Epidemiology

Camptodactyly affects about 1% of the population, but this may be an underestimate as mild deformity may go unrecognised. It most commonly affects the little finger. It can run in families with an autosomal dominant inheritance. In two thirds of cases, it is bilateral; however, there may be asymmetry between the sides in terms of the extent of flexion.

Demographically, there are typically three groups that it afflicts:

• type I:
  • a congenital form first recognised in the early years of life
  • no gender bias
  • usually only affects little finger
• type II:
  • an acquired form first recognised from 7 to 14 years
  • has a female gender bias
  • does not improve spontaneously
  • may progress to a severe flexion deformity
• type III:
  • severe form
  • affects multiple digits on both hands
  • may be asymmetrical
  • associated with a number of syndromes (see submenu)

Additionally, a minority of patients may have camptodactyly secondary to trauma.