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Updated: Aug 26, 2026

A Test Bed to Examine Helmet Fit and Retention and Biomechanical Measures of Head and Neck Injury in Simulated Impact
Published on: September 21, 2017
Chronic whiplash associated disorders and neck movement measurements: an instantaneous helical axis approach
Fredrik Ohberg1, Helena Grip, Urban Wiklund
1Department of Biomedical Engineering and Informatics, University Hospital, Umeå SE-90185, Sweden. Fredrik.Ohberg@vll.se
Abstract:
This paper presents an assessment tool for objective neck movement analysis of subjects suffering from chronic whiplash-associated disorders (WAD). Three-dimensional (3-D) motion data is collected by a commercially available motion analysis system. Head rotation, defined in this paper as the rotation angle around the instantaneous helical axis (IHA), is used for extracting a number of variables (e.g., angular velocity and range, symmetry of motion). Statistically significant differences were found between controls and subjects with chronic WAD in a number of variables.
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