Influence Of Ultrasonic Signs On The Diagnosis Of Anterior Talofibular Ligament Injury By Different Senior Radiologists

BackgroundAnkle ligament injuries often occur during daily activities and sports.The anterior talofibular ligament(ATFL)in the lateral collateral ligament of the ankle is most vulnerable due to the mechanism of varus injury and anatomical location.The ligament injury classification determines its subsequent treatment options,and surgical treatment is only required clinically when the ATFL is completely torn.Patients with acute complete ATFL tears will develop chronic ankle instability if they are not treated promptly with surgery.For patients with chronic ankle instability,ATFL injury affects the choice of surgical approach to reconstruct ankle stability.Therefore,whether acute or chronic injury,accurate diagnosis of ATFL injury classification is essential.Ultrasound is a common method for the diagnosis of musculoskeletal system diseases,which can not only describe the normal structure and abnormal performance of ligaments,but also assess the integrity of ligaments and distinguish the deep and superficial structure of ligaments.According to the European Society of Musculoskeletal Radiology guidelines,ultrasound is the imaging modality of choice for the examination of ATFL.The latest clinical guidelines divide the course of ankle injury into three periods according to the time of injury:acute(injury within 1-2 weeks),post-acute(after 2 weeks to within 12 months),and chronic(1 year and more).In previous studies exploring the diagnostic level of ultrasound for ATFL injury,the sensitivity of ultrasound in the diagnosis of complete acute ATFL tears varies greatly(ranging from 60%to 87%),which may be related to the different experience level of radiologists and their subjective dependence.For chronic ATFL injury,the accuracy of ultrasound diagnosis was only 76%,indicating that radiologists do not know enough about chronic ATFL injury.Radiologists usually make a diagnosis of the degree of ATFL injury based on ultrasound signs,but the diagnosis process depends more on the experience level and subjective judgment of radiologists,and different radiologists have different degrees of understanding of ultrasound signs.In the past,some scholars summarized the ultrasound findings after ATFL injury to overcome the subjective dependence between different radiologists,but this study did not refine the ATFL ultrasound signs at different injury periods,and did not explore the differences in the ability of different senior radiologists to identify ultrasound signs and the level of diagnosing the degree of ATFL injury.Therefore,the aim of this study was to investigate the differences in the recognition ability of ultrasonographic signs of ATFL injury and the diagnostic ability of ATFL injury classification among different senior radiologists in order to improve the radiologists’ understanding and diagnostic level of ATFL injury..ObjectiveTo compare the differences in the diagnostic level of ATFL injury by ultrasound classification among different senior radiologists,and to further refine the ultrasound signs of ATFL injury,to explore the ultrasound findings of ATFL injury at different periods,to compare the recognition ability of different senior radiologists for ATFL ultrasound signs at different periods of injury,and then to improve the overall radiologists’ understanding of ATFL injury and classification diagnostic level.MethodsUltrasound two-dimensional static images were retrospectively collected from 178 patients who underwent ultrasonography and surgical treatment from January 2020 to October 2022.Signs were extracted and refined according to the ultrasound findings mentioned in previous studies(including ligament thickness,tension,echo changes,ligament fibrous structure display,and whether combined with avulsion fractures).Ultrasonography during ATFL injury can be divided into five types:normal,contusion,partial tear,complete tear,and ligament tear with scar hyperplasia.Four different senior radiologists(two senior radiologists SA and SB and two junior radiologists JA and JB)extracted the signs of ultrasound images and judged the type of ATFL injury.The diagnostic results of ATFL injury typing by the radiologists were compared with the gold standard surgical results to assess the differences in the level of ATFL injury typing diagnosis(accuracy,sensitivity,and specificity)by the radiologists.At the same time,the signs extracted by the two radiologists with the highest diagnostic level were selected as reference signs to compare the differences in the recognition ability of radiologists for ultrasound signs of ATFL injury.In order to better investigate the effect of the injury period on the diagnostic level of radiologists in the study,the combined post-acute and chronic periods were collectively referred to as the non-acute period.Results1.General informationA total of 178 patients were included in the study,with a mean age of(30.5 ±12.1)years,99 males and 79 females,126 with acute injuries and 52 with non-acute injuries;28 had avulsion fractures of the lateral malleolus or talar end confirmed by X-ray or surgery.Among the patients included in the study,181 had ATFL impairment(including 3 with bilateral ankle ATFL impairment),6 had no ATFL tear(normal or contusion),10 had partial tear,and 111 had complete tear in the acute period confirmed by surgery;2 