I Would Like To Know Which Doctor Can Order A

I would like to know which doctor can order a growth plate x-Ray for a 13 year old boy. Pediatrician, Endocrinologist or Orthopedic Surgeon. I am curious as to approximately how tall my son will be.
He is 13 1/2 and is 5' 6". My wife is 5'1" and I am 6'2".