Reports of Societies
Boston Medical and Surgical Journal
Kummer located a sewiug-iieedlo imbedded in the right knee by means of a magnet.21 "A needle was driven into the knee by a blow. Eight days later the movements of the joints were painful, and synovitis developed. It was impossible by palpation to locate the foreign body. The knee was placed upon an electro-magnet charged with a curreut of about ten ampères; on carrying a galvanometer over the surface after removal of the magnet, a deviation was evident. By repeated searching with the
... with the galvanometer the position of the foreign body was accurately determined and the direction of its long axis also became apparent. The surface was marked witii nitrate of silver and the following day the operation was performed. Incision was carried down to the capsule of the joint without finding the needle. On placing a galvanometer needle iu the wound, such an action was manifest that the operator felt no hesitation in opening the joint. A considerable quantity of sanguinolent synovia escaped, and the needle was found in the upper angle of the incisión, lying between the synovia and the fibrous capsule, and corresponding closely in position with that marked on the surface by the aid of the galvanometer," Kocher had a patient in whom, after anomalous nervous symptoms, lasting many months, a needle was discovered by means of the galvanometer ; aud Dumont records a case in which a primary operation was unsuccessful in removing tho foreign body ; but a second operation, aided by tho galvanometer, enabled the operator to reach the seat of trouble. In addition several cases are cited by Graeser, Lauenstein, and Kaliu. BIBLIOGRAPHY. Brown, Dillon. Three hundred cnsos of Intubation ot tho larynx for diphtheritic croup.