{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T03:36:40Z","timestamp":1769571400094,"version":"3.49.0"},"reference-count":43,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,3,22]],"date-time":"2022-03-22T00:00:00Z","timestamp":1647907200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Interreg FWVl","award":["NOMADe N\u00b0 4.7.360"],"award-info":[{"award-number":["NOMADe N\u00b0 4.7.360"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Low back pain (LBP) obviously reduces the quality of life but is also the world\u2019s leading cause of years lived with disability. Alterations in motor response and changes in movement patterns are expected in LBP patients when compared to healthy people. Such changes in dynamics may be assessed by the nonlinear analysis of kinematical time series recorded from one patient\u2019s motion. Since sample entropy (SampEn) has emerged as a relevant index measuring the complexity of a given time series, we propose the development of a clinical test based on SampEn of a time series recorded by a wearable inertial measurement unit for repeated bending and returns (b and r) of the trunk. Twenty-three healthy participants were asked to perform, in random order, 50 repetitions of this movement by touching a stool and another 50 repetitions by touching a box on the floor. The angular amplitude of the b and r movement and the sample entropy of the three components of the angular velocity and acceleration were computed. We showed that the repetitive b and r \u201ctouch the stool\u201d test could indeed be the basis of a clinical test for the evaluation of low-back-pain patients, with an optimal duration of 70 s, acceptable in daily clinical practice.<\/jats:p>","DOI":"10.3390\/e24040437","type":"journal-article","created":{"date-parts":[[2022,3,22]],"date-time":"2022-03-22T14:55:35Z","timestamp":1647960935000},"page":"437","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Sample Entropy as a Tool to Assess Lumbo-Pelvic Movements in a Clinical Test for Low-Back-Pain Patients"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3948-0393","authenticated-orcid":false,"given":"Paul","family":"Thiry","sequence":"first","affiliation":[{"name":"LAMIH, CNRS, UMR 8201, Universit\u00e9 Polytechnique Hauts-de-France, F-59313 Valenciennes, France"},{"name":"CHU Lille, Universit\u00e9 de Lille, F-59000 Lille, France"},{"name":"CeREF Technique, Chauss\u00e9e de Binche 159, 7000 Mons, Belgium"}]},{"given":"Olivier","family":"Nocent","sequence":"additional","affiliation":[{"name":"PSMS, Universit\u00e9 de Reims Champagne Ardenne, F-51867 Reims, France"}]},{"given":"Fabien","family":"Buisseret","sequence":"additional","affiliation":[{"name":"CeREF Technique, Chauss\u00e9e de Binche 159, 7000 Mons, Belgium"},{"name":"Service de Physique Nucl\u00e9aire et Subnucl\u00e9aire, Universit\u00e9 de Mons, UMONS Research Institute for Complex Systems, 20 Place du Parc, 7000 Mons, Belgium"}]},{"given":"William","family":"Bertucci","sequence":"additional","affiliation":[{"name":"PSMS, Universit\u00e9 de Reims Champagne Ardenne, F-51867 Reims, France"}]},{"given":"Andr\u00e9","family":"Thevenon","sequence":"additional","affiliation":[{"name":"CHU Lille, Universit\u00e9 de Lille, F-59000 Lille, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2059-884X","authenticated-orcid":false,"given":"Emilie","family":"Simoneau-Buessinger","sequence":"additional","affiliation":[{"name":"LAMIH, CNRS, UMR 8201, Universit\u00e9 Polytechnique Hauts-de-France, F-59313 Valenciennes, France"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2356","DOI":"10.1016\/S0140-6736(18)30480-X","article-title":"What Low Back Pain Is and Why We Need to Pay Attention","volume":"391","author":"Hartvigsen","year":"2018","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"743","DOI":"10.1016\/S0140-6736(15)60692-4","article-title":"Global, Regional, and National Incidence, Prevalence, and Years Lived with Disability for 301 Acute and Chronic Diseases and Injuries in 188 Countries, 1990\u20132013: A Systematic Analysis for the Global Burden of Disease Study 2013","volume":"386","author":"Vos","year":"2015","journal-title":"Lancet"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Artus, M., Campbell, P., Mallen, C.D., Dunn, K.M., and van der Windt, D.A.W. 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