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CC BY 4.0 · Ultraschall Med
DOI: 10.1055/a-2675-5871
Original Article

Medial Plantar Proper Digital Nerve Thickening – a Sonographic Finding in Volunteers Without Joplin’s Neuroma

Verdickung des medialen plantaren Digitalnervs – ein sonografischer Befund bei Probanden ohne Joplin-Neurom

Authors

  • Veronika Vetchy 

    1   Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria

  • Tobias Rossmann

    2   Department of Neurosurgery, Neuromed Campus, Kepler University Hospital, Linz, Austria (Ringgold ID: RIN31197)
    3   Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria

  • Paata Pruidze

    3   Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria

  • Wolfgang Grisold

    4   Neurology Consultancy Unit, Division of Anatomy, Medical University of Vienna, Vienna, Austria (Ringgold ID: RIN27271)

  • Wolfgang Weninger

    3   Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria

  • Stefan Meng 

    3   Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
    5   Radiology, Hanusch Hospital, Wien, Austria (Ringgold ID: RIN31315)
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Abstract

Purpose

Thickening of the medial plantar proper digital nerve (MPPDN) along the medial aspect of the big toe is frequently observed incidentally during high-resolution ultrasound examinations in asymptomatic individuals. However, the clinical significance of these findings remains unclear, as no study has definitively linked them to symptoms. Although the localization and visualization of the medial plantar nerve using ultrasound have been documented, its cross-sectional area has not yet been utilized to assess thickening at this specific site. The study aimed to assess the frequency and specific locations of MPPDN thickening in asymptomatic individuals and to identify associated characteristics.

Materials & Methods

In this prospective study, high-resolution ultrasound examination of the MPPDN was performed on asymptomatic volunteers. The cross-sectional areas and their changes along the course of the nerve are evaluated descriptively. Potential contributing demographic factors in participants are captured.

Results

56 asymptomatic volunteers, 30 women and 26 men (median age: 28, range: 20–69) participated in this study. 22 individuals (39.3%) showed thickening of the MPPDN at the interphalangeal joint either in one or both feet. More participants above the median population age of 28 showed thickening of the MPPDN (15 [57.7%] versus 7 [23.3%] p = 0.009).

Conclusion

Thickening of the MPPDN is frequently observed in asymptomatic individuals, with the likelihood of these findings increasing with age. The pathological significance should however not be overestimated and should be assessed in a clinical context.

Zusammenfassung

Ziel

Eine Verdickung des medialen plantaren Digitalnervs (MPPDN) entlang der Großzehe wird bei beschwerdefreien Personen häufig zufällig bei Ultraschalluntersuchungen beobachtet. Die klinische Bedeutung ist bisher unklar, da keine Studie diese Veränderungen eindeutig mit Symptomen verknüpft hat. Ziel war die Erfassung der Häufigkeit und Lokalisation der MPPDN-Verdickungen bei asymptomatischen Individuen und die Identifikation assoziierter Patientencharakteristika.

Material und Methoden

In dieser prospektiven Studie wurde eine hochauflösende Ultraschalluntersuchung des Nervs bei asymptomatischen Freiwilligen durchgeführt. Die Querschnittsflächen und deren Veränderungen entlang des Nervenverlaufs wurden deskriptiv ausgewertet und mögliche demografische Faktoren erfasst.

Ergebnisse

Sechsundfünfzig asymptomatische Freiwillige, 30 Frauen und 26 Männer (medianes Alter 28, Bandbreite 20–69), nahmen teil. Bei 22 Personen (39,3%) zeigte sich eine Verdickung im Bereich des ersten Interphalangealgelenks in einem oder beiden Füßen. Über dem medianen Alter von 28 Jahren wiesen mehr Patienten eine MPPDN-Verdickung auf (15 [57,7] versus 7 [23,3] p = 0.009).

Schlussfolgerungen

Die Verdickung des medialen plantaren Digitalnervs wird häufig bei asymptomatischen Personen beobachtet, wobei die Wahrscheinlichkeit mit steigendem Alter zunimmt. Die pathologische Bedeutung sollte jedoch nicht überbewertet und im klinischen Kontext beurteilt werden.

Keywords

medial plantar nerve - nerve thickening - asymptomatic - medial proper plantar digital nerve - high-resolution ultrasound


Publication History

Received: 30 May 2025

Accepted after revision: 31 July 2025

Article published online:
14 January 2026

© 2026. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/).

Georg Thieme Verlag KG
Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany

 

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