Banged my thumb. started to swell. put ice on it. now it is a little swolled and discolored. how do i know if it is just a bruise or not!

X Ray: If you have any of these signs: - Swelling - Deformity of the thumb - Significant pain - Inability to move your thumb - Tingling - Change in color of the thumb ...then it is important to get an X Ray done to rule out an underlying fracture

Xray: Will tell you if you have a nondisplaced fracture or not although it won't necessarily make it feel any better to know with that right diagnosis is you'll have a better expectation about if anything needs to be done or what the timeframe is for your thumb to feel better. Most nondisplaced fractures don't need anything more than a small splint or some tape if they're on the fingertip.