CHAPTER IV.. Diseases of Muscles and Tendons.

DISEASES OF MUSCLES AND TENDONS.

RUPTURE OF THE EXTERNAL ISCHIO-TIBIAL MUSCLE (BICEPS FEMORIS).

The biceps femoris muscle extends from the superior spinous process of the sacrum to the region of the patella and the external surface of the thigh. Above, it is inserted into the sacrum and the posterior margin of the ischium, below into the supero-external surface of the tibia. It completely covers the coxo-femoral articulation, and its passage over the summit of the trochanter is lubricated by a serous bursa. The whole of its anterior margin is connected with the fascia lata by an aponeurotic expansion. From varying causes this aponeurotic layer may become fissured; during the backward and forward movements of the limb the summit of the trochanter may enter the fissure and become fixed there by the tension and resistance of neighbouring tissues. This accident has been described as “displacement or rupture of the biceps femoris muscle.”

According to Cruzel, fixation of the biceps femoris may occur, in very thin animals, without rupture of the musculo-aponeurotic layer, the process being then simply confined to stretching of the aponeurotic layer over the summit of the trochanter. Under such circumstances the musculo-aponeurotic layer presents a cup-like depression, into which the summit of the trochanter fits, and thus effectually prevents movement of the muscle.

Whether the accident is due to an actual fissure, or only to stretching of the aponeurosis, the symptoms are the same.

=Causes.= The principal predisposing causes are thin condition and malformation of the limbs (turning outward of the hind toes).

The accident may occasionally be caused by a slip backwards, or by extreme efforts in draught when ascending hills.

=Symptoms.= Immediately the accident occurs the limb becomes fixed in a position of maximal extension. The trochanter being caught, the femur can no longer be flexed, and the lower joints are also fixed in such a way that the limb can only be moved as a whole. The claws are dragged along the ground, and the affected limb, which can never be completely advanced, is brought forward with a mowing movement.

On local examination, the trochanter appears to be very prominent, and situated directly above a rigid cord which extends parallel with the anterior margin of the affected muscle.

If the accident consists merely in the formation of a depression in the muscle, in which the summit of the trochanter is fixed, and if there is no fissuring, the muscle and the femur are certainly immobilised, but the limb can be moved to a certain extent, the “mowing” movement is less marked, and there is no well-defined rigid cord along the anterior margin of the muscle.

=Diagnosis.= The condition can only be confused with luxation of the patella; but manual examination of the affected parts revealing the presence of a rigid cord below the trochanter at once removes any doubt.

=Prognosis.= The prognosis is only grave in working animals. Moreover, the accident is now much rarer than formerly, if only because animals are better looked after and better fed.

=Treatment.= If the accident results simply from the formation of a depression in the musculo-aponeurotic layer which replaces the muscle at the point where it passes over the trochanter, there is nothing to be done. Reduction will occur spontaneously, and entire liberty of action will be regained. Cruzel states that it is sometimes sufficient to force the animal to move down a slope, in order to withdraw the trochanter from the depression in which it has been lodged, and to restore its normal mobility.

Rest and good feeding favour the deposition of fat, and soon alter the conditions responsible for the accident; the muscles of the quarter become surrounded with fat, the external ischio-tibial muscle (biceps femoris) is thrust outwards on account of its superficial position, and then cannot be ruptured by the summit of the trochanter. If, on the other hand, the musculo-aponeurotic layer is fissured and the summit of the trochanter firmly fixed in the opening, operation becomes necessary. This consists in incising the anterior margin of the muscle over the afore-mentioned rigid cord. The margins of the wound retract, the tension of the cord is diminished, the trochanter released, and the normal play of the limb restored.

Numerous methods of operation have been described and a number of special instruments invented. The earlier methods consisted in simple subcutaneous section of the rigid cord formed by the musculo-aponeurotic layer and the muscle. Subcutaneous section is carried out exactly like tenotomy, using straight and curved tenotomes. The seat of operation is about three inches below the summit of the trochanter. In the absence of tenotomes, section may be performed with a bistoury introduced from below the muscle by means of a grooved director, which has been inserted through a cutaneous puncture made at the point indicated over the anterior margin of the prominent cord.

In better nourished subjects, in which this cord is less prominent, the operator may, to ensure greater accuracy, make a vertical incision an inch or two in length at the point selected over the anterior margin of the muscle, isolate this muscle by means of the director, and afterwards perform the section. Considerable hæmorrhage occasionally follows division of some small muscular vessel, but is of no consequence unless the wound has been infected.

