The triangular fibrocartilage complex Unravelling the black box

The Triangular Fibrocartilage Complex (TFCC) is a crucial stabilizing structure in the wrist, composed of fibrocartilaginous and ligamentous components that provide distal radioulnar joint (DRUJ) stability, ulnocarpal stability, and axial load distribution. TFCC injuries are a common source of ulnar-sided wrist pain, yet diagnosing TFFC pathology and management remain challenging due to overlapping symptoms with other wrist pathologies and the wide differential diagnosis for the small anatomic region of the ulnar sided wrist, as well as inconsistencies in anatomical definitions, imaging interpretation, and biomechanical understanding.
This thesis provides a comprehensive investigation into the anatomy, development, imaging, and biomechanics of the TFCC across different life stages, with a particular focus on pediatric and adolescent populations. It addresses critical knowledge gaps by proposing a standardized anatomical definition, revealing considerable variation in TFCC morphology and signal intensity on MRI in healthy adolescents, and highlighting the potential existence of congenital disc perforations. In addition, this work demonstrates the feasibility of postmortem ultra-high-field MRI (7T) for visualizing fetal TFCC development in unprecedented detail, even following contrast staining for micro-CT. Furthermore, it explores the biomechanical interplay between ulnar variance, TFC thickness, and skeletal maturation, especially in relation to wrist-loading sports. These relationships may help identify individuals at greater risk for developing physeal injury or TFCC-related wrist pain, particularly in young athletes.