Bone growth and skeletal maturity follow a path determined by hormonal changes managed by an internal clock. Growth spurts are common during puberty (those teenage years) when hormones rise, peak, and then slowly fall back down.
Girls peak sooner than boys. This is usually around age 12 but the range is from 10 to 14. Boys seem to peak closer to age 14 (range from 12 to 16). By the time most girls are 14, they are skeletally mature and not likely to grow any more. Skeletal maturity for boys is around age 16.
These ranges are only estimates. X-rays are needed to determine actual skeletal growth and maturity (end of growth). For example, when children and teens break a bone, the surgeon decides whether to do surgery and what kind of surgical procedure is required based on the type, location, and severity of fracture. But bone age (skeletal maturity) is also a deciding factor.
Even so, adolescents (teens) who have completed bone growth (or nearly completed it) fall into a gray zone when it comes to fracture management. There is still a difference in the quality of bone for that adolescent who isn’t quite an adult yet. There is less mineralization and more blood to the bones compared with an adult. The bones of an adolescent are still a bit more elastic than a fully skeletally mature adult.
Teens with bone fractures (and children, of course) heal faster than adults. Bones in children and adolescents seem to absorb stress, load, and force better than adults. This means they are less likely to break a bone into tiny little parts (as occurs more often in older adults).
For children and teens who are still growing, the physis (growth plate) is at greater risk for fracture than the shaft of the bone. In adults, ligaments are more likely to be ruptured and joints dislocated before the bone breaks. In fact, with some severe soft tissue injuries, it would have been better if the bone had broken because healing is often faster and more straight forward for bone than for soft tissues.