Growth plate

The epiphyseal plate, epiphysial plate, physis, or growth plate is a hyaline cartilage plate in the metaphysis at each end of a long bone. It is the part of a long bone where new bone growth takes place; that is, the whole bone is alive, with maintenance remodeling throughout its existing bone tissue, but the growth plate is the place where the long bone grows longer (adds length). The plate is only found in children and adolescents; in adults, who have stopped growing, the plate is replaced by an epiphyseal line. This replacement is known as epiphyseal closure or growth plate fusion. Complete fusion can occur as early as 12 for girls (with the most common being 14–15 years for girls) and as early as 14 for boys (with the most common being 15–17 years for boys).