A Prediction Model for Chronic Ankle Instability

Chronic ankle instability is a common problem that may follow an ankle sprain. Until a patient has developed chronic ankle instability they are ineligible for surgical treatment although early surgical treatment yields better results compared to surgical treatment of subjects that have experienced recurrent ankle sprains. However, treating all patients with an ankle sprain surgically is not an option due to the high amount of unnecessary invasive interventions. The objective of this study is to identify which patients will develop chronic ankle instability and to develop a model to predict which patients should receive early surgical treatment. In this prospective observational cohort all patients (older than 18 years) that report at the emergency department of the participating hospitals after a lateral ankle sprain, of whom an x-ray is made after positive Ottawa Ankle Rules and on which there is no visible fracture or other pathology. The main study parameter is a significant difference in patient characteristics, foot and ankle configuration and joint pathology between patients who develop chronic ankle instability and patients who do not experience recurrent ankle sprains and restriction during daily live after an initial sprain.