HOW LIMB LENGTHENING WORKS – BRACES, REHABILITATION, AND BONE HEALING

What is limb lengthening and correction of deformities?

The processes of limb lengthening and correction of deformities require surgical intervention. When a bone breaks, it naturally regenerates to heal the fracture. Lengthening involves separating the bone and very slowly moving the bone segments apart so that new bone can form in the resulting gap. As the bone segments are slowly pulled apart, the bone regenerates, leading to its lengthening.

Types of stabilizers used in limb lengthening

The device used for limb lengthening is called a stabilizer. The Paley Institute uses various types of stabilizers, which can be divided into two categories: external stabilizers and internal stabilizers, or growth nails.

External fixators are devices attached to the bone using wires and pins. They act as a scaffold, supporting the separated bone and mechanically lengthening the limb.

Internal stabilizers, or telescopic intramedullary nails, are implanted into the medullary cavity and controlled using an external ERC remote control. The remote control rotates a magnet inside the nail, which drives the screw mechanism, extending the telescopic rod.

Stages of the lengthening process – stretching and consolidation

The lengthening process consists of two stages: the distraction phase and the consolidation phase. During the procedure, an osteotomy is performed, followed by the placement of a stabilizer. After the procedure, most patients stay in the hospital for a day or two, and rehabilitation begins the day after the procedure.

Stretching begins a few days to a week after surgery. The rate of stretching is approximately 1 mm per day, but this may vary depending on the tolerance of the bone and soft tissues. Patients and their families learn how to adjust the external fixator or operate the ERC remote control in the case of the PRECICE nail.

Rehabilitation and physical therapy during limb lengthening

Patients typically begin physical therapy after being discharged from the hospital. It is a key part of the process and should be done daily. Most patients attend therapy five times a week and do exercises at home on the weekends.

Continuing exercises at home is crucial to the success of limb lengthening. The more active the patient is, the better the functional outcome. Physical therapy during limb lengthening differs from rehabilitation following other orthopedic surgeries. As the limb lengthens, the muscles become increasingly tight and joint range of motion is restricted, which may give the impression that the patient’s condition is worsening.

Monitoring bone healing and completion of treatment

Once the desired limb length has been achieved, the bone enters the consolidation phase. The lengthening device remains in place until the new bone has fully hardened. The total duration of wearing the device is approximately 1 month for every centimeter of lengthening in children and 1.5–2 months (or longer) in adults.

Bone healing is monitored with monthly X-rays. Once the medical team determines that the new bone is strong enough, the brace is removed during a minor outpatient procedure.