Effects of lower thoracic sympathicotomy on plantar hyperhidrosis

BACKGROUND: The purpose of this study was to investigate whether performing lower thoracic sympathicotomy (LTS) from T10 to T12 affects plantar hyperhidrosis in patients with palmo-plantar (PP) or palmo-axillary-plantar (PAP) hyperhidrosis. METHODS: Between January 2015 and January 2020, all consecutive patients with primary hyperhidrosis who underwent bilateral thoracoscopic sympathicotomy and met the inclusion criteria were included. Sympathicotomy was performed using one of the following two methods: the conventional upper thoracic vs. expanded thoracic sympathicotomy. In the expanded thoracic sympathicotomy, we expanded the level of sympathicotomy ranging from R5 to R12 in addition to the conventional upper thoracic sympathicotomy (R3 or R4). In cases of the expanded thoracic sympathicotomy, we defined the LTS as a sympathicotomy of the levels ranging from R10 to R12, which are related to plantar hyperhidrosis. RESULTS: A total of 103 subjects with PP (71 cases) or PAP (32 cases) hyperhidrosis were included. Palmar or axillary hyperhidrosis in all patients were alleviated after sympathicotomy. There was no difference in sweating decrease or CH according to the hyperhidrosis types or sympathicotomy techniques. In addition, no-LTS was performed in 77 cases and LTS was performed in 26 cases. In the no-LTS group, there were 65 and 12 cases of low and high degrees of CH, respectively. In the LTS group, there were 22 and four cases of low and high degrees of CH, respectively. There was no significant difference in CH between the no-LTS and LTS groups (P=0.981). Improvement in plantar hyperhidrosis in the no-LTS group was observed in 29 of 77 cases, while improvement in plantar hyperhidrosis in the LTS group was observed in 16 of 26 cases. The addition of LTS lead to significant improvement in plantar hyperhidrosis (P=0.034). CONCLUSIONS: Performing LTS is a safe and feasible procedure that improved plantar sweating more so than it did in cases that did not undergo LTS. Therefore, we cautiously suggest that adding LTS helps in the treatment of plantar hyperhidrosis combined with palmar hyperhidrosis. Further studies on LTS are needed to validate these findings and will be helpful in establishing management guidelines.