Objective: The purpose of this study, with wrist arthroscopy as the reference standard, was to assess the usefulness of MRI in the detection of tears of the radioscaphocapitate and long radiolunate extrinsic carpal ligaments.
Materials and methods: The cases of 26 patients consecutively registered from 2003 to 2009 who underwent wrist arthroscopy and wrist MR arthrography at our institution were identified. MR images were read by a musculoskeletal radiologist blinded to the arthroscopic findings. Operative reports and arthroscopic photographs were examined for descriptions of the radioscaphocapitate and long radiolunate ligaments. Ligaments were classified as intact or torn in all studies. With arthroscopy as the reference standard, sensitivity and specificity were calculated for both the radioscaphocapitate and the long radiolunate ligaments.
Results: Radioscaphocapitate and long radiolunate tears were diagnosed with MR arthrography in 50% and 31% of the 26 cases and arthroscopy in 31% and 31% of cases. With arthroscopy as the reference standard, the sensitivity of MR arthrography in the detection of radioscaphocapitate and long radiolunate tears was 63% and 25%; the specificity was 56% and 67%.
Conclusion: With currently established imaging criteria, correlation between MR arthrographic and wrist arthroscopic findings in the assessment of tears of the radioscaphocapitate and long radiolunate ligaments is inconsistent. Because of the increasing clinical importance ascribed to the extrinsic carpal ligaments, further work aimed at refining both imaging techniques and diagnostic criteria in the MRI evaluation of these structures is warranted to improve correlation with results obtained at arthroscopy.