{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T10:49:20Z","timestamp":1789728560904,"version":"4.0.1"},"reference-count":24,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2021,6,8]],"date-time":"2021-06-08T00:00:00Z","timestamp":1623110400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2021,6,8]],"date-time":"2021-06-08T00:00:00Z","timestamp":1623110400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100004243","name":"Prinses Beatrix Spierfonds","doi-asserted-by":"publisher","award":["W.OR 14-21"],"award-info":[{"award-number":["W.OR 14-21"]}],"id":[{"id":"10.13039\/501100004243","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["J NeuroEngineering Rehabil"],"published-print":{"date-parts":[[2021,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Background<\/jats:title>\n                <jats:p>In people with calf muscle weakness, the stiffness of dorsal leaf spring ankle\u2013foot orthoses (DLS-AFO) needs to be individualized to maximize its effect on walking. Orthotic suppliers may recommend a certain stiffness based on body weight and activity level. However, it is unknown whether these recommendations are sufficient to yield the optimal stiffness for the individual. Therefore, we assessed whether the stiffness following the supplier\u2019s recommendation of the Carbon Ankle7 (CA7) dorsal leaf matched the experimentally optimized AFO stiffness.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>Thirty-four persons with calf muscle weakness were included and provided a new DLS-AFO of which the stiffness could be varied by changing the CA7\u00ae (Ottobock, Duderstadt, Germany) dorsal leaf. For five different stiffness levels, including the supplier recommended stiffness, gait biomechanics, walking energy cost and speed were assessed. Based on these measures, the individual experimentally optimal AFO stiffness was selected.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>In only 8 of 34 (23%) participants, the supplier recommended stiffness matched the experimentally optimized AFO stiffness, the latter being on average 1.2\u2009\u00b1\u20091.3 Nm\/degree more flexible. The DLS-AFO with an experimentally optimized stiffness resulted in a significantly lower walking energy cost (\u2212\u00a00.21\u2009\u00b1\u20090.26\u00a0J\/kg\/m, <jats:italic>p<\/jats:italic>\u2009&lt;\u20090.001) and a higher speed (+\u20090.02\u00a0m\/s, <jats:italic>p<\/jats:italic>\u2009=\u20090.003). Additionally, a larger ankle range of motion (+\u20091.3\u2009\u00b1\u20090.3 degrees, <jats:italic>p<\/jats:italic>\u2009&lt;\u20090.001) and higher ankle power (+\u20090.16\u2009\u00b1\u20090.04\u00a0W\/kg, <jats:italic>p<\/jats:italic>\u2009&lt;\u20090.001) were found with the experimentally optimized stiffness compared to the supplier recommended stiffness.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>In people with calf muscle weakness, current supplier\u2019s recommendations for the CA7 stiffness level result in the provision of DLS-AFOs that are too stiff and only achieve 80% of the reduction in energy cost achieved with an individual optimized stiffness. It is recommended to experimentally optimize the CA7 stiffness in people with calf muscle weakness in order to maximize treatment outcomes.<\/jats:p>\n                <jats:p><jats:italic>Trial registration<\/jats:italic> Nederlands Trial Register 5170. Registration date: May 7th 2015. <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"uri\" xlink:href=\"http:\/\/www.trialregister.nl\/trialreg\/admin\/rctview.asp?TC=5170\">http:\/\/www.trialregister.nl\/trialreg\/admin\/rctview.asp?TC=5170<\/jats:ext-link>.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s12984-021-00890-8","type":"journal-article","created":{"date-parts":[[2021,6,8]],"date-time":"2021-06-08T09:05:30Z","timestamp":1623143130000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Individual stiffness optimization of dorsal leaf spring ankle\u2013foot orthoses in people with calf muscle weakness is superior to standard bodyweight-based recommendations"],"prefix":"10.1186","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4025-7137","authenticated-orcid":false,"given":"Niels F. 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The study protocol of the PROOF-AFO trial was approved by the medical ethics committee of the Academic Medical Center (AMC) in Amsterdam, The Netherlands (register: METC_2014_397).","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare that they have no competing interest.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"97"}}