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
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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.

Correcting the majority of congenital craniofacial defects, as well as some facial injuries resulting from trauma, requires making bones longer. Distraction osteogenesis is an effective way to grow new bone, but it is much more difficult to accomplish in the face than in other areas of the body. Bones must often be moved in three dimensions, as opposed to just one, as in a limb, and scarring must be kept to a minimum. Researchers are attempting to improve the distraction devices used in the face. Until recently, the mechanisms were external and only operated along straight lines. Now, maxillofacial surgeons can use curvilinear devices capable of moving bone in three dimensions.

These new devices still need to be improved. They depend on patient caretakers reliably turning a screw. The next goal is to create devices that will move bone continuously, not in daily increments of 1 mm. These continuously moving devices would cause less pain, wouldn’t require daily patient compliance, and might promote faster bone growth. At the moment, researchers are testing a continuously moving device in animal models, and they have found that the device’s components are durable, that its user interface works, and that it is tolerated by the body. When the position sensor in the device is perfected, the device will be ready to use in people.

In distraction osteogenesis procedures involving the face, it is critical that bone movements be carefully planned before a device is implanted. No existing device is capable of changing its trajectory mid-course, and small skeletal changes lead to large changes in the structure of the face. Recently researchers have developed state-of-the-art software capable of simulating the entire process of distraction osteogenesis. The 3-D planning tool uses data from CT scans to create a segmented model of the patient’s skull, and it then calculates the vector of movement required to achieve desirable bone positioning. Outcome CT scans can be overlaid on the original model to assess the effectiveness of the procedure. In the future, researchers hope that the distraction devices used in maxillofacial procedures will continue to improve, along with the corresponding software