When a leg turns purple after a fall, it may be due to the rupture of the subcutaneous capillaries, causing bleeding of the subcutaneous blood vessels, which is a color that occurs when blood cells die. Generally the purple color will slowly fade after the fall, this is due to the healthy cells, gradually absorbed the dead cells, through the blood circulation, the old cells away, out of the body. Some people’s legs, when subjected to external forces do not easily purple, some people are very easy purple, this is because some people capillaries are tougher, not easy to break, some people capillaries are more fragile, it is easy to bleed due to rupture, resulting in the fall injury place into purple, also and platelet high and low have a certain relationship, generally can be absorbed by themselves, will not affect the health of the body. The capillaries are more fragile patients, you can take some vitamin C, under normal circumstances there is no big problem.