Upon amputation, not only do amputees lose the mobility of their missing limb, but they also lose all sensory capabilities associated with that limb. This makes it difficult to perform routine tasks, such as walking up and down stairs or simply feeling the sensation of touch. However, with the recent development of Targeted Reinnervation surgery, there is now the potential for more advanced prosthesis that incorporate sensory feedback.
Targeted Reinnervation (TR) surgery involves rerouting the nerves from the amputated limb into neighboring muscle groups that remain intact. When the amputee contracts the muscles of their missing limb, the rerouted nerves continue to receive signals and cause the new muscle groups to contract. These contractions have been used to design more functional and efficient prosthesis. An interesting discovery resulting from TR surgery was that upon touching the skin sites of the rerouted nerves, amputees were able to feel sensations from their missing limb. Little exploration has been done in this field, but by designing prosthesis that provide sensory feedback, amputees will begin to incorporate their prosthetic into their body schema and subsequently the use of their artificial limb will feel more natural.
Related study: The Plasticity of Tactile Perception