Paget disease

disease of unknown etiology involving destruction and reparation

age > 40y; M:F 2:1
skull
- osteoporosis circumscripta (outer table destroyed only)
- "cotton wool" appearance
- increased hat size!
spine
- monostotic vertebral involvment usually
pelvis
- affected in 2/3 cases
- consists of cortical thickening
- enlargement of pubis/ischium
- coarse trabecular pattern
extremities
- "blade of grass" appearance
elevation of alk phos (up to 20X), normal calcium, normal phosphorus
complications:
- path fractures in 8% cases (usu. femur = "shepard's crook")
- malignant degeneration (usu. osteosarcoma-50%, fibrosarcoma-25%)