{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T10:49:07Z","timestamp":1789728547681,"version":"4.0.1"},"reference-count":56,"publisher":"ASME International","issue":"1","license":[{"start":{"date-parts":[[2021,9,1]],"date-time":"2021-09-01T00:00:00Z","timestamp":1630454400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.asme.org\/publications-submissions\/publishing-information\/legal-policies"}],"content-domain":{"domain":["asmedigitalcollection.asme.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2022,1,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The mechanical properties of an ankle-foot orthosis (AFO) can impact how a user's movement is either restricted or augmented by the device. However, standardized methods for assessing stiffness properties of AFOs are lacking, posing a challenge for comparing between devices and across vendors. Therefore, the purpose of this study was to quantify the rotational stiffness of thirteen commercial, nonarticulated, carbon composite ankle-foot orthoses. A custom, instrumented test fixture, for evaluating mechanical properties in rotating exoskeletons (EMPIRE), deflected an AFO through 20\u2009deg of plantar\/dorsiflexion motion about a specified, but adjustable, ankle axis. Sagittal, frontal, and transverse plane rotational stiffness were calculated, and reliability was assessed between cycles, sessions, and testers. The EMPIRE demonstrated good-to-excellent reliability between testers, sessions, and cycles (intraclass correlation coefficients all \u22650.95 for sagittal plane stiffness measures). Sagittal plane AFO stiffness ranged from 0.58 N\u00b7m\/deg to 3.66 N\u00b7m\/deg. AFOs with a lateral strut demonstrated frontal plane stiffnesses up to 0.71 N\u00b7m\/deg of eversion while those with a medial strut demonstrated frontal plane stiffnesses up to 0.53 N\u00b7m\/deg of inversion. Transverse plane stiffnesses were less than 0.30 N\u00b7m\/deg of internal or external rotation. These results directly compare AFOs of different models and from different manufacturers using consistent methodology and are intended as a resource for clinicians in identifying a device with stiffness properties for individual patients.<\/jats:p>","DOI":"10.1115\/1.4051845","type":"journal-article","created":{"date-parts":[[2021,7,21]],"date-time":"2021-07-21T06:21:55Z","timestamp":1626848515000},"update-policy":"https:\/\/doi.org\/10.1115\/crossmarkpolicy-asme","source":"Crossref","is-referenced-by-count":23,"title":["Multiplanar Stiffness of Commercial Carbon Composite Ankle-Foot Orthoses"],"prefix":"10.1115","volume":"144","author":[{"given":"Benjamin R.","family":"Shuman","sequence":"first","affiliation":[{"name":"DoD-VA Extremity Trauma and Amputation Center of Excellence, San Antonio, TX 78234; Center for Limb Loss and Mobility, VA Puget Sound, 1660 S Columbian Way, Seattle, WA 98108"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elizabeth","family":"Russell Esposito","sequence":"additional","affiliation":[{"name":"DoD-VA Extremity Trauma and Amputation Center of Excellence, San Antonio, TX 78234; Center for Limb Loss and Mobility, VA Puget Sound, 660 S Columbian Way, Seattle, WA 98108; Department of Mechanical Engineering, University of Washington, Seattle, WA 98195"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"33","published-online":{"date-parts":[[2021,9,1]]},"reference":[{"issue":"2","key":"2021090112460316800_bib1","doi-asserted-by":"crossref","first-page":"132","DOI":"10.3109\/03093649609164431","article-title":"Stiffness Control in Posterior-Type Plastic Ankle-Foot Orthoses: Effect of Ankle Trimline Part 2: Orthosis Characteristics and Orthosis\/Patient Matching","volume":"20","year":"1996","journal-title":"Prosthet. 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