Spider veins and varicose veins are a common disease
You will find detailed information in our vein dictionary
Side branch veins
The side branch veins run through the lower leg and the thigh; there are many veins connecting them with each other and also to the deep vein system. Side branch varicose veins may develop if their valves are incompetent (leaky). The term “side branch veins” is not really accurate: strictly speaking, trunk veins do not give off branches, but rather the blood comes from the side branch veins emptying into the trunk veins. For the sake of simplicity, however, “side branch veins” continues to be used, as it is such a well-established term.