Growth plates, also known as epiphyseal plates, are areas of cartilage located near the ends of growing bones in children and adolescents. Growth plates are responsible for lengthwise bone growth. An injury to a growth plate can be very serious and requires prompt treatment by a doctor.
What are growth plates?
Growth plates are made up of cartilage tissue at each end of long bones in children and teens. The long bones in the body that contain growth plates include:
- Humerus (upper arm)
- Radius (forearm)
- Ulnar (forearm)
- Femur (thigh)
- Tibia (shinbone)
- Fibula (calf bone)
Growth plates determine the future length and shape of the mature bone. When growth is complete, which is typically around ages 16-18 for girls and 18-21 for boys, the growth plates harden into solid bone.
Growth plates are the weakest areas of the bone and are therefore vulnerable to injury. An injury to a growth plate can damage the area of developing cartilage.
How do growth plate injuries occur?
Growth plate injuries most often occur from an acute injury, such as a fall, twist, or blow to the limb. Examples include:
- Falling onto an outstretched arm
- Landing hard on the feet after a jump
- Twisting a knee when changing direction suddenly
- Direct blow to the limb during sports
Growth plate injuries can also develop gradually over time, such as with repetitive stress on the bones from sports like gymnastics and distance running.
The types of sports that most often lead to growth plate injuries include:
- Football
- Hockey
- Wrestling
- Basketball
- Baseball/softball
- Track & field events
- Gymnastics
Growth plates are particularly vulnerable to injury before they finish maturing, which is generally around puberty. Younger children who participate in sports designed for older age groups are also at increased risk.
What are the symptoms of a growth plate injury?
Common symptoms after injuring a growth plate may include:
- Significant pain in the affected limb
- Swelling and tenderness over the growth plate
- An inability to move or put weight on the injured extremity
- Joint stiffness, limited range of motion
- Visible deformity if the bone has fractured and become misaligned
- Bruising over the site of the injury
The child will likely complain of an acute onset of pain at the time of injury. Depending on the severity, there may be an audible crack at the moment of injury.
Types of growth plate injuries
There are different types of injuries that can occur at the growth plate region:
Growth plate fracture
This is a crack or break through the growth plate cartilage. It is the most common type of growth plate injury. Growth plate fractures occur in zones with high tensile forces, such as the knee, ankle, wrist, and shoulder joints. They are further classified based on the type of fracture pattern:
- Salter-Harris type I – Fracture goes through the hypertrophic zone of the growth plate, but does not extend into the bone.
- Salter-Harris type II – Fracture line goes through the growth plate and separates part of the epiphysis from the metaphysis.
- Salter-Harris type III – Fracture goes through the hypertrophic zone of the growth plate and continues vertically into the epiphysis.
- Salter-Harris type IV- Fracture goes through the growth plate, across the metaphysis and epiphysis.
- Salter-Harris type V – Crushing injury/compression of the growth plate.
Growth plate dislocation
The epiphysis separates or slips off the end of the bone metaphysis. This occurs due to extreme force and tension on the joint. Dislocations are more common in the radial head and neck fractures.
Growth plate contusion
This is essentially a bruise to the growth plate region from trauma. Microfractures can occur at the cellular level. There is pain and swelling without a visible fracture.
Overuse injury
Repeated microtrauma and stress to the growth plate causes inflammation and irritation. It can occur from repetitive motions in sports like gymnastics, track & field, and dance. Common overuse growth plate injuries include Osgood-Schlatter disease in the knee and Sever’s disease in the heel.
Are growth plate injuries serious?
Growth plate injuries require prompt treatment by a doctor. They can result in potential complications if left untreated, including:
- Premature growth plate closure – This stops bone growth, leading to limb length discrepancy or angular deformities.
- Bone bridge formation – Bones heal by forming bridge of bony tissue between the metaphysis and epiphysis. This can restrict bone growth.
- Limb length discrepancy – Uneven bone growth due to asymmetrical damage to the growth plates.
- Loss of joint motion – Arthritis, stiffness, loss of range of motion.
- Malunion – Healing in a shortened or angulated position.
- Neurovascular injury – From fragments of broken bone damaging nerves and blood vessels.
Young athletes are often reluctant to express their pain or seek medical treatment after an injury. But prompt evaluation and management of growth plate injuries is vital for the child’s health and future joint function. Untreated injuries risk complications that can lead to lasting disability.
How are growth plate injuries diagnosed?
If a growth plate injury is suspected, the doctor will take x-rays of the injured limb. X-ray images can identify fractures or dislocations involving the growth plate.
Sometimes a MRI may be ordered to further evaluate the injury. An MRI provides a detailed view of the soft tissues like cartilage, tendons, and ligaments that are not visible on x-rays.
The doctor will also check for joint instability, range of motion, and neurovascular status of the limb. Comparison to the uninjured limb may show differences in limb length or angular alignment.
How are growth plate fractures treated?
