Teenager's hand bones (13 year old). Coloured X- ray showing the bones in the hand of a thirteen year old teenager. Bones appear white. At this age not much cartilage is seen between each bone joint and ossification (bone formation) has occurred widely so that the spaces between the joints have narrowed. All wrist bones have formed and are visible at centre left. This hand is close to the adult bone pattern. At far left are the radius and ulna bones of the forearm.