Blount disease, is a disorder of the tibia, or shin bone. It causes the lower leg to turn inwards, much like a bowleg. The difference is, however, that bowlegs may straighten out, but Blount disease will continue to get worse if there’s no treatment. Blount disease is also called tibia vara. While Blount disease can be idiopathic (born with it) or acquired, this article focuses on the idiopathic type.
Usually, treatment of Blount disease is the same, regardless of what type it is. Surgeons fix the tibia to stabilize it with hardware. But, there are drawbacks to the surgery. Once the surgery has been completed, there’s little room for revision or correction if it’s needed, and there are many complications that could occur, in addition to the usual surgical problems. These include damage to the nerves (nerve palsy), uneven leg length, return of the problem, and so on.
For doctors or families that don’t want surgery performed, there are other methods, such as putting a wire brace around the leg and in the bone to stretch it into place (external fixation) and bracing. These treatments need a lot of cooperation from the patient and family though. The authors of this article wanted to review studies that looked at treatment of Blount’s disease to see if one was better than the other.
After searching the medical literature for pertinent studies, the researchers evaluated the studies that they’d found. The studies all had varying approaches. One group of 12 studies looked at acute correction. One small study (by Rab) compared 6 tibia and their correction with screw and casting. Another larger one of 23 tibia (by Hayek) looked at surgery for initial correction with external fixation, and so on. The second, smaller group of studies (four) looked at gradual correction. One study of 20 tibias (by de Pablos) looked at correction with a one-sided frame, while another larger study of 69 tibias (by Alekberov) looked at gradual correction with a circular frame, for example.
One problem with many studies like this is the size. When a study is low in numbers, it’s difficult to provide accurate conclusions. Blount disease isn’t a common disorder, so it may not be possible to do a large study. Another critique of these studies was the follow-up time of the patients was too short, leaving it impossible for the researchers to learn of the long-term outcomes.
Not all is lost though. Regardless of the type of treatment chosen, the complication rate was low, even among the patients who had surgery to remove part of the bone (osteotomy).
The authors admit that the best type of study would be a trial where people are enrolled specifically for the trial and then randomized to treatment (put in one group or the other). But, as mentioned earlier, the disease isn’t common and the length of time plus substantial follow up may be just too long to accomplish this.
After looking at the available studies, the authors concluded that there was little difference between the outcomes of patients who had acute correction compared with those who had gradual correction.