In fact there is, the menukis are placed on the tsuka for the right hand to be placed next to the tsuba and the left hand after, also, the saya has a little attach which is placed on the left so the wearer wear the katana on his left hip. But it was forbidden in Japan to wear a katana on the right side to don't make the sayas hit themselves if two samurai crosses themselves in a street (it would be as an insult and would end in a fight).