The bones in both children and adults share similar risks for injury. However, because children are still growing, their bones are also subject to a unique injury known as a growth plate fracture. Growth plates are areas of cartilage located near the ends of bones. They are the last portion of a child’s bone to harden (ossify). As such, this makes them especially vulnerable to fracture.

Growth plate fractures are a common fracture among children, accounting for about 15 to 30 per cent of all childhood fractures. The growth plate helps to determine the future length and shape of the mature bone. As such, growth plate fractures require immediate attention. If not treated properly, they could result in a limb that is crooked or a different length from the opposite limb. Thankfully, severe complications are a rarity. With the proper treatment and care, most growth plate fractures heal well without complications.

Growth plates are found in the long bones of the body that are greater in length than width. Some examples of such long bones include the femur (thighbone), the metacarpal bones in the hands and the radius and ulna in the forearm.

Majority of the long bones in the body have at least two growth plates, including one at each end. Growth plates can be found between the widened part of the shaft of the bone (metaphysis) and the end of the bone (epiphysis). The long bones of the body do not grow outwards from the centre. Instead, growth occurs at each end of the bone around the growth plate. These growth plates harden into solid bone when a child is fully grown.

Majority of growth plate fractures occur in the long bones of the fingers. Other areas where growth plate fractures commonly occur are in the outer bone of the forearm (radius) and lower bones of the leg (tibia and fibula).

How are growth plate fractures classified?

Various classification systems have been developed to categorise the different kinds of growth plate fractures. The Salter-Harris system, listed below, is possibly the most commonly used by doctors.

Type I fractures
Type I fractures break through the bone at the growth plate. They separate the bone from the bone shaft and entirely disrupt the growth plate.

Type II fractures
This is the most common kind of growth plate fracture. Type 2 fractures break through part of the bone at the growth plate and crack through the bone shaft too.

Type III fractures
Type III fractures are more common in older children. They cross through a portion of the growth plate and break off a part of the bone end. 

Type IV fractures
Type IV fractures break through the bone shaft, growth plate and end of the bone.

Type V fractures
A rare kind of fracture, type V fractures occur from a crushing injury to the growth plate from a compression force.

Growth plate fractures are typically caused by a single event like a fall or car accident. They may also occur over time from repetitive stress on the bone, which can happen when a child overexerts during a sports activity.

As long as one is a growing child, they are at risk for growth plate injuries. However, there are additional factors that may increase the chances of growth plate injuries occurring:

• Gender. Growth plate fractures occur twice as often in boys as in girls. This is because girls finish growing faster than boys.
• Adolescence. Most growth plate fractures occur during adolescence.
• Participation in competitive sports. Participation in sports such as gymnastics, football and basketball contribute to one-third of all growth plate fractures.
• Participation in recreational activities. Participation in activities such as sledding, skiing, biking or skateboarding is responsible for around one-fifth of all growth plate fractures.

Common symptoms of a growth plate fracture typically include:

• Persistent or severe pain
• Swelling, warmth, and tenderness in the area surrounding the end of the bone, near the joint
• Visible deformity, such as the limb appearing crooked
• Inability to move or apply pressure on the limb
• Open wounds that cause the bone to be visible (in more severe cases)

It is crucial to get a potential growth plate injury examined by a doctor as soon as possible. An ideal time frame is within 5 to 7 days. This is because a child’s bones heal quickly, and it is important that the bone receives proper treatment before it starts to heal.

First, the child’s symptoms and medical history will be discussed. Next, the doctor will perform a careful physical examination of the injured area.

An X-ray will probably be conducted to determine if a growth plate fracture has occurred. X-rays are able to provide clear images of dense structures such as bone. If the bone needs to be examined in greater detail, other diagnostic imaging tests may be ordered. These can include computed tomography (CT) scans and magnetic resonance imaging (MRI) scans. These diagnostic tests are able to produce a clearer image of the soft tissues or a cross-sectional view of the injured area.

Treatment for growth plate fractures is dependent on multiple factors, such as:

• Which bone is injured
• The type of fracture
• How much the broken ends of the bone are out of alignment or displaced
• The age and health of the child
• Any associated injuries

Nonsurgical treatment

Several growth plate fractures are healed successfully when treated with immobilisation. Immobilisation is where a cast is applied to the injured area and certain kinds of activities are limited.

Normally, cast immobilization is used when the broken pieces of bone are not significantly displaced. A cast is able to protect the bones and hold them in place while they heal.

Surgical treatment

Surgery may be required if the pieces of bone are displaced and the fracture is unstable. Open reduction and internal fixation is the most widely used procedure for treating fractures.

Firstly, the pieces of bone are repositioned into their normal alignment. This is called a reduction. Next, the bones are fixed in place using special implants such as wires or screws. Alternatively, metal plates are attached to the outer surface of the bone.

Lastly, a cast is normally applied to protect and immobilise the injured area while healing takes place.

Even though the majority of growth plate fractures heal without any lasting effects, complications can sometimes occur.

Once in a while, a bony bridge can form across the fracture line, stunting the growth of the bone or causing it to curve. If this happens, a procedure may be performed to get rid of the bony bar and insert fat or other materials to keep it from reforming.

In other cases, the growth plate fracture may even stimulate growth in the injured bone such that it ends up longer than its opposite, uninjured limb. To fix this, surgery can be performed to achieve a more even length.

Although children’s bones heal fast, it can still take several weeks for a growth plate fracture to heal. If cast immobilisation is used, how long the cast needs to be worn will depend on the severity of the fracture.

After the bone has healed, the doctor may suggest certain special exercises. These exercises can help to improve the range of motion in the joint and strengthen the muscles that support the injured area.

In order to ensure successful long-term results, growth plate fractures need to be watched carefully. For at least a year, regular follow-up visits to the doctor should continue. This is to make sure that the growth plate grows appropriately.

As for more complex fractures, as well as fractures to the thighbone (femur) and shinbone (tibia), follow-up visits may be required until the child reaches skeletal maturity.