Hi, arelative of mine, male, 81 yrs old has been having severe hip and leg pain for almost 6 months, they sent himo cortizone shots that helped for a few days but it came back. He has lost muscle and strength and he finally had a bone gammagram (which we ve never heard of befor) with contrast, the results came out with a dark or black spot on the hip bone, but about 40 days ago he had x rays done and it didnt show anything and the pain was there long befor the spo, what could it be? Thank you so much