Publisher Summary Tetanus was first recorded in the very earliest medical literature. The most common form of the disease is generalized tetanus, in which the portal of entry is a minor wound in 80% of cases. It usually begins with a characteristic facial trismus. Subsequently, neck stiffness develops and later spreads to the vertebral muscles and to those of the abdomen and limbs. The typical tetanic seizure is characterized by a sudden burst of tonic muscle contraction that causes arching of the back, flexion and adduction of the arms, and extension of the lower extremities. The patient is completely conscious during such episodes and experiences intense pain. Later, autonomic symptoms develop with alterations of blood pressure and of the cardiac rhythm and sweating. Dysphagia may occur and lead to hydrophobia. Spasm of the glottis and larynx may also develop and cause cyanosis and asphyxia if they are not promptly relieved by medical or surgical means. Dysuria or urinary retention may develop. In milder cases, a local form of tetanus develops with rigidity of the group of muscles close to the site of injury. This local tetanus may persist for a considerable time without further developments, or it may proceed to generalized tetanus. Local tetanus is due to dysfunction of interneurons that inhibit the α motor neurons of the affected muscles, without further spread through the central nervous system.