Mapping of referred sensation after targeted reinnervation surgery in the lower limb

To address the lack of sensation that accompanies limb loss, an increasing number of amputees are receiving a nerve transfer surgery, Targeted Reinnervation (TR). Touches at the surgery site can feel as though they originate in the amputated (phantom) limb. However, sensory recovery after this surgery is not well understood, particularly in the lower limb. We have developed a protocol for mapping the nature and extent of referred sensation in the lower limb, evaluated on a single participant that has undergone TR surgery. Of 25 sites surveyed, consistent referred sensation was identified in 4 areas, one of which appeared to be dependent on the pose of the phantom limb. Understanding the capability for referred sensation to the lower limb has enormous potential for the restoration of intuitive feeling.