CT scan versus Saline Load Test for Detection of Traumatic Shoulder Arthrotomy: A Cadaveric Study.

Abstract

Traumatic shoulder arthrotomy (TSA) is a rare injury that is commonly detected through saline load test (SLT). There are no studies that have studied the ability of CT scan to detect a TSA. The purpose of this study is to determine the ability of CT scan to detect a TSA and compare it to the SLT. Twelve cadaveric shoulders were included in the study. Before intervention, a CT scan was conducted to determine presence of intra-articular air. After confirmation that no air was present, an arthrotomy was made at the anterior or posterior portal site. A CT was obtained post-arthrotomy to evaluate for intra-articular air. Each shoulder then underwent a SLT to assess the sensitivity of SLT and the volume needed for extravasation. Twelve shoulders were included after pre-intervention CT scan. Six shoulders received an arthrotomy through the anterior portal and six shoulders received an arthrotomy through the posterior portal. After the arthrotomy, air was visualized on CT scan in eleven of the twelve shoulders (92%). All twelve shoulders demonstrated extravasation during SLT. The mean volume of saline needed for extravasation was 29 ml with a standard deviation of 10 and range of 18 to 50ml. CT scan is a sensitive modality (sensitivity of 92%) for detection of TSA. In comparison, SLT is more sensitive (sensitivity of 100%) and outperforms CT scan for the diagnosis of TSA in a cadaveric model. Further research is needed to solidify the role that CT imaging has in the diagnosis of TSAs.