New insights into the anatomy at the palmodigital junction in Dupuytren's disease: the palmodigital spiralling sheet.

The anatomy in the region of the palmodigital junction has been relatively little studied, but it is very relevant for the surgical treatment of Dupuytren's disease. To study the microanatomy of the palmodigital junction, we dissected 26 cadaveric digits from 13 human cadaveric hands using microsurgical techniques. The dynamics of the different ligaments were studied in three hands preserved by Thiel's method. We found a structure, which we propose to name the 'palmodigital spiralling sheet' (PSS), which has not been described before. It has a spiralling course around the neurovascular bundle giving rise to a neurovascular tunnel distally in the palm of the hand. It is formed proximally by fibres from the pretendinous band and the intrinsic muscle fascias and distally is in continuity with Cleland's and Grayson's ligaments. As such it connects the palmar and digital fascias. Its spiralling course stabilizes the neurovascular bundle in the healthy hand, but can displace it in Dupuytren's disease, which may contribute to the development of spiral cords.