Diagnostic value of MRI in traumatic triangular fibrocartilage complex injuries: a retrospective study.

Background: Triangular fibrocartilage complex (TFCC) injuries commonly manifest as ulnar-sided wrist pain and can be associated with distal radioulnar joint (DRUJ) instability and subsequent wrist functional decline. This study aimed to assess the diagnostic value of MRI compared to wrist arthroscopy in identifying traumatic TFCC injuries and to determine the distribution of different TFCC injury subtypes in a normal clinical setting.

Methods: The data of 193 patients who underwent both preoperative wrist MRI and wrist arthroscopy were retrospectively reviewed. The analysis focused on the proportion of subtypes and the diagnostic value of MRI in traumatic TFCC injuries, utilizing Palmer's and Atzei's classification with wrist arthroscopy considered as the gold standard.

Results: The most prevalent subtype of TFCC injuries were peripheral injuries (Palmer 1B, 67.9%), followed by combined injuries (Palmer 1 A + 1B, 14%; Palmer 1B + 1D, 8.3%). Compared with wrist arthroscopy, the diagnostic sensitivity, specificity, negative predictive value (NPV), and Kappa value of MRI was as follows: traumatic TFCC tears 0.99 (95% CI: 0.97-1), 0.90 (0.78-0.96), 0.97 (0.87-1), and 0.93; styloid lamina tears 0.93 (0.88-0.96), 0.53 (0.30-0.75), 0.47 (0.26-0.69), and 0.44; and foveal lamina tears 0.85 (0.74-0.92), 0.38 (0.29-0.49), 0.79 (0.65-0.89), and 0.21.

Conclusions: The diagnostic value of MRI in traumatic TFCC injuries has been confirmed to be almost perfect using Palmer's classification. In more detailed classification of TFCC injuries, such as pc-TFCC tears classified by Atzei's classification, the diagnostic accuracy of MRI remains lower compared to wrist arthroscopy. Radiological associated injuries may offer additional diagnostic value in cases with diagnostic uncertainty.