Growth Plate Fractures
The bones of children and adults share many of the same risks for injury. However, a child’s bones are also subject to a unique injury called growth plate fractures.
Growth plates are areas of developing cartilage tissue near the ends of long bones. The growth plate regulates and helps determine the length and shape of the mature bone.
The long bones of the body do not grow from the center outward. Instead, growth occurs at each end of the bone around the growth plate. When a child becomes full-grown, the growth plates harden into solid bone.
Growth plates are located between the widened part of the shaft of the bone (the metaphysis) and the end of the bone (the epiphysis). This diagram of a femur (thighbone) shows the location of the growth plates at both ends of the bone.
Because growth plates are the last portion of bones to harden (ossify), they are vulnerable to fracture. In fact, because muscles and bones develop at different speeds, a child’s bones may be weaker than the ligament tissues that connect the bones to other bones.
Children’s bones heal faster than adult’s bones. This has two important consequences:
A child with an injury should see a doctor as quickly as possible, so the bone gets the proper treatment before it begins to heal. Ideally, this means seeing an orthopaedic specialist within 5 to 7 days of the injury, especially if manipulation to align the bone is required.
The fracture will not need to stay in a cast for as long as an adult fracture would require for healing.
Appropriate evaluation by an orthopaedic surgeon experienced in orthopaedic trauma will determine the nature of the growth plate injury, will provide counseling about treatment options, and will allow for longer term follow up to assess the outcome of the injuries.
Approximately 15% to 30% of all childhood fractures are growth plate fractures. These often require immediate attention because the long-term consequences may include limbs that are crooked or of unequal length.
Although growth plate injuries are common, serious problems are rare. Growth deformity occurs in 1% to 10% of all growth plate injuries.
Most growth plate fractures — more than 30% — occur in the long bones of the fingers. They are also common in the outer bone of the forearm (radius), and lower bones of the leg (the tibia and fibula).
Growth plate fractures can result from a single traumatic event, such as a fall or automobile accident, or from chronic stress and overuse.
Any child who experiences an injury that results in visible deformity, persistent or severe pain, or an inability to move or put pressure on a limb should be examined by a doctor.
The area around the end of the broken bone, near the joint, will be swollen, warm, very tender, and may appear crooked when compared to the uninjured side.
To make the diagnosis, the doctor will examine the child and probably use x-rays to determine whether a growth plate fracture occurred. Occasionally, the doctor may request other diagnostic tests, such as magnetic resonance imaging (MRI), computed tomography (CT), or ultrasound.
Treatment depends on the fracture type, as described under “Classification” above.
In addition, there are other factors that may affect the bone growth and fracture healing. These include such things as the age and health of the patient, associated injuries, and the amount of displacement of the broken ends of the bone (occurring through the growth plates).
Type I Fractures
These fractures may result in disrupted bone growth.
Many can be treated with cast immobilization but surgical treatment may be necessary. If surgery is needed, these fractures are often treated with internal fixation (pins) to hold the bone together and ensure proper alignment.
Type II Fractures
These fractures generally heal well, although surgery may sometimes be required. This is the most common type of growth plate fracture.
Most are treated with cast immobilization.
Type III Fractures
This Type III fracture of the thighbone (femur) goes through the growth plate and down into the knee joint. The fracture is fixed in place with screws. This restores normal joint alignment.
These fractures are more common in older children. Because the center of the growth plate has begun to harden, the fracture does not continue across the bone, but angles down and breaks the bone end.
A Type III fracture is treated with surgery and internal fixation to ensure proper alignment of both the growth plate and the joint surface.
Type IV Fractures
These fractures commonly stop bone growth.
They are treated with surgery and internal fixation.
Type V Fractures
These fractures can often be treated with cast immobilization, or may require surgery.
There is almost always a growth disturbance with these fractures.