The objective was to define planar anatomy, fascial relationships and struc
ture of the tributary vessels (TVs) of the saphenous veins (SVs). The gross
anatomy of the TVs was evaluated by dissection in cadaver limbs and by son
ography and computerized tomography in healthy volunteers. Correlated light
microscopy and scanning electron microscopy were used to evaluate and comp
are the wall structure in 45 specimens of SVs and 122 specimens of TVs. The
TVs showed a subdermal path and were surrounded by an amorphous fatty tiss
ue. Only the "Giacomini's vein" and the cranial segment of the "anterior ac
cessory saphenous vein" ran deeply in the hypodermis, ensheathed by the mus
cular fascia and the membranous layer of the hypodermis. The wall of the TV
s was weaker than that of the SVs due to the absence of intimal hyperplasia
, to lesser muscularization and to scarce connective tissue proliferation.
The absence of any fascial ensheathing and the parietal weakness are sugges
tive of a lower resistance of the TVs wall to increased endovascular pressu
re. This would explain why varicose changes occurring in the TVs are usuall
y greater than those occurring in the affected SVs.