Great saphenous vein: the long superficial vein of the leg

What it is

The great saphenous vein is the longest vein in the body and runs up the medial side of the leg and thigh.

Location

It begins at the medial end of the dorsal venous arch, ascends in front of the medial malleolus, then behind the medial femoral condyle and joins the femoral vein through the saphenous opening, about 3 to 4 cm below and lateral to the pubic tubercle (the saphenofemoral junction).

Function

It drains the superficial tissues of the medial leg and thigh.

Body system

Cardiovascular · paired (left and right)

FMA ID

FMA21380 (Foundational Model of Anatomy)

Key facts

• It is often used as a graft in coronary bypass surgery. The saphenous nerve runs with it in the leg.
• It has several valves along its length; one study of normal veins found a mean of about 7 in the trunk, with at least 6 in most.

Clinical relevance

It is commonly affected by varicose veins. Its position in front of the medial malleolus is reliable, so it is used for emergency venous cutdown.

There are two saphenous veins in each lower limb, and both are superficial veins: they run in the fatty tissue under the skin rather than with the arteries under the deep fascia. The great saphenous vein runs on the medial (inner) side of the leg and thigh; the small saphenous vein runs up the back of the calf. Both drain into deep veins. (TeachMeAnatomy: Venous Drainage of the Lower Limb.)

Radiopaedia recommends the name great saphenous vein over long saphenous vein, greater saphenous vein and internal saphenous vein, and small saphenous vein over short, lesser or external saphenous vein. Older textbooks and many clinicians still use the alternatives. (Radiopaedia: Small saphenous vein.)

OpenStax describes the great saphenous vein as a prominent surface vessel on the medial surface of the leg and thigh that drains into the femoral vein, and the small saphenous vein as draining the superficial regions of the lower leg and foot. (OpenStax Anatomy and Physiology 2e, 20.5: Circulatory Pathways.)

In the 3D model the great and small saphenous veins are highlighted with the femoral and popliteal veins that they drain into and the dorsal venous arch of the foot where they begin. The model is BodyParts3D, an adult male; it does not show the saphenous nerve or the accessory saphenous veins.

The great saphenous vein begins on the dorsum (top) of the foot at the medial end of the dorsal venous arch, as the continuation of the medial marginal vein. It passes in front of the medial malleolus, runs up the medial side of the leg and then behind the tibia, curves round the medial side of the knee and climbs the medial thigh. (Radiopaedia: Great saphenous vein.)

Meissner adds that it crosses the tibia at the junction of its lower and middle thirds and passes behind the knee on the medial side. (Meissner MH. Lower Extremity Venous Anatomy. Semin Intervent Radiol. 2005.)

Near the groin the vein pierces the deep fascia of the thigh at the saphenous opening (saphenous hiatus), arches over and joins the femoral vein on the medial side of the femoral triangle. (Kenhub: Great saphenous vein.)

The saphenofemoral junction is where the great saphenous vein enters the common femoral vein. Meissner places it about 3 to 4 cm below and lateral to the pubic tubercle; Radiopaedia places the saphenous hiatus about 1 to 3 cm below the inguinal ligament. The two figures are measured from different landmarks. (Meissner MH. Lower Extremity Venous Anatomy. Semin Intervent Radiol. 2005.)

Radiopaedia reports a valve in about 99% of people, 1 to 2 mm below the junction. The vein receives several named tributaries, including the superficial epigastric, superficial circumflex iliac and superficial external pudendal veins and the anterior accessory saphenous vein. (Radiopaedia: Great saphenous vein.)

Meissner reports a valve at the junction in 94 to 100% of people and at least one more valve higher up, in the common femoral or external iliac vein, in 81%. (Meissner MH. Lower Extremity Venous Anatomy. Semin Intervent Radiol. 2005.)

Along most of its length the great saphenous vein lies in its own saphenous compartment, bounded by the saphenous fascia on the outside and the deep (muscular) fascia, the fascia lata in the thigh, on the inside. On an ultrasound cross-section the two fascial layers and the vein look like an eye, the sonographic Egyptian eye sign. (Radiopaedia: Great saphenous vein.)

The main trunk usually has at least six valves. Meissner found an average of 7.3 in normal veins and 6.0 in varicose veins, though the meaning of that difference is unclear. Other sources give different totals, so treat any single number as approximate. (Meissner MH. Lower Extremity Venous Anatomy. Semin Intervent Radiol. 2005.)

Valves in limb veins are flaps of thickened endothelium reinforced by connective tissue. They let blood move only towards the heart. (OpenStax Anatomy and Physiology 2e, 20.1: Structure and Function of Blood Vessels.)

In the calf the great saphenous vein usually has two main tributaries, an anterior branch and the posterior arch vein. The posterior arch vein drains the veins around the medial ankle and receives the posterior tibial perforators. In the thigh, anterior and posterior accessory saphenous veins run parallel to it outside the saphenous compartment. (Meissner MH. Lower Extremity Venous Anatomy. Semin Intervent Radiol. 2005.)

