One out of every 100,000 people is estimated to have<unk> . However, this estimate may be low due to under reporting of cases from asymptomatic or mild conditions. There are many contradicting studies that report different prevalence rates between genders as one study indicates that it affects both sexes equally while other studies purporting that it affects men or women more frequently. The average age of diagnosis is 13 years.<unk>  is not normally diagnosed until early childhood due to lack of visible symptoms present at birth despite lesions being present using radiography. Although most research suggests that<unk>  is spontaneous and nonhereditary, there are some cases where it appears among family members.
Ollier disease
Degos disease
Fox–Fordyce disease
Bayoud disease
Pott disease
Salla disease
Kyrle disease
Texier's disease