Lectures ON INJURIES OF NERVES

1887 The Lancet  
Causes of failure of primary suture of nerve.-I have already expressed my opinion that if the nerve ends have been carefully coapted and kept in position, restoration of function will ensue in the great majority of cases," but I I have no doubt that in some instances no such restoration occurs. The causes of failure are more than one, but those on which I would lay most stress are "sloughing of the nerve ends" and profuse suppuration in the wound. The deleterious effects of sloughing are so
more » ... ous that 1 need not enlarge upon them. It is evident that if portions of the nerves are destroyed union is not to be expected. This sloughing was the probable cause of failure in a case of ulnar suture at St. Bartholomew's Hospital, and also in the case of suture of the peritoneal nerve recorded by lefremowsky. In cases where suppuration is profuse, portions of nerve may be destroyed by ulceration, and even if they escape this fate they are liable to be strangled and compressed by dense scar tissue, as in a case recorded by Busch-Madelung. But net only may the nerve ends be destroyed by the suppuration, the sutures which hold them in apposition may likewise be liquefied, and thus the ends may become separated. I am inclined to think that this accident most probably occurred in the two cases of failure of suture of the ulnar observed by myself, but it is quite possible that pressure by scar tissue may have caused the continuance of the paralysis. The treatment of cases of failure of primary suture is sufficiently clear. In any case where sufficient length of time has been allowed to elapse without restoration of function, the nerve should be exposed at the seat of injury. If its continuity is not interrupted, it should be freed from scar tissue, then thoroughly stretched to free the individual fibrils yet more. If the ends have become separated from any cause, the operation of " secondary suture should be performed as described in the following pages. Treatment of complicated wounds of nerves.-In connexion with this subject I shall allude but briefly to two complications: lst, cases in which the nerve ends are much lacerated and contused; 2nd, cases in which the ends cannot be brought into contact. With regard to the first, the proper treatment, in my opinion, would be the resection of such an amount of nerve as seemed too much damaged to recover, followed by stretching of the proximal and peripheral ends and fixation by suture. That the most satisfactory results may follow such treatment, a case I have already mentioned of a wound of the median nerve supplies ample proof. Here there was a great deal of laceration of the soft parts, and I found it necessary to remove about one inch of nerve which had been almost completely separated from both the upper and lower ends. I did not meet with any material difficulty in bringing the cut surfaces into apposition, and, after fixing the hand in a flexed position on a splint, the case resulted in union by first intention. The second complication I have mentioned is much more serious, for where the ends of the divided nerve cannot be brought into apposition on account of too extensive loss of nerve substance, the prognosis cannot be very favourable. Létiévant has recommended that one of two operations should be performed. First, that the peripheral ends should be grafted on to a freshened surface of some neighbouring trunk; or, secondly, that the proximal end should be split longitudinally to a sufficient extent, a cross section be then made of one-half of the nerve at the highest point to which the splitting is carried, and then that the split portion should be turned down and placed as a sort of graft between the parted ends. 1 am not aware that either of these operations has ever been put into actual practice, but should view each with but little favour. The second suggestion especially seems to be of more than doubtful value, tor the split portion would really be completely separated from each end, and in my opinion would probably slough. In a case where an inch or two of nerve had been destroyed and I was unable to bring the ends into apposition, I should pass sutures through them, and bring them as close as possible by the aid of stretching and of position. In this way further retraction would be prevented, and the two cut surfaces would, at any rate, be fixed in the same plane. I have already detailed cases where union has occurred after excision of several inches of nerve independently of suture, and although I should not give a favourable prognosis, I believe that such treatment would afford the best prospect of recovery. Some experiments by Vaulair are of interest in connexion with this subject. This author details how he resected three centimetres of the sciatic nerve of a young dog, brought the ends as near to one another as possible with sutures, and enclosed them in one of Neuber's decalcified bone drainage tubes. The wound healed readily, and four months later an examination of the seat of injury showed a reunion of the divided nerve. It is evident that the only value this treatment possesses is derived from the fact that the cut ends of the nerve are prevented from becoming adherent to the surrounding tissues, or compressed by the cicatrix. Secondary suture of nerves.-The operation of secondary suture is performed at some time after the infliction of the original injury, generally in cases in which no attempt has been made to secure primary union of the divided nerve. It may be performed either before the wound has healed, or else after it has cicatrised. The indications for such an operation are afforded by the presence of symptoms pointing to the conclusion that a nerve has been divided, and has not united. These symptoms I have already alluded to and described in detail, and will only point out that, as I have already insisted, it is not sufficient to examine the sensation alone of parts supplied by the nerve in question-the conditions and electrical reactions of the muscles are of as great if not of greater importance. With respect to the advisability of performing this operation, I would say in its favour all that I have already said in connexion with "primary suture." In all cases in which a surgeon believes that a divided nerve has not united it is his duty to attempt the suture of the separated ends. In performing the operation it is of prime importance that the parts should be as bloodless as possible, and to obtain this end the use of Esmarch's bandage is most advisable. The limb having been ex-
doi:10.1016/s0140-6736(02)10055-9 fatcat:66p7zmxx6rg7zn4sphdhjuj4ca