Related Experiment Video
Updated: Aug 14, 2026
Design and Analysis for Fall Detection System Simplification
Published on: April 6, 2020
Shock attenuation of various protective devices for prevention of fall-related injuries of the forearm/hand complex
Kyu-Jung Kim1, Ali M Alian, William S Morris
1Department of Mechanical Engineering, California State Polytechnic University-Pomona, 3801 West Temple Avenue, Pomona, CA 91768, USA. kyujungkim@csupomona.edu
Background:
Attenuation of the peak impact force is essential in any protective devices for prevention of fall-related injuries.
Hypothesis:
Common wrist guards have limited effectiveness because of the multifaceted nature of wrist injury mechanisms, and other modalities may provide enhanced shock-absorbing functions.
Study Design:
Controlled laboratory study.
Methods:
A free-fall device was constructed using a mechanical surrogate to simulate falling impact. At 4 different falling heights, 5 different hand conditions were tested: bare hand, a generic-brand wrist guard, a Sorbothane glove, an air cell, and an air bladder condition. The impact force from the ground and the transmitted impact force to the forearm/hand complex were simultaneously measured.
Results:
The falling height and hand condition significantly modulated the impact responses. The padded conditions always had significantly smaller peak impact forces compared with the bare-hand condition. The wrist guard became ineffective in impact force attenuation beyond the falling height of 51 cm. On the other hand, the air bladder condition maintained less than 45% of the peak impact force of the bare-hand condition and remained below the critical value, whereas other conditions were all ineffective.
Conclusion:
It was reconfirmed that common wrist guard design could provide limited impact force attenuation, whereas damped pneumatic springs would provide substantially enhanced shock-absorbing functions.
Clinical Relevance:
A wrist guard incorporating volar padding with the pneumatic spring design principle might be more effective at preventing injuries than are currently available designs.
