Thumb polydactyly with a floating Ulnar Thumb

Thumb Polydactyly is reported to be the most common congenital anomaly of the hand in Japan. T floating type is not particularly rare, accounting for 0.9 to 15% of all cases of thumb polydactyl However, to the best of our knowledge, there has been only one case of thumb Polydactyly with floating ulnar thumb, reported by Onizuka. Herein, we report a case very similar to that reported I Onizuka. In our case, the vessels feeding the floating ulnar thumb branched from the superficial pi mar arterial arch, and X-rays revealed triphalangism. In surgery, we not only reconstructed tl morphology of the thumb, but also tried to preserve the sensation in the reconstructed thumb by transposing the digital nerve of the floating ulnar thumb to the radial thumb. In addition to thumb polyda tyly, our case also showed hypoplasia of the thenar muscles.