I sympathize with your hip pain as it is a problem I also experience. Your description implies that your doctor is not investigating the problem very thoroughly. To be sure that you have the right diagnosis here, have you eliminated piriformis syndrome as a possibility? I understand that sometimes the large muscle that lies near the sciatic nerve can become inflamed and cause excruciating pain through the lower back and/or buttock and/or down the leg. In about 15% of cases, according to what I've read, that muscle and the sciatic nerve are actually intertwined and the pain and resulting loss of flexibility become chronic. This may have nothing to do with your case, but it is not impossible that it might: I would certainly find a physician in your area who has experience treating piriformis syndrome and who can help you find out whether it is a factor in your situation. Best of luck to you whatever you decide.