What Is an Epiphyseal Fracture?

A fracture at one of the ends of a long bone in a growing child involving its growth plate is known as an epiphyseal fracture. Disks of cartilage near each end of an immature long bone allow the bone to grow. These areas of growing tissue, known as epiphyseal plates, harden as a child matures to adulthood. The growth plates in bones are the weakest areas of the skeletal structure and are prone to injuries called fractures. This type of fracture is sometimes referred to as a Salter fracture or a Salter Harris fracture.

The shaft of a bone is referred to as the diaphysis while the rounded portion on each end is called the epiphysis. Between these two areas lies a flared portion of the bone at each end called the metaphysis. An epiphyseal plate is located between the epiphysis and the metaphysis at each end of a long bone. Depending on what parts of the bone are broken, an epiphyseal fracture may be classified as one of five or six types of fractures.

Type I fractures involve complete separation of the epiphysis from the metaphysis. The break goes through epiphyseal plate, which remains attached to the epiphysis. Such a fracture typically requires immobilization and sometimes requires repositioning of the bone pieces if there is significant displacement. Assuming there is no interruption of the blood supply to the epiphyseal plate, it is likely that the bone will grow normally.

Fractures through the growth plate and metaphysis but not involving the epiphysis are classified as Type II fractures. These are the most common type of epiphyseal fracture. With immobilization and rest, and repositioning of the bone or growth plate if necessary, the fracture typically heals and strengthens over time.

A rarer fracture in which part of the epiphysis and growth plate are separated from the metaphysis is classified as a Type III epiphyseal fracture. Teenagers are most likely to suffer this injury. It usually occurs at the lower end of the tibia, which is one of the long bones located in the lower leg. Surgery is sometimes necessary for this more serious type of fracture. Still, if the blood supply is maintained to the separated portion of the epiphysis, chances for normal growth of the bone are still good.

Type IV fractures run through the epiphysis, the epiphyseal plate, and into the metaphysis. Surgery is usually needed for this very serious injury to perfectly align the bone pieces. If this alignment is not maintained perfectly during recovery, the outlook for proper bone growth is poor.

Compression fractures of the epiphyseal plate are rare and generally involve crushing of the end of the bone and the growth plate. This injury, classified as a Type V epiphyseal fracture, is associated with a poor prognosis, most typically resulting in premature stunting of growth. It is difficult to detect and often remains undiagnosed until a disturbance in normal growth becomes evident. Such fractures typically require surgical treatment and often require later corrective surgery as well.

Some classification systems add a Type VI epiphyseal fracture in which part of the epiphysis, epiphyseal plate, and metaphysis are completely missing. Such fractures are usually the result of trauma such as an accident with heavy machinery, a gun shot wound, and so on. As with Type V fractures, these fractures usually require surgical treatment and later reconstructive surgery. They also usually result in stunted growth.

Diagnosis of an epiphyseal fracture is not always straightforward. After examination of a patient, a doctor usually orders an X-ray of the affected area. A second X-ray of a comparable area that is not injured, such as the other elbow for example, may also be ordered for comparison purposes. In cases where findings from these X-rays are insufficient, further imaging may be called for such as computer-assisted tomography or magnetic resonance imaging.