The deep veins of the leg have different terms to describe their location:

• Upper (proximal) leg veins are those above the knee but below the waist.
  • Popliteal veins are located behind the knee.
  • Iliac and femoral veins are in the groin area.
• Lower (distal) leg veins are those below the knee.
  • Distal leg veins are located in the calf and ankle.

A person with a blood clot in a deep upper (proximal) leg vein is at increased risk for a blood clot in the lung (pulmonary embolism) or other complications.