Calcification and Ossification in the Skin

Cutaneous calcification can be divided into four main groups: idiopathic, dystrophic, metastatic and iatrogenic. In idiopathic calcification there is no apparent local tissue injury or abnormal calcium and/or phosphate metabolism. Dystrophic calcification refers to deposits of calcium secondary to trauma or local tissue inflammation. Calcium and phosphate metabolism is normal in dystrophic calcification, which is the most common cause of calcinosis cutis. Metastatic calcification is the result of an underlying defect in calcium or phosphorus metabolism. Finally, cutaneous calcinosis may be iatrogenic. Cutaneous ossification can occur in cases of pre-existng calcification but it can also occur as a primary phenomenon.