From the Guidelines
Varicose veins in the lower limbs typically follow a specific distribution pattern along the great and small saphenous veins and their tributaries, with the most common distribution including the great saphenous vein system, small saphenous vein system, perforator veins, and reticular veins. The most common distribution of lower limb varicose veins includes:
- Great saphenous vein (GSV) system:
- Medial thigh and leg
- Anterior and medial ankle
- Small saphenous vein (SSV) system:
- Posterior calf
- Lateral ankle
- Perforator veins:
- Scattered throughout the leg, connecting superficial and deep veins
- Reticular veins:
- Fine, bluish veins visible beneath the skin, often on the posterior and lateral thigh This distribution pattern occurs due to the anatomy of the venous system and the effects of gravity and pressure on these superficial veins, as noted in a recent study 1. Varicose veins develop when the valves in these veins become weak or damaged, allowing blood to pool and the veins to dilate. The GSV system is most commonly affected due to its length and the increased hydrostatic pressure it experiences. Understanding this distribution is crucial for proper diagnosis and treatment planning, as it helps healthcare providers identify the source of venous insufficiency and target interventions accordingly, whether through conservative measures like compression therapy or more invasive treatments like endovenous ablation or sclerotherapy, with the goal of reducing morbidity, mortality, and improving quality of life 1.
From the Research
Distribution of Lower Limb Varicosities
The distribution of lower limb varicosities, also known as varicose veins, can be understood by examining the anatomy of the venous system in the lower extremities.
- The long saphenous vein is normally located on the deep fascia, enclosed in a fibrous tissue envelope, and is rarely varicose 2.
- Tributaries of the long saphenous vein typically drain indirectly into it via an arch vein, which can sometimes be mistaken for the long saphenous vein itself 2.
- Perforating veins are found throughout the limb, mainly at intermuscular septa, and can be susceptible to damage, particularly those located medially above the ankle 2.
- Primary lower limb varicosities can arise directly from normal deep venous systems, although this is relatively rare (1.0% of patients referred to a clinic) 3.
- The distribution of vein incompetence and venous hemodynamics in patients with primary varicose veins can be heterogeneous, with some patients having branch venous disease, greater saphenous vein incompetence, or deep and perforating vein incompetence 4.
Anatomic Variations
Anatomic variations of the lower extremity venous system can contribute to the development of varicose veins.
- Three-dimensional CT venography can be used to demonstrate these variations, including the number of tributaries at the saphenofemoral junction, the relative location of the great saphenous vein, and the pattern of the saphenopopliteal junction 5.
- The most frequent number of tributaries joining the great saphenous vein is four (44.4%), and the most common pattern of veins at the saphenopopliteal junction is a larger caliber of saphenopopliteal junction than thigh extension from the small saphenous vein (43.8%) 5.