Re: DISTRACTION OSTEOGENESIS

[sushantpatel_doc]

Techniques
Using exclusively an external fixator

The most common is the Ilizarov surgery with the Ilizarov external fixator. Other external fixators are Wagner, Orthofix and Judet. Dr. Helong Bai (8th Hospital in Chongqing, China) developed the technique "Micro-wound" with a different apparatus.
[edit] Ilizarov surgery
Main article: Ilizarov apparatus
Ilizarov.jpg

Ilizarov surgery, developed by Gavriel Ilizarov, a Russian orthopedic surgeon, in 1951, is the oldest and most common method of distraction osteogenesis. It often brings complications while some new methods have a much lower rate of complications.

The process involves the following:

* Shattered bones and devascularised ones are removed from the patient, leaving a gap;
* The healthy part of the upper bone is broken into two segments with an external saw;
* The leg is then fitted with the Ilizarov frame that pierces through the skin, muscles, and bone;
* Screws attached to the middle bone are turned 1 millimetre (mm) per day, so that new bone tissues that are formed in the growth zone are gradually pulled apart to increase the gap (One millimetre has been found to be the optimal bone distraction rate. Lengthening too fast overstretches the soft tissues, resulting not only in pain, but also in the inability of the bone to fill up the gap; too slow, and the bone hardens before the full lengthening process is complete.);
* After the gap is closed, the patient continues to wear the frame until the new bone solidifies; the waiting period is usually 120 days before the leg can be used.

Ilizarov surgery is extremely painful, uncomfortable, infection-prone, and often causes unsightly scars. Frames used to be made of stainless steel rings weighing up to 7 kilogram (kg), but newer models are made of Carbon fiber reinforced plastic, which though lighter, are equally cumbersome.

Derivative devices provide physicians better control over the bone axis and angle during elongation, such as the Taylor Spacial Frame (TSF) which is computer assisted. The downside of these developments are their relative complexity and resulting longer learning curve.

For decades, the Ilizarov procedure was the best chance for shattered bones to be restored, and crooked ones straightened. Breakthroughs in distraction osteogenesis in the 1990s, however, have resulted in less painful (albeit more expensive) alternatives, such as unilateral rails.