- Lamellated, layered or onion skin
- Codman triangle
- Spiculated, sunburst or hair on end
Although periosteal reactions may be seen in young and adult populations, the relatively loose attachment and active physiology of the periosteum in children leads to an earlier and more robust reaction to underlying pathology, and is a more sensitive indicator of disease. Lack of a periosteal reaction in adults, who have a tightly adhered and relatively inactive periosteum, is not unusual, even with highly aggressive underlying pathologies. (see the example of adult primary osteosarcoma at the bottom of this post)
Primary osteosarcoma in an adult male. Note the absence of a periosteal reaction.