114 HENRY O. FEISS 
may be hoped that permanent changes in nerve pattern might 
result, and if two or more nerves are joined, that the mechanical 
attributes of the scar might cause fibers from fascicles of one 
nerve to pass into those of another. Besides, as shown by 
Perroncito,*®® Bethe*! and others, one might even hope for branch- 
ing of some of the regenerating fibers, so that if certain tracts, 
previously emptied by the paralysis, are entered by the new 
branches, there might result not only a change in nerve pattern 
but perhaps also a relative increase in the number of fibers. The 
purpose of the ligature is thus seen—it not only brings the nerves 
into physical apposition, but it also crushes them so as to cause 
the scar to form. Being absorbable (cat-gut) it disappears of 
itself. Compared with the older method of nerve crossing by 
suture, the theoretical advantages are: (1), that no division of 
nerves may be necessary; (2), that as many nerves as are in phys- 
ical proximity may be included in the fusion; and (3), that change 
of nerve pattern may be hoped for in the individual nerve, even 
if no other unites with it. 
Of special interest is the fact that in the cauda, at the region of 
the interspace between the dural exits of the 5th and 6th lumbar 
roots (dog) one may intradurally gather all the roots which supply 
the hind limb and tail into a compact bundle, and fuse them in 
the manner suggested above. In fact, by retracting the sensory 
roots, the motor roots alone may be thus joined together. 
Below are given summaries of experiments in which fusions 
were attempted either in the cauda or in the sciatic nerves, some 
months after primary lesions were produced. These lesions have 
already been described (Part 2). The essential facts in the 
secondary fusions are given in table 3. 
Experimental data*? 
Experiment 64. Lesion, January 18, 1910. On April 27, 1910, resid- 
ual paralysis (fig. 6) chiefly of left external popliteal. On this date, 
following operation, left sciatic exposed, and after faradic stimulation* 
30 Perroncito: Ziegler’s Beitrige, 1907, vol. 42, p. 354. 
1. Bethe: Pfliiger’s Archiv, 1907, vol. 116, p. 385. 
82 All exposures of roots and nerves were made under full ether anaesthesia. 
%¢ Tn all the experiments a du Bois coil with 10,000 windings of the secondary 
and a two-pint Daniell cell in the primary current, were used. 
