I. Anatomical differences
Most children's bones contain X-ray transparent growth cartilage, so many injuries will affect the thickness of the growth plate or separate the epiphyseal plate from adjacent bones on plain film. The exoskeleton is thick, and the callus appears faster and more than adults.
Second, biomechanical differences.
Children's bones are more flexible and more resistant to external deformation than those of adults. Small holes in children's bone cortex can limit the expansion of fracture lines, just as cracks in the walls adjacent to windows are not easy to expand after drilling. Adults' compressed bones can't bear tension. On the contrary, children's bones with rich pores are not easy to compress.
Third, the epiphyseal plate
The epiphyseal plate or growth plate is the cartilage layer connecting the epiphysis and the metaphyseal end. It is related to the growth of bones.
Fourth, physiological differences.
1, growth and shaping: growth provides conditions for shaping to a great extent. With the increase of bone length and circumference, the deformity caused by fracture can be corrected by asymmetric growth of epiphysis and periosteum.
2. Overgrowth: Long bone fracture in children is accompanied by increased local blood supply, which increases the nutrition of growth plate and stimulates the longitudinal growth of bone. For the femoral shaft fracture without displacement, the injured femur can be about 1cm longer than the healthy femur within 1-2 years.
3. Progressive deformity: the permanent damage of the growth plate will lead to bone shortening or progressive angulation deformity.
4. Healing speed: Children's fracture healing ability is strong, and fractures should be restored as soon as possible. We shouldn't think about it for too long as we do about adult fractures.
Children's fractures are different from those of adults in many aspects, and the relatively fragile epiphyseal plate is easy to be injured. Understanding the diversity of epiphyseal plate injury and adopting modern treatment methods are the central link of treatment. Active growth and good blood supply ensure the good fracture healing of most children. However, the unique characteristics of children's bones may also lead to some progressive deformities. Therefore, children are not the epitome of adults, and children's fractures cannot be treated according to the viewpoint or method of adult fractures, but corresponding methods should be taken according to the characteristics of children's bones to ensure reasonable treatment.