had no ATFL tear,2 had partial tear,31 had complete tear,and 19 had ligament tear combined with scar hyperplasia in the non-acute period.2.Comparison of the diagnostic accuracy of different senior radiologists for ATFL tearsPartial tear,complete tear and tear combined with scar hyperplasia of ATFL were defined as ligament tear.There was no significant difference in the accuracy of SA,SB,JA and JB among 4 different senior radiologists in the diagnosis of ATFL tear,which were 96.7%,94.5%,95.6%and 94.5%,respectively.3.Comparison of different senior radiologists in the diagnosis of ATFL injury classificationConsidering normal ATFL,contusion,partial tear and tear combined with scar tissue hyperplasia as incomplete ATFL tears,the accuracy of diagnosing complete ATFL tears was lower in JA and JB(JA 67.4%,JB 63.0%)than in SA and SB(SA 77.9%,SB 76.8%,both P<0.05),and the diagnostic sensitivity(JA 69.0%,JB There was no statistically significant difference in diagnostic specificity between the four radiologists.For ATFL tears combined with scar tissue hyperplasia,only JA had a lower diagnostic accuracy than SA(51.9%vs 72.2%,P=0.029),while the diagnostic specificity(74.3%)was lower than SA and SB(SA 97.1%,SB 97.1%,both P=0.006).However,all four radiologists had lower diagnostic sensitivity,with SA having the highest,at 26.3%.4.Comparison of different senior sonographers in the diagnostic level of complete ATFL tears at different injury periodsFor complete ATFL tears in the acute period,the diagnostic accuracy of JA(75.6%,P=0.024)and JB(66.9%,P<0.001)was lower than that of SA and SB(SA 86.6%,SB 85.8%),and the diagnostic sensitivity(JA 76.6%,JB 67.6%)was also lower than that of SA and SB(SA 91.9%,SB 91.9%,all P<0.05%),and there was no difference in the diagnostic specificity among the four radiologists.However,for complete ATFL tears in the non-acute period,only JA had a lower diagnostic sensitivity(41.9%)than SA and SB(SA 55.6%,SB 55.6%)among junior doctors.There was no significant difference in diagnostic accuracy,sensitivity,and specificity between JB and SA and SB.5.Differential analysis of ultrasound signs of acute ATFL injury and ultrasound signs identified by radiologistsIn the acute period,complete ATFL tears showed ligament thickening and tension reduction,heterogeneous echo reduction(93.7%),a few showed increased echo(6.3%),and fibrous texture in the ligaments showed blurring.Compared with the reference signs of complete ATFL tears in the acute period,JA and JB were poor in identifying whether the ligaments were thickened and echogenic,JA was insufficient in judging whether the fibrous texture of the ligaments was clearly displayed,and JB was insufficient in judging whether the tension was reduced.At the same time,for partial tears of the ATFL,the ability of JA to assess ligament echogenicity and JB to assess thickness changes is also insufficient.6.Difference analysis of ultrasound signs of non-acute ATFL injury and ultrasound signs identified by radiologistsIn the non-acute period,96.8%of ATFL complete tears had ligament thickening,3.2%had no significant change in thickness,90.3%had hypotonia,9.7%had normal tension and 9.7%had heterogeneous echo reduction,and 96.8%had unclear ligament fiber texture.However,in non-acute ATFL injury,only ligaments with scar hyperplasia showed increased echogenicity.Compared with the reference signs,JB was significantly different from the reference signs in judging the ligament thickness,tension,echo changes of ATFL complete tears in the non-acute period and the ligament thickness of ATFL tears with scar hyperplasia.However,JA has insufficient ability to judge the fiber texture display of ligaments with complete ATFL tears.7.Comparison of different senior radiologists in the diagnosis of ATFL injury with avulsion fractureCompared with surgery or X-ray as the gold standard,there was no significant difference in the diagnostic sensitivity of the four radiologists for ATFL injury with avulsion fracture at different injury stages.The accuracy of JA in diagnosing acute ATFL injury with avulsion fracture was lower than that of SA(81.1%vs 91.3%,P=0.018),and the diagnostic accuracy of JA and JB was not significantly different from that of SB.The diagnostic specificity of JA and JB(JA 80.7%,JB 85.3%)was lower than that of SA(93.6%,P<0.050),and the diagnostic specificity of JA was also lower than that of SA(90.8%,P<0.050).However,for the non-acute period,the diagnostic accuracy and specificity of JA and JB were lower than those of SA(P<0.050),and there was no significant difference compared with SB.ConclusionThere was no difference in the accuracy of diagnosing whether ATFL tears were diagnosed by different senior radiologists,but due to the insufficient ability of junior radiologists to determine ATFL thickness and echo changes,it resulted in differences in their diagnostic level for complete ATFL tears in the acute period compared with senior radiologists.At the same time,the confusion of ultrasound signs and the special situation of scar tissue formation in non-acute ATFL injury affect the diagnostic level of radiologists for ATFL injury classification.Therefore,attention should be paid to the injury time of patients during the examination,and the degree of ATFL injury should be differentiated in combination with sonographic findings in order to better help radiologists improve the ability of ATFL injury classification and diagnosis.