Anatomical network analysis of the structural organization of human wrist bones

The bone architecture of the human wrist demonstrates close morphofunctional relationships, suggesting the structural complexity of this anatomical region. Currently, anatomical network analysis (AnNA) is widely used as a systematic biological approach to study anatomical structures. Based on network theory, AnNA allows the analysis of structural complexity using modularity. The aim of the study was to investigate the structural organization of human wrist bones using magnetic resonance imaging (MRI) and AnNA. The study included MRI data from the hands of 50 men and 50 women aged 40–50 years. AnNA were analyzed using the igraph package in the R environment. Connections were divided into two types: direct or structural (joint connections), indirect or functional (ligament connections). Regardless of the connection type, AnNA revealed a two-modular organization of the wrist: medial (triquetrum, pisiform, hamate) and lateral (trapezoid, scaphoid, lunate, trapezium, capitate) modules for structural connections; medial (lunate, triquetrum, pisiform, capitate, hamate) and lateral (trapezoid, trapezium, scaphoid) modules for functional connections. Functional connections demonstrated greater density and, consequently, a higher degree of morphological integration and modularity, whereas structural connections were characterized by greater network homogeneity. The high density of functional connections and their clustering coefficient confirm the close relationship between components and their role in modularity formation. In summary, this study, based on network models, reveals the modular organization of wrist bones, which varies depending on the type of relationship considered (structural or functional).