RUPTURE OF THE FLEXOR METATARSI.

The rupture of this tendon-muscle is exceptional, and, according to the description given by Furlanetto, is attended by the same symptoms as in the horse—i.e., flexion of the stifle joint is not accompanied by flexion of the hock or of the metatarsus on the tibia. The cannon bone hangs vertically when the limb is moved.

Recovery follows prolonged rest.

Wounds and sections of tendons in the region of the cannon bone, sections of the tendo-Achillis, etc., have been seen and described. All such injuries may heal under antiseptic treatment and after aseptic suture of the divided ends, provided the sutures and dressings are applied immediately. If, on the other hand, suppuration, infection, necrosis of tendons, synovitis or arthritis occur as complications, such injuries become extremely serious, and from an economic standpoint render it better to sacrifice the animal rather than attempt treatment.

Strains of tendons and tendinitis occur in the front limbs of oxen, particularly of those used in carts. The chief indications are swelling in the region of the cannon bone and fetlock, uneven contour of the flexor tendons, sensibility on pressure, and lameness of varying intensity.

=Treatment= consists in continuous cold irrigation, massage, the application of a blister or even of the actual cautery. As a rule, however, it is better to rest and fatten the animal.

A frequent complication of such injuries of tendons consists in knuckling over at the fetlock.

PARASITIC DISEASES OF MUSCLES.

INFECTION WITH CYSTICERCI.

Infection of the connective and muscular tissues with cysticerci results from the entry into the body of embryos of Tænia solium and Tænia saginata of man. It occurs in man and almost all animals, but is only of grave clinical importance in the pig and ox.

The following table shows the chief cystic (cestode) parasites of animals, though the cysts are not always confined to muscular structures:—

┌─────────────────────────┬───────────────────────────────────────────┐ │ Adult. │ Larva. │ ├───────────────────┬─────┼───────────────────────┬───────────────────┤ │ Name. │Host.│ Name. │ Host. │ ├───────────────────┼─────┼───────────────────────┼───────────────────┤ │Tænia saginata │Man │Cysticercus bovis │Cattle. │ │Tænia solium │Man │Cysticercus cellulosæ│Swine and man. │ │Tænia marginata │Dogs │Cysticercus │Cattle, sheep, and │ │ │ │ tenuicollis │ swine. │ │Tænia cœnurus │Dogs │Cœnurus cerebralis │Cattle and sheep. │ │Tænia │Dogs │Echinococcus │Cattle, sheep, │ │ echinococcus │ │ polymorphus │ swine, man, etc. │ └───────────────────┴─────┴───────────────────────┴───────────────────┘

CYSTICERCUS DISEASE OF THE PIG.

This disease of the pig is due to Cysticercus cellulosæ, the cystic form of the Tænia solium or Tænia armata of man. As a disease of the pig it has been recognised from the most ancient times, and is stated to be the cause of Moses and Mohammed having prohibited the consumption of pork by their disciples. In the Middle Ages it formed the subject of legislation. It was, however, only when the investigations of Van Beneden and Kuchenmeister had completed those of the zoologists of the seventeenth and eighteenth centuries that the evolution of tæniæ became well known and the importance of the cystic phase clearly established.

=Causation.= The cause of cysticercus disease in the pig may be summed up in one phrase—viz., ingestion of eggs or embryos of Tænia solium.

Young animals alone seem to contract the disease. After the age of eight to ten months they appear almost entirely proof against it.

It is very rare in animals reared in confinement, but is relatively common in those roaming at liberty; because they are much more likely to discover human excrement and the embryos of tænia. The eggs having been swallowed, the six-hooked embryos are set at liberty in the intestine, perforate the tissues, enter the vessels, and are carried by the blood into all parts of the body. Those alone develop well which reach the interstitial and intermuscular connective tissue. The others in the viscera usually disappear. Their presence in the depths of the muscles produces slight general disturbance and signs of local irritation, due to the development of the cyst itself. At the end of a month the little vesicle is large enough to be visible to the naked eye; in forty to forty-five days it is as large as a mustard seed, and in two months as a grain of barley. Its commonest seats are the abdominal muscles, muscular portions of the diaphragm, the psoas, tongue, heart, the muscles of mastication, intercostal and cervical muscles, the adductors of the hind legs, and the pectorals.

