The appearance of new phantom fingers post-amputation in a phocomelus.

We report the unusual case of a woman with right upper limb phocomelia who, post-amputation of her right hand following trauma, sprouted a phantom hand that contained five digits, including a phantom thumb and index finger that had been absent since her birth. These two phantom digits were initially half normal size, however, more than three decades later, with mirror visual feedback treatment, she was able to elongate them to normal length. This suggests that a hardwired representation of a complete hand had always been present in her brain, but inhibited by the presence of afferents from the phocomelic hand. Amputation of the phocomelic hand then led to disinhibition of this dormant representation, and the emergence of a phantom hand with five fingers, which was then further enhanced by false visual feedback from a mirror. The case powerfully demonstrates the interaction of nature and nurture in creating and sustaining body image.