Related Experiment Video
Updated: Mar 27, 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
Repeal of the Michigan helmet law: the evolving clinical impact
Rebecca H Striker1, Alistair J Chapman1, Rachel A Titus1
1Department of Surgery, Michigan State University and Grand Rapids Medical Education Partners, 221 Michigan Street 200A, Grand Rapids, MI 49503, USA.
Background:
Michigan repealed a 35-year mandatory helmet law in April 2012. We examined the impact of this legislation on a level 1 trauma center.
Methods:
A retrospective cohort study comparing the 7-month period before and the 3 motorcycle seasons after the helmet law repeal.
Results:
A total of 345 patients were included in the study. Nonhelmeted riders increased from 7% to 28% after the repeal. Nonhelmeted crash scene fatalities were higher after the repeal (14% vs 68%). The nonhelmeted cohort had significantly higher in-patient mortality (10% vs 3%), injury severity score (19 vs 14.5) and abbreviated injury scale head (2.2 vs 1.3). Non-helmeted riders also had increased alcohol use, intensive care unit length of stay and need for mechanical ventilation. The median hospital cost for the non-helmeted cohort was higher (P < .05).
Conclusions:
The impact of the Michigan helmet law repeal continues to evolve. Three years after this legislative change, we are now observing increased injury severity score, higher in-patient mortality, and worse neurologic injury.
