Synonyms:—Lockjaw; trismus.

Definition:—An acute infectious disease, characterized by tonic spasm of the muscles, first of the jaw and neck; later of the trunk and limbs.

Etiology:—The disease is caused by the development of a specific organism, the bacillus of tetanus, which is introduced usually through a puncture or abrasion of the skin.

Microscopically the bacillus appears as a short, rod-like body with one enlarged end, the whole shaped like a drumstick. It is anaerobic and is capable of producing a toxin which is highly poisonous in character. The disease prevails in temperate as well as in tropical climates. It is common in early summer months and seldom occurs after the month of October. The germ prevails in garden soils and especially around barns and in manure heaps where animal excreta are in process of decomposition, and is of very common occurrence in horses. It develops in wounds, most frequently those of the feet and hands, or punctures by rusty nails and by steel instruments, which are soon closed and not drained. A prick of a pin, a scratch or an abrasion so small as to entirely escape observation, may serve as the point of introduction of the germ. It is also introduced through abrasions of the mucous membranes of the mouth. Open or incised wounds, with free hemorrhage and subsequent free drainage are not so apt to become infected. The toy pistol, which explodes and forces fragments of the percussion cap under the skin, has probably produced more deaths from this disease within the past fifteen years than any other single cause. It has followed the use of contaminated virus in vaccination in several marked cases within the past five years.

The disease attacks new-born infants (tetanus neonatorum), especially in hot climates. It is at times epidemic in hospitals and in camps of laborers. It occurs most frequently among men and barefooted boys. It is common to workers of the soil, gardeners, laborers and to those who work around barns and stables. So-called cases of idiopathic tetanus occur from unknown cause, usually during thte progress of other disease. It may occur during previous good health from sleeping on the damp ground and from wearing wet clothes and exposure to cold.

Symptomatology:—The period of incubation is of variable length, from a few days to several weeks. In idiopathic cases it may occur in two or three days. In trismus neonatorum before the fifth day. There is malaise, languor and headache, during which stiffness of the jaw—lockjaw— occurs, with difficulty in the mastication of food, and soon stiffness of the muscles of the neck and difficulty in swallowing. The muscles of the face become fixed, giving the face a peculiar expression, known as the risus sardonicus. This peculiar expression may be observed before the patient has noticed that his jaws were stiff. Quickly following, rigidity of the muscles of the back occurs, and the spine is slowly bent backward, producing opisthotonus. Very occasionally the body is bent to one side, or contracture of the abdominal muscles bends the body forward. The legs become extended and fixed, but the arms and hands are the last to be affected. The rigidity in all the muscles is permanent, but convulsive seizures may occur, which cause agonizing pain, great difficulty of breathing and cyanosis. Spasm of the diaphragm is a most painful and serious complication. There is some slight elevation of temperature, usually, and in exceptional cases it increases suddenly to an extreme height, perhaps 110° F., from probably paralysis of the heat centers, the pulse becomes rapid, quick, hard, especially during spasm, and ultimately feeble and irregular from exhaustion. Reflex irritability is increased. Profuse perspiration is common, but defecation and urination may be impossible, or they may be involuntary from muscular contraction. The mind remains clear and consciousness is usually retained unto the end.

There are cases of tetanus classed as chronic in which the muscular rigidity is the only symptom at first, and this increases very slowly, to a given point, when it no longer advances for a time, or it may recede and the patient recover spontaneously, or there may be an improvement in the symptoms with a relapse and a recurrence of the condition of spasm. This may be severe and painful for a time. It may involve only the masseter muscles or the muscles of the neck and may interfere slightly with deglutition.

Diagnosis:—The rigidity or fixedness of the jaw, due to the spasm which is described by the patient as "stiffness" of the masseter muscles is usually the first conspicuous symptom, and is diagnostic. No other disease exhibits this peculiar characteristic. Tetany, a disease of childhood, has more or less permanent rigidity of the muscles of the hands and feet. This sometimes affects the larynx. It has distinct remissions, however, and does not affect the masseters and is seldom a serious disorder. Hydrophobia has usually an unmistakable previous history. The constitutional symptoms are much more severe, and permanent contracture or opisthotonos is absent.

