{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T11:07:35Z","timestamp":1780484855919,"version":"3.54.1"},"reference-count":43,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,5,28]],"date-time":"2026-05-28T00:00:00Z","timestamp":1779926400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Tourism and Sport of the Slovak Republic"},{"name":"National Sports Centre, Slovakia"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JFMK"],"abstract":"<jats:p>Background: Biological maturity assessment is increasingly discussed in youth sport because chronological age alone does not reflect inter-individual variation in growth and pubertal timing. Ultrasound-based systems such as BAUSport\u2122 provide a radiation-free alternative to radiographic skeletal age assessment. This exploratory cross-sectional study examined skeletal age (SA) in Slovak female volleyball players, track-and-field athletes, and non-athletes using BAUSport\u2122, while acknowledging substantial age differences between groups. Methods: Eighty girls (55 non-athletes, 13 volleyball players, 12 track-and-field athletes; aged 6.85\u201314.41 years) underwent anthropometric measurement and skeletal age (SA) assessment with BAUSport\u2122. Chronological age (CA) was calculated as decimal age from birth date to measurement date. Groups were not age-matched; volleyball players were on average markedly older than the other groups. Skeletal maturity was categorized as early, on-time, or late using a \u00b11.0-year SA\u2013CA threshold. Menarche status was recorded as an indicator of pubertal development. Group differences were evaluated using chi-square or Fisher\u2019s exact tests as appropriate, while differences in SA and SA\u2013CA according to menarche status were assessed using Welch\u2019s t-test. Results: Volleyball players were older (12.90 \u00b1 0.95 years) than non-athletes (10.22 \u00b1 2.40 years) and track-and-field athletes (8.47 \u00b1 1.51 years). They also demonstrated the largest mean SA\u2013CA difference (+1.98 \u00b1 0.73 years). The distribution of maturity categories differed across groups (\u03c72(4) = 14.32, p = 0.006, Cramer\u2019s V = 0.30). Post-menarcheal girls exhibited significantly higher skeletal age and SA\u2013CA values compared to pre-menarcheal girls. However, the substantial age disparity between groups represents a primary confounding factor and limits interpretation of sport-specific effects. Conclusions: This study demonstrates the practical application of BAUSport\u2122 for rapid, radiation-free skeletal age assessment in youth. Differences according to menarche status support the biological relevance of skeletal maturity assessment. However, no valid between-group sport-specific inferences can be made because the groups were not age-matched and puberty is the dominant driver of skeletal maturation. Larger, age-matched studies are required before drawing conclusions regarding sport-specific selection patterns.<\/jats:p>","DOI":"10.3390\/jfmk11020215","type":"journal-article","created":{"date-parts":[[2026,5,29]],"date-time":"2026-05-29T10:06:56Z","timestamp":1780049216000},"page":"215","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Skeletal Age Evaluation with BAUSportTM Ultrasound in Young Slovak Female Athletes and Non-Athletes\u2014A Cross-Sectional Study"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7497-4359","authenticated-orcid":false,"given":"Petra","family":"\u0160v\u00e1bov\u00e1 (nee Uhrov\u00e1)","sequence":"first","affiliation":[{"name":"Department of Anthropology, Faculty of Natural Sciences, Comenius University Bratislava, Ilkovi\u010dova 6, Mlynsk\u00e1 dolina, 842 15 Bratislava, Slovakia"},{"name":"National Sports Centre, Olympijsk\u00e9 n\u00e1mestie 14290\/1, 831 04 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Iveta","family":"Cihov\u00e1","sequence":"additional","affiliation":[{"name":"National Sports Centre, Olympijsk\u00e9 n\u00e1mestie 14290\/1, 831 04 Bratislava, Slovakia"},{"name":"Department of Track and Field, Faculty of Physical Education and Sports, Comenius University Bratislava, N\u00e1br. arm. gen. L. Svobodu 9, 814 69 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-2966-4597","authenticated-orcid":false,"given":"Michal","family":"Sot\u00e1k","sequence":"additional","affiliation":[{"name":"Department of Anthropology, Faculty of Natural Sciences, Comenius University Bratislava, Ilkovi\u010dova 6, Mlynsk\u00e1 dolina, 842 15 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2672-0965","authenticated-orcid":false,"given":"Darina","family":"Falbov\u00e1","sequence":"additional","affiliation":[{"name":"Department of Anthropology, Faculty of Natural Sciences, Comenius University Bratislava, Ilkovi\u010dova 6, Mlynsk\u00e1 dolina, 842 15 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-2211-1581","authenticated-orcid":false,"given":"Lenka","family":"Vorobe\u013eov\u00e1","sequence":"additional","affiliation":[{"name":"Department of Anthropology, Faculty of Natural Sciences, Comenius University Bratislava, Ilkovi\u010dova 6, Mlynsk\u00e1 dolina, 842 15 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5917-1689","authenticated-orcid":false,"given":"Radoslav","family":"Be\u0148u\u0161","sequence":"additional","affiliation":[{"name":"Department of Anthropology, Faculty of Natural Sciences, Comenius University Bratislava, Ilkovi\u010dova 6, Mlynsk\u00e1 dolina, 842 15 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-7941-2121","authenticated-orcid":false,"given":"Lucia","family":"Bundov\u00e1","sequence":"additional","affiliation":[{"name":"National Sports Centre, Olympijsk\u00e9 n\u00e1mestie 14290\/1, 831 04 Bratislava, Slovakia"},{"name":"Department of Pre-Primary and Primary Education, Faculty of Education, Comenius University Bratislava, \u0160olt\u00e9sovej 4, 811 08 Bratislava, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Yaneske, E., and Angione, C. 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