The Ilizarov fixator is an orthopedic device used to stimulate bone growth and lengthen and straighten limbs. It may also be used to treat complex and/or open bone fractures or in cases of infected non-union of bones that are unresponsive to other techniques. The apparatus was named after its inventor, Gavriil Abramovich Ilizarov, an orthopedic surgeon. The Ilizarov fixator uses the principle of separating bone to stimulate new bone growth (distraction osteogenesis).
The Ilizarov apparatus is a cylindrical metal external fixator that consists of struts, rings, and wires. The structure of the Ilizarov apparatus helps to both immobilize and relieve stress from fracture sites. The fixator functions by transferring force through the top and bottom rings of the outer frame into the solid healthy bone while bypassing the fracture site.
- Treatment of bone infections
- Dwarfism – to increase the length of the extremities
- Poliomyelitis – to lengthen the limb and correct deformities
- Acute fractures, mal-unions, and non-unions
- Correction of both congenital and acquired limb deformities
- Comminuted or segmental limb fractures
- Lengthening of foot and limb stumps
The Ilizarov method is a minimally invasive procedure that fixes deformity or fracture corrections in three phases.
Phase 1: Operative
In a procedure known as “transosseous osteosynthesis”, Kirschner’s wires are passed through the skin and bone of the limb that is to be modified. The wire’s protruding ends are then attached to the external rings with special ‘wire fixation’ bolts. Thin threaded strut are then used to connect and fix the rings to one another. Following this, a corticotomy or osteotomy (cutting of the bone) is performed to stimulate osteogenesis (formation of new bone).
Phase 2: Distraction
The distraction phase typically begins 10 days after the operative phase. The patient is given instructions for making adjustments to the Ilizarov fixator by turning the nuts on the rods four times a day to stimulate the growth of new bone. The phase’s turning schedule continues until the deformity is corrected at which point the apparatus is locked.
Phase 3: Consolidation
This phase begins after the apparatus is locked and consists of allowing the newly formed bone to solidify over a course of about 2-3 months. When the bone solidifies, the Ilizarov apparatus is removed and a cast is applied to the limb for protection while the bone continues to heal. The patient is mobilized initially for partial weight bearing and later for full weight bearing with support.
- Incision-free technique results in low incident rates of infections, hemorrhages, and tissue trauma when compared to traditional methods.
- The cylindrical shape of the apparatus enables correction of the deformities in 3-dimensions simultaneously enhancing the versatility of the fixator.
- No immobilization means the patient can move throughout the treatment reduces the possibility of contractures and joint stiffness problems.
- Short-term inpatient hospitalization.