Perforating veins

At a glance

English

Perforating veins

Latin (TA2)

Venae perforantes

System

Vein

Region

Lower limb

Side

Paired, left and right

About the perforating veins

Perforating veins, or perforators, are named for the way they pass through the deep fascia that wraps the muscles of the limb. Each links a superficial vein in the subcutaneous fat, such as a tributary of the great or small saphenous vein, with a deep vein lying among the muscles. They are found all along the lower limb, more numerous below the knee than in the thigh. In the thigh, perforating veins also accompany the perforating arteries through the adductor muscles to reach the deep femoral vein, and that set is the one shown on this page.

Their valves allow blood to move only one way, from superficial to deep. When the calf or thigh muscles contract, the deep veins are squeezed and blood is driven towards the heart; the valves in the perforators stop that pressure from being pushed back out into the thin-walled superficial veins. When the muscles relax, the deep veins fill again, partly from the superficial system through the perforators.

Several groups have their own names. Thigh perforators link the great saphenous vein to the femoral vein in the adductor canal. Below the knee, a group near the knee and mid-calf connects the great saphenous system with the posterior tibial veins, and the medial ankle perforators join the posterior arch vein to the posterior tibial veins just above the medial malleolus.

When perforator valves fail, the high pressure of the deep veins reaches the skin during every step. This contributes to varicose veins and to chronic venous insufficiency, with swelling, skin pigmentation and ulcers that gather around the lower leg and medial ankle. Incompetent perforators can be found with duplex ultrasound and closed by surgery, foam injection or thermal ablation.

Course and drainage

Begins at

Arise from superficial veins of the lower limb, such as tributaries of the great and small saphenous veins.

Drains into

Pierce the deep fascia to end in deep veins; in the thigh the perforating veins of the adductor region join the deep femoral vein.

Drains

Carry blood from the superficial to the deep venous system and, through their valves, protect the superficial veins from deep pressure during muscle contraction.