What Causes Thigh Numbness With Burning Sensations?

My right leg (thigh) has an area where i can't really feel when I touch the skin. It's been that way for since I spent a lot of time in the Army in cold and rainy weather. Last week I went on vacation and did a lot of walking. About the third day, it started burning like it was on fire in that area. Now it starts burning fairly quickly when I walk. What can it be and what should I do?