1. What is a growth plate?
A growth plate is an area of growth cartilage at the ends of tubular bones such as the femur (thigh bone), the humerus (upper arm bone), and phalanges (finger and toe bones). A growth plate actively grows a bone longer and is replaced by normal bone secondary to adolescent hormonal changes. Generally speaking, boys’ legs and arms stop growing at 16 years old and girls’ legs and arms stop growing at 14 years old because their growth plates “close” at those ages.
2. What is growth cartilage?
All of our bones start out as structures made of growth cartilage and gradually turn into bone starting when we are embryos and finishing when we are teenagers.
3. What is a growth plate injury? What is a growth plate fracture?
A growth plate fracture is a break in the bone that occurs at its growth plate. Most growth plate fractures heal completely without any long term bad consequences. In fact, growth plate injuries usually heal faster than breaks in parts of the bones that are distant from the growth plates. A small number of growth plate fractures cause growth plate “arrests.”
4. What does Salter-Harris mean?
The Salter-Harris classification system is the most common way orthopedists and other doctors classify growth plate fractures.
5. What is a growth plate arrest?
Fractures and other mechanisms such as frost-bite can cause a growth plate arrest. The cartilage at a growth plate is replaced by normal bone as a result of fracture healing. If normal bone replaces most or all of a growth plate that end of the bone stops growing (has a complete arrest). If normal bone replaces a portion of the growth plate, that end of the bone grows in the wrong direction (has a partial arrest).
6. What determines if a growth plate arrest occurs or does not occur as a result of a growth plate fracture?
There are many factors that can help the doctor determine the probability of a growth plate fracture resulting in an arrest. The biggest determinants are the site of the injury (which bone was broken) and the “energy of the injury” (how much force broke the growth plate). For example, fractures of the end of the ulna and the end of the femur commonly result in permanent growth plate injuries and injuries of the end of the radius or phalange growth plates hardly ever result in a growth plate arrest. Your pediatric orthopedists knows this subject thoroughly and will be able to fill you in with more detail regarding your child’s injury.