Use Your Crutch However You Want, But ...

​When using one crutch (or cane, etc.) because one side is injured, it’s typically most helpful to use that one crutch on the non-injured side since arms swing opposite legs. Meaning, with normal gait, when your right foot goes forward, your left arm goes forward. Unweighting the injured side by putting some weight through a crutch on the opposite side thus ensures that you move as biomechanically normal as possible - which is important not only with respect to walking as efficiently as possible, but also in preventing other problems from walking like this. If your right lower extremity is injured and you use a crutch on your right arm then you’ll have to lean/sway much more to the right than you would normally. It’s also awkward and inefficient because you’ll have to move your right arm forward simultaneously with your right leg, which, as I pointed out, is unnatural.
​-- Laura