Kirschner Wire as a Reference Marker for the Positioning of a Syndesmotic Screw: A Radiological Study
Abstract Background: Without a reliable and static reference, the rate of eccentrically positioned distal syndesmotic screw trajectories is very high. Meanwhile, a malpositioned screw may result in poor outcomes and early osteoarthritis. As such, this article describes an additional method to improve surgeons’ ability to ideally place a screw trajectory. The purposes of our study were (1) to determine if an ideal space at 2.5 cm proximal to the plafond existed between the tibia and fibula for the placement of a Kirschner (K) wire and (2) to detect if it could act as a reliable and static fibular incisura plane reference.Methods: Computed tomography scans of 42 uninjured adult ankles with foot fractures were analysed to measure the tibiofibular vertical distance (TFVD) at 2.5 cm proximal to the tibial plafond on cross-sectional images. The TFVD was defined as the distance between two lines: Line 1 was tangent to the fibular incisura, and Line 2 was parallel to Line 1 along the medial border of the fibula. Patients were divided into 4 groups according to our TFVD data: 0–1, 1–2, 2–3, and 3–4 mm, and the number of patients in each group was counted.Results: The TFVD measured 2.23±1.01 mm (mean ± standard deviation) at 2.5 cm proximal to the plafond. According to our grouping, TFVD occurred at 25% of the distance from 2 to 3 mm in 47.6% of patients. Conclusions: Placing a 1.6-mm K-wire in the syndesmosis at 2.5 cm proximal to the tibial plafond is easy because of emerging TFVDs. The K-wire’s path is restricted to the anterior and posterior borders of the fibular incisura pass because of the limitation of the medial border of the fibula and syndesmosis tendon. Therefore, K-wire could be used as a reliable and static intraoperative reference of the fibular incisura plane through which surgeons can accurately place a screw trajectory.