Perforating veins pierce the deep fascia to link the superficial and deep systems. In the calf, the paratibial perforators join the great saphenous vein to the posterior tibial veins. In the thigh, the femoral canal perforators connect it, about 15 cm above the knee, to the deep veins of the lower thigh. Except in the foot, perforators normally carry blood from superficial to deep. (Meissner MH. Lower Extremity Venous Anatomy. Semin Intervent Radiol. 2005.)

Kenhub still uses the older eponyms for some perforators, such as the perforator of Boyd near the knee and of Dodd in the thigh. Meissner notes that current consensus advises dropping eponyms in favour of names that describe the location. (Kenhub: Great saphenous vein.)

The saphenous nerve is the terminal skin branch of the femoral nerve. It runs through the adductor canal, leaves it before the adductor hiatus and then accompanies the great saphenous vein down the leg, supplying the skin of the medial leg and foot. (TeachMeAnatomy: The Femoral Nerve.)

Below the knee, branches of the saphenous nerve lie both in front of and behind the vein. Above the knee the nerve is not closely related to the vein and lies outside the saphenous compartment. (Radiopaedia: Great saphenous vein.)

Because of this close relation in the leg, the nerve can be injured when the vein is stripped or treated below the knee, causing pain, pins and needles or numbness over the medial lower leg. (TeachMeAnatomy: The Femoral Nerve.)

The small saphenous vein begins from the dorsal venous arch and the dorsal vein of the little toe. It passes behind the lateral malleolus, runs up the back of the calf beside the lateral border of the calcaneal (Achilles) tendon and, at the knee, passes between the two heads of gastrocnemius to empty into the popliteal vein. (TeachMeAnatomy: Venous Drainage of the Lower Limb.)

Its ending varies. Meissner found that about 60% join the popliteal vein within 8 cm of the knee joint, about 20% join the great saphenous vein, and about 20% end in the femoral, deep femoral or internal iliac vein. The small saphenous vein usually has 7 to 10 closely spaced valves, and the sural nerve runs right beside it. (Meissner MH. Lower Extremity Venous Anatomy. Semin Intervent Radiol. 2005.)

A common upward extension, the vein of Giacomini, runs between biceps femoris and semimembranosus on the back of the thigh. Radiopaedia gives a prevalence of about 80%, and duplication of the small saphenous vein in about 3.5% of people. (Radiopaedia: Small saphenous vein.)

Radiopaedia lists segmental hypoplasia (an underdeveloped segment) and duplication of the great saphenous vein, which it says is seen only in the thigh in about 1% of people, with both trunks inside the saphenous compartment. It treats veins that run alongside but outside the compartment as accessory saphenous veins, not duplicates. (Radiopaedia: Great saphenous vein.)

Meissner gives higher figures for true duplication, about 8% of thighs and 25% of calves. Part of the difference may come from how duplication is defined. Meissner also notes that the vein sometimes leaves the compartment in the thigh, where it lacks fascial support. (Meissner MH. Lower Extremity Venous Anatomy. Semin Intervent Radiol. 2005.)

Varicose veins form when faulty valves let blood collect in the veins, which then stretch and become visible. They are common in the lower limbs, especially in the superficial veins of the legs, and are more common in women, often in connection with pregnancy. (OpenStax Anatomy and Physiology 2e, 20.1: Structure and Function of Blood Vessels.)

Meissner defines varicose veins as dilated, palpable, twisting veins more than 4 mm across. In a study of 839 legs with large varicose veins, reflux in the great saphenous vein was found in 51%, and only two thirds of those had reflux at the saphenofemoral junction, so varicose changes can start anywhere along the vein. (Meissner MH. Lower Extremity Venous Anatomy. Semin Intervent Radiol. 2005.)

Long-standing cases can cause brown skin pigmentation and ulcers. Treatments include thermal ablation, ligation with stripping or avulsion through a groin or popliteal (back of the knee) incision, and foam sclerotherapy. (TeachMeAnatomy: Venous Drainage of the Lower Limb.)

Superficial thrombophlebitis, a clot with inflammation in a superficial vein, often involves the great saphenous vein. Kenhub lists immobility, trauma and some cancers as predisposing factors. (Kenhub: Great saphenous vein.)

The great saphenous vein is long and close to the surface. It can be harvested as a conduit for coronary artery bypass grafting, where it is sewn in to carry blood around blocked coronary arteries. (TeachMeAnatomy: Venous Drainage of the Lower Limb.)

Kenhub describes the procedure: a length of vein is removed from the leg and sutured to bypass the coronary blockages while the patient is on cardiopulmonary bypass. (Kenhub: Great saphenous vein.)

Vein grafts are also used in the leg itself. Open repair of a popliteal artery aneurysm is usually an aneurysm repair with a bypass, typically using a vein graft, and about 70% remain open at five years. (Radiopaedia: Popliteal artery aneurysm.)

The nearest named structures in the 3D model, measured from the centre of each part:

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