Diagnosing Growth Plate Injuries

The growth plates are sections of soft cartilage near the ends of bones where new bone forms as children and teens grow. As your child matures, these growth plates eventually harden and turn into bone, or “close.” While growth plates are “open,” these fragile areas can fracture. In fact, they may be more vulnerable to injury than the bone, tendons, muscles, and ligaments that surround them.

Growth plate injuries tend to occur in the arms, legs, or fingers, and for the same reasons as sprains and other injuries: from falls, bumps, and other traumas during physical activity. Something as simple as a fall from the monkey bars or an awkward landing on a trampoline could lead to a growth plate injury.

A growth plate injury may cause swelling or a noticeable bump at the site of the injury, and an affected leg or arm may even appear slightly bent. As with a sprain or pulled muscle, a child with a growth plate injury may have pain or tenderness at the site of the injury and difficulty moving the affected area.

Many growth plate injuries are mild and heal well without treatment. But more severe injuries can cause the affected growth plate to close too early or produce bone more quickly. This can lead to complications, such as a curve in the bone, one leg that is longer than the other, and even early arthritis.

If your child feels pain from an injury or can’t use the affected area for 12 to 24 hours, or if you otherwise suspect a serious injury has occurred, consult a doctor as soon as possible. Our orthopedists can diagnose growth plate injuries and take the necessary steps to prevent complications.

Physical Exam

In order to diagnose your child’s injury, doctors first conduct a physical examination. The doctor may check your child’s range of motion near the injury and look for signs that the bone is out of alignment. The doctor looks for tenderness directly over the growth plate, one important sign of a growth plate injury.

Imaging Tests

In addition to a physical examination, our doctors may use the results of one or more of the following imaging tests to diagnose the injury.

X-ray

The symptoms of a growth plate injury may be similar to those of a sprain, a pulled muscle, or a broken bone, and so doctors usually recommend an X-ray to get a better sense of the cause of your child’s symptoms. Because growth plates are made of cartilage, they don’t show up clearly on an X-ray and instead appear as an empty space between the middle section of a bone and the end. If the growth plate has been injured, a doctor may notice that this “empty space” is longer on one side of the bone than on the other. Small cracks in the bone around the growth plate may also indicate a growth plate injury.

An X-ray can also show a fracture in another part of the bone or signs of a sprain or strain, both of which often cause symptoms similar to those of a growth plate injury.

CT Scan

Some injuries to the growth plate may not be obvious on an X-ray. If your child has tenderness near a growth plate but an X-ray does not show signs of an injury, the doctor may order a CT scan to determine the cause of the symptoms.

CT scans use a series of X-rays to create detailed images of parts of the body. With a CT scan a doctor may be able to see whether cartilage in the growth plate has started to harden into bone—an indication that the growth plate may be closing too early as a result of injury. A CT scan may also provide a better view than an X-ray of small bone fractures that could be causing your child’s symptoms.

MRI Scans

MRI uses magnetic fields and radio waves to produce detailed images of areas that are difficult to see on X-rays, including subtle fractures or bone “bruises”—areas of increased water in the bone. Although these bone bruises may be associated with a growth plate injury, they can also occur without a growth plate injury and cause similar symptoms. If the growth plate has been injured, an MRI can be useful in identifying portions of the cartilage in a growth plate that have started to harden into bone.

Some people feel claustrophobic in an MRI machine. If your child’s doctor recommends an MRI, a child life specialist can explain the procedure to your child and provide distraction while the scan takes place. Child life specialists are therapists who are responsible for helping children to feel comfortable during diagnosis and treatment and to understand what is happening. Our doctors can also administer a light sedative so that a child can sleep through the MRI procedure.

Our doctors use the results of these tests to assess whether a growth plate injury has occurred and, if so, what treatment it requires.