1952 HUMAN ANATOMY. 



abdominal plexuses is more indirect, "testicular nausea" is less pronounced and is 

 often absent. 



Epididy>no-o?r /litis is usually of infectious origin, the gonococcus and the bacillus 

 tuberculosis being the micro-organisms most often found, although the inflammation 

 may occur in the course of any infectious disease, as scarlatina, mumps, or typhoid 

 fever. 



The direct channel offered by the vas deferens explains the localization of the 

 gonorrhoeal infection (page 1954); the division of the spermatic artery at the epidid- 

 ymis, and the fact that the arteries of the epididymis are smaller and more tortuous 

 than those of the vas or of the testicle, and the consequent slowing up of the blood- 

 current (favoring bacterial growth), may account for the preference shown the epidid- 

 ymis by the general infections. Syphilis more often affects the testicle itself because 

 syphilitic orchitis is usually a late manifestation ; the disease at this stage shows its 

 customary predilection for fibrous and connective-tissue structures, and, beginning, as 

 it often does, as a cellular infiltration of the tunica albuginea, it follows the trabeculae 

 into the interior of the gland. When syphilis affects the testicle during the second- 

 ary stage, it behaves like other infections and is, at least at first, localized in the 

 epididymis. 



A certain number of cases of epididymo-orchitis follow strain, there having 

 been no known infectious cause and no direct trauma. They have the usual symp- 

 toms, — apt to be slight at first, — and occur with much greater frequency on the left 

 than on the right side. Two of various theories as to their production are inter- 

 esting from the anatomical stand-point, (a) Violent co7itraction of the creryiaster 

 nuiscle, which, by suddenly jerking the testicle against the pillars of the external 

 ring, causes bruising of the gland-tissue and the epididymis. The cremaster is cer- 

 tainly capable of vigorous contraction. Thus it is not rarely observed that direct 

 trauma of the testicle is followed by marked retraction of the organ, so that it may 

 be drawn into the inguinal canal or even into the abdominal cavity. Even in severe 

 pain, such as that which accompanies renal colic, the testicles are frequently found 

 in close apposition to the external ring, while any one can observe the contraction 

 of the cremaster by noticing the motion of one or both testicles during the passage 

 of a catheter. Certain cases of chorea of the testicle are at times observed when 

 this organ is moved by the cremaster with considerable rapidity and violence. 

 {b^ Rupture of some of the veins of the spermatic plex2is, which are peculiarly under 

 the influence of intra-abdominal pressure, are provided with but few and imperfect 

 valves, are feebly supported by the surrounding tissues, and hence are especially 

 subject to disease. Thus varicosity of these veins is one of the most common sur- 

 gical affections, and the effect of the contraction of the abdominal parietes and the 

 diaphragm upon the dilated veins is so marked that succussion on coughing or 

 straining in any way is sufficiently distinct to simulate that of an omental hernia. 

 Given, then, a sudden and violent increase of pressure in these vessels, it is perfectly 

 possible to conceive that rupture may occur, even although they are healthy ; this is, 

 of course, more probable if they are weakened and dilated. Such a rupture would 

 naturally take place in the cord, in the epididymis, or even in the substance of the 

 testicle. And, if the theory of venous rupture from pressure is correct, we should 

 expect the left testicle to be more frequently involved (as the veins of this side are 

 more frequently varicose), and the pain to be slight at first and gradually increase as 

 more blood was effused and inflammatory symptoms developed. 



It is not improbable that both of these factors are concerned in the production 

 of this form of epididymo-orchitis. 



The various tumors of the testicle have no especial anatomical significance except 

 as to the routes by which they involve the nearest lymph-nodes {xnde i?ifra). 



Castration, unless modified by extensive malignant disease, is usually done by 

 means of an incision which may be placed over or just beneath the external abdomi- 

 nal ring or even lower, and extends through the scrotal tissues, but not into the 

 tunica vaginalis. The gland with its coverings may, if normal, easily be shelled out 

 and the cord isolated, transfixed, Hgated, and divided. If the vascular constituents 

 of the cord are Hgated separately, three arteries — the cremasteric, the spermatic, and 

 the deferential — must be tied. The deferential artery is found close to the vas, and 



