Sympathetic chain clipping for hyperhidrosis is not a reversible procedure.

Background: Many techniques have been used to treat palmar hyperhidrosis. Compensatory sweating is a difficult adverse effect. Clipping has been proposed because of its supposed reversibility when clips are removed at a later date. The primary aims of this article are to investigate the neuronal lesion of the sympathetic chain caused by clipping and to study the possibility of regeneration after removal of the clips.

Methods: We performed an experimental study at the Minimally Invasive Surgery Centre Jesus Uson in Caceres (Spain). We used a swine model, performing clipping, unclipping, and extirpation of different segments of sympathetic chain with clips and after clip removal, following a chronogram of 10, 20, and 30 days. Pathologic studies of specimens and statistics were done at the University of Seville.

Results: Ten days after clipping, all sympathetic chains displayed evident Wallerian degeneration. Twenty days after clipping, Wallerian degeneration of myelinated fibers was more widespread and also more striking. Thirty days after clipping, a very marked macrophagic reaction was visible, with multiple signs of phagocytosis of myelin debris. By 30 days post operation and 20 days after clip removal, a few residual myelin and amyelinated fibers were visible. These findings suggest that axon regeneration is not possible.

Conclusions: There are Wallerian degeneration and axon loss 10 days after clipping. The almost total absence of myelinated and amyelinated fibers following clip removal suggests that there was no nerve regeneration, and that therefore clipping cannot be considered a reversible technique.