Paget’s disease causes bones to grow too large and weak. You can have Paget’s disease in any bones in your body, but most people have it in their spine, pelvis, skull, or leg bones. The disease may affect only one bone or several bones, but it does not affect the entire skeleton.f you have Paget’s disease in your leg bones, you may also have bowed legs. Your spine might curve if the disease is in the bones of the spine. People with Paget’s disease in the bones of the skull sometimes have: 1  Headaches. 2  Hearing loss. 3  Large head size.