his face grew pale and his thoughts so alarmed him that his hips gave way and his knees knocked together.
KJV
Then the king’s countenance was changed, and his thoughts troubled him, so that the joints of his loins were loosed, and his knees smote one against another.
ASV
Then the king’s countenance was changed in him, and his thoughts troubled him; and the joints of his loins were loosed, and his knees smote one against another.