hip pelvis and sarium pain

in aug this year I started getting pain in my back and hip, I went to my gp whom arranged an x-ray for me I was given the result has joint strain to sariotic joint and hip cyst also impingement with restriction of movement,however in nov this year I seen a specialist he told me I have abnormality in both hips by bone growth between ball and socket,and a large degree of bone density within my pelvis.the cyst was visible but gap within sacrium was barely visable because of density mass.can anyone explain what this could be please the doc’s don’t know or wont tell me.