Inverse Relationship Between Radiographic Lateral Ankle Instability and Osteochondral Lesions of the Talus in Patients With Ankle Inversion Injuries

Abstract

Background: Insufficient or excessive bony constraint surrounding the talus might contribute to the occurrence of ligamentous injury or bone contusion, respectively, at the time of ankle inversion injuries. This study aimed to investigate the relationship between radiographic lateral ankle instability and osteochondral lesions of the talus (OLT) following ankle inversion injuries. Methods: A total of 195 patients (113 men and 83 women; mean age, 38.7 years) with a history of ankle inversion injuries were included in this study. All patients underwent ankle magnetic resonance imaging (MRI) and stress radiography. The tibiotalar tilt angle on varus stress radiograph, anterior translation of the talus on anterior-drawer lateral radiographs, bimalleolar tilt angle, and fibular position were radiographically determined. The radiographic lateral ankle instability was defined as tibiotalar tilt angle ≥10 degrees, and the presence of OLT was confirmed on MR images. The relationship between the radiographic lateral ankle instability and the presence of OLT was statistically analyzed. Results: The presence of radiographic lateral ankle instability (tibiotalar tilt angle ≥10 degrees) showed an inverse relationship with that of OLT in the chi-squared test ( P = .003). An increased tibiotalar tilt angle was associated with lower incidence of OLT ( P = .011) in the multiple regression analysis, and the presence of OLT was associated with a decreased tibiotalar tilt angle ( P = .016) in the binary logistic regression analysis. Conclusions: This study showed an inverse relationship between lateral ankle instability and the development of OLT following ankle inversion injury. The role of bony constraint in the development of sports injuries in the ankle should be considered with these injuries. Level of Evidence: Level III, diagnostic, comparative study.