In first half of the twentieth century there were no uniform or standard procedure for limb lengthening and the surgeons from different parts of the world followed different procedures to achieve this end. It has been found that they could rarely achieve an enhancement of 3 cms in limb length even though they performed a series of very invasive surgeries.
Around this time a surgeon named Gabriel Ilizarov from Siberia put forward a new theory named law of tension stress which envisages the regeneration of new bones and tissues a few days after corticotomy. Corticotomy means cutting of a bone into two parts in which the medullary vessels remain intact. Based on this principle he developed a circular fixator consisting of tensioned wires which can be used for adding or removing stress to the bone under elongation. He successfully used this apparatus on thousands of patients and slowly it was spread to Soviet Union and in 1980 an Italian journalist was treated successfully by llizaravo. After this successful event llizaravo addressed an Italian AO conference and from then onwards this apparatus became the most effective and useful device to correct bone deformity and bone fracture.
The rings of this apparatus are connected to the opposite sides of the bone which is fractured or which is to be elongated. Corrections are done four times a day which helps the growth of the limbs by 1 mm per day. As suggested in his theory the bone grows between the portions which are kept very closely using the llizaravo apparatus. Thus over a long period of time this incremental increase of the length of the fractured bone accumulates and the required extension is obtained.
With the help of llizarov frames and crutches the patient can practice weight bearing and slowly the initial pain is lessened.