Fig. 4

Diversity and taxonomic analysis in the healthy male, quadriplegia (PU) and paraplegia (PL) SCI groups. a Sobs index of rarefaction curves for the healthy male, quadriplegia and paraplegia groups of samples based on OTUs detected using a similarity threshold of 97%. b Significant differences in the genus chao index (b) and Simpson index (c) were observed between the three populations (p < 0.05). d ANOSIM/Adonis of beta-diversity analysis revealed significant differences in the structure of the gut microbiota among the three groups (p = 0.001, r² = 0.233) at the phylum level. e PLS-DA revealed that there were significant differences in bacterial community composition between the three groups at the OTU, phylum and genus levels (PU and PL represent patients with quadriplegia and paraplegia, respectively)