382 MEDICINE, ADVANCES IN. 



METALLURGY. (GENERAL.) 



congenital dislocation, both hips being deformed, 

 and the Chicago surgeon's operation resulted, it 

 is said, in curing but one joint. The hip-joint 

 is formed by a hemispherical depression in the 

 pelvic bone, called the acetabulum, and a round, 

 ball-like protuberance from the upper end of the 

 thigh bone, or femur, set almost at right angles 

 to the shaft. This protuberance fits into the 

 socket of the pelvic bone and forms what is 

 known as a ball-and-socket joint. In congenital 

 dislocation of the hip, either because of some 

 imperfection in the ball or in the socket, or 

 through a prenatal accident, the ball and the 

 socket are separated, and because of the arrange- 

 ment of the muscles surrounding the socket, the 

 head of the femur is displaced upward, usually 

 either backward or forward. The object of the 

 Lorenz operation is to replace the ball in the 

 socket and hold it there until the joint has re- 

 covered its power sufficiently to retain the cor- 

 rect position without the use of the knife. After 

 the dislocation has existed for some time the 

 surrounding muscles become contracted, and 

 great force is required to stretch or tear them suf- 

 ficiently to permit the ball to drop back into its 

 socket. Hence the essential part of the opera- 

 tion consists in stretching and tearing the mus- 

 cles until they are limp and functionless. This 

 is accomplished by Dr. Lorenz in the following 

 manner: An anesthetic is given; an assistant then 

 firmly holds the pelvis of the child, while the 

 doctor raises the leg forward and upward until 

 the foot is carried to the shoulder; this is done 

 gradually, the muscles meantime being kneaded 

 and massaged, especially at the points where they 

 are fastened to the bone. The child is now 

 turned on its face, and the same extreme stretch- 

 ing produced in the opposite set of muscles by 

 carrying the leg backward and upward. The leg 

 is drawn away from its fellow abducted, as it is 

 called and the inner thigh muscles thus stretched 

 and torn. These movements are continued until 

 the muscles about the thigh are all quite flaccid. 

 The skin is usually considerably bruised during 

 this operation. The femur is now drawn down 

 until the ball is opposite the socket, and then 

 manipulated until it drops into the latter. Dr. 

 Lorenz is thus quoted regarding the sensations 

 produced by the curious click that is heard when 

 this occurs : " The event, always expected with 

 great tension of mind and deep longing, is ac- 

 complished like the triumphal entrance of a 

 princely lord through the doors of his hereditary 

 residence, from which he has been excluded for 

 a long time through stress of circumstances, amid 

 the chiming of bells, the beating of drums, and 

 the firing of cannon which shakes the foundation 

 of his castle. And yet this plaintive music of 

 nature is for the parched ears of the operator a 

 sound-intoxicating song of the spheres; as long 

 at least as he preserves, during his laborious 

 work, a receptive soul for such enjoyment." 



Owing to the flaccid, rag-like condition of the 

 muscles, the newly formed joint is not stable, 

 so that a redislocation is very apt to occur. In 

 order to prevent this, the leg is drawn out side- 

 wise so that it rests at an angle of 90 degrees 

 with the body, and maintained in this position 

 by a plaster cast. The pains due to the opera- 

 tion subside in a few days, and the child is then 

 encouraged to walk about and play. Dr. Lorenz 

 lays great stress on the early use of the limb, 

 holding that the pressure of the head of the 

 femur in the acetabulum, caused by the weight 

 of the body, is an important element in causing 

 the reformation of a useful and efficient joint. 



In his earlier operations- mechanical contri- 



vances were used for stretching the leg and draw- 

 ing down the femur, but these are now rarely 

 required by Dr. Lorenz, although it is probable 

 that the surgeon of average strength will have to 

 resort to them much more frequently. He now 

 leaves the plaster cast in place for six months 

 to two years; his early practise was to remove 

 it after three months, and, if necessary, put on 

 another. He holds that a cure is obtained in 

 about 60 per cent, of his cases, and an improve- 

 ment in nearly all. It is said by other surgeons 

 that the cutting operation is equally successful. 



Dr. Lorenz has applied the same bloodless 

 methods to the treatment of other joint and bone 

 deformities, and even to wryneck. Stiffened 

 knees and clubfoot are corrected by the intra- 

 articular modeling redressement, as he calls hi* 

 powerful massage, and the shortened (sterno- 

 cleidomastoid) muscle in cases of wryneck is torn 

 apart and stretched instead of cut, as by the 

 old method., 



One of his principles is to save the bone, even 

 at the expense of the soft parts. He believe* 

 that efforts should always be made to cause the 

 patient's own anatomical apparatus to correct 

 a deformity, or a tendency thereto, whenever pos- 

 sible, rather than to clothe him in a suit of mail 

 or a cage of steel rods. In chronic joint disease 

 he uses as little apparatus as possible, and dis- 

 cards it early. 



The Lorenz bloodless operation is by no means 

 entirely free from danger. Among the few pa- 

 tients operated on in Chicago there was one case 

 of fracture of the femur, another in which an 

 extensive blood tumor formed, and a third in 

 which severe- tearing of the perineum occurred. 



METALLURGY. General. In a lecture on 

 the Relations between Metallurgy and Engineer- 

 ing, delivered before the Institute of Civil En- 

 gineers, Sir W. C. Roberts-Austen pointed out 

 that when metallurgists gave engineers mild steel 

 they provided a carbon-free solid solution of iron 

 and carbon. All subsequent advance had been 

 due to recognition of this fact and to the profound 

 studies of metallic solid solutions. Sir John 

 Hawkshaw had said that if the strength of iron 

 could be doubled the advantages might be equal 

 to the discovery of a new metal more valuable 

 than iron ever had been. The lecturer believed 

 that this was exactly what metallurgists had done 

 with regard to steel. By suitable thermal treat- 

 ment and by suitable addition of comparatively 

 rare metals they had doubled the strength of 

 steel as it was made in the early days. Having 

 explained the nature of solid solutions, the lec- 

 turer dwelt upon the importance of allotropic 

 modifications of iron, and cited evidence of the 

 possibility of the past molecular history of a 

 mass of steel being traced by microscopic exami- 

 nation of the metal. It was demonstrated that 

 solid metals might reveal, by their structure, the 

 vibrations to which they had been subjected. 

 With regard to the efforts metallurgists were ma- 

 king to study the influence of rare metals on iron 

 and other metals, the reducing power of aluminum 

 on metallic oxids was shown. The need for the 

 careful measurement of high temperatures in con- 

 nection with the treatment of large masses of 

 metal was illustrated by reference to the new 

 Alexander III Bridge in 'Paris. In the construc- 

 tion of this bridge 2,200 tons of cast steel had 

 been employed, and a peculiar molecular structure 

 was imparted to this steel by rapidly cooling it 

 in air from a temperature of 1,000 C. to 600 C. 

 This gave the metal certain mechanical properties 

 which it would not otherwise have ]x>r--pil. 

 The use of copper, aluminum, and other metals in 



