Ilizarov Limb Lengthening

Ilizarov Limb Lengthening​ Overview

The Ilizarov method is a surgical procedure involving the application of an orthopedic external fixator to a limb in order to reconstruct, reshape, or lengthen bones (usually of the limb).

External fixation is a surgical procedure in which rods are screwed into the affected bone through an incision and then attached to a stabilizing structure outside the body.

In order to perform Ilizarov surgery, a special apparatus known as a “Ilizarov apparatus or Ilizarov fixator” is required. It is recommended in cases where other reconstruction techniques cannot be used.

The Ilizarov Apparatus is a set of external fixators consisting of rings (2-6), rods, adjustable nuts, and Kirschner wires (a type of orthopedic stabilization wire/pin).

Diseases treated with Ilizarov Method

Bone deformities can be treated with the Ilizarov technique. These deformities may result from a variety of causes, which include:
  • Traumatic events. For example mal-union fractures. As a result, the stress on the joint may not be distributed evenly across the joint, which can result in problems for the surrounding joints. It can also give the impression that the affected limb is shorter, causing the patient to walk with a limp.
  • Multiple ailments, including Blount’s Disease, Hypophosphatemic Rickets, and Enchondroma.
    • Blount’s Disease is a tibial growth disorder in which the lower leg curves inwards, resembling a bow leg. It is prevalent among young children and adolescents. Although the cause is unknown, it is believed that the weight’s effect on the growth plates may be to blame. Just below the knee, the inner portion of the shin bone does not develop normally. Blount’s disease worsens as the child ages, as opposed to bowlegs, which tend to straighten as the child grows.
    • Hypophosphatemic rickets is a disease in which the bones become extremely brittle and easily deformed due to low blood phosphate levels. This is almost always an inherited disorder characterized by a kidney abnormality that causes excessive phosphate to be excreted in the urine without being reabsorbed into the bloodstream. Phosphate, along with calcium, is required for the ossification process and is involved in bone formation.
    • Enchondromatosis, also known as Ollier’s Disease, is characterized by multiple enchondromas, benign masses of cartilage growing within bone, close to the growth plate cartilage. These enchondromas can result in a variety of defects, including skeletal deformity and limb length discrepancy, and increase the risk of pathological fractures.
  • Additional Ilizarov method applications include:
    • Osteomyelitis and nonunions infected with bacteria. The removal of infected bone and tissue (debridement) is a required surgical procedure for osteomyelitis patients. If large portions of bone must be removed, the patient must undergo either a bone graft or a bone transport procedure to avoid amputation.
    • Acute trauma applications. The Ilizarov method is a highly effective treatment for patients with multiple fractures or polytrauma.

Ilizarov Method Surgery

The patient will undergo surgery in order to attach the Ilizarov fixator to the affected limb. Using a drill, wires are passed percutaneously through the bone. The protruding ends of the wires are attached to metal rings that encircle the limb and are then tensioned to increase stability.
Then, a corticotomy is performed. The cortex of the bone is removed, while the periosteal and endosteal blood supplies remain intact. These are the most essential components for bone formation. After a delay of five to ten days, distraction is initiated by rotating the nuts on the metal rods 0.25 millimeters four times per day, for a total of 1 millimeter per day. In this space, osteogenesis occurs as the distraction continues. Once distraction has been stopped, the frame is left in place to allow the new bone to harden. Typically, one month is required per centimeter of new bone formation. Following this, the frame is extracted under general anesthesia.

Benefits of the Ilizarov Method

The Ilizarov method has many advantages over other limb reconstruction methods. One of the primary benefits of distraction osteogenesis is that it is effective in both mature and young bone, implying that treatment based on this principle is not limited to children but also works in adults.
The Ilizarov external circular fixator is a valuable tool for a variety of reasons:

  • The apparatus’s modular design allows the frame to be customized for each individual patient.
  • The circular nature of the frame improves stability and evenly distributes stress across the corticotomy and distraction gap.
  • The structure and strength of the frame allow for weight bearing throughout the treatment, which benefits the patient in terms of day-to-day mobility as well as helping to build muscle strength and prevent joint stiffness.
  • When the frame is applied to the limb during surgery, only wires connect the bones to the rings, and no other skin incisions are made, reducing the risk of bleeding, infection, and damage to the surrounding soft tissues.
  • It holds bone fragments together to allow them to unite when traditional methods of fixation are unable to provide adequate hold on the fracture fragments, and allows significant compression in the case of nonunions. This causes osteogenesis, which can be used to lengthen limbs or regenerate bone that has been removed due to traumatic loss, tumor, or infection, for example.