{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,24]],"date-time":"2025-12-24T12:21:03Z","timestamp":1766578863684,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2024,6,6]],"date-time":"2024-06-06T00:00:00Z","timestamp":1717632000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the German Federal Ministry for Education and Science","award":["01EO1401","13GW0490B"],"award-info":[{"award-number":["01EO1401","13GW0490B"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Postural instability is a common complication in advanced Parkinson\u2019s disease (PD) associated with recurrent falls and fall-related injuries. The test of retropulsion, consisting of a rapid balance perturbation by a pull in the backward direction, is regarded as the gold standard for evaluating postural instability in PD and is a key component of the neurological examination and clinical rating in PD (e.g., MDS-UPDRS). However, significant variability in test execution and interpretation contributes to a low intra- and inter-rater test reliability. Here, we explore the potential for objective, vision-based assessment of the pull test (vPull) using 3D pose tracking applied to single-sensor RGB-Depth recordings of clinical assessments. The initial results in a cohort of healthy individuals (n = 15) demonstrate overall excellent agreement of vPull-derived metrics with the gold standard marker-based motion capture. Subsequently, in a cohort of PD patients and controls (n = 15 each), we assessed the inter-rater reliability of vPull and analyzed PD-related impairments in postural response (including pull-to-step latency, number of steps, retropulsion angle). These quantitative metrics effectively distinguish healthy performance from and within varying degrees of postural impairment in PD. vPull shows promise for straightforward clinical implementation with the potential to enhance the sensitivity and specificity of postural instability assessment and fall risk prediction in PD.<\/jats:p>","DOI":"10.3390\/s24113673","type":"journal-article","created":{"date-parts":[[2024,6,6]],"date-time":"2024-06-06T03:44:35Z","timestamp":1717645475000},"page":"3673","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Precision Balance Assessment in Parkinson\u2019s Disease: Utilizing Vision-Based 3D Pose Tracking for Pull Test Analysis"],"prefix":"10.3390","volume":"24","author":[{"given":"Nina","family":"Ellrich","sequence":"first","affiliation":[{"name":"German Center for Vertigo and Balance Disorders (DSGZ), LMU University Hospital, LMU Munich, 81377 Munich, Germany"}]},{"given":"Kasimir","family":"Niermeyer","sequence":"additional","affiliation":[{"name":"German Center for Vertigo and Balance Disorders (DSGZ), LMU University Hospital, LMU Munich, 81377 Munich, Germany"}]},{"given":"Daniela","family":"Peto","sequence":"additional","affiliation":[{"name":"German Center for Vertigo and Balance Disorders (DSGZ), LMU University Hospital, LMU Munich, 81377 Munich, Germany"}]},{"given":"Julian","family":"Decker","sequence":"additional","affiliation":[{"name":"German Center for Vertigo and Balance Disorders (DSGZ), LMU University Hospital, LMU Munich, 81377 Munich, Germany"},{"name":"Schoen Clinic Bad Aibling, 83043 Bad Aibling, Germany"}]},{"given":"Urban M.","family":"Fietzek","sequence":"additional","affiliation":[{"name":"Department of Neurology, LMU University Hospital, LMU Munich, 81377 Munich, Germany"},{"name":"Schoen Clinic M\u00fcnchen Schwabing, 80804 Munich, Germany"}]},{"given":"Sabrina","family":"Katzdobler","sequence":"additional","affiliation":[{"name":"Department of Neurology, LMU University Hospital, LMU Munich, 81377 Munich, Germany"},{"name":"German Center for Neurodegenerative Diseases (DZNE) e.V., 81377 Munich, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7587-6187","authenticated-orcid":false,"given":"G\u00fcnter U.","family":"H\u00f6glinger","sequence":"additional","affiliation":[{"name":"Department of Neurology, LMU University Hospital, LMU Munich, 81377 Munich, Germany"},{"name":"German Center for Neurodegenerative Diseases (DZNE) e.V., 81377 Munich, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1669-3652","authenticated-orcid":false,"given":"Klaus","family":"Jahn","sequence":"additional","affiliation":[{"name":"German Center for Vertigo and Balance Disorders (DSGZ), LMU University Hospital, LMU Munich, 81377 Munich, Germany"},{"name":"Schoen Clinic Bad Aibling, 83043 Bad Aibling, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3839-8398","authenticated-orcid":false,"given":"Andreas","family":"Zwergal","sequence":"additional","affiliation":[{"name":"German Center for Vertigo and Balance Disorders (DSGZ), LMU University Hospital, LMU Munich, 81377 Munich, Germany"},{"name":"Department of Neurology, LMU University Hospital, LMU Munich, 81377 Munich, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5115-3777","authenticated-orcid":false,"given":"Max","family":"Wuehr","sequence":"additional","affiliation":[{"name":"German Center for Vertigo and Balance Disorders (DSGZ), LMU University Hospital, LMU Munich, 81377 Munich, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1016\/0303-8467(92)90018-X","article-title":"Postural instability in Parkinson\u2019s disease","volume":"94","author":"Bloem","year":"1992","journal-title":"Clin. 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