What you describe about your thigh muscle being painful, especially when lying down reminds me of the pain I had in my hip last year. Have you had an x-ray done of your hip? Seen an orthopedic surgeon for examination of your hip? The pain I had went from the iliac crest (back of the pelvis) around the front, down into my groin area, and down the inner and front thigh. I was unable to pick my leg up even to get in the car. I eventually had my hip replaced because I had bone edema in my hip socket from inflammation from the axial spondyloarthritis. Not saying this is happening to you, but it is eerily similar to the pain you are describing. Rebecca (community advocate)