What Causes Numbness In Thigh And Pain At The Back?

I am a softball umpire. I work several games 4 nights a week. This summer I have found that my right hip starts to hurt, then my right thigh starts going numb. When I run the pain eases. When I squat, the pain eases. Nothing makes it go away except sitting, which I cannot do and call softball, despite what people might think. HA HA. I have a catch in my back when I step with my right leg and I think this is all part of the same issue. Suggestions?