|MadSci Network: Anatomy|
I will need some time to find a reference for this. When my children were small they had foot growing pains. The doctor prescribed a dietary suppliment similar to what we have available today as glucosamine sulfate with calcium. That experience leads me to believe that either the muscles are growing faster than bone or visa versa. If the muscles grow faster than bone, the tendons connected to them will "pull" on the bone. If bone grows faster than muscle the muscle is being "stretched" too far too soon. Either of these would cause discomfort and maybe pain in specific areas (where the muscles are connected to the bones). I will try to find some medical writings to back up my thoughts on this.
Try the links in the MadSci Library for more information on Anatomy.