My freind has bought her daughters a hamster and the poor thing has only 3 legs. the missing leg seems to be trapped inside its skin as anyone lse seem this..
ps its seems very healthy otherwise and gets about OK
Get a vet to check it out, it maybe possible to operate, although if its ok in other way they may just say leave it.
However, if it is suffering then they will be able to do the right thing for it. Definitely tell the store where you bought it
although its not really their fault, but they may offer to replace it if you had to part with it.
They did take it back to the shop and bought another one but felt so soryy for it they took it home again so they now have 2 It is not in any pain and is a normal happy little hamster it even tries to walk on the hidden leg