=Symptoms.= The symptoms of invasion are so little marked as usually to pass undetected. Occasionally, when large quantities have been ingested, signs of enteritis may occur, but these are generally ascribed to some entirely different cause. In some cases there is difficulty in moving, and the grunt may be altered.

Certain authors declare that the thorax is depressed between the front limbs, but this symptom is of no particular value, and is also common to osseous cachexia and rachitis. Paralysis of the tongue and of the lower jaw is of greater importance. In exceptional cases, where the cysticerci are very numerous and penetrate the brain, signs of encephalitis, vertigo, and turning sickness (gid, sturdy) may be produced. These signs, however, disappear, and the cysticerci undergo atrophy. Interference with movement may give rise to suspicion when the toes of the fore and hind limbs are dragged along the ground, and thus become worn. This peculiarity is due to the presence of cysts in the muscles of the limbs, but it occurs in an almost identical form in osseous cachexia.

One symptom alone is pathognomonic, and it appears only at a very late stage—viz., the presence of cysts under the thin mucous membranes which are accessible to examination, such as those of the tongue and eye.

Visual examination then reveals beneath these mucous membranes the presence of little greyish-white, semi-transparent grains the size of a grain of barley, or even larger. Unfortunately, in an animal so difficult to handle as the pig, this visual examination is decidedly troublesome, and is usually replaced by palpation. In many instances the disease does not attract attention during the patient’s life, and is only discovered on slaughter in consequence of the lesions by which it is characterised.

=Diagnosis.= As the characteristic lesions of cysticercus disease are to be found in the depths of the muscular and connective tissues, and as the external symptoms may be regarded as of doubtful significance, the diagnosis can only be confirmed during life by manual examination of the tongue. This examination of the tongue has been practised since the earliest times. Aristophanes even speaks of it, and in the Middle Ages it was performed under sworn guarantees. The regulations concerning the inspection of meat have finally led to the suppression of this calling.

In this method of examining the tongue, the operator commences by throwing the animal on its side, usually on the right side, and holding it in this position by placing his left knee on its neck. He then passes a thick stick between the jaws and behind the tusks, opens the mouth obliquely, raising the upper jaw by manipulating the stick. Finally he fixes one end of this last by placing his foot upon it, and holds the other extremity by slipping it under his left arm. In this position he is able to grasp the free end of the tongue and by digital palpation to examine the tongue itself, the gums, the free portions of the frænum linguæ, etc.

If he discovers cysts, the diagnosis is confirmed, but failure to do so by no means disposes of the possibility of infection. Railliet declares that about one animal in four or five shows no cysts beneath the tongue, and, moreover, fraud is possible in this connection, it being quite possible to prick the little cysts with a needle so that the liquid contents escape, and examination gives no positive result. For these reasons intra-vitam examination alone is now discounted, and the chief reliance is placed on post-mortem search.

=Prognosis.= The prognosis is very grave, not on account of danger to the lives of the infected, but because infected meat may be offered for human consumption. Should such meat, in an insufficiently cooked condition, be eaten by man, its ingestion is followed by the development of Tænia solium. If cooking were always perfect it would destroy the cysticerci, but the uncertainty in this respect should prevent such meat being consumed. The cysticerci are killed at a temperature of 125° to 130° Fahr.

=Lesions.= The lesions are represented by cysts alone—i.e., by semi-transparent bladders, each of which contains a scolex or head armed with four suckers and a double crown of hooks. The little bladders are most commonly found in the muscles, lodged in the interfascicular tissue, which they slightly irritate.

The number present varies extremely, depending on the intensity of infestation and the number of eggs swallowed. Whilst in some cases difficult to discover, in others they are so numerous that the tissues appear strewn with them.

They are commonest in the muscles of the tongue, neck, and shoulders, in the intercostal and psoas muscles, and in those of the quarter.

The viscera—viz., the liver, kidneys, heart, lungs, etc.—are less commonly infested, and in these organs the cysts degenerate very rapidly. In animals which have been infested for a long time, the cysts may even have undergone caseo-calcareous degeneration, the liquid being absorbed and the lesions presenting the appearance of little oblong firm nodules.

On cutting through masses of muscle the vesicles protrude from between the bundles.

In young animals, infestation with cysticerci causes wasting and ill-health; subsequently the patients improve in appearance, later on fatten, and gain marketable condition.

Of the carcases examined in Prussian slaughter-houses between 1876–82, one in every 305 was found infested; between 1885–93, one in every 537.

