What Causes Lump On Thigh?

About 18 months ago I was doing a ballet "plie" (deep bend with knees going out to the side) in an exercise class. I felt the ligaments in my left hip just go crazy. I was able to walk .. just sore. I now have a lump directly at the top of the thigh (the part that bends when you sit). All my physicians have said it is a tension lump. I am concerned. It never goes away no matter how much a message it. Matter of fact it hurts more when I message it and it just gets irritated. I also have lumps in my low back that I believe are episacral lipoma. I am wondering might this lump in my hip be a lipoma or some type of hernia. I have suffered many years with disc herniation. My back, thought not the best, is doing ok. I just have chronic pain in the front of my hip and also several lumps on the side of my hip. I now also have some numbness in the hip. I have suffered with sciatica before so I am very familiar with this sensation. This is different.