Computed Tomography Scan versus Saline Load Test in the Detection of Traumatic Arthrotomies of the Ankle: A Cadaveric Study

Abstract

OBJECTIVE: To evaluate the sensitivity and ability of computed tomography (CT) scan for diagnosing traumatic ankle arthrotomies compared to that of the Saline Load Test (SLT). METHODS: Eleven cadaveric ankles were included in the study. Prior to intervention, a CT scan was obtained to confirm the absence of intra-articular air. Arthrotomies were created at the anterolateral, posterolateral, anteromedial, and posteromedial aspects of the ankle under fluoroscopic visualization. A post-arthrotomy and post-range of motion CT scan was obtained to evaluate for the presence of intra-articular air. Each ankle then underwent a SLT with 60 mL of saline, where volumes provoking extravasation were recorded. RESULTS: Out of the 11 included ankles, intra-articular air was detected in all eleven ankles by CT scan. All eleven also demonstrated extravasation of saline through the arthrotomy site during SLT. Thus, the sensitivity for both CT scan and SLT for detecting ankle traumatic arthrotomy was 100%. The mean volume of saline needed for extravasation was 7.7 mL, with a range of 3 to 22 mL and a standard deviation of 5.4. CONCLUSIONS: Given that CT scan was equally as sensitive to the SLT, this study presents good evidence that CT scan may be used for the detection of ankle traumatic arthrotomies.