Clinical response of human subjects to rear-end automobile collisions.
OBJECTIVE
Forty-two persons were exposed to controlled low-speed rear-end automobile collisions to assess the relation between both gender and impact severity and the presence, severity, and duration of whiplash-associated disorders (WAD). Individual measures were also assessed for their potential to predict the onset of WAD.


METHODS
Experimental study subjecting individuals to a speed change of 4 km/h and 8 km/h and utilizing pretest and posttest physical examinations (immediately after and 24 hours after impact) to quantify subjects' clinical response.


RESULTS
Approximately 29% and 38% of the subjects exposed to the 4 km/h and 8 km/h speed changes, respectively, experienced WAD symptoms, with cervical symptoms and headaches predominating. Objective clinical deficits consistent with WAD were measured in both men and women subjects at both 4 km/h and 8 km/h. At 4 km/h, the duration of symptoms experienced by women was significantly longer when compared with that in men (p < .05). There were no significant differences in the presence and severity of WAD between men and women at 4 km/h and 8 km/h or in the duration of WAD at 8 km/h. There was also no significant difference in the presence, severity, and duration of WAD between 4 km/h and 8 km/h. No preimpact measures were predictive of WAD.


CONCLUSIONS
The empirical findings in this study contribute to establishing a causal relationship between rear-end collisions and clinical signs and symptoms.
Brault
J R
JR
Biomechanics Research & Consulting, Inc., El Segundo, CA 90245, USA.
Wheeler
J B
JB
Siegmund
G P
GP
Brault
E J
EJ
D000063:Accidents, Traffic; D000328:Adult; D000704:Analysis of Variance; D000886:Anthropometry; D001696:Biomechanical Phenomena; D004576:Electromyography; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D016015:Logistic Models; D008297:Male; D011237:Predictive Value of Tests; D016059:Range of Motion, Articular; D012727:Sex Characteristics; D012737:Sex Factors; D013997:Time Factors; D014911:Whiplash Injuries / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology