{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T15:00:57Z","timestamp":1784041257971,"version":"3.55.0"},"reference-count":53,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,5,28]],"date-time":"2025-05-28T00:00:00Z","timestamp":1748390400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Research Foundation (Deutsche Forschungsgemeinschaft, DFG)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Step width is an important clinical motor marker for gait stability assessment. While laboratory-based systems can measure it with high accuracy, wearable solutions based on inertial measurement units do not directly provide spatial information such as distances. Therefore, we propose a magnetic estimation approach based on a pair of shank-worn magnetoelectric (ME) sensors. In this pilot study, we estimated the step width of eight healthy participants during treadmill walking and compared it to an optical motion capture (OMC) reference. In a direct comparison with OMC markers attached to the magnetic system, we achieved a high estimation accuracy in terms of the mean absolute error (MAE) for step width (\u22641 cm) and step width variability (&lt;0.1 cm). In a more general comparison with heel-mounted markers during the swing phase, the standard deviation of the error (&lt;0.5 cm, measure for precision), the step width variability estimation MAE (&lt;0.2 cm) and the Spearman correlation (&gt;0.88) of individual feet were still encouraging, but the accuracy was negatively affected by a constant proxy bias (3.7 and 4.6 cm) due to the different anatomical reference points used in each method. The high accuracy of the system in the first case and the high precision in the second case underline the potential of magnetic motion tracking for gait stability assessment in wearable movement analysis.<\/jats:p>","DOI":"10.3390\/s25113390","type":"journal-article","created":{"date-parts":[[2025,5,28]],"date-time":"2025-05-28T08:12:47Z","timestamp":1748419967000},"page":"3390","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Pilot Study: Step Width Estimation with Body-Worn Magnetoelectric Sensors"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8170-8147","authenticated-orcid":false,"given":"Johannes","family":"Hoffmann","sequence":"first","affiliation":[{"name":"Department of Electrical and Information Engineering, Kiel University, 24143 Kiel , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7012-7707","authenticated-orcid":false,"given":"Erik","family":"Engelhardt","sequence":"additional","affiliation":[{"name":"Department of Electrical and Information Engineering, Kiel University, 24143 Kiel , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-7287-6397","authenticated-orcid":false,"given":"Moritz","family":"Boueke","sequence":"additional","affiliation":[{"name":"Department of Electrical and Information Engineering, Kiel University, 24143 Kiel , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8958-0934","authenticated-orcid":false,"given":"Julius","family":"Welzel","sequence":"additional","affiliation":[{"name":"Department of Neurology, University Hospital Schleswig-Holstein Campus Kiel and Kiel University, 24105 Kiel, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4813-3868","authenticated-orcid":false,"given":"Clint","family":"Hansen","sequence":"additional","affiliation":[{"name":"Department of Neurology, University Hospital Schleswig-Holstein Campus Kiel and Kiel University, 24105 Kiel, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5945-4694","authenticated-orcid":false,"given":"Walter","family":"Maetzler","sequence":"additional","affiliation":[{"name":"Department of Neurology, University Hospital Schleswig-Holstein Campus Kiel and Kiel University, 24105 Kiel, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6128-4831","authenticated-orcid":false,"given":"Gerhard","family":"Schmidt","sequence":"additional","affiliation":[{"name":"Department of Electrical and Information Engineering, Kiel University, 24143 Kiel , Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,28]]},"reference":[{"key":"ref_1","first-page":"843","article-title":"Gait Kinematic Parameters in Parkinson\u2019s Disease: A Systematic Review","volume":"10","author":"Jalles","year":"2020","journal-title":"J. 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