Ectopic accessory finger-like appendage

What it means

In contrast to forms of polydactyly where the supernumerary digit (this can either be a rudimentary or a completely 'normal' digit) is either located postaxial (on the ulnar side of the hand, next to the little finger), preaxial (on the radial side of the hand, next to the thumb) or mesoaxial (somewhere central, between thumb and little finger), a supernumerary digit may also be placed ectopically, meaning anywhere else except post-,meso- or preaxial. In the literature this is sometimes referred to as Disorganisation-like Syndrome (OMIM223200).

Rare diseases that can present with this1

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category