Musculoskeletal ImagingE1006. MRI of the Triangular Fibrocartilage Complex: Cross-Sectional Anatomy and Injury Classification
Zhan H1, Li W2, Bai R1, Qian Z1, Yin Y.3 1. Beijing Jishuitan Hospital, Beijing, China; 2. Peking Union Medical College, Beijing, China; 3. Radiology Associates, Corpus Christi, TX
Address correspondence to H. Zhan (email@example.com)
Objective: Our aim is to investigate if the high-resolution 3T MRI can demonstrate the complex anatomy of the triangular fibrocartilage complex (TFCC) and provide accurate diagnosis of TFCC injuries.
Materials and Methods: Fourteen cadaveric wrists, 20 healthy volunteers, and 86 surgically proven TFCC-injured patients were included in this study. All subjects had wrist MRI. MR arthrography was performed on one cadaveric wrist. Subsequently, all 14 cadaveric wrists were sliced into a 2-mm-thick slab with a bandsaw, six in coronal plane, four in sagittal plane, and four in axial plane. The MRI features of normal TFCC were analyzed in 20 healthy volunteers and 14 cadaveric wrists along with 86 TFCC-injured patients according to Palmer classification.
Results: Triangular fibrocartilage (TFC) was a low-signal disk-like structure best observed on coronal images. The palmar and dorsal radioulnar ligaments were best evaluated in the transverse plane. The ulnotriquetral and ulnolunate ligaments were best visualized in the sagittal plane, and these two structures could be better demonstrated on MR arthrography. According to Palmer classification, 69 patients were Palmer injuries (52 had traumatic tear and 17 had degenerative tears). Seventeen patients whose injuries could not be classified according to Palmer classification included 13 with volar or dorsal capsular TFC detachment and four with horizontal tear of the articular disk.
Conclusion: High-resolution 3T MRI can show the complex details of the TFCC anatomy and can demonstrate the pattern and the extent of TFCC injuries. Traditional Palmer classification described the most common TFC injuries; with high-resolution 3T MRI, more injuries of this type can be found including horizontal tear of the TFC and capsular TFC detachment.