Mr Bailey also made artificial arms, which could be useful for the Venus de Milo here if she should suddenly notice the fact that curvature of the spine is the least of her worries.
Invisible crutches were intended to the keep the shoulders up - the top part fitted under the arms and there was a steel attachment that fixed into the stays. The pictures below show the difference made to the posture by such contraptions i.e. not enough to be worth the effort.
Source: Health and beauty : or, woman and her clothing considered in relation to the physiological laws of the human body, Caplin 1864