Clostridal myositis and myonecrosis is an acute, rapidly progressive infection of the soft tissues commonly known as “gas gangrene”. the infection is caused by one of several bacteria in the group known as “clostridium”. Clostridium bacteria are “anaerobic”, meaning that they prefer low oxygen concentrations to grow. If clostridium are exposed to high amounts of oxygen, their replication, migration and exotoxin production can be inhibited. This is the rationale for the use of hyperbaric oxygen in the treatment of gas gangrene.