Tributaries of cutaneous drainage
The tributaries of the saphenofemoral junction can constitute anatomical traps:
- when they do not drain directly into the long saphenous vein
- when they communicate with the deep pelvic venous network (Click here).
The tributaries which ensure the cutaneous drainage of regions situated above the inguinal skin crease include, from lateral to medial:
- the superficial circumflex iliac vein which drains the trochanteric region,
- the trunk of abdominal (or epigastric) subcutaneous veins derived from anastomosis of abdominal vessels, especially periumbilical vessels,
- the trunk of superficial external pudendal veins draining veins of the pubic and genital regions.
In 75% of cases, the tributaries drain directly into the arch of the long saphenous vein. However, apart from this classical configuration, three other modes of anastomosis may be encountered: (Figure 23)
- direct drainage into the femoral vein (A) above the saphenous arch (1%) or laterally (9%),
- drainage into the saphenofemoral angle (B) posterior to the arch and anterior to the aponeurosis (6%),
- direct drainage into an accessory saphenous vein (9%) (C).
Three modes of unusual anastomosis of tributaries of cutaneous drainage
- Accessory saphenous vein
- Long saphenous vein
- Femoral vein
- (A, B, C: see text)
When the tributary drains directly into the femoral vein, the trap most frequently encountered is that of an abdominal subcutaneous vein which drains laterally into this vein. This difficulty can be overcome by performing a sufficiently large surgical dissection.
More rarely (1 %), the tributary drains into the femoral vein above the arch of the long saphenous vein (Figure 24), in which case it is more difficult to identify. However, recurrence via this vessel can only occur when there is a communication with the intrapelvic system or in the presence of hypertension of the iliofemoral system.
Direct drainage into the femoral vein
- Superficial circumflex iliac vein
- Trunk of superficial external pudendal veins
- Trunk of abdominal subcutaneous veins
The tributary may also drain into the saphenofemoral angle. In Figure 25, the superficial circumflex iliac vein enters the femoral vein underneath the saphenofemoral junction and behind the long saphenous vein, underneath the saphenofemoral junction and behind the long saphenous vein.
It may therefore pass unnoticed, as it is masked by the arch of the long saphenous vein. Recurrences following resection of the saphenofemoral junction may occur when the ligation is not performed flush to the femoral vein, at the site of the last ostial valve.
Finally, tributaries can also drain into an accessory saphenous vein (Figure 26). Accessory saphenous veins constitute a frequent cause of post-stripping recurrence and varicosities (Click here).
This risk is even higher when these veins receive tributaries, especially tributaries lying outside of the surgeon’s field of vision. The variant illustrated here (Figure 26) is a configuration in which the long saphenous vein receives an abdominal subcutaneous vessel obliquely superomedially as well as a superficial external pudendal vein. The deep external pudendal artery, branch of the femoral artery, passes through the saphenofemoral angle. The accessory saphenous vein, independently of the long saphenous vein, receives a superficial circumflex iliac vein, which perforates the fascia lata away from the saphenous opening and therefore probably outside of the surgeon’s field of vision. When there is a communication between this circumflex vein and the deep system, the accessory saphenous vein may be supplied away from the saphenofemoral junction.
De Simone J.G., Brizzio E. Étude du confluent veineux saphéno-fémoral par échotomographie. Phlébologie, 1988, 41: 449-60.
Kosinski C. Observations of the superficial venous system of lower extremity. J. Anat, 1926, 60 : 131.
Von Lantz T., Wachsmuth W. Praktische Anatomie, Springer Ed., Berlin, 1959, I.