The previous history of all the cases we have collected is totally unknown ; it is re corded of them all, that the arm was re markable for its deficient development, that the fore-arm was in a state of demi-pro nation and demi-flexion, that the movement of extension was incomplete, and of su pination impossible. Cruveilhier, in the ac count he has given of both his cases, states that the superior extremity of the radius was at the level of the summit of the olecranon process (fig. 46), and that the rior or carpal extremity of the two bones of the arm were on the same cise line below, and that no deformity here existed. The head of the radius and bercle were deformed, or ther imperfectly developed, while there was an tion of the neck of the dius upwards for more than an inch. Cruveilhier not concur with those who consider these cases as amples of congenital tions, but looks upon them as old luxations, which had been left unreduced.
For our part we cannot see in these pathological ob servations any thing to con vince us that any one of the cases alluded to was an old luxation originally produced by accident or disease. Sup pose, for argument sake, it be admitted that, from long disease, the form of the capitol= was altogether lost, when the radius was no longer in contact with it, and that the acquired breadth of the sigmoid cavity of the ulna was the result of a natural effort to compensate for the loss of strength the joint suffered from the dislocation of the radius. Still, supposing it possible that the surfiice of the capttulum of the humerus could be so completely removed, under such circumstances, as we find it was in the cases of whichliss. 44 and 45 are delineations, we may ask, is it likely, from accident or disease, that both elbow-joints should be similarly affected, as they were in l)upuytren's cases. Another circumstance in our mind cannot he accounted f.r, unless by supposing these cases congenital, namely, the alteration and great elongation of the neck of the radius. " L'ex treinite superieure de chaque radius avait abandonne sa situation naturelle, se trouvait place derriZ•re l'extremite inferieure de l'hu metals, et depassait cette extremity d'un police au monis. Cette disposition etait ab sulument la rni•me de chaque cide du corps." We know of' no process which could take place in the head and neck of the radius after it had been dislocated, which could satis factorily account for the elongation of the radius, which has been remarked in these cases. While looking on them as congenital, we need not be surprised at it ; for we have known the neck of the femur elongated and atrophied, in the case of congenital luxation of the femur, and have very frequently seen the lower extremity of the ulna exceed in length by half an inch the corresponding extremity of the radius ; and these were cases in which no doubt could be entertained that they were congenital.
Disease.—Acute and chronic inflammation produces effects on the membranes, cartilages, and bones entering into the composition of the elbow-joint, which will be found nearly analo gous to those which the same morbid action pro duces on similar structures in other articulations. A few local peculiarities, if we may so call them, wl:en the elbow is the seat of the acute or chronic disease, should alone occupy our atten tion here.
Synovitis of the elbow-joint, uncombined with any affection of the other structures, is rare ; it may, however, present itself either in the acute or subacute form. Increased effusion of fluid into the joint, accompanied with the usual local and sympathetic phenomena of in flammation, is the result. Two well-marked oblong swellings at each side of the oleeranon process in these cases first present themselves, which after a time, if the disease proceeds, juin and form one swelling, which extends up the back of the arm, occupying the cellular in terval existing between the back part of the humerus and the front of the triceps muscle, opposite to the outer coudyle of the humerus and head of the radius ; the supinators arising here are, in severe eases, occasionally elevated and thrown out from the bones by a soft tumour, which, upon examination, conveys to the fingers a distinct feeling of a fluid contained beneath. The nature of the accumulated fluid will, when the joint is cut into, be found to vary. When the effusion has followed an acute attack of in flammation of the membrane, it will be gene rally found to be purulent, though sometimes we have observed the quality of the synovia but little altered, except that it was more or less turbid. Mien the contents of the synovial sac have been washed away, the membrane will be seen to be highly vascular, and the ves sels of the subsynovial tissue congested with blood, and its cells infiltrated with se rum; while, if fine injection, coloured with vermillion, is thrown into the vascular system of these parts, the unusual redness the mem branes assume can only be compared in height of colouring to the membrane of the eye in acute conjunctivitis. With this intense red ness of the surrounding membranes is strongly contrasted the appearance of the cartilages of the joint ; these, but little altered from their natural colour, are seldom in this articulation found covered with vascular membranes, and even when the surrounding structures are mi nutely injected, the fluid cannot be made to penetrate the synovial investment of the carti lages.