Gait examination in catatonia using 3D optical markerless motion tracking

Background: Three-dimensional (3D) markerless motion capture (MoCap) systems are emerging as powerful tools for the objective assessment of sensori-/psychomotor abnormalities in mental disorders. However, the application of 3D-MoCap technology for gait analysis in catatonia remains unexplored. Methods: This study included 23 patients with and 53 patients without catatonia, classified according to ICD-11. Catatonia severity was assessed using the Northoff Catatonia Rating Scale (NCRS) and the Bush-Francis Catatonia Rating Scale (BFCRS). Gait was examined via a 3D markerless MoCap system, Salpêtrière Retardation Rating Scale (SRRS), the Unified Parkinson's Disease Rating Scale (UPDRS), and the Heidelberg Neurological Soft Signs Scale (NSS). Results: Principal component (PC) analysis of spatiotemporal gait parameters revealed four principal components, accounting for 51.98 % (PC1), 23.46 % (PC2), 7.98 % (PC3), and 6.3 % (PC4) of the total gait variance. PC1 was primarily characterized by time-dependent features such as cycle time and stance time, while PC2 predominantly captured space-dependent features, including stride length and stride width. PC1 was significantly reduced in the catatonia group (p < 0.05); however, it was not significantly associated with catatonia severity. Total scores and gait-related subitems of the SRRS and UPDRS scales differed significantly between the catatonia and non-catatonia groups (p < 0.05, corrected). Conclusion: The results of this study demonstrates for the first time that 3D markerless MoCap can effectively quantify gait in catatonia, revealing alterations in temporal and spatial gait dynamics. Future research should explore the longitudinal effects of catatonia treatment on gait patterns and investigate potential biomarkers for disease monitoring.