hunch back starting at neck to between the shoulder blades... what disease is it?

i am now 21, in the last 6 months i have noticed i am becoming a hunch back, i am overweight and thought thats what it was, just fat, but when i touch it i can feel bone, its not soft like fat its straight to my spine after the skin, my mother commented on it and said a woman she knows looks like it but hers is worse, its starting to stick out alot more and becoming more noticable. the hump starts at the base of the back of my neck and goes to between my shoulder blades... does any one know what it is or have this themselves?