Superficial venous thrombosis

[Raeanne Dimick]

Superficial venous thrombosis is inflammation and clotting in a superficial vein, usually in the arms or legs.

The skin over the vein becomes red, swollen, and painful.
Doctors examine the area, but tests are not usually needed.
People may need to take analgesics to relieve pain until the disorder resolves.

(See also Overview of the Venous System.)
Superficial venous thrombosis most often affects the superficial veins (located just under the skin) in the legs but may also affect superficial veins in the groin or in the arms. Superficial venous thrombosis in the arms usually results from having an IV. Superficial venous thrombosis in the legs usually results from varicose veins. However, most people with varicose veins do not develop blood clots (thrombosis).
Even a slight injury can cause a varicose vein to become inflamed (phlebitis). Unlike deep vein thrombosis, which causes very little inflammation, superficial venous thrombosis involves a sudden (acute) inflammatory reaction that causes the blood cot (thrombus) to adhere firmly to the vein wall and lessens the likelihood that it will break loose. Unlike deep veins, superficial veins have no surrounding muscles to squeeze and dislodge a blood clot. For these reasons, superficial venous thrombosis rarely causes a blood clot to break loose (embolism).
Migratory phlebitis or migratory thrombophlebitis is superficial venous thrombosis that repeatedly occurs in normal veins. It may indicate a serious underlying disorder, such as cancer of an internal organ. When migratory phlebitis and cancer of an internal organ occur together, the disorder is called Trousseau syndrome.