Investigator Jeannie Crosby sends this image of an anatomical peculiarity, together with a link (now gone dead, sorry to say) to the web site where she found it.
For a possible explanation, see the medical report “Salvage of amputated digits by temporary ectopic implantation,” by J. Bakhack and colleagues at Institut aquitain de chirurgie plastique, reconstructrice et esth?tique, chirurgie de la main et microchirurgie in Bordeaux, France.