Odd question but

[momof3heathens]

Are people allowed to try on things like knee braces before buying? Can't afford to make a mistake with sizing.

[Natalka]

I suppose it might depend where, but I would think so.

Often you can get braces right at the place where you are doing physio - either at a hospital or a centre, and for sure they will let you try them.
When my husband got wrist braces, the exact same ones were cheaper at SDM than at the physio place, so he bought them there and was able to try them on before buying.

[barbis9]

Are people allowed to try on things like knee braces before buying? Can't afford to make a mistake with sizing.

A decent medical supply store should allow you to try them before you buy. Keep the receipt as you can claim it as a medical expense on your income tax.