16. But the first mode of reduction is difficult, and the means of maintaining it impracticable. It is necessary, therefore to have recourse to the second, which is the more easily executed, as the scapula follows the movements of the arm, and as, by drawing this limb forward, and the elbow of it outward, that bone is removed from the spinous processes of the vertebræ, and directed in such a manner, as to be brought into contact with its inferior fragment. This situation possesses another advantage, as it throws into a state of relaxation the muscles which tend to displace the lower fragment.
Hence it follows, 1st, That here, in like manner as in fractures of the clavicle, it is not on the fractured bone, that the force must act, but on the humerus. 2dly, That the humerus ought to be, during the whole treatment, immoveably fixed, because its motions, being communicated to the scapula, must soon derange the contact necessary to a reunion.
18. On these principles were founded the apparatus of Desault, and his process of reduction, which consisted, 1st, in drawing the arm forward, and separating the elbow a little from the thorax; 2dly, in fixing the fore-arm at an angle sufficiently acute, to direct the hand to the point of the opposite shoulder; and 3dly, to bring afterwards into proper apposition and form, the fragments already approximated to each other by the first movements.
19. To retain this reduction, the arm and fore-arm must be permanently fixed in the above position. This object is attained in the following manner, 1st, A bolster in form of a wedge, being placed between the arm and the side, its apex situated in the arm-pit, affords the double advantage of keeping the elbow at a distance from the thorax, and of rendering the position of the arm less fatiguing by serving as a point of support to it. 2dly, Compresses wet with some discutient liquid, are applied on the part corresponding to the fracture. 3dly, The whole is now to be secured by a roller, seven or eight yards long. The first turns of this roller, must secure the hand of the affected side on the sound shoulder to which it had been applied, during the reduction, and running afterwards from before backwards, pass over the place of the fracture, for the purpose of retaining the compresses on it. The wedge-formed bolster is to be secured on the thorax, by circular turns around it. Then, passing under the sound arm-pit, after having made these circular turns, the roller must be brought behind again, conducted obliquely over the shoulder of the diseased side, along the anterior part of the arm, under the elbow, and behind the thorax, where it is carried obliquely, in order to pass again under the sound arm-pit. From this place it ascends again anteriorly over the affected shoulder, redescends along the posterior part of the arm, repasses under the elbow, returns under the arm-pit, and terminates finally in circular turns round the trunk, and arm together. Hence it may be observed, that, in the first turns of the roller, this bandage greatly resembles the third roller applied in the fracture of the clavicle, to retain the point of the shoulder upward and backward ([Fig. 4]. plate I.)
20. By this, 1st, The movements of the arm being entirely impeded, they cannot have any influence on those of the shoulder; hence, in this respect, the fragments are suffered to remain in contact. 2dly, The serratus-major and teres-major muscles, being kept in a state of habitual relaxation, can no longer draw the inferior fragment forward, which cannot, therefore, be separated from the body of the bone. 3dly, Nor can the body of the bone, being permanently held in this situation, be removed from the fragment; whence, in both respects, a displacement will be effectually prevented. This threefold advantage is not possessed by any of the different kinds of apparatus hitherto proposed, such as the sling and cross-bandage, employed by Petit, which have the fault of suffering the arm to move backward, of allowing the scapula to be easily separated from its insulated angle, of retarding by that means the cure, and even of preventing it entirely, while, by the process just described, it is usually completed by the thirtieth day.
MEMOIR V.
ON THE FRACTURES OF THE UPPER END OR NECK OF THE HUMERUS.[10]
1. The language of the surgeon differs, in this case, from that of the anatomist, and by the expression, “fracture of the neck of the humerus,” is here meant not that of the slight circular depression, which separates the head from the tuberosities of the bone, but rather that of the contracted or diminished portion of the bone, which commences at the tuberosities above, and being continued down the body of the bone, receives at its lower end the insertion of the tendons of the pectoralis major, the latissimus dorsi, and the teres major. Many practitioners consider this neck or contracted portion as extending even to the insertion of the deltoid muscle.
2. Several facts, the truth of which it is difficult to call in question, attest the possibility of a fracture of the neck of the bone, so called in anatomical language. I have myself seen, in the humerus of a young man, aged seventeen years, the head of the bone exactly separated from its body, by a division which had but slightly affected the upper extremity of the tuberosities. But the examples of this nature which occur in the annals of surgery are too few, to enable us to lay down any general principles for the treatment of such fractures.