Role of Direct MRI Arthrography by Combined Distal Radioulnar and Radiocarpal Compartment Contrast Injection Over Conventional MRI in Detection and Differentiation of Triangular Fibrocartilage Complex Injuries.

BACKGROUND: Wrist pain is a prevalent and diagnostically complex issue, often stemming from subtle injuries to the triangular fibrocartilage complex (TFCC). Due to the small size and intricate structure of the wrist ligaments, conventional MRI may not reliably detect all TFCC tears, especially peripheral or partial injuries. Direct magnetic resonance arthrography (MRA) has emerged as a superior imaging modality by improving contrast resolution and visualizing joint integrity more precisely. OBJECTIVE: To evaluate the diagnostic value of direct MR arthrography using combined radiocarpal (RC) and distal radioulnar (DRU) joint contrast injection compared to conventional MRI in detecting and characterizing TFCC injuries. METHODS: A prospective cross-sectional study was conducted on 73 patients (aged 20-43) presenting with chronic wrist pain at Ain Shams University and Misr Radiology Center from January 2023 to December 2024. All patients underwent conventional MRI, followed by direct MRA using combined RC and DRU contrast injection. Arthroscopy was performed as the gold standard. RESULTS: Conventional MRI identified TFCC tears in 30.14% of patients, while direct MRA detected them in 61.64%. When validated against arthroscopy, conventional MRI yielded a sensitivity of 45.65%, specificity of 96.30%, and overall accuracy of 64.4%, with a Kappa value of 0.354 (fair agreement). Conversely, direct MRA demonstrated a markedly higher sensitivity (95.65%), specificity (96.30%), PPV (97.78%), NPV (92.86%), and overall accuracy of 95.9%, with a Kappa value of 0.913 (excellent agreement). Peripheral TFCC tears (Palmer 1b) were the most prevalent subtype (30.14%). Additional pathologies such as scapholunate ligament injuries (48.65%) and ECU tenosynovitis (18.92%) were frequently detected. CONCLUSIONS: Direct MRA using combined compartment injection is highly accurate and superior to conventional MRI in diagnosing TFCC injuries. It should be considered an essential imaging tool for evaluating chronic wrist pain and planning surgical intervention.