The study focuses on the choice of prevention schemes of the appearance and recurrence of gangrene of the lower extremities, depending on any of the degrees of confidence that the patient will have gangrene or will experience its relapse. The degree of confidence is determined using the fuzzy logic of decision making on the relevant membership functions. For each of the selected classes, an appropriate prevention scheme has been developed, the effectiveness of which was tested using the theory of measuring latent variables and the synthesis of mathematical models of their choice depending on the degree of risk of the occurrence and recurrence of lower extremities gangrene. Model statistical tests showed that compared with traditional prevention schemes the use of the proposed models can increase the rate of positive results in the absence of lower extremities gangrene and reduce the possibility of relapse (recurrent changes by 42%, risk of amputation by 35%).