Bones provide the framework for our bodies, but how they increase in size during childhood and adolescence is a process many find curious. This growth occurs not uniformly throughout the bone, but at specific locations designed for lengthening. Understanding these growth centers helps clarify how our skeletal structure develops and matures over time.
What Are Growth Plates?
Growth plates, technically known as epiphyseal plates, are specialized areas of cartilage located near the ends of long bones in children and adolescents. These regions are responsible for longitudinal bone growth, allowing bones to increase in length.
Within the growth plate, cartilage cells continuously divide and multiply, with new cells pushing older ones towards the bone shaft. As these older cartilage cells mature, they gradually transform into hardened bone tissue through a process called ossification. This continuous cycle of cartilage production and bone formation enables bones to lengthen during the growing years. Growth plates appear as dark lines on X-rays because they are made of cartilage, which is less dense than bone.
Growth Plates in the Foot
Growth plates are present in the bones of the foot, playing a role in its development and final shape. The foot is a complex structure with many bones, and several of these, particularly the long bones, contain growth plates. These include the metatarsals, which are the long bones in the middle of the foot, and the phalanges, which are the bones of the toes.
Growth plates are also found in the ankle region, at the ends of the tibia and fibula, which contribute to the ankle joint and overall leg length. The heel bone, known as the calcaneus, also has a growth plate. These growth centers work together to facilitate the proper growth and development of the foot’s intricate structure during childhood and adolescence.
When Foot Growth Plates Close
The process of growth plate closure, or epiphyseal fusion, marks the end of bone lengthening and occurs as a child reaches skeletal maturity. During this process, the cartilage in the growth plate gradually hardens and is replaced by solid bone, becoming an epiphyseal line. Once a growth plate has closed, that particular bone has reached its final length.
The timing of growth plate closure varies among individuals and between genders. Growth plates in the hands and feet are among the first to close. In girls, most growth plates typically close between the ages of 13 and 15, while in boys, this usually occurs between 15 and 17 years. However, some growth plates, including those in the foot, can remain open slightly longer, with closure as late as 18-20 years.
Understanding Foot Growth Plate Injuries
Growth plates are less strong than the surrounding ligaments and tendons, making them a common site for injuries in children and adolescents. Injuries can occur from a single traumatic event, such as a fall or accident, or from repetitive stress. Sports activities are a common cause, particularly those involving running, jumping, or repetitive motions.
One common foot-related growth plate injury is Sever’s disease, which affects the growth plate in the heel bone and is often seen in active children between 8 and 14 years old. A growth plate injury has the potential to affect future bone growth, leading to issues like a shorter limb or angular deformities. Symptoms often include pain, swelling, tenderness, and difficulty bearing weight on the affected foot. Prompt medical evaluation is important if a child experiences persistent foot pain after an injury.