Citation

Hernández IA, Fyfe KR, Heo G, Major PW. Eur. Spine J. 2006; 15(6): 876-885.

Affiliation

Department of Dentistry, Faculty of Medicine and Dentistry, Dentistry/Pharmacy Centre, University of Alberta, Room 4051b, Edmonton, Alberta, T6G 2N8, Canada.

Copyright

(Copyright © 2006, Holtzbrinck Springer Nature Publishing Group)

DOI

10.1007/s00586-005-0956-9

PMID

16133079

Abstract

The objectives of this study were to evaluate behavior of sternocleidomastoid muscle (SCM) electromyogram (EMG) related to impact velocity, gender, awareness and kinematics of head movement in simulated low velocity rear-end impacts. Twenty-nine healthy adults (17 male) were subjected in random order to three rear-end impacts: Two unexpected impacts causing chair accelerations of 4.5 m/s(2) (slow) and 10.1 m/s(2) (fast) and one 10.1 m/s(2) expected impact. Normalized left and right SCM EMG, linear head acceleration, angular head acceleration and maximum angular head displacement were recorded. The magnitude of normalized SCM EMG peak response ranged 2-3 times higher (P< 0.001) in female subjects than their counterpart male subjects. SCM EMG magnitude was 3-4 times higher (P< 0.001) for the fast unexpected than slow unexpected impacts, but there was no significant difference (P> 0.05) for the fast expected compared to the fast unexpected impacts. The onset time of SCM peak EMG ranged from 78 ms to 114 ms later than peak of linear head acceleration for all groups. Onset time of peak SCM EMG was not significantly different (P> 0.05) than onset of angular acceleration for the slow and fast-unexpected impacts, but onset peak SCM EMG was significantly earlier than peak angular head acceleration (30 ms) (P

Language: en