=Treatment.= There is no curative treatment. Only preventive measures are of value. These are confined to rendering it impossible for animals to ingest eggs of the Tænia solium.

Cysticercus disease is rare in the north, centre, and east of France, and in districts where animals are reared in confinement. It is commoner where pigs are at liberty, such as Limousin, Auvergne, and Perigord. It is frequent in North Germany, where the custom of eating half-cooked meat contributes to the propagation of Tænia solium. It is also frequent it Italy.

BEEF MEASLES.

=Causation.= The disease of beef measles is due to the penetration into the connective and muscular tissues of embryos of the Tænia saginata, or unarmed tænia of man.

This disease, unlike that of the pig, has only been recognised within comparatively recent times, and only after Weisse’s experiments (St. Petersburg, 1841) on feeding with raw flesh was attention drawn to it, although as early as 1782 the Tænia saginata had been described by Goëze.

Measles in the ox is rarely seen in France, but is common in North and East Africa. Alix has found it in Tunis, Dupuys and Monod in Senegal, and it is common in the south of Algeria. The disease is due simply to oxen swallowing eggs or embryos of the unarmed tænia, a fact which explains the frequency of the disease in places where the inhabitants are of nomad habits, and consequently disregard the most elementary rules of public and general hygiene.

Furthermore, cattle in the Sahara, in Senegal and in the Indies, have a very marked habit of eating ordure, and as no attempts are made to prevent it, the risk to these animals is greatly increased.

As in the pig, the embryos which reach the stomach and intestine penetrate into the circulatory system, and are thereby distributed throughout the entire organism.

The development of the cysticercus is complete in forty days, and if swallowed by man in infected meat after this period it again gives rise to the Tænia saginata.

The age of the animals seems of less importance than in the case of the pig, for Ostertag and Morot have seen cases of beef measles in animals of ten years old.

=Symptoms.= The symptoms are still less marked than in the pig, and in ordinary cases of infection always escape observation. Stiles, however, gives the following account of a case experimentally infected:—

“Symptoms. Four days after feeding segments of T. saginata to a healthy three-months-old calf, the patient showed a higher temperature (the normal temperature was 39·2° C.). The calf ate but little on that day, showed an accelerated pulse, swollen belly, staring coat, and upon pressure on the sides showed signs of pain. The next day the animal was more lively, ate a little, and for nine days later did not show any special symptoms except pain on pressure of the abdominal walls, and a slight fever. Nine days after the infection the temperature was 40·7° C., pulse 86, respiration 22; the calf laid down most of the time, lost its appetite almost entirely, and groaned considerably. When driven it showed a stiff gait and evident pain in the side. The fever increased gradually, and with it the feebleness and low-spiritedness of the calf, which now retained a recumbent position most of the time, being scarcely able to rise without aid, and eating only mash with ground corn. Diarrhœa commenced, the temperature fell gradually, and on the twenty-third day the animal died. The temperature had fallen to 38·2° C. During the last few days the calf was unable to rise; in fact, it could scarcely raise its head to lick the mash placed before it. Pulse was reduced by ten beats. On the last day the heart-beats were very much slower, yet firm, and could be plainly felt. Several days before death the breathing was laboured, and on the last day there was extreme dyspnœa.”

=Diagnosis.= In forming a diagnosis we meet with the same difficulty as in the case of the pig. It is always easy to examine the tongue; but when visible lesions are absent diagnosis in the case of the ox remains doubtful and problematical even more than in the pig.

In the carcase, diagnosis is much easier. The cysts are sought for, as in the pig, by making sections of muscle, those usually selected being the pterygoid, cervical, cardiac, and psoas muscles, and those of the quarters.

=Prognosis.= The prognosis is grave, not indeed for the infected animals, which seem little injured by the parasite, but for human beings, who run the risk of contracting Tænia inermis by eating insufficiently-cooked meat.

A temperature of 115° to 120° Fahr. destroys the cysticerci, but in roast meats the central temperature of the mass always remains below this figure.

Salting for fifteen to twenty days destroys the vitality of the parasite.

=Lesions.= The lesions are confined to the presence of the cyst and of two little zones of chronic inflammation immediately surrounding it. Unless heavily infested the subjects fatten just as well as others.

The vesicles are semi-transparent, ³⁄₁₆ inch to ¼ inch in length, slightly ovoid in form, and contain a tænia head with four suckers, but without hooks.

