Although age is not necessarily a prerequisite, many ballet students do not begin to dance en pointe earlier than approximately 12–14 years of age because bones in the feet are often too soft prior to that age and in such cases, serious and permanent foot injuries could result from starting pointe work too early. The long bones in feet begin to harden within the ages of 8 to 14, dancing en pointe before one's bones have hardened can lead to trauma and growth-plate fractures that create deformed feet.