Cold intolerance following microsurgical replantation of finger amputations: A retrospective cohort study.

Purpose: Cold intolerance following finger amputation is a major postoperative complication. Although current evidence suggests decreased blood flow to digital peripheral vessels may be associated with cold intolerance, the underlying mechanism remains controversial. This study aimed to investigate the relationship between skin perfusion in affected fingers and the presence of cold intolerance.

Methods: A retrospective cohort study was conducted to evaluate patients who underwent finger replantation at two centers between 2008 and 2020. Demographic data were collected, and at least one of the following evaluative methods was used: the Semmes-Weinstein monofilament test (SW test), moving two-point discrimination (M2PD), contrast-enhanced computed tomography, or thermography.

Results: A total of 41 amputated fingers in 20 patients were assessed, with a mean follow-up period of 18.7 ± 12.1 months. Most injuries were located in Tamai zone 4 (n = 18, 43.9 %), followed by zone 1 (n = 9, 22.0 %), zone 2 (n = 9, 22.0 %), and zone 3 (n = 5, 12.2 %). The most common injury type was crush (n = 24, 58.5 %), followed by guillotine (n = 13, 31.7 %) and crush-avulsion (n = 4, 9.7 %). A significant difference was observed in the SW test (p = .047) and average vessel diameter (p = .047) between patients with and without cold intolerance.

Conclusions: Narrowed blood vessels and impaired SW test scores are associated with cold intolerance after finger replantation. Nerve injury may potentially contribute to abnormal vasoconstriction. Further studies are needed to elucidate the underlying mechanisms of cold intolerance.