In strychnine poisoning the spasms occur with no premonition very soon after a poisonous dose of the agent is taken. They are violent and clonic in character, involving the muscles of the extremities and of the spine, and they do not affect the masseter muscles early. The period of intermission between the spasms is complete in strychnine and become shorter with increased length of spasm until death, which is delayed only a few hours at the longest. In tetanus there is no intermission, only remission, and that not pronounced. There is rather slow involvement of the muscular structure for two to five days in acute cases from the masseters downward until almost the entire muscular structure of the body is in a state of contracture. Hysteria presents some symptoms that simulate tetanus, but they occur only in women of the neurotic type and are usually accompanied with spasmodic laughter and crying, without change of pulse or temperature. They are readily distinguished.

Prognosis:—The mortality from tetanus is from seventy-five to eighty-five per cent in acute and severe cases, in adults, and from fifty to sixty per cent in cases of slow development. In children the disease is usually fatal. Only a small percentage recover.

Death may occur on the second day in the more acute cases, or life may be prolonged in agony until the fifth or sixth. In the chronic cases the spasms may slowly increase for weeks and the patient die from inanition.

Treatment:—If this disease is anticipated all wounds should be freely opened, thoroughly cauterized, but with a minimum of injury to the tissues that are intact, and the vyounds should be disinfected or thoroughly irrigated with normal salt solution. They should be kept open, and should be made to heal by granulation from the bottom of the wound outward. If the spasm occurs before the disease is anticipated irritation and sensitiveness will point to the wound where the infection was introduced. It may have healed naturally. It should be opened widely and any foreign particles searched for. Scars or cicatrices should be incised or entirely removed and the wound thoroughly irrigated and kept open.

The care of the patient and the treatment may mitigate the severity of the disorder, and must lessen the pain. The patient must be kept secluded and quiet, and be attended by a strong, self-reliant and experienced nurse. Nutrition must be forced persistently, and if necessary the food should be predigested. As soon as swallowing becomes difficult the food must be introduced per rectum. Medicines have not as yet exercised any specific influence. In 1884 this author advised the students of the Chicago Veterinary College to inject hypodermically in horses afflicted with tetanus, dram doses of a good fluid extract of the green root of gelsemium sempervirens. This proved to be so much more satisfactory in its results than any previous treatment, that it has since come into almost general use with veterinarians.

It has not been so freely used in human patients but good results from such a course have been observed. Specific gelsemium is the best form for hypodermic use. It may be used in conjunction with passiflora in full doses to the limit of its physiologic influence as the patient can endure it.

Chloral and the bromids exercise a soothing influence upon the patient and in part control the spasms. One physician opened the infected wound widely and filled it with a dram of powdered chloral, and with the internal administration of the remedy he claimed to have controlled the disease satisfactorily. Chloroform inhalations are advisable in extreme pain and spasm. The remedy exercises no curative influence. The Bacelli method of carbolic acid injections has been used by Stevenson and others in tetanus with good results. Three cases treated by Stevenson in this manner all recovered. The wound was opened freely and the agent was injected into all the tissues. A two per cent solution of carbolic acid was used hypodermicaily in twenty minim doses, every two or three hours. This dose may be increased until by the third day twice or even three times the above amount is used. When the tetanic symptoms abate the dose can be slowly reduced. The system is remarkably tolerant of carbolic acid in this disease. Morphin may be used as needed and chloroform inhalations may be administered during the continuance of this remedy with better results than either alone.

We have excellent reports from the use of echinacea in tetanus. There is a record of nearly forty cases in which, with the usual preliminary treatment, this agent was given in from one-half to one dram doses every two hours. It was also injected into the tissues surrounding the infected wound, and the wound was dressed with gauze saturated with the remedy. I feel confident that future observation will prove it to be superior to any other remedy for internal use.

The use of a tetanus antitoxin is now authorized. Of 96 cases treated with Behring's serum, after symptoms of the disease had appeared, there was a mortality of thirty-eight per cent only. Other and more extended reports give a mortality of from forty to forty-two per cent. In cases where the disease was anticipated and the remedy administered as a prophylactic measure the results were more satisfactory. In especially severe cases it is advised that the antitoxin be injected directly into the spinal canal, having previously withdrawn an equal quantity of the fluid. To us this seems an unjustifiably severe and dangerous procedure, with so little testimony as yet in favor of a curative result.

The Eclectic Practice of Medicine with especial reference to the Treatment of Disease, 1910, was written by Finley Ellingwood, M.D.