how do you know if you need to wear a knee brace?

With respect: The argument to use a device “just to be safe” is faulty.

1) How do you know that a device is going to help the problem?
eg. A sleeve-type knee brace can give a little lateral support to the surrounding tissues, but in no way cushions the cartilage from jumping on a hard floor.

2) What if the device actually aggravates the problem?
eg. Wearing a brace too often can lead to muscle wasting, which actually weakens the knee.

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