What Causes A Burning Sensation On Thigh Along With Swelling On Legs?

I have been having troubles with my right leg. I have seen the doctors at the VA. I have a severe burning sensation through my right thy, swelling in the leg troubles walking sitting or standing for a long period of time. I have injuries to my L3-4, 4-5, 5&S1. Numbness from my right lower back down through my great to and the next two.