The Value of the Distal Radioulnar Joint Effusion in Diagnosing Triangular Fibrocartilage Complex Tears on Magnetic Resonance Imaging.

Abstract

A retrospective study was conducted to evaluate the role of distal radioulnar joint (DRUJ) effusion in aiding the diagnostic accuracy of central triangular fibrocartilage complex (TFCC) tears on non-contrast MRI. 89 consecutive patients who had undergone wrist arthroscopy for ulna sided wrist pain in our unit were identified and their preoperative imaging reviewed. Two consultant musculoskeletal Radiologists independently reported the presence or absence of a DRUJ effusion and or a TFCC tear. The inter-observer variability was calculated using weighted Kappa tests. Two by two tables were constructed to calculate the sensitivity and specificity of reported TFCC tear or DRUJ effusion on MRI in correctly diagnosing central TFCC tears identified at arthroscopy. Sensitivity of MRI to report a TFCC tear was 0.56 and specificity was 0.79. Sensitivity increased to 0.89 if either a DRUJ effusion or TFCC tear were seen on MRI. When observed together, the presence of both a DRUJ effusion and a TFCC tear seen on the imaging lead to a sensitivity of 0.74 and PPV of 82% when compared to findings at arthroscopy. In the absence of both DRUJ effusion and TFCC tear, the specificity of MRI increased to 0.92. Agreement by the radiologists on the presence of DRUJ effusion was substantial (k value 0.67) and TFCC tear was moderate (k value 0.58). The presence of DRUJ effusion on MRI can further improve sensitivity of MRI in diagnosing central TFCC tears. The sensitivity of detecting a central TFCC tear on MRI scan when both a DRUJ effusion and a TFCC tear were seen (0.74) is comparable to rates demonstrated on MRA meta-analysis results (0.78). Furthermore, considering the absence of both a DRUJ effusion and TFCC tear seen on MRI is useful in excluding the presence of a TFCC tear at arthroscopy.