Magnetic Resonance Imaging of the Triangular Fibrocartilage Complex.

The imaging evaluation and interpretation of the triangular fibrocartilage complex (TFCC) is both challenging and rewarding for the radiologist and surgeon alike. The TFCC comprises a complicated group of fibrocartilaginous and ligamentous structures at the ulnar aspect of the wrist that plays an important role in wrist biomechanics. It is the main stabilizer of the distal radioulnar and ulnocarpal joints and functions to distribute compressive forces at the ulnocarpal joint during axial loading. Derangement of the TFCC is the most common source of ulnar-sided wrist pain. Imaging plays an important role in the diagnosis and management of these lesions. The TFCC can anatomically be divided into proximal and distal parts to emphasize the role that the proximal TFCC has in stabilizing the distal radioulnar joint. Tears can be divided into traumatic and degenerative categories using the Palmer classification. Further subclassification based on the location for traumatic tears and the degree of derangement in degenerative tears guides clinical management. The vascular anatomy is important in determining management options for various lesions. A detailed understanding of the normal anatomy of the TFCC, imaging limitations and pitfalls, the Palmer classification system, and current treatment options is critical to the accurate and clinically useful interpretation of radiologic examinations of the TFCC.