Ilizarov Technique
Lengthening bone
Callus Distraction

What is bone transport? 

There are occasions when an existing bone is abnormally short, stunted, or insufficient in size.  Trauma (like a crush injury), tumour, bone infection, non-unions, a prematurely stunted growth cycle, and birth defects are common ways for a bone to develop or become abnormal in size.  When this occurs, it may be desirable to consider lengthening or repositioning the bone.  

You can lengthen bone?  

Yes, it's possible to lengthen bone. 

The most well-known technique is by grafting (attaching bone or bone-like material to the bone to be lengthened).  But other techniques exist, too.  There are synthetic materials that can be formed and inserted into the body to act like bone.  A bone can be cut and repositioned in a longer orientation.  And an adjacent less-important bone can, at times, be moved into place to replace a bone loss in a more important bone.

Each such case is highly unique, of course.  The surgeon must consider what bone-and what part of that bone--is involved.  And the surgeon must fully appreciate the orientation of the abnormally formed bone, what the symptoms are, and what needs to be accomplished.  

This topic, therefore, is much to complicated to fully discuss this topic, so on this web page, we'll simply discuss a relatively new way to lengthen a bone, and give you an example.

What is Callus Distraction? 

The callus distraction technique (or Ilizarov technique, as this procedure was first invented by a Russian doctor named Ilizarov. The Ilizarov technique involves attaching a highly stable external fixator (a metal brace that attaches to the outside of the body) that holds the concerned bone in a very stable position.  The bone is then cut and allowed to begin healing--where the two opposing bones growing towards each other.  (This newly-formed bone between the cut surfaces of bone is called "bone callus", and is not to be confused with a callus on the skin).  

But these two bones aren't allowed to heal together fully.  Just before the two surfaces attach, the two fragments are pulled slightly apart by the adjustable external fixator.  

The bone edges once again grow towards each other, and just when they are almost attached again, they are again pulled apart.  This can be done again and again until the bone is at the desired length, at which time the bone fragments are finally allowed to heal fully.

Originally, the technique was used to lengthen large bones, but the technique has been refined and adapted for use in the small bones of the feet.  

How quickly does the bone lengthen? 

Techniques vary, but the bone is typically lengthened 4 times per day.  These four adjustments adds up to a total lengthening of 1 mm per day.  Depending upon how much you need to lengthen the bone, this will give you an idea as to how long the procedure takes.  (You must add one week before beginning to lengthen the bone and six to eight weeks to the total to allow the bone to heal fully at the end.)