In seven to eight months the cysts undergo degeneration, the liquid is absorbed, and calcium salts are deposited throughout the mass. The lesions which remain have, in the ox, the appearance of interstitial disseminated tuberculosis.

There is no curative treatment. The infested animal recovers spontaneously with the lapse of time, for the cysticerci undergo degenerative processes, but the flesh of such animals is of little commercial value.

From a preventive standpoint we can only hope to improve matters by a gradual and progressive change in social and public hygienic conditions.

When the life of the nomad shall have been entirely replaced by that of the highly-civilised European and private hygienic precautions have rendered it impossible for animals to obtain access to segments or eggs of the Tænia saginata, beef measles will disappear.

At present, in the countries where the disease is common, one experiences a feeling of astonishment that it is not far more frequent; for experiment has shown that a person infected with one unarmed tapeworm expels with the fæces an average of four hundred proglottides per month, each proglottis or segment of the worm containing about 30,000 eggs, each of which is capable of developing into a tapeworm.

Beef measles is rather common in Germany, but rare in France, Switzerland, and Italy.

TRICHINIASIS—TRICHINOSIS.

Trichinosis is a disease caused by the entrance into the body of the Trichina spiralis. This parasite is swallowed in the larval form, and undergoes sexual changes in the intestine, at first producing intestinal trichinosis, which represents the first phase in the development of the disease.

The trichinæ breed rapidly. The embryos penetrate into or are directly deposited in the blood-vessels, which convey them to all parts of the body, thus setting up the second phase of the disease, known as muscular trichinosis.

Trichinosis as a disease has long been recognised. Peacock in 1828 and J. Hilton in 1832 mentioned the existence of the cysts of trichinæ; Owen in 1835 gave the name of Trichina spiralis to the parasites contained in the cysts. Trichinosis being common in Germany at that time, Virchow and Leuckart undertook its investigation, but mistook other nematodes of the intestine for the Trichina spiralis. In 1847 Leydy recognised that trichinosis occurred in American pigs.

In 1860 Zenker found muscular and intestinal trichinosis on post-mortem examination of a girl who had been suspected of suffering from typhoid fever, and a carefully conducted inquiry revealed the fact that this girl had some time previously eaten a quantity of raw ham. Virchow and Leuckart returned to their investigations, and the life history of the parasite soon became definitely known.

=Causation.= Trichinosis is capable of attacking all mammifers without exception, from a man to a mouse; and most animals which can be made the subjects of experiment contract the disease in varying degrees.

The intestinal form is seen in birds, but the muscles do not become infested by the embryos.

Cold-blooded animals are proof against the disease.

After the ingestion of meat containing cysts of the parasite, the processes of gastric and intestinal digestion set the larvæ at liberty. These larvæ become sexual at the end of four to five days, and the females, which are usually twice as numerous as the males, begin laying eggs from the sixth day, continuing for a month to six weeks. Each female lays approximately from 10,000 to 15,000 eggs. The embryos perforate the intestinal walls, pass into the circulation, and are hurried into all parts of the system. This period of infestation constitutes the first phase of the disease.

Askanazy, in 1896, suggested that it was not the embryos which perforated the intestinal walls and thus reached the blood-vessels, but the fertilised female trichinæ themselves, which entered the terminal chyle vessels and laid their eggs directly within them.

This observation is of great interest, for it contradicts the view held by Leuckart and proves that treatment is useless even in the first phase.

The males are about ¹⁄₁₆ inch in length, the females ⅛ inch to ⁵⁄₃₂ inch, and are ovoviviparous.

=Symptoms.= The symptoms lack precise character, even when the disease is known to be developing, and moreover they have only been carefully observed in experimental cases. As soon as the laying period begins, signs of intestinal disturbance may be observed, possibly due to embryos perforating the intestinal walls (if we accept Leuckart’s view), or, according to Askanazy, to adult females penetrating the chyle vessels and disturbing intestinal absorption.

These symptoms are only appreciable in cases of “massive” infestation. If slight, the disturbance passes unperceived. In severe cases the symptoms consist of diarrhœa, loss of appetite, grinding of the teeth, abdominal pain in the form of dull colic, and sometimes irritation of the peritoneum. The embryos carried by the circulation then escape into the tissues and, like the cysticerci, become encysted, preferably in the muscles, in the interfascicular connective tissue towards the ends of the bundles. Each (asexual) parasite plays the part of a foreign body, causing infiltration of serum and exudation of leucocytes in its neighbourhood, and soon becoming encysted in the interior of a little ovoid space surrounded by a fibro-fatty wall. Fat granules accumulate at each end of the cyst.

