Blood clotting in a major vein in one's leg is known as deep vein thrombosis, or DVT, and sometimes appears in the arms, pelvis or other areas, according to the American Society of Hematology.

Blood clotting in a major vein in one's leg is known as deep vein thrombosis, or DVT, and sometimes appears in the arms, pelvis or other areas, according to the American Society of Hematology.

A blood clot is a collection of blood cells and coagulation proteins that clump together, forming a gel-like substance in the blood system that can block blood flow. Blood clots are often triggered by ...