Paget's disease of bone
Excessive breakdown and formation of bone tissue causing bone to weaken, resulting in bone pain, arthritis, deformities, and fractures. May be caused by a slow virus infection (i.e., paramyxoviruses such as measles and respiratory syncytial virus), present for many years before symptoms appear. There is also a hereditary factor since the disease may appear in more than one family member.
Because early diagnosis and treatment is important, after age 40, siblings and children of someone with Paget's disease may wish to have an alkaline phosphatase blood test every 2 or 3 years. If the alkaline phosphatase level is above normal, other tests such as a bone-specific alkaline phosphatase test, bone scan, or x-ray can be performed.
- Lytic - "blade of grass", osteoporosis circumscripta, cotton wool skull
- Sclerotic - corsened trabecula and cortical thickening, picture frame vertebral body
- Bowing with pathologic fracture
- Sarcomatous degeneration - osteosarcoma
- Neurologic compromise