The risk factors attributing to the avulsion fracture of anterior inferior tibiofibular ligament (AITFL) in surgically treated ankle fractures.

Abstract

Objective: Avulsion fracture of the anterior inferior tibiofibular ligament (AITFL) combined with ankle fracture compromises the integrity of the ankle and affects its outcome. This study aimed to determine the incidence of AITFL fractures in surgically treated ankle fractures and to identify its related risk factors.

Methods: In this study, we enrolled a total of 156 patients with surgically treated ankle fractures. We extracted information from medical records on patients' demographic characteristics, body mass index, trauma mechanism, medical history, American Society of Anesthesiologists grade, and trauma mechanism. Ankle fractures were classified on X-ray images, and AITFL fractures according to the original or modified Wagstaffe classification based on radiographs and computed tomography (CT) images. The diagnostic capability of radiographs and risk factors for AITFL fractures were determined.

Results: Patients were divided into two groups: (1) with and (2) without AITFL avulsion fractures. Of the 156 cases, 77 (49.4%) anterior malleolar injuries were identified from CT images. Among these cases, 49 (63.6%) were solely Wagstaffe fractures, 18 (23.4%) were solely Chaput avulsion fractures, and 10 (13.0%) had both avulsion lesions. In 9 of the 10 cases with both avulsion fractures were supination-external rotation (SER) fractures. Moreover, there are 30 cases (39.0%) of AITFL avulsion fractures unidentifiable on the basis of plain radiographs. Age (OR 1.04, p < 0.001) and posterior Pilon fracture (OR 3.52, p = 0.002) were risk factors of AITFL avulsion fractures.

Conclusions: AITFL injuries appeared more commonly in ankle fractures than previously thought, and were frequently overlooked clinically. Recognizing AITFL fractures associated with ankle fractures through CT imaging is imperative, and timely repair is crucial for optimizing functional outcomes. Our findings provide clinicians with insights on such injuries for better surgical management.