Opposite Association Between Radiographic Lateral Ankle Instability and Osteochondral Lesions of the Talus in Patients with Ankle Inversion Injuries

Abstract

Category: Ankle Introduction/Purpose: Insufficient bony coverage surrounding the talus could cause considerable mechanical ankle instability, whereas excessive bony coverage could cause bone contusion at the time of injury and subsequent osteochondral lesions of the talus (OLT). This study aimed to investigate the relationship between radiographic lateral ankle instability and OLT in patients that sustained ankle inversion injuries. Methods: One-hundred-ninety-five patients (113 men and 83 women; mean age, 38.7 years; standard deviation, 8.8 years) with a history of ankle inversion injuries were included. All patients underwent ankle magnetic resonance imaging (MRI) and stress X-ray (varus stress and anterior drawer) examination. The tibiotalar tilt angle on varus stress X-ray, anterior translation of the talus on anterior-drawer lateral X-rays, bimalleolar tilt angle, and fibular position were radiographically determined. The anatomical grade of the lateral ankle ligament injury and the presence of OLTs were determined from MRI findings. Results: A greater lateral ankle ligament grade tends to increase the tibiotalar tilt angle (p=0.074), significantly affecting the anterior translation of the talus (p=0.036). The presence of radiographic lateral ankle instability (tibiotalar tilt angle =10°) showed opposite associations with the presence of OLT in the chi-square test (p=0.003). OLT was a negative significant factor (p=0.011) affecting the tibiotalar tilt angle in the multiple regression analysis (Table 1) and was negatively affected by the tibiotalar tilt angle (p=0.016) in the binary logistic regression analysis. Conclusion: This study showed an opposite association between lateral ankle instability and the development of OLT following ankle inversion injury. The role of bony predisposition in the development of sports injuries in the ankle should be considered and investigated further.