Investigation into Hand Impact Force During Forward Falls on Uneven Terrain

  • Saeed AbdolshahEmail author
  • Nader Rajaei
  • Yasuhiro Akiyama
  • Yoji Yamada
  • Shogo Okamoto
Regular Paper


Outdoor falls predominantly occur because of environmental factors, such as tripping caused by uneven terrain; as a result, the faller may land on an uneven surface. Forward falls are among the most frequent causes of fractures. Previous investigations concentrated on the evaluation of impact forces acting on the hand/wrist on even terrains; however, further studies are necessary to evaluate the impact force during forward falls on uneven surfaces, which may occur frequently in daily activities. This study investigated the distal/proximal hand impact force during forward falls on even/uneven terrain. A series of fall experiments in which the distal and proximal areas of the hand contacted the ground simultaneously (even surface) or at different times (uneven surface) was conducted. The results showed that the magnitude of the peak impact forces acting on the distal and proximal areas are strongly associated with the terrain shape and the contact timing. Although in all experiments, a significant portion of the impact force was exerted on the proximal area of the hand, the earlier distal-ground contact reduced the peak proximal impact force significantly. The results of this study are beneficial for finding strategies to reduce fall-related injuries and the design of protective gloves and wrist guards to satisfy fracture prevention requirements.


Forward fall Distal and proximal areas of the hand Impact force Uneven ground 



This work was supported by JSPS KAKENHI Grant Number 26750121 and 30813787, and METI (Ministry of Economy) “Strategic international standardization promotion project: International standardization of human tolerance against fall injuries”.

Compliance with Ethical Standards

Conflict of interest

The authors have no financial relationships that may cause a conflict of interest.


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Copyright information

© Korean Society for Precision Engineering 2019

Authors and Affiliations

  1. 1.Department of Mechanical Systems EngineeringNagoya UniversityNagoyaJapan

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