730 HUBER. [Vol. XI. 



an ordinary suture cannot be made, and when the injury occurs 

 at a different level in the two nerves, which modification 

 consists in grafting the short segments of the two divided 

 nerves to the long one, after they have been cross-sutured, 

 would not seem to be of any value, as, I think, this experiment 

 clearly shows. 



General Conclusions. 



A review of all the experimental work reported by other 

 writers and myself, dealing with the operative treatment of a 

 divided peripheral nerve after loss of substance to the extent 

 that an ordinary nerve suture cannot be made, and of such 

 clinical cases as I have been able to collect, will, I think, 

 warrant the following conclusions : — 



I. That it is possible to restore the functional activity to 

 the peripheral part of a divided nerve with loss of nerve sub- 

 stance, if the resected ends are united with a segment taken 

 from some other nerve trunk, with catgut threads, or with a 

 bone-drain or tubular suture. 



II. Of all the methods tried (implantation of a nerve segment, 

 tubular suture, suture a distance, nerve flap, grafting the central 

 end of the peripheral stump of a divided nerve to an accom- 

 panying uninjured nerve, and cross-suturing long ends and 

 grafting short stumps where two nerve trunks are cut at a 

 different level) the most favorable results are to be obtained 

 after the implantation of a nerve segment, the two ends of 

 which have been sutured with one or several direct catgut 

 sutures to the resected ends of the injured nerve. The favor- 

 able results obtained by Assaky in his experiments of suture a 

 distance, and Vanlair after bone-drain suture, are not, I think, 

 exceptions to this statement ; as in their experiments much 

 shorter segments were removed from the nerve operated upon 

 than was the case in my experiments of resecting a nerve and 

 implanting a segment from another nerve trunk, to which fact 

 the somewhat earlier return of function recorded by them can 

 be attributed. 



III. The regeneration of the peripheral end (which always 

 degenerates so that only the old sheaths of Schwann, containing 



