What is bone age?
Skeletal age is abbreviated as bone age and is determined by the degree of bone calcification in children. Because bone age can more accurately reflect the level of development at each age during the process from birth to full maturity, it is most widely used in each developmental age, especially in the analysis and diagnosis of endocrine diseases, developmental disorders, nutritional disorders, hereditary diseases and metabolic diseases, where bone age plays a more important role.
How is bone age determined?
Bone age is determined mainly by x-ray, which is usually best on the left wrist. This is where a large number of long bones, short bones and round bones are concentrated, reflecting the growth and maturity of the whole body, and the method is easy and the damage to the human body is minimal. Sometimes, as needed, x-rays of the elbow, knee, ankle and skull can be taken to further determine bone age and distinguish diseases. The degree of bone calcification is judged by three main points, the number and size of ossification centers, the morphological changes of ossification centers and epiphyses, and the healing of epiphyses and diaphyses. The age of a person’s bones can be determined by comparing it to the standard of bone age used as a normal value.
The growth potential of the child can also be determined from the width of the cartilage plate of the long bone epiphysis on the X-ray. The narrowing of the cartilage plate of the metaphysis of the terminal phalanges and the near fusion of the diaphysis with the diaphysis mark the end of the period of rapid growth and the beginning of the period of slowed growth. When the cartilage plate of the epiphysis of the radius and ulna disappears and the backbone fuses with the epiphysis, the long bones of the limbs no longer grow, i.e., the growth of height has basically stopped, and at most the crest (i.e., sitting height) can still grow 1~2 cm.
What is the significance of bone age?
Bone age is used to infer development, thus reflecting the state of physical growth and development, and helps to understand the potential of children’s height development. For example, in the selection of athletes and actors in sports or show business, suppose there are two 11-year-old girls with the same height both 147 cm and other conditions are the same. But one girl’s bone age is only 10 years old, which means there is still a long time for epiphysis to heal, and the other girl’s bone age has reached 13 years old, which is close to the average bone age level of girls’ menarche, and her height is estimated not to increase significantly. Therefore, it can be assumed that the former girl has a greater potential for height growth. In addition, bone age has an important role in the diagnosis, differential diagnosis and observation of the efficacy of short stature disorders, and can also guide doctors whether to use medication and how to treat them.