The long saphenous vein compartment

Objective: To define the relationship between the long saphenous vein and the connective framework of the subcutaneous tissue (hypodermis) of the lower limb. Methods: The connective skeleton of the hypodermis was studied by anatomical dissection, stereomicroscopy of cross-sectioned specimens and ultrasound imaging in 88 lower extremities. Results: The long saphenous vein runs for most of its length in a narrow compartment delineated deeply by the muscular fascia and superficially by a connective tissue lamina descending from the inguinal ligament in the anteromedial part of the thigh and medial aspect of the calf. These two fascia fuse at the boundaries of the compartment. The long saphenous vein adventitia is anchored to both fasciase by thick connective tissue strands. Conclusion: The anatomical relationship between the long saphenous vein and the connective framework of the hypodermis suggests that: (1) only the vein running within the deep compartment of the hypodermis should be considered as the 'true' long saphenous vein; (2) the other subcutaneous veins running outside the compartment should be considered as collaterals of the long saphenous vein; (3) the connective sheath surrounding the long saphenous vein could oppose dilatation of this vessel should valvular incompetence develop; and (4) thigh muscle contraction could modify the calibre of the long saphenous vein as happens in the deep veins. Finally, the authors propose to term the deep compartment of the medial thigh and the leg hypodermis the 'long saphenous vein compartment' and consequently the hypodermic connective lamina, by which it is superficially delimited, as the 'long saphenous vein fascia'.