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Existing methods often isolate the analysis of gait variables, overlooking the whole complexity of biomechanical patterns and variations in motor control strategies. While previous studies have explored the use of statistical physics principles for the analysis of impaired gait patterns, gaps remain in integrating both kinematic and kinetic information or benchmarking these approaches against Deep Learning models. This study evaluates the robustness of statistical physics metrics in differentiating between normal and abnormal gait patterns and quantifies how the data source affects model performance. The analysis was conducted using gait data sets from two research institutions in Madrid and Dublin, with a total of 81 children with ITW, 300 with CP, 20 with HSP, and 127 typically developing children as controls. From each kinematic and kinetic time series, Shannon\u2019s entropy, permutation entropy, weighted permutation entropy, and time irreversibility metrics were derived and used with Random Forest models. The classification accuracy of these features was compared to a ResNet Deep Learning model. Further analyses explored the effects of inter-laboratory comparisons and the spatiotemporal resolution of time series on classification performance and evaluated the impact of age and walking speed with linear mixed models. The results revealed that statistical physics metrics were able to differentiate among impaired gait patterns, achieving classification scores comparable to ResNet. The effects of walking speed and age on gait predictability and temporal organisation were observed as disease-specific patterns. However, performance differences across laboratories limit the generalisation of the trained models. These findings highlight the value of statistical physics metrics in the classification of children with different toe walking conditions and point towards the need of multimetric integration to improve diagnostic accuracy and gain a more comprehensive understanding of gait disorders.<\/jats:p>","DOI":"10.3390\/s25134235","type":"journal-article","created":{"date-parts":[[2025,7,7]],"date-time":"2025-07-07T10:03:27Z","timestamp":1751882607000},"page":"4235","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Entropy, Irreversibility, and Time-Series Deep Learning of Kinematic and Kinetic Data for Gait Classification in Children with Cerebral Palsy, Idiopathic Toe Walking, and Hereditary Spastic Paraplegia"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4093-9875","authenticated-orcid":false,"given":"Alfonso","family":"de Gorostegui","sequence":"first","affiliation":[{"name":"PhD Program in Neuroscience, Universidad Autonoma de Madrid-Cajal Institute, 28029 Madrid, Spain"},{"name":"Department of Anatomy, Histology & Neuroscience, School of Medicine, Universidad Aut\u00f3noma de Madrid (UAM), 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5839-0393","authenticated-orcid":false,"given":"Massimiliano","family":"Zanin","sequence":"additional","affiliation":[{"name":"Instituto de F\u00edsica Interdisciplinar y Sistemas Complejos IFISC (CSIC-UIB), Campus UIB, 07122 Palma de Mallorca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4949-0843","authenticated-orcid":false,"given":"Juan-Andr\u00e9s","family":"Mart\u00edn-Gonzalo","sequence":"additional","affiliation":[{"name":"Escuela Universitaria de Fisioterapia de la ONCE, Universidad Aut\u00f3noma de Madrid, 28034 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9315-1048","authenticated-orcid":false,"given":"Javier","family":"L\u00f3pez-L\u00f3pez","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation, Hospital Universitario Infanta Sof\u00eda, 28702 Madrid, Spain"},{"name":"Fundaci\u00f3n para la Investigaci\u00f3n e Innovaci\u00f3n Biom\u00e9dica del Hospital Universitario Infanta Sof\u00eda y Hospital del Henares, 28702 Madrid, Spain"},{"name":"Departamento de Medicina, Salud y Deporte, Universidad Europea de Madrid, Villaviciosa de Od\u00f3n, 28670 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5654-7791","authenticated-orcid":false,"given":"David","family":"G\u00f3mez-Andr\u00e9s","sequence":"additional","affiliation":[{"name":"Pediatric Neurology, ERN-RND, Euro-NMD, Vall d\u2019Hebron Institut de Recerca (VHIR), Hospital Universitari Vall d\u2019Hebron, 08035 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5785-8831","authenticated-orcid":false,"given":"Damien","family":"Kiernan","sequence":"additional","affiliation":[{"name":"Movement Analysis Laboratory, Central Remedial Clinic, Clontarf, D03 R973 Dublin, Ireland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1129-7116","authenticated-orcid":false,"given":"Estrella","family":"Rausell","sequence":"additional","affiliation":[{"name":"Department of Anatomy, Histology & Neuroscience, School of Medicine, Universidad Aut\u00f3noma de Madrid (UAM), 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1053\/apmr.2003.50057","article-title":"Toe walking: Muscular demands at the ankle and knee","volume":"84","author":"Perry","year":"2003","journal-title":"Arch. 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