Staff 
January 25, 2014Depends. Everyone has a one leg that is longer than another, but often the difference is so small its not necessarily detectable. Obviously, if a large amount, there is probably going to be problems due to the changes in alignment of the spine and other parts of the body. Obviously if the difference is a miniscule amount, its probably not going to be a problem. Where the debate and discussion is just where is the cut-off point is as to if the difference is clinically significant or not. Some people think a few millimeters is important; yet others think that its not important until it at least a few inches. It is also going to depend on activity levels. A few millimeters might be important if you run marathons. A few inches is not going to be important is you lead a sedentary lifestyle. There is very little research to guide this process. More information is certainly needed to base decisions on.