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Assessing automobile head restraint positioning in Portland, Oregon
1Department of Neurosurgery, Oregon Health Sciences University, Portland, OR 97201, USA.
Objective:
Automobile head restraints, when used properly, have been shown to decrease the incidence and severity of whiplash injuries to the neck. Before the development of a public campaign on proper head restraint positioning, the authors assessed head restraint positioning and public understanding.
Design:
Over a one month period, the position of the vehicle head restraint of drivers was observed in moving cars in the city of Portland, Oregon (population 530,000). Optimal position was defined as having the head restraint above the ears with the back of the head touching the head restraint. A questionnaire on head restraint understanding was administered to people during jury service.
Results:
Of the 4287 drivers observed, 1% (n = 30) had no head restraint on their seat, 4% (n = 158) had a fixed head restraint, and 95% (n = 4099) had an adjustable head restraint. Among the fixed head restraints, 21% (33/158) were positioned optimally with no horizontal gap. Among the adjustable head restraints, only 7% (280/4099) had optimal head restraint positioning. Overall, 93% (3974/4287) of all head restraints observed were suboptimally positioned. Seventy five percent (38/51) of polled Portland residents identified safety as the primary head restraint function.
Conclusion:
Ninety three percent of all head restraints observed were suboptimally positioned. Fixed head restraints were three times more likely to be in optimal position than adjustable head restraints (21% v 7%). Most polled Portland residents understood the proper function and positioning of head restraints. This discrepancy between actual practice and understanding should be addressed with public education and manufacturer design changes.
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