suffered with a cough and had thereby produced a hernia of the lung between the eighth and ninth ribs on the left side and another between the seventh and eighth ribs on the right side at the level of their junction with the cartilages, accompanied by a separation between the seventh rib and its cartilage on the right, and between the eighth and its cartilage on the left; at each of these points the rib was movable with crepitation. Bouisson's and Chas. Bell's cases have been quoted in the volume on Fractures, p. 321. In the remaining case, De Kimpe,' the patient was thrown from his horse, and struck his chest against a milestone; the fifth costal cartilage on the left side was depressed so that the rib overrode it and projected under the skin. The displacement could be corrected by a full inspiration, but recurred on expiration. A tight starch bandage was worn for three weeks, and then union was found to have taken place with a displacement backward of the cartilage equal to about one-third its thickness.

2

The possible sixth case is Monteggia's, a separation of the second and third costal cartilages in a very emaciated man seventy years old, in consequence of a violent attack of coughing. Gurlt says: "Monteggia declares expressly that it was not a fracture of the cartilage but a separation of the epiphysis," by which, of course, is meant a separation at the costo-chondral junction.

The injury is so closely allied to fracture of the cartilages that the reader is referred for other details to Chapter XVIII. of the volume on Fractures.

DISLOCATION OF THE COSTAL CARTILAGES FROM THE STERNUM. (LUXATIO CHONDRO-STERNALIS.)

6

3

Of this injury there are twelve recorded examples: Ravaton, Manzotti, Monteggia, and Bell, quoted by Malgaigne; Cooper, Flagg,* Wolfenstein, Gross, Bennett, Mulvany, and Blodgett, two cases. There are, in addition, one or two cases, elsewhere referred to (see Chap. XIII.), in which separation of the first and second pieces of the sternum has been accompanied by complete separation of the second costal cartilage from the sternum on one or both sides.

In three of the cases (Bell, Cooper, and Blodgett's second) the cause appears to have been traction exerted through the pectoralis major, in swinging dumb-bells, kneading bread, and exercising on parallel bars; and possibly the cause was the same in Blodgett's first case, in which a man while carrying a piano made a violent effort to prevent its fall. In three others the cause was a fall; in the remainder it is unrecorded or obscure.

1 De Kimpe: Gaz. des Hôpitaux, 1852, p. 18.

* Gurlt: Loc. cit., vol. 2, p. 250.

Cooper: Loc. cit., p. 451.

Flagg: Northwestern Med. and Surg. Journal, August, 1871, quoted by Ham

ilton.

Wolfenstein: Allg. Wiener Med. Ztg., 1873, No. 44, quoted by Poinsot.
Gross: Surgery, 6th ed., vol. I., p. 1132.

7 Bennett: Dublin Journal Med. Sc.,

"Mulvany: Lancet, 1882, I. p. 432.

1879, I. p. 441.

Blodgett N. Y. Med. Journ, 1883, vol. 38, p. 34.

The fourth cartilage was displaced singly forward in three cases, forward in combination with the fifth and sixth in two, and backward with the second and third in one; the third singly, the fifth and sixth together, and the fifth, sixth, and seventh together were each displaced forward in one case, and the first and second were together displaced forward and outward once (Blodgett's first). In two cases it is not stated which cartilage was displaced, nor in what direction.

The only autopsy was in Bennett's case. The patient was a woman about fifty-six years old who had been run over by a cart and died a few days later of pleurisy and pneumonia. The third cartilage on the left side was displaced forward, and there was also fracture of the second, third, fourth, and fifth ribs on the same side, and of the second to the ninth ribs on the right side. The perichondrium with the attached ligaments was stripped clean off. The dislocation was reduced by direct pressure and did not recur; it must be remembered, however, in connection with this, that the corresponding rib was broken.

In the single case of backward dislocation (Mulvany) the patient was a boy fifteen years old, who while steering a ship in a heavy storm was thrown violently across the deck by a wave and struck upon the back of his left shoulder against the deck-house. The second, third, and fourth left cartilages were displaced backward behind the sternum, and the sternal end of the right clavicle was dislocated forward. Reduction could be effected by drawing the shoulders backward, but the displacement immediately recurred when the traction ceased. The patient was kept upon his back for eighteen days, and the deformity was then found to have been much diminished. In two months he was again at work.

Usually there has been sharp local pain at the moment of the accident, subsequently excited by movements of the thorax and by local pressure. In one case (Mulvany) there was slight recurrent hemoptysis.

The recognition of the injury appears always to have been easy, by attention to the difference in level between the cartilage and the sternum. In only one case (Wolfenstein) was it mistaken for a local inflammation. Reduction of the forward dislocations was in every case easily effected by direct pressure, but the tendency to recurrence was marked.

The best treatment would appear to be the application over the displaced cartilage and around the chest of a broad strip of adhesive plaster, as in fracture of a rib, making special local pressure, if necessary, with a compress. Possibly a truss could be used with advantage.

DISLOCATION OF ONE CARTILAGE UPON ANOTHER. (LUXATIO CHONDRO-CHONDRALIS.)

