Background and purpose: The incidence of electric scooter (e-scooter) injuries has increased drastically in numerous countries after widespread availability of shared e-scooters. Most publications on e-scooter injuries focus on a specific category of injuries. The economic impact on society from a broader perspective has not been studied. Patients and methods: We performed a retrospective cohort study including all e-scooter-related injuries presented in the three adult emergency departments in Helsinki in 2021. We collected the patient data from the university hospital information system. Injury severity was evaluated based on the abbreviated injury score. Cost of the hospital treatment was analyzed based on our hospital district's service price listing. In addition, we recorded the total amount of sick leave days and estimated their economic impact. Results: In total, 446 e-scooter injuries were identified and taken into the analysis (434 affecting riders and 12 non-riders). The median age of the patients was 26 (IQR 22-33) and 59 % were male. 257 (58 %) of the of the injuries were minor, whereas 155 (35 %) were moderate, 30 (7 %) serious, 3 (0.7 %) severe, and one (0.2 %) critical. Furthermore, 220 (49 %) of the patients sustained head injuries. A major spike in accident incidence was seen during weekend (Friday to Sunday) nights, which was accompanied by a proportional increase in patients with alcohol intoxication. Including both the costs of the hospital care and absence from work, the approximated total cost of e-scooter injuries was 1.7 million euros, with a median cost of a single accident being 1148 euros (IQR 399-4263). Interpretation: Comprehensive preventive measures must be conducted to decrease the incidence of e-scooter injuries. The usage of helmets should be strongly encouraged in order to prevent severe head injuries. The night-time bans during weekends and speed-limits on e-scooters appear to be justifiable.

The authors have declared no competing interest.

This study has not receive any external funding

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

IRB of Helsinki University Hospital gave ethical approval for this work.

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The datasets generated and analysed during the current study are not publicly available due potential other publications utilizing the data but are available from the corresponding author on reasonable request.