Limb Collapse or Instability? Assessment on Cause of Falls

  • Shuaijie Wang
  • Xuan Liu
  • Yi-Chung PaiEmail author


What causes an older adult to fall? Could the same factor lead to a recurring fall? The purposes of this study sought to address these questions by developing a causal-based assessment method for detection of the initial biomechanical cause of fall, and investigating the causation of 97 falls (out of 195 community dwelling older adults who participated in this study) based on this method. The unrecoverable limb collapse, or unrecoverable instability, along with its point of no return was defined, and the assessment method was established. Both the novel and the second slips of 97 participants who experienced laboratory induced slip related falls were assessed. The results showed that these older adults had more limb collapse (59.8%) initiated falls than instability (40.2%; and 32.0% of which from anteroposterior instability while only 8.2% from mediolateral instability) initiated falls. Interestingly, the majority (86.4%) of those 22 repeated fallers fell twice because of the same cause. These findings shed light on the vulnerability and the causation of recurring falls, which is one of the most challenging healthcare issues that an active but aging population is facing.


Recurrent falls Point-of-no-return Causation Vulnerability 



This work was supported by National Institute on Aging (NIH R01-AG029616 and NIH R01-AG044364). We thank Ms. Yiru Wang for helpful edits of an earlier version and Dr. Edward Wang for assistant on statistical analysis.


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Copyright information

© Biomedical Engineering Society 2019

Authors and Affiliations

  1. 1.Department of Physical TherapyUniversity of Illinois at ChicagoChicagoUSA
  2. 2.Human Performance and Engineering Research, Kessler FoundationWest OrangeUSA

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