The parasite, which at first appeared straight, soon assumes a bent form, then that of a figure “6,” then of a figure “3,” and preserves a latent vitality throughout the entire period of encystment. These cysts are of very small dimensions, invisible to the naked eye, and their discovery necessitates the use of the microscope. They are about ¹⁄₆₄th inch in length and ¹⁄₁₂₀th inch in width. Very frequently two or three cysts may be found arranged in line, presenting the appearance of beads on a string: more rarely two parasites may be found in one cyst; exceptionally, as many as six or seven. The appearance of “beads on a string” is due to the fact that the parasites follow the interfascicular capillaries.

In animals which are kept for a long time and fattened the cyst walls undergo fatty infiltration. The change is commonest in pigs. In the same way calcareous infiltration sometimes occurs, but only when the parasites have lost their vitality. This calcareous degeneration consists in the deposit of carbonate and phosphate of lime in the walls of the cyst; it never begins before the seventh or eighth month after infestation, and is sometimes much longer delayed.

No man or animal ever becomes infested except by the ingestion of meat or drink containing larval trichinæ. The pig and small rodents are most frequently attacked. Man contracts trichinosis by eating insufficiently cooked infected pork. The fact that small rodents, particularly rats, eat the bodies of their kind explains the persistence of trichinosis in certain regions. Pigs roaming at large, and thus liable to find and eat the dead bodies of such rodents, may contract trichinosis in this way or from eating ordure.

For some weeks after the larvæ have penetrated the muscular tissues the animals show stiffness of the limbs, difficulty in moving, and in mastication, etc., but these troubles disappear in a short time.

The above facts explain why trichinosis in the pig is almost unknown in France, Italy, and Spain. It is commoner in Germany and in certain States of Europe, such as Holland and Russia, although investigations had previously shown that in Paris about 7 per cent. of the sewer rats were sufferers from trichinosis and that in Germany the percentage rose as high as 15 to 20. In Chicago and Cincinnati, U.S.A., the proportion of rats suffering from trichinosis has been as high as 50 to 70 per cent., and as in some of the Northern States pigs were bred in complete freedom, it follows that at one time very large numbers of American pigs must have suffered from trichinosis.

In consequence of sanitary precautions this proportion has since greatly diminished.

=Diagnosis.= During the animal’s life diagnosis is a difficult matter, though, on the other hand, simple microscopic examination of suspected meat is sufficient at once to settle the question. In dealing with the living animal, however, it is necessary, as in examining suspected meat, to obtain a fragment of muscle in order to submit it to microscopic examination. This fragment can be obtained by the method known as “harpoonage,”—a trocar provided with a cutting hook, or a trocar the canula of which has a sharp-edged opening near its end, being thrust into the muscle. On removing the trocar the elasticity of the tissues causes a fragment to project into the opening in the canula, and on withdrawing the latter a fragment sufficient for examination is obtained. One may proceed in the same way by harpoonage when examining large masses of suspected meat the surface of which reveals no lesion.

The specimen having been obtained, a few fragments of the muscular fasciculi are crushed between two glasses and examined with a low power.

The trichinæ will be found towards the ends of the muscle near the region of the tendons; few or none exist in the fat. These parasites are most readily discovered in the diaphragm, in the muscles of the shoulders and quarters, and in the psoas muscles.

=Prognosis.= The prognosis is relatively favourable so long as infestation is only moderate. But it is very grave from the point of view of public hygiene, on account of the possibility of persons becoming infected by eating the diseased meat.

=Treatment.= There is no curative treatment. Formerly it was believed that, provided the condition were early diagnosed, the intestinal form might possibly be cured by administering purgatives and vermifuges so as to prevent the embryos penetrating the system.

After Askanazy’s discoveries this view had to be abandoned, and the practitioner is necessarily powerless in dealing with the muscular form. Time alone effects improvement and a relative cure by causing caseo-calcareous degeneration of the cysts. With a prophylactic object, every precaution should be taken to prevent the possibility of pigs being contaminated. This question particularly interests America, because of the extreme prevalency of pig trichinosis there.

From the point of view of public hygiene all infected meat should be seized and destroyed, despite the fact that perfect cooking destroys the vitality of the parasites, which perish at 120° Fahr.

Ordinary salting but slightly affects their vitality, which explains why from time to time the importation of meat has to be prohibited and why meat should always be scrupulously inspected.