Figure 2

Unsupervised clustering analysis using synovial histopathological parameters identified two main clusters within the spondyloarthropathy cohort (n = 82). The dendrogram represents the 82 spondylarthropathy cases on the y-axis, classified according to their similarity for the histological parameters. The degree of similarity is represented as rescaled distance on the x-axis: when two samples are closely similar the distance will be small, whereas a rescaled distance of 25 represents a high degree of histological difference.