Changes in its place of origin have already been noticed. The artery itself is sometimes small, or defective in one or two, or but rarely three of its usual branches.
In these cases, its deficiencies are supplied by a supplemental vessel which has been elsewhere named the u accessory pudic.''' The defect most frequently met with is that in which the pudic ends as the artery of the bulb, whilst the artery of the corpus cavernosum and the dorsal branch of the penis are derived from the accessory pudic. But the three arteries of the penis may be supplied by the accessory pudic : the pudic itself ending as the superficial perineal. In one case, a single accessory pudic supplied both "cavernous" arteries, whilst the pudic of the right side gave both dorsal arteries. And, on the other hand, cases have occurred in which only a single branch was furnished by the accessory artery, either to take the place of an ordinary branch altogether wanting, or to aid one of the branches which happened to be diminutive in size.
The accessory pudic, the occasional artery above alluded to, generally arises from the pudic itself, before the passage of that vessel from the sacro-sciatic foramen, and proceeds forwards near the lower part of the bladder. "In passing by the prostate and urethra — and it is here that the exact situation of this artery is of serious concern to the practical surgeon — the accessory pudic lies on the upper part of the gland, or it may be, for a short space, likewise on the posterior margin ; and then proceeding forward above the membranous part of the urethra, it reaches the perinaeum and divides into the terminal branches." In one case only it was seen to approach the side of the prostate.
The accessory pudic sometimes arises with the other branches from the internal iliac; and a vessel having a similar distribution may spring from the external iliac, through an irregular obturator, or through the epigastric ; in the two last-named cases, it descends directly behind the body of the pubes.