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Injury risk function for the small female wrist in axial loading
Stefan M Duma1, Brian M Boggess, Jeff R Crandall
1Virginia Tech, Impact Biomechanics Laboratory, Mechanical Engineering, 114 Randolph Hall, Blacksburg, VA 24061, USA. duma@vt.edu
Accident; Analysis and Prevention
|September 16, 2003
Summary
Researchers developed an injury tolerance for the small female wrist to improve side airbag design. A 1700 N wrist load predicts a 50% injury risk, helping reduce automotive crash injuries.
Area of Science:
- Biomechanics
- Automotive Safety Engineering
Background:
- Side airbag deployment poses a risk of wrist entrapment and injury.
- Previous studies indicated potential for wrist injuries in human cadavers exposed to side airbags.
Purpose of the Study:
- To develop an injury tolerance for the small female wrist.
- To inform the design of side airbags to mitigate wrist injury risk during deployment.
Main Methods:
- Axial impact experiments were conducted on 17 small female cadaver wrists.
- A pneumatic impactor simulated the load profile of a deploying side airbag.
- Logistic regression analysis was used to develop an injury risk function.
Main Results:
- Nine out of 17 tests resulted in wrist injuries, including fractures of the scaphoid, lunate, distal radius, and distal ulna.
- An injury risk function was developed, predicting a 50% risk of injury at a wrist load of 1700 N.
- Injury risk was not significantly dependent on bone mineral density, age, mass, or stature.
Conclusions:
- The developed injury risk function can accurately predict wrist injury risk in automotive crash scenarios.
- Findings suggest specific load thresholds for side airbag design to protect the small female wrist.
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