A Radiographic Dye Method for Intraoperative Evaluation of Syndesmotic Injuries.

BACKGROUND: The Chertsey test has been recently defined as an intraoperative test for the detection of the syndesmotic injuries by the application of intra-articular contrast. However, no study has investigated the reliability and comparative analysis of the Chertsey test. The purpose of this study was to explore the diagnostic accuracy of the Chertsey test in predicting syndesmosis instability of the injured ankle, with correlation to preoperative computed tomography (CT) findings.

METHODS: A total of 39 patients who were operated on due to the unilateral ankle fracture and had no complaint on the contralateral ankle joint were included in the study. An intraoperative Chertsey test was performed on all ankle fractures and bilateral ankle CT was obtained preoperatively. Ankles were classified as Chertsey +, Chertsey -, and contralateral control group. The morphology categorization, width, and volume of the syndesmotic region were measured on axial images of the CT. Mann-Whitney U test was used to compare the data. Intraobserver and interobserver agreements were accessed by calculating the intraclass correlation coefficient (ICC) for radiologic parameters and the Chertsey test.

RESULTS: The Chertsey test was positive in 13 (33.3%) of 39 ankle fractures. Patients with a positive Chertsey test showed a significant increase in syndesmotic width and volume compared with Chertsey - and control group. However, there was no significant difference between Chertsey - and the control group. All the ICC values were excellent for both radiologic measurements and test.

CONCLUSION: The Chertsey test is a reliable and useful test that can be used intraoperatively in the diagnosis of syndesmotic injuries.

LEVEL OF EVIDENCE: III, comparative series.