Evidence map›Paper›PMID 42745291›Full record

ArticleBMC sports science, medicine & rehabilitation2026

Two-year follow-up of varus progression in young professional football players.

Hannah Gablac, Lars Schwalm, Peter Behrendt, Michael Hoffmann, Matthias Krause, Karl-Heinz Frosch, Götz Welsch, Dimitris Dalos

Abstract read
In one paragraph

Article in BMC sports science, medicine & rehabilitation, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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2 · The registry

The trial behind it

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3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Hannah GablacMuskuloskelettales Universitätszentrum München, Ludwig-Maximilians- Universität München, Munich, Germany.ORCID http://orcid.org/0009-0004-5686-1317
Lars SchwalmInstitute of Interdisciplinary Exercise Science and Sports Medicine, MSH Medical School Hamburg, Hamburg, Germany.
Peter BehrendtDepartment of Trauma and Orthopaedic Surgery, University Medical Center Schleswig-Hohlstein, Kiel, Germany.
Michael HoffmannSanatorium Dr. Schenk GmbH, Montafonerstraße 29, Schruns, 6780, Austria.
Matthias KrauseDepartment of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Karl-Heinz FroschDepartment of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Götz WelschUKE Athleticum - Center for Athletic Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Dimitris DalosUKE Athleticum - Center for Athletic Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. dimitris.dalos@medicalschool-hamburg.de.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeProfessional football players have an increased prevalence of genu varum, which is a risk factor for developing knee osteoarthritis. It remains unclear at what stage of adolescence varus progression is most pronounced and which factors are associated with this progression. Therefore, this study aimed to investigate the factors associated with varus progression over a two-year observation period in a selected cohort of adolescent male professional academy football players.

methodsA total of 31 male youth academy football players aged 12-17 years who demonstrated varus progression during the oberservation period were included. The static mean mechanical femorotibial axis angle (MAA) of both legs was measured using a two-dimensional and marker-based method (DIERS leg axis analysis system). Players' age, height, BMI and dominant kicking leg were also assessed. Measurements were performed in 2021 and after a 24-month observation period. Changes and correlations over the observation period were statistically analyzed using SPSS.

resultsAge-related differences were observed in the extent of MAA: the youngest athletes had the lowest MAA at baseline (p = 0.049), which increased more over the following two years than the older players. Greater increases in height during the observation period (p = 0.008), low initial height (p = 0.035), BMI (p = 0.043) and less varus deformity (p = 0.017) were found to be significant factors associated with an increase in MAA.

conclusionWithin this selected cohort, the increase in MAA over the two-year observation period was most pronounced in the younger athletes. Greater increases in height and associated weight gain were the variables most strongly associated with increasing varus alignment during the observation period. These findings may help to inform the timing of future preventive strategies, although their effectiveness for influencing leg-axis development remains to be established.

Indexed as

Bow legsFootballGenu varumLeg axisOsteoarthritisSoccer

Identifiers

PMID42745291
PMCPMC13576229

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.