Small saphenous vein
The small saphenous vein is a relatively large superficial vein of the posterior leg.
Structure
The origin of the small saphenous vein is where the dorsal vein from the fifth digit merges with the dorsal venous arch of the foot, which attaches to the great saphenous vein. It is a superficial vein, being subcutaneous.From its origin, it courses around the lateral aspect of the foot and runs along the posterior aspect of the leg, where it passes between the heads of the gastrocnemius muscle. This vein presents a number of different draining points. Usually, it drains into the popliteal vein, at or above the level of the knee joint.
Variation
Sometimes, the SSV joins the common gastrocnemius vein before draining in the popliteal vein.Sometimes, it does not make contact with the popliteal vein, but goes up to drain in the GSV at a variable level.
Instead of draining in the popliteal vein, it can merge with the Giacomini vein and drain in the GSV at the superior 1/3 of the thigh.