She volunteered to be fitted with the limb in 2006 after she got frustrated with a standard prosthetic, and thus became the first woman to receive a bionic arm, fitted with a pioneering surgical process called 'targeted reinnervation'.
So, the surgeons took nerves from her shoulder and embedded them under muscle in her chest, enabling her to control her hand's movement by thought via tiny electrical impulses.
However, after 4 months of her operation, she 'felt' hot water on her lost hand when it hit her chest while in the shower,
In fact, touching her chest, where the nerves have been transplanted, or applying heat and cold to it, gave her the sensation of pressure, warmth or coolness in her missing hand.
However, according to doctors at the Rehabilitation Institute of Chicago, which has developed the new procedure, the sensations are because they moved sensory as well as motor nerves from her shoulder to chest.
"We have rewired herm. We purposely directed her hand sensation nerves on to some chest skin, and it worked," the Telegraph quoted Dr Todd Kuiken of the Institute, as saying.
One of her colleagues, Paul Marasco, said that Mitchell experienced the same sensations when the same part of her chest was touched.
"She is like clockwork. Her sensations are very well established," he told ABC News.
The development has given hope of new improvements in prosthetics.