On January 2, 2023, the nation was shocked by the sudden collapse of Buffalo Bills safety Damar Hamlin. Speculation was rife as to the cause of the incident, with many people suggesting that it was due to commotio cordis. This is a rare event, and one that can be fatal. In this article, we will explain what commotio cordis is, so that you can better understand why it may have been the cause of Hamlin’s collapse. What Is Commotio Cordis?