{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T01:22:34Z","timestamp":1787016154615,"version":"build-2736575974"},"reference-count":32,"publisher":"ASME International","issue":"10","license":[{"start":{"date-parts":[[2020,7,17]],"date-time":"2020-07-17T00:00:00Z","timestamp":1594944000000},"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":[[2020,10,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Falling backward can lead to injuries including hip fracture, back injury, and traumatic brain impact among older adults. A loss of consciousness is associated with falling backward and accounts for about 13% of all falls among older adults. Little is known about the dynamics of backward falls, such as the falling duration, the impact severity, and how the fall dynamics are affected by the biomechanical properties of the lower limb joints, particularly the rotational stiffness. The purpose of this study was to investigate the influence of the stiffness of individual leg joints on the dynamics of backward falls after losing consciousness in terms of the falling duration and impact velocities. Based on a 15-segment human model, we simulated the process of falling backward by sweeping the parameter space of ankle, knee, and hip's stiffnesses varying from 0 to 8.73 N\u00b7m\u00b7deg\u22121 (or 500 N\u00b7m\u00b7rad\u22121). The results revealed that the falling duration and impact speeds of the head and hip ranged from 0.27 to 0.63\u2009s, 2.65 to 7.88\u2009m\u00b7s\u22121, and 0.35 to 3.36\u2009m\u00b7s\u22121, respectively, when the stiffness of the leg joints changed within their limits. Overall, the influence of the joint stiffness on the falling dynamics (falling duration and impact speed) is comparable between hip and knee joints, whereas ankle stiffness showed little influence on the backward falling dynamics. Our findings could provide references for designing protective devices to prevent impact-induced injuries after a backward fall.<\/jats:p>","DOI":"10.1115\/1.4047077","type":"journal-article","created":{"date-parts":[[2020,4,29]],"date-time":"2020-04-29T03:18:54Z","timestamp":1588130334000},"update-policy":"https:\/\/doi.org\/10.1115\/crossmarkpolicy-asme","source":"Crossref","is-referenced-by-count":16,"title":["Leg Joint Stiffness Affects Dynamics of Backward Falling From Standing Height: A Simulation Work"],"prefix":"10.1115","volume":"142","author":[{"given":"Mu","family":"Qiao","sequence":"first","affiliation":[{"name":"Department of Kinesiology, Louisiana Tech University, Scotty Robertson Memorial Gym, Rm-236, Ruston, LA 71272"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Feng","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Kinesiology and Health, Georgia State University, 125 Decatur St. SE, Suite-137, Atlanta, GA 30303"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"33","published-online":{"date-parts":[[2020,7,17]]},"reference":[{"issue":"3","key":"2022040715095863000_bib1","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1001\/jama.2009.2024","article-title":"The Patient Who Falls: \u2018It\u2019s Always a Trade-Off'","volume":"303","year":"2010","journal-title":"JAMA"},{"issue":"5","key":"2022040715095863000_bib2","doi-asserted-by":"crossref","first-page":"1794","DOI":"10.1111\/1475-6773.12554","article-title":"The Costs of Fall-Related Injuries Among Older Adults: Annual per-Faller, Service Component, and Patient Out-of-Pocket Costs","volume":"52","year":"2017","journal-title":"Health Serv. 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