To our knowledge of this subject nothing has been added since Malgaigne wrote upon it; he collected three cases, one of which came under his own observation. They are, in brief, as follows:

Martin. A man seventy years old, while trying to rise from a strained semi-recumbent posture, felt a very painful snap in his chest. Notwithstanding the swelling of the soft parts, an elevation of the cartilages of the last three true ribs (fifth, sixth, and seventh), on the right side, which made this side much more prominent than the other, could be dis

tinctly seen, and the hand could be readily passed under them. He was treated by the application of compresses and a body bandage for a month. The elevation persisted, but was smaller than at first.

Boyer. Of this case Malgaigne says only "Boyer, who saw a similar case under analogous circumstances, was also struck by the prominence of the upper cartilage, but recognized that it was the lower one that was dislocated backward.'

Malgaigne. A man, while pressing a lever forcibly down with his left hand, his body being inclined to that side, felt under his left breast a snap with a sharp pain which for the moment prevented him from straightening himself. Nine years later the deformity attracted the attention of Dr. Séger, who brought him to Malgaigne. The cartilages of the seventh, eighth, and ninth ribs were depressed below the level of the sixth and tenth, which thus formed the borders of a groove at the bottom of which the intermediate ones lay. The skin formed a marked fold in this groove. The three depressed ribs were approximated to and imbricated upon one another, their intercostal spaces being almost obliterated in front. The dilatation of the chest during inspiration was less on the left than on the right side, the patient's gait was a little uneven, and the trunk inclined forward on the left.

CHAPTER XV.

DISLOCATIONS OF THE CLAVICLE.

THE percentages of the frequency of dislocations of the clavicle in the different tables of statistics that have been published vary greatly from one another (see Chapter I.). Thus, of 400 cases of recent traumatic dislocations collated by Krönlein 6 were of the sternal end of the clavicle and 11 of the acromial end, 1.5 and 2.7 per cent. respectively; of 420 collated by Prahl the corresponding numbers were 10 and 3, or 2.38 and 0.73 per cent. In Table III., Chapter I., a total of 1432. dislocations gives 45, or 3.1 per cent., of the sterno-clavicular joint, and 14, or 0.9 per cent., of the acromio-clavicular, while another of 964 cases treated in hospital gives 68, or 7 per cent., of the sterno-clavicular joint and none of the acromial. Polaillon' says that of 967 cases of dislocation treated in the Paris hospitals during four years, 1861-64, 87, or 9 per cent., were of the clavicle. During the same period 609 fractures of the clavicle were treated. Of the 87, 84 were in men, 3 in women; 85 were adults, and 2 were aged. Of 97 reported cases collected by him from medical books and journals, 77 were in men, and 17 in women; in 3 the sex was not stated. He gives the following table of 66 cases classified according to sex and age :

TABLE VIII.-DISLOCATIONS OF THE CLAVICLE; Sex and Age.

And the following of 97 classified according to the variety:

TABLE IX.-DISLOCATIONS OF THE CLAVICLE; VARIETIES.

1 Polaillon: Dict. Encyclopédique des Sciences Méd. Article, Clavicule, p. 717.

(1875.)

Of 50 cases observed by Hamilton, 9 were of the sternal and 41 of the acromial end.

The dislocation may be of either end or of both, and occasionally both clavicles have been simultaneously dislocated.

A. DISLOCATIONS OF THE STERNAL END OF THE CLAVICLE.

Anatomy. The sternal end of the clavicle is so much larger than the clavicular notch of the sternum with which it articulates that it projects

A

FIG. 32.
B

above it and in front and behind. The articular surfaces are separated from each other by an interposed fibro-cartilaginous disk, or meniscus, of varying thickness, which fills the gaps created by the unsymmetrical irregularities of the two surfaces and by their inclination to each other, and extends below the lower edge of the clavicle, separating it also from the cartilage of the first rib. This meniscus is most strongly attached above to the upper edge of the end of the clavicle, and below to the cartilage of the first rib. On each side of it is a synovial cavity. The ligaments of the joint are the interclavicular, costo-clavicular, and the anterior and posterior sternoclavicular. The inter-clavicular ligament extends across from the upper edge of the end of one clavicle to that of the other above the interclavicular notch of the sternum, sending bundles of fibres into the meniscus and to the top of the sternum. The costo-clavicular ligament extends from the sternal end of the first rib upward and outward to the under surface of the clavicle as far as to the subclavian vein, partly surrounding the inner end of the subclavius muscle but lying mainly behind it. It sometimes contains within itself a bursa of considerable size. The anterior and posterior sterno-clavicular ligaments cover in the joint in front and behind respectively, mainly constituting its capsule. They They are short and quite tense.

Frontal section through the sterno-clavicular joint. A, rhomboid or costo-clavicular ligament; B, meniscus; C, interclavicular ligament. (HENLE.)

Motion is possible about all the axes, but only to a comparatively limited extent, the extreme opposite limits being distant about 60° from each other; that is, the acromial end of the bone can be made to describe a circle which is the base of a cone having an angle of 60° at its apex in the joint. Movement of the shoulder downward or downward and backward is arrested by contact of the clavicle with the first rib, and if then continued this point of contact becomes the centre of motion, or the fulcrum, and the sternal end of the clavicle is forced upward or forward out of its place, and a dislocation is produced.

Varieties. The dislocation may be complete or incomplete, upward, forward, or backward; and when complete it is usually also inward, toward the median line, and when complete forward or backward, it is usually also downward. Possibly a separate class of dislocations, upward