Growth Plate injuries

From Elizabeth Quinn, Your Guide to Sports Medicine.

What Is the Growth Plate?
The growth plate, also known as the physis, is the area of developing tissue near the end of the long bones in children and adolescents. Each long bone has at least two growth plates: one at each end. The growth plate determines the future length and shape of the mature bone. When growth is complete-sometime during adolescence-the growth plates are replaced by solid bone.

Who Gets Growth Plate Injuries?
These injuries occur in children and adolescents. The growth plate is the weakest area of the growing skeleton, weaker than the nearby ligaments and tendons that connect bones to other bones and muscles. In a growing child, a serious injury to a joint is more likely to damage a growth plate than the ligaments that stabilize the

An injury that would cause a sprain in an adult can be a potentially serious growth plate injury in a young child.

Most injuries to the growth plate are fractures. Growth plate fractures comprise 15 to 30 percent of all childhood fractures. They occur twice as often in boys as in girls, with the greatest incidence among 14-year-old boys and 11- to 12-year-old girls. Older girls experience these fractures less often because their bodies mature at an earlier age than boys'. As a result, their bones finish growing sooner, and growth plates are replaced by stronger, solid bone.

Growth plate fractures occur most often in the long bones of the fingers (phalanges), followed by the outer bone of the forearm (radius) at the wrist. These injuries also occur frequently in the lower bones of the leg: the tibia and fibula. They can also occur in the upper leg bone (femur) or in the ankle, foot, or hip bone.

What Causes Growth Plate Injuries?
While growth plate injuries can be caused by an acute event, such as a fall or a blow to the body, they can also result from overuse. For example, a gymnast who practices for hours on the uneven bars, a long-distance runner, or a baseball pitcher perfecting his curve ball can all have growth plate injuries. Whether an injury is acute or due to overuse, a child who has pain that persists or affects athletic performance or the ability to move or put pressure on a limb should be examined by a doctor. A child should never be allowed or expected to "work through the pain."

Children who participate in athletic activity often experience some discomfort as their bones and muscles grow and they practice new movements. Some aches and pains can be expected, but a child's complaints always deserve careful attention. Some injuries, if left untreated, can cause permanent damage and interfere with proper physical growth.

Although many growth plate injuries are caused by accidents that occur during play or athletic activity, growth plates are also susceptible to other types of injury, infection, and diseases that can alter their normal growth and development.

Diagnosis and treatment

How Are Growth Plate Fractures Diagnosed?
After learning how the injury occurred and examining the child, the doctor will probably use X rays to determine the type of fracture and decide on a treatment plan. Because growth plates have not yet hardened into solid bone, they don't show on X rays. Instead, they appear as gaps between the shaft of a long bone, called the metaphysis, and the end of the bone, called the epiphysis. Because injuries to the growth plate may be hard to see on X ray, an X ray of the noninjured side of the body may be taken so the two sides can be compared. In some cases, other diagnostic tests, such as magnetic resonance imaging (MRI), computed tomography (CT), or ultrasound, will be used.

What Kind of Doctor Treats Growth Plate Injuries?
For all but the simplest injuries, the doctor may recommend that the injury be treated by an orthopaedic surgeon, a doctor who specializes in bone and joint problems in children and adults. Some problems may require the services of a pediatric orthopaedic surgeon, who specializes in injuries and musculoskeletal disorders in children.

How Are Growth Plate Injuries Treated?
As indicated in the previous section, treatment depends on the type of fracture. Treatment, which should be started as soon as possible after injury, generally involves a mix of the following:

Immobilization
The affected limb is often put in a cast or splint, and the child is told to limit any activity that puts pressure on the injured area. The doctor may also suggest that ice be applied to the area.

Manipulation or Surgery
In about 1 out of 10 cases, the doctor will have to put the bones or joints back in their correct positions, either by using his or her hands (called manipulation) or by performing surgery. After the procedure, the bone will be set in place so it can heal without moving. This is usually done with a cast that encloses the injured growth plate and the joints on both sides of it. The cast is left in place until the injury heals, which can take anywhere from a few weeks to several months for serious injuries. The need for manipulation or surgery depends on the location and extent of the injury, its effect on nearby nerves and blood vessels, and the child's age.

Strengthening and Range-of-Motion Exercises
These treatments may also be recommended after the fracture is healed.

Long-Term Followup
Long-term followup is usually necessary to monitor the child's recuperation and growth. Evaluation may include X rays of matching limbs at 3- to 6-month intervals for at least 2 years. Some fractures require periodic evaluations until the child's bones have finished growing. Sometimes a growth arrest line may appear as a marker of the injury. Continued bone growth away from that line may mean that there will not be a long-term problem, and the doctor may decide to stop following the patient.