Introduction: Boxing has been described as both a brutal business and the purest of sports. One of the most controversial aspects of the activity is the knockout. No other sport lists the deliberate production of a state of unconsciousness in an opponent, a concussion, as one of its goals. This study attempted to explain the mechanism of the knockout, as well as that of boxing-related fatalities. Methods: We analyzed 50 professional boxing matches that resulted in knockout or death for the mechanism of the cerebral insult. The bouts were reviewed round by round in an attempt to identify similarities in the causes of cerebral dysfunction.
Results: The mechanism of the knockout differed from that of the fatality. Knockouts almost exclusively resulted from single blows to the side of the head or jaw. In contrast, boxing fatalities resulted from the cumulative trauma of multiple punches, none significant enough to result in immediate knockout. Several common risk factors were discovered in the fighters who suffered fatal injuries. Conclusions: Knockouts, often secondary to single blows to the side of the head, are best explained by the transient distortion of the brain stem. This “kinking” can result in a transient loss of consciousness or motor control. Fatalities, on the other hand, result in the loss of consciousness secondary to bilateral cerebral cortex dysfunction. Boxers who seem to be oblivious to the punishment they are taking and are performing “on automatic” tend to receive an abnormal amount of brain trauma. The results of this study can by extrapolated to shed light on mechanisms of cerebral injury in the general population.