Background and purpose -- COVID-19 lockdowns have affected personal mobility and behavior worldwide. This study compared the number of emergency department (ED) visits due to injuries and typical low-energy fractures in Finland during the COVID-19 lockdown period in spring 2020 to the reference period in 2019. Patients and methods -- The data was collected retrospectively from the electronic patient records of 4 hospitals covering 1/5 of the Finnish population. We included the patients who were admitted to a hospital ED due to any injury during the lockdown period (March 18--May 31, 2020) and the reference period (March 18--May 31, 2019). We compared the differences between the average daily ED admissions in the 2 years using the zero-inflated Poisson regression model. Results -- The overall number of ED visits due to injuries decreased by 16% (mean 134/day vs. 113/day, 95% CI --18 to --13). The number of ED visits due to wrist fractures decreased among women aged over 50 years by 40% (CI --59 to --9). Among women, the number of ED visits due to ankle fractures decreased by 32% (CI --52 to --5). The number of ED visits due to fractures of the upper end of the humerus decreased by 52% (CI --71 to --22) among women. The number of ED visits due to hip fractures increased by 2% (CI --16 to 24). Interpretation -- Restrictions in personal mobility decreased the number of ED visits due to injuries during the pandemic. The effect can mainly be seen as a decreased number of the most typical low-energy fractures among women. In contrast, lockdown restrictions had no effect on the number of hip fractures.