I was diagnosed at age 5 and had a bone age of around 13 years at that time. Each year it was reviewed and my bone age increased by about 1 month each year until I was about 11 when it had shot up to 15 years, my medication was adjusted and this slowed down the progression of bone age. By the time I was 16 everything caught up so my bone age was also 16. It was explained to me that the bone age will always be ahead of my actual age until I reached my teens then it may only be slightly ahead (less than 1 month)

 

Hope this helps