Two-dimensional Ultrasound Combined With Shear Wave Elastography In Chronic Ankle Instability Of The Lateral Collateral Ligament

Objective:To investigate the value of 2D ultrasound combined with shear wave elastography(SWE)in patients with chronic ankle instability(CAI),and to investigate the relationship between 2D ultrasound and shear wave elastography in the lateral collateral ligament of the ankle joint in CAI patients and healthy controls.This study will analyse the incidence of ligament injuries in the lateral collateral ligament of the ankle in CAI and the changes in the ligaments on the healthy and affected sides,to investigate the application of SWE technology in the study of lateral collateral ligament injuries in the ankle,and to provide a new diagnostic and assessment tool for clinical diagnosis and treatment.Methods:Patients with lateral collateral ligament injury of the ankle who visited our hospital from December 2020 to December 2022 for acute sprain of the ankle and long-term ankle discomfort were selected and included in this experiment according to their long-term medical history,clinical indications,inclusion and exclusion criteria consistent with unilateral chronic ankle instability(CAI),and were divided into two groups A and B according to their status at the time of consultation,group A being the unilateral CAI group and group B being the unilateral CAI with The two-dimensional ultrasound and elastography examinations were performed with a Supersonic Aixplorer(France)ultrasound diagnostic instrument to observe the structural echogenicity of the ligaments,the ligament alignment and the surrounding tissue echogenicity in the twodimensional ultrasound images of the patients.The mean values of ligament size and Median mean elasticity(Emean)were recorded for the healthy controls and patients in Group A in the stressed and unstressed positions of the limbs bilaterally.The Emean and shear wave velocity(SWV)were recorded in the natural position of the bilateral limbs of patients in group B.The ligament ratios(ligament stress length/ligament non-stress length)and Emean of the healthy limb in group A were compared with those of the healthy control group,and the ligament ratios and Emean of the healthy and affected limbs in group A,and the Emean and SWV of the healthy and affected ligaments in group B were analyzed.The ROC curves were plotted to calculate the optimal cut-off values for shear wave elastography to diagnose lateral collateral ligament injury in patients with CAI,and to evaluate the diagnostic value of SWE technique for lateral collateral ligament injury in patients with CAI.Results:1.General clinical data of all CAI patients compared with the healthy controls:age and BMI were statistically significant(P<0.05),and gender was not statistically significant(P>0.05).2.The Emean and ratio of the lateral collateral ligament were not statistically significant(P>0.05)in the healthy side of group A compared to healthy controls,and the ratio and Emean were statistically significant(P<0.001)in the affected side of patients with group A compared to the healthy side,with an increased ratio on the affected side and a decreased Emean on the affected side compared to the healthy side.3.In the comparison study of group B patients on the healthy side,it was found that:(ⅰ)the difference between type Ⅰ injury and the healthy side was statistically significant(P<0.001),and Emean and SWV decreased compared with the healthy side;(ⅱ)the difference between type Ⅱ injury and the healthy side was statistically significant(P<0.001),and Emean and SWV decreased compared with the healthy side.(ⅲ)Type Ⅲ injury versus the healthy side,with a statistically significant difference(P<0.001)and a decrease in Emean and SWV compared to the healthy side.(ⅳ)Type Ⅰ,Ⅱ and Ⅲ injuries were all statistically significant differences when compared to the healthy side,and Emean and SWV decreased in that order.4.Analysis of the injury ratio of each ligament revealed that the anterion talofibular ligament was the ligament with the highest injury ratio among all ligaments,and injury to the heel-fibular ligament was more likely to occur with injury to the anterior talofibular ligament and less likely to occur alone.5.Diagnosing CAI with parameters related to the SWE technique revealed that The best cut-off value for Emean in group A was 115.5 kPa,with a sensitivity of 93.3%and a specificity of 91.1%;the best cut-off value for Emean in group B was 111.6 kPa,with a sensitivity of 91.7%and a specificity of 92.9%.The best cut-off value of Emean in group B was 111.6 kPa.It shows that SWE technology has high diagnostic value in the diagnosis of chronic ankle instability.Conclusions:1.Age and BMI are influential factors in the occurrence of CAI.2.The lateral collateral ligament of the ankle in the healthy limb of patients with unilateral CAI does not differ from that of healthy individuals.3.It is feasible to apply the SWE technique to assess CAI lateral collateral ligament injuries.In CAI with acute injury,the Median mean elasticity of typeⅠ injury,type Ⅱ injury and type Ⅱ injury decreased sequentially,and SWE can be used as an effective adjunctive diagnostic technique for injury typing.4.The incidence of anterior talofibular ligament injuries is highest in patients with CAI,and injuries to the heel-fibular ligament tend to occur in combination with injuries to the anterior talofibular ligament.Type Ⅰ injuries are more likely to occur in CAI with acute injury.