Growth plates are areas of cartilage found at the ends of long bones. They play a role in the bone growth of children and teens. An injury to a growth plate can affect the development of a bone.

While you may not think it, bone is actually living, active tissue that changes constantly throughout your lifetime. Even as you read this, your body is replacing old or damaged bone tissue to help maintain bone strength and integrity.

Bone development is particularly prominent during your childhood and teenage years, a time when your body is still growing. Growth plates are important for bone growth during this time.

This article covers what you need to know about growth plates and the role they play in bone growth. It also discusses the prevalence and effect of growth plate injuries and what you can do to prevent them.

Growth plates are an area of cartilage found at each end of a long bone. Specifically, they’re located between the end of the long bone (epiphysis) and the widened part of the long bone shaft (metaphysis).

Your long bones are bones that are longer than they are wide. This type of bone is found in your:

  • arms and forearms
  • legs
  • fingers
  • toes

The activity of your growth plates slows near the end of puberty. When it stops completely, typically in your early twenties, the growth plates are replaced by solid bone.

What factors affect the age of growth plate closure?

A 2020 study found that growth plate closure in adolescents and young adults is influenced by:

  • Sex steroids (oestradiol): complete closure occurs approximately 2 years earlier in girls than in boys
  • Puberty development: growth plate closure correlated with physical maturation
  • Body mass index (BMI): growth plates closed earlier for people with obese or overweight (potentially due to increased adipose tissue and its associated hormones)
  • Nutrition: dietary intake of protein and minerals is essential for the development of bones and growth plate closure

The study also found that physical activity did not influence growth plate closure.

The activity in the growth plates during childhood and adolescence causes your long bones to elongate at each end.

Cartilage cells in the growth plates are organized into three specific zones. Each zone plays a different role in bone growth.

Resting zone

The resting zone is located closest to the epiphysis, which is the end of the long bone. It’s where precursor cells develop into cartilage cells that will eventually enter the next zones of the growth plate and contribute to bone growth.

Precursor cells lose the ability to develop into cartilage cells as growth plate closure approaches.

Proliferative zone

The proliferative zone is the middle zone of cartilage cells. In this zone, cartilage cells are quickly growing and dividing.

Hypertrophic zone

The hypertrophic zone is found closest to the long bone shaft. Within this zone, cartilage cells have become enlarged up to 20 times their original size.

Cartilage cells in the hypertrophic zone gradually begin to age and die off, after which they’re replaced with bone tissue. This extends the length of the bone. Blood vessels also form around the new bone tissue.

How do growth plates affect height?

Simply put, growth plates affect height by making your bones grow longer. As your bones grow longer, you become taller.

A variety of factors, including but not limited to hormones, nutrition, and inflammation, can affect the activity of growth plates. As such, these factors can potentially affect your height.

For instance, nutritional deficiencies may alter growth plate activity, resulting in a smaller stature. In another example, an excess of growth hormone can lead to increased growth and a larger stature.

Because they are made up of cartilage and are located at the ends of bones, growth plates are more prone to fractures. In fact, research suggests that growth plates are five times weaker than nearby ligaments.

This means if trauma occurs around the joint, an injury is likely to occur in the weakest section, which is the growth plate.

Growth plate fractures can happen due to accidents, falls, and injuries while playing sports or engaging in activities like cycling or skateboarding. They can also occur from overuse, such as in younger children who are baseball pitchers, distance runners, and gymnasts.

The potential symptoms of a growth plate fracture are:

  • persistent pain near the end of a bone
  • trouble putting pressure on the affected area, such as limping
  • a visible deformity or distortion close to the end of a bone
  • swelling, tenderness, and warmth in the affected area

Because of the role of growth plates in bone growth and development, these fractures require prompt treatment. This is because delays in medical attention could lead to limbs that are crooked or different lengths.

The type of treatment used depends on factors like:

Many growth plate fractures can be treated by applying a cast. However, more serious fractures may require surgery.

In addition to fractures, there are also other injuries and conditions that can affect growth plates.

Little League elbow and shoulder

Little League elbow and shoulder are two types of overuse injuries that can affect growth plates in the elbow or shoulder. They cause persistent pain in the affected area that worsens with certain motions, such as throwing.

  • Little League elbow happens due to repeated overhead arm motions and is most common in sports like baseball, tennis, and volleyball.
  • Little League shoulder typically occurs due to repeated throwing motions, such as throwing a baseball.

Osgood-Schlatter disease

Osgood-Schlatter disease happens when the growth plate at the top of your shinbone becomes irritated due to repeated activity. This leads to knee pain and sometimes a bony bulge below the knee cap.

Osgood-Schlatter disease tends to affect teens who participate in sports that include a lot of running and jumping like soccer, tennis, and basketball. It can affect one or both legs.

Sever disease

Sever disease is when the growth plate in your heel becomes irritated and inflamed. It causes heel pain that gets worse with activity. It’s linked with sports that include a lot of running or jumping, like soccer, basketball, and track and field.

Some factors that boost the risk of Sever diseases in children or teens include excessive physical activity, running on hard surfaces, and wearing worn-out or unsupportive shoes.

Slipped capital femoral epiphysis

is when a fracture or injury occurs in the growth plate of the femoral head, causing it to slip off the neck of the bone at the growth plate. The femoral head is the rounded, uppermost part of your thigh bone that fits into the socket in your pelvis to form the hip joint.

SCFE usually develops during periods of rapid growth in adolescents, between the ages of 12 and 16 in boys, and 10 and 14 in girls. It may also occur after a minor fall or trauma to the area.

SCFE is a serious injury that usually requires surgery. It can result in osteonecrosis of the hip joint.

There are several steps that can be taken to help prevent growth plate injuries in children and teens. These include:

  • warming up and stretching before engaging in physical activity
  • resting when exhausted or in pain
  • using training techniques that are appropriate for young, growing athletes
  • protecting the area around your joints with equipment, such as elbow guards in baseball, shin guards in soccer, and padding in football
  • replacing any footwear or equipment when it becomes old and worn out
  • ensuring proper nutrition to boost bone health
  • avoiding high-energy trauma that can occur from jumping on a trampoline

If you think your child has had a growth plate injury, seek medical attention. Prompt treatment can help prevent future issues with bone growth and development.

Growth plates are areas of cartilage at the ends of long bones that play a role in bone growth. Your growth plates are active during childhood and adolescence. They close after you’re done growing and are replaced by solid bone.

Because they’re more brittle than surrounding bone and connective tissue, growth plates are more prone to injury. Growth plate injuries need to be treated promptly to prevent problems with bone growth in children and teens.

You can take steps to prevent growth plate injuries. These include warming up and stretching properly, resting if you’re tired or in pain, and using appropriate training techniques and equipment.