Someone’s hands are tied: Someone is not able to help or intervene.And more commonly used in Spoken English: “My hands are tied” , which means “you are not free to behave in the way that you would like for some reasons”（无能为力,束手无策）. This is usually used when you are too busy or when you have something else to do.
Etymology: This metaphor became common after the mid-seventeenth century. An early appearance in print was in clergyman Thomas Fuller’s The Holy State and The Profane State (1642): “When God intends a Nation shall be beaten, He ties their hands behind them.”
中文释义：这个短语用来描述状况紧急，但已用尽所有可行的办法，实在无计可施的情况。比如在职场中，我们难免有无奈的时候，这时我们可能就需要拒绝别人，渲染一种心里很想帮、但实在帮不了的感觉。如：You know I would help you if I could, but right now, my hands are tied. （你知道，如果可以，我会帮你的，但是我现在束手无策。）