Guided Growth: A Revolution in Pediatric Orthopedics – What Is the Hemiepiphysiodesis Method?

Limb deformities in children with skeletal dysplasias do not necessarily mean surgery is inevitable. Thanks to the controlled growth method, correction is possible without cutting the bone—all it takes is a small plate and time.

What is controlled growth?

A child’s bones grow in length thanks to growth plates—zones of active cell division located at the ends of long bones. In children with skeletal dysplasias, such as achondroplasia, pseudoachondroplasia, or hypoachondroplasia, these growth plates do not function properly—the bones may be shorter, more crooked, or bow-legged.

Guided growth is a method that harnesses this natural growth process in a controlled manner. Instead of correcting a deformity with a single bone cut, the orthopedic surgeon influences the direction of bone growth by selectively inhibiting growth on one side of the growth plate. The bone straightens itself—in accordance with the laws of biology and physics.

Hemiepiphysiodesis—a minor procedure, a major change

A technical tool for controlled growth is hemiepiphysiodesis. It involves placing a small metal plate on one side of the growth plate of the femur or tibia—where the bone is growing too rapidly and causing the limb to become misaligned.

The procedure is performed through incisions only about 5 millimeters long on each side. Depending on the type of deformity—genu varum (X-shaped legs) or genu valgum (O-shaped legs)—the plate is placed on the lateral or medial side of the bone. Correction is possible at the level of the femur, tibia, or both simultaneously, and in justified cases, even at the ankle joint or the proximal end of the femur near the hip.

What does the procedure itself involve, and what happens afterward?

Hemiepiphysiodesis is performed on an outpatient basis—the child returns home that same evening. Once postoperative symptoms have subsided, usually after two to three days, the patient can put full weight on the operated limb. This procedure does not require prolonged immobilization or hospitalization.

The time required to achieve correction is usually between one and a half and two years. The rate of correction depends on the child’s growth rate—the younger the patient, the faster the bone responds to the plate. Therefore, the child’s age and the type of dysplasia are key factors in treatment planning.

When is this method most effective?

Growth stimulation works only while the growth plates are active—that is, until skeletal growth is complete. This means that the therapeutic window is limited. In some patients with dysplasias, treatment should begin

as early as around age two or three, because deformities progress rapidly and may require several stages of correction throughout the entire growth period.

If the correction is not performed during the growth phase, the only option for correcting the deformity is an osteotomy—a procedure that involves cutting the bone and realigning it. This is a much more complex procedure that requires a longer period of rehabilitation and healing.

Who is this method for?

Hemiepiphysiodesis is used in patients with skeletal dysplasias who have developed varus or valgus deformities of the lower extremities. This is particularly true for children with:

• achondroplasia and hypoachondroplasia—the most common genetically determined forms of short stature

short stature,
• pseudoachondroplasia—in which limb deformities develop gradually during the first years of life,
• multiple epiphyseal dysplasia (MED)—in which abnormal formation of the epiphyses leads to limb axial deformities,
• diastrophic dysplasia—requiring multi-stage orthopedic correction starting in early childhood.
Eligibility for surgery requires an individual orthopedic evaluation that takes into account radiographic findings, growth rate, and the child’s overall health.

Why is early diagnosis so important?

The earlier dysplasia is diagnosed and treatment is planned, the more time there is for correction using the guided growth method. That is why early genetic and orthopedic diagnosis is so important—ideally before deformities become permanent and conservative management becomes insufficient.

Growth-guided treatment is one of the most significant advances in pediatric orthopedics in recent decades. A small plate inserted at the right time can replace extensive surgery and allow a child to grow—literally—straight toward independence.