During childhood and adolescence, our bones grow through a process called ossification. During ossification, calcium and phosphate salts are laid down to replace cartilage or membrane.
Near the ends of each bone are areas of developing tissue that regulate and help determine the length and shape of the bone. These areas of developing tissue near the ends of the bones are known as growth plates or more technically, physis (Figure 1).
The widened part of the shaft of the bone is known as the metaphysis, while the end of the bone is known at the epiphysis.
Because growth occurs at the end of the bone, growth plates are the last portion of the body to ossify or harden. This leaves them susceptible to fractures. Injuries to the growth plates may result in limbs that are crooked or of unequal length. Therefore, immediate attention is required.
When growth is complete, growth plates close and are replaced by solid bone. However, until growth is complete, children are at significant risk for growth plate injuries. Typically, girls and boys near the end of their growth period are especially vulnerable.
Statistically, boys are twice as often as girls to suffer growth-plate injuries. This can be attributed to the female body maturing at an earlier age than boys. In addition, one-third of all growth-plate injuries occur in competitive sports such as football or basketball.
Moreover, about 20 percent of growth-plate fractures occur as a result of recreational activities such as biking, skiing, skateboarding or sledding, according to the American Academy of Orthopaedic Surgeons (AAOS). Growth-plate fractures account for 15-30 percent of all childhood fractures. They most occur most often in the long bones of the fingers, followed by the outer bone of the forearm at the wrist; tibia and fibula growth plate fractures are also common.
Growth-plate fractures are characterized by visible deformities, persistent pain, and an inability to move or put pressure on the limb. If a child or teen experiences any of these signs, they should seek medical attention.
Growth-plate injuries heal without any lasting effects in 85 percent of instances. However, there are certain factors that affect the outcome and management such as severity of injury, age, growth plate affected, and the type of fracture. If injury causes the blood supply to the epiphysis to be cut off, growth can be stunted. In addition, an open injury carries the risk of infection which could destroy growth plates. A child can also affect outcome and management. If a child is younger, growth arrest can be more serious. In addition, some growth plates are more involved in extensive bone growth.
The type of growth-plate fracture are usually categorized in six types (Figure 2).
A Type I fracture describes a break in the bone through the growth plate, but no shift of bone occurs. This fracture usually heals well and requires immobilization.
A Type II fracture is a break through part of the bone at the growth plate and a crack through the bone shaft. This type of fracture is the most common. It is usually treated with cast immobilization, although surgery may sometimes be required.
A Type III fracture is a break through the bone at the growth plate, separating the bone end from the bone shaft and completely disrupting the growth plate. This type of fracture requires surgical treatment in the form of internal fixation to ensure alignment.
A Type IV fracture crosses through a portion of the growth plate and breaks off a piece of the bone end. This kind of fracture is treated with surgery and internal fixation.
A Type V fixation is a break through the bone shaft, the growth plate, and the end of the bone. Fractures like this result in arrested growth and are usually treated with surgery and internal fixation.
A Type VI fracture is similar to a Type V, but the broken pieces of the bone are missing. This fracture occurs only in the case of an open or comminuted fracture. They require surgical repair and possible reconstructive/corrective surgery.