Approximately 80 countries now belong to the International Sumo Federation. Thus, people from many regions of the world have the opportunity to experience the emotionally charged atmosphere of sumo. Women's sumo has also been established, and the first World Women's Sumo Championships were held in Aomori, Japan, in 2001. Thus, sumo is enjoyed and practiced by many people and has recently grown to become a worldwide sport.In recent years, increasing participation in sumo has unfortunately resulted in a higher incidence of injuries in sumo wrestling. In professional sumo wrestling in Japan, one sixth of wrestlers were recently defaulted in a championship because of their injuries. One such injury is spinal cord injury, sometimes catastrophically resulting in quadriplegia or paraplegia. In sumo, dislocations of the spine and spinal cord injuries are rare. We have witnessed, however, a case of dislocation of the lower cervical spine and cervical spinal cord injury in a sumo wrestler. We report this case, including details of how the injury occurred and the implications in relation to the rules provided by the Japan Sumo Association.
CASE REPORTA 19-year-old collegiate sumo wrestler, 166 cm tall and weighing 78 kg, had been practicing sumo for 10 years. During an intercollegiate sumo championship on October 31, 1999, he competed with an opponent whose weight was 120 kg. Therefore, the sumo wrestlers in this match had a discrepancy in weight. It was his third fight of the day. From the initial charge, his opponent pushed him, and he escaped by going around the dohyo, or sumo ring. Then, they stopped in the center of the dohyo, and he got under the body of his opponent, as shown in Figure 1. Unfortunately, his position was not ideal. The back of his head was situated on the abdomen of his opponent (Figure 1). After that, his opponent forced him to step outside the dohyo by fixing the back of his head. He had fallen down near the corner of the dohyo, thereby forcing the hyperflexion of his cervical spine (Figure 2).One of the authors (YN), who was a medical doctor for the championship, examined him on the dohyo. He was conscious, his respiration was good, and the mobility of his upper extremities was normal, but his lower extremities were paralyzed. We supposed that he had motor loss below Th2. He had sensory loss below Th4. As cervical spinal cord injury was suspected, his cervical spine was fixed, a few collegiate sumo wrestlers immobilized his body, and he was carefully carried off under the dohyo on the instruction of the medical doctor and taken immediately by ambulance to a hospital.