'Joints' in the Bible

And thou hast said: Thus said the Lord Jehovah: Woe to those sowing pillows for all joints of the arm, And to those making the kerchiefs For the head of every stature -- to hunt souls, The souls do ye hunt of My people? And the souls ye have do ye keep alive?

then the king's countenance hath changed, and his thoughts do trouble him, and the joints of his loins are loosed, and his knees are smiting one against another.