks for athletes with BMI \u2266 24.<\/jats:p><jats:p>In multiple linear regression analysis of 356 athletes, in whom hip\u2010related groin pain was excluded, and who were followed\u2010up until the return\u2010to\u2010play, the body mass index and cleft sign were the independent factors associated with a delayed return\u2010to\u2010play. In contrast, iliopsoas muscle strain and other muscle injuries were associated with a shorter return\u2010to\u2010play.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>Multiple MRI findings were present in almost half of all cases. Body mass index and the cleft sign were independently associated with a delayed return\u2010to\u2010play time in young athletes suffering from groin pain.<\/jats:p><\/jats:sec><jats:sec><jats:title>Level of evidence<\/jats:title><jats:p>III.<\/jats:p><\/jats:sec>","DOI":"10.1007\/s00167-020-06410-w","type":"journal-article","created":{"date-parts":[[2021,1,15]],"date-time":"2021-01-15T15:44:02Z","timestamp":1610725442000},"page":"1474-1482","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["The cleft sign may be an independent factor of magnetic resonance imaging findings associated with a delayed return\u2010to\u2010play time in athletes with groin pain"],"prefix":"10.1002","volume":"29","author":[{"given":"Masayoshi","family":"Saito","sequence":"first","affiliation":[{"name":"<!--<label>1<\/label>--> Department of Orthopaedic Surgery St. Luke\u2019s International Hospital 9\u20101 Akashicho, Chuo\u2010ku 104\u20108560 Tokyo Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1471-7208","authenticated-orcid":false,"given":"Sadao","family":"Niga","sequence":"additional","affiliation":[{"name":"<!--<label>2<\/label>--> JIN Orthopaedic &amp; Sports Clinic 3\u201010\u20107 Suzuya, Chuo\u2010ku 338\u20100013 Saitama Saitama Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tadahiro","family":"Nihei","sequence":"additional","affiliation":[{"name":"<!--<label>2<\/label>--> JIN Orthopaedic &amp; Sports Clinic 3\u201010\u20107 Suzuya, Chuo\u2010ku 338\u20100013 Saitama Saitama Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mari","family":"Uomizu","sequence":"additional","affiliation":[{"name":"<!--<label>3<\/label>--> Department of Orthopaedic Surgery Nerima General Hospital 1\u201024\u20101 Asahigaoka, Nerima\u2010ku 176\u20108530 Tokyo Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuji","family":"Ikezawa","sequence":"additional","affiliation":[{"name":"<!--<label>2<\/label>--> JIN Orthopaedic &amp; Sports Clinic 3\u201010\u20107 Suzuya, Chuo\u2010ku 338\u20100013 Saitama Saitama Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sachiyuki","family":"Tsukada","sequence":"additional","affiliation":[{"name":"<!--<label>4<\/label>--> Department of Orthopaedic Surgery Hokusuikai Kinen Hospital 3\u20102\u20101 Higashihara 310\u20100035 Mito Ibaraki 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