Prospective Study on the Diagnostic Accuracy of 4D CT for Diagnosing Instable Scapholunate Dissociation (ACTION)

Zielsetzung Early detection of instable scapholunate ligament (SLL) tears is essential to prevent osteoarthritis. Arthroscopy has since been the diagnostic gold standard because non-invasive methods have failed to exclude instable injuries reliably. This prospective study aims to determine the diagnostic accuracy of dynamic 4DCT of the wrist for diagnosing instable SLL tears compared to our previous standard method cineradiography as referenced by arthroscopy.

Material und Methoden Prospective study including 40 consecutive patients with suspected SLL tears diagnosed using 4DCT scans interpreted by two independent radiologists. For comparison a historical cohort of 78 patients who were diagnosed using cineradiography were analyzed retrospectively. All patients underwent arthroscopy of the wrist. SL joints with and SL distance of>3 mm were interpreted as unstable. Interrater reliabilities (IRR) of wrist kinematics were calculated and compared for 4DCT and cineradiography.

Ergebnisse In the 4DCT group 33 patients showed unstable SLL tears intraoperatively, whereas in the historic cohort arthroscopy revealed 63 unstable SLL tears. The sensitivity of 4DCT was lower than for cineradiography in detecting unstable SLL tears (73% vs. 83%). Specificity of 4DCT was comparable to cineradiography (83% vs. 80%). The positive predictive value was high (96% vs. 95%) for both methods. The separation value with optimal sensitivity and specificity was 2,275 mm for 4DCT and 2,925 mm for cineradiography increasing sensitivity to 79% and 89% respectively. IRR tended to be higher for 4DCT compared to cineradiography.

Schlussfolgerungen 4DCT can detect unstable SLL tears which present with SL gaps wider than 2.2 mm during imaging with a sensitivity of 79% and a specificity of 83%. Diagnostic accuracy was higher for cineradiography in a historical cohort. This might be attributed to the shorter acquisition time. 4DCT since wrist kinematics can be studied with a high reliability on 4DCT scans.

Publikationsverlauf

Artikel online veröffentlicht:
13. April 2023