The treatment plan will depend on factors like the child’s age, injury location, and type of fracture pattern. The goals of treatment are to restore bone alignment, promote proper growth plate healing, and prevent complications like limb length discrepancies.
Here are the general treatment guidelines:
- Immobilization – Casting, splinting, or bracing the injury to stabilize the bones and allow healing. Immobilization duration ranges from 3-6 weeks on average.
- Reduction – Manipulating the bones or surgical fixation to restore proper alignment. This is done for fractures that overlay or have a gap.
- Physical therapy – Range of motion exercises help strengthen the muscles and regain flexibility after the immobilization period.
- Activity modification – Limiting sports and physical activity during the healing phase. A gradual return to activity will be guided by the doctor and physical therapist.
- Repeat imaging – Follow-up x-rays during the recovery process to check fracture alignment and healing.
Most uncomplicated growth plate fractures heal well with immobilization and time. However, certain severe fracture patterns may require surgery to implant pins or screws to stabilize the bone fragments. The hardware is generally temporary and removed once the growth plate is healed.
Growth plate fracture recovery time varies based on the location and extent of the injury. It can range from 4 to 12 weeks for the fracture to fully heal. The doctor will monitor progress with repeat clinical exams and x-rays. Full return to sports and activities is allowed once adequate healing is seen on imaging and the child regains normal strength, mobility, balance, and endurance.
How are other growth plate injuries treated?
Growth plate dislocations may require closed reduction maneuvers to relocate the displaced bone. Surgery can also fix accompanying injuries like torn ligaments. A period of immobilization in a cast or splint allows the injured area to heal.
For growth plate contusions or overuse injuries, treatment focuses on rest, ice, compression, and elevating the affected limb. Anti-inflammatory medication can help ease swelling and pain. Limiting activity and sports allows the growth plate time to recover without excess repetitive stress. Physical therapy also helps improve flexibility and strength. Severe cases may require immobilization for a period of time.
Can growth plate injuries affect bone growth?
Growth plate injuries do carry a risk of growth disturbance in the injured bone. The severity of growth issues depends on factors like the child’s age, location of damage, injury type, and whether the growth plate was penetrated.
Younger children who sustain growth plate injuries have more remaining growth potential compared to older kids nearing skeletal maturity. Injuries to growth plates near the ends of longer bones also have a greater effect on future bone length.
Specific types of fractures, like Salter-Harris type V compression or type III fractures extending through the epiphysis, have the highest incidence of subsequent growth arrest. Growth plate penetration is linked to progressive deformities like angular malalignment or limb length discrepancies as the bone continues to grow.
However, mild growth plate fractures often heal without complication. Follow-up until skeletal maturity allows monitoring of bone growth. Limb lengthening procedures are possible for significant limb length differences caused by damage to the growth plate.
Can growth plates heal fully after an injury?
Yes, it is possible for growth plates to heal fully after an injury, especially with prompt treatment. However, the recovery process takes time.
Healing potential is best when the growth plate fracture is anatomically reduced early. Immobilization helps stabilize the injury site for the healing period. Younger children also have greater remodeling capacity compared to those nearing skeletal maturity.
Even if the growth plate heals with a bony bar or irregularity, its impact on bone growth may be minimal. Some residual growth disturbance can often be compensated for with guided growth techniques.
During the healing phase, close follow-up is important to monitor bone alignment. Repeat x-rays at intervals can identify growth changes requiring intervention. If caught early, procedures like epiphysiodesis or physeal bar resection can help guide appropriate bone growth.
With proper care and rehabilitation, many growth plate injuries heal without lasting damage. However, significant growth plate damage can increase the risk of joint deformities, stiffness, or arthritic changes later in life.
Can you prevent growth plate injuries?
There are steps that can be taken to help prevent growth plate injuries in children and adolescents:
- Wear protective gear – Padding, splints, and braces safeguard the joints during sports and activities.
- Avoid overuse – Limit repetitive impact to the growth plates from sports like gymnastics and running.
- Strengthen muscles – Building muscle strength and flexibility helps support and stabilize the joints.
- Use proper form – Maintain correct posture and technique during athletic activities.
- Limit playing time – Take frequent breaks during sports to allow the body to rest.
- Good nutrition – A balanced diet provides nutrients needed for bone growth.
- Proper rest and recovery – Avoid overtraining that can lead to overuse injuries.
- Safe playground surfaces – Use shock-absorbing surfaces under playground equipment.
Coaches and trainers should also avoid aggressive training regimens until growth plates have closed. Parents can benefit from education on growth plate injury risks, prevention, and detection.
Conclusion
Growth plate injuries in children and teens require prompt care to avoid potential complications. Fractures, dislocations, and other trauma to the growth plates can impair bone growth and joint function if left untreated. While growth plate injuries can often heal fully with rest and immobilization, severe damage may affect limb length or alignment. Prevention through proper training, technique, and protective equipment is key. Growth plate fractures and injuries in skeletally immature young athletes warrant close follow-up until skeletal maturity to ensure the best outcome.
