I don't think so, but not a native speaker. But nos is a pronoun, not an adjective, so it can't be right (I think!). And see AmineHadj;s response above...."los" is generally used in this case for the possessive adjective. If a possessive adjective was used, it wouldn't be nos, it would be nuestros.
Because that is the usage. Spanish speakers use the reflexive to indicate which "arms", and they don't use possesive adjectives nearly as often as english speakers. To the point that when translating the spanish it is wrong to translate "los" as "the" in this case. Spanish speakers venturing into english have to use our style.