The epiphyseal plate or growth plate is a cartilaginous or strong elastic section at the tip of the long bones of the body. Located in the metaphysis, the broader portion on each end of the bone, these sections allow the bones to lengthen as the body develops. Without this plate the body would be unable to grow taller. Epiphyseal closure or the stoppage of bone growth occurs between the ages of eighteen and twenty-five.
During development, the cells that make up the epiphyseal plate continually divide through a process called mitosis where the cell transforms into another identical cell. As these cells mature, they shift towards the mid portion of the bone called the diaphysis allowing for the process of redesign to continue at the epiphyseal plate. Once the body reaches maturity, all the cells responsible for new bone growth ossify or solidify into bone and this progression stops, thus bringing on epiphyseal closure. At this time the plate transforms into the epiphyseal line, the only remnant of the growth process.
When problems occur with the epiphyseal closure of a bone or bones, changes in the body’s structure or height can be evident. For example, if epiphyseal closure occurs before full maturity is reached, normal height may not be attained. When closure does not occur, the long bones will continue to grow allowing the individual to surpass natural height. These abnormal changes can also affect the shape of the long bones and create irregular formation resulting in deformities.
Since the growth plate is the weakest area of the bone due to its ever-changing structure, when an injury or damage, such as a fracture or break, is sustained in the growth plate before epiphyseal closure, it can bring about a premature stoppage of the cell replication thus halting growth. This can result in one limb being shorter than the limb on the opposite side. Growth plate injuries may also cause the bone to curve or become crooked.
Another result of a growth plate injury before epiphyseal closure could be damage to the blood vessels which are responsible for supplying blood, oxygen and nutrients to the bones and the body. Nerves may also be affected by a change in body structure. Nerves may become pinched or squeezed due to the inflammation process trigger by an injury causing swelling to the surrounding area. The amount of damage that can occur with this type of injury is dependent upon the severity of the injury and the maturity level of the bones. Injuries sustained before epiphyseal closure at a younger age are more likely to produce permanent changes to the length and the structure of the bone.