Ankle instability - overview of imaging methods

Abstract

Introduction: Ankle sprains are amongst the most common traumatic soft-tissue injuries and are especially prevalent at all levels of sport, with lateral sprains accounting for 85% of all such inju­ries. The lateral ankle ligament complex consists of the anterior talofibular ligament (ATFL), the cal­caneofibular ligament (CFL), and the posterior talofibular ligament (PTFL). Stretching and in more severe forms - tearing of the ligaments can eventually lead to a sense of instability in the ankle and predispose the patient to receive frequent ankle sprains, a condition known as ankle instability. To determine the integrity of the stabilizing structures of the ankle joint different imaging methods are considered. The following report aims to describe stress X-rays, ultrasound and MRI as methods as­sisting in the diagnostics of ankle instability. Materials and methods: For a period of 2.5 years (August, 2013 - December, 2015) 948 of the patients who presented with inversion ankle trauma in the orthopedic department of St. Anna Hospital, Var­na underwent testing for ankle injury. Out of the suspected for injury 92 underwent sonography of the ankle joint, 95 - stress X-ray and 26 - MRI. Results: The results of the currently presented methods show that they have different diagnostic val­ue. The choice of an imaging method should be based on secondary criteria such as - probability of detecting associated injuries, influence over the health status, time consumption and cost of the ex­amination. Conclusion: Diagnostics of ankle instability is no easy task for the clinician. Signs of damage to the ligaments, discovered after thorough physical examination require imaging methods to verify the in­jury. Based on the difference of stress X-rays, sonography and MRI in their complexity, cost and effi­ciency, they can be put in a diagnostic algorithm